Note: This page contains sample records for the topic overriding continental plate from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Analogue models of obliquely convergent continental plate boundaries  

Microsoft Academic Search

Analogue models are used to examine crustal-scale faulting at obliquely convergent continental plate boundaries. A uniform Coulomb material is deformed with basal kinematic boundary conditions to model two obliquely convergent lithospheric plates. The mantle part of one plate is assumed to detach from its overriding crust and then be subducted beneath the other plate. The obliquity of the collision is

David R. Burbidge; Jean Braun

1998-01-01

2

Three-dimensional dynamic models of subducting plate-overriding plate-upper mantle interaction  

NASA Astrophysics Data System (ADS)

We present fully dynamic generic three-dimensional laboratory models of progressive subduction with an overriding plate and a weak subduction zone interface. Overriding plate thickness (TOP) is varied systematically (in the range 0-2.5 cm scaling to 0-125 km) to investigate its effect on subduction kinematics and overriding plate deformation. The general pattern of subduction is the same for all models with slab draping on the 670 km discontinuity, comparable slab dip angles, trench retreat, trenchward subducting plate motion, and a concave trench curvature. The narrow slab models only show overriding plate extension. Subduction partitioning (vSP? / (vSP? + vT?)) increases with increasing TOP, where trenchward subducting plate motion (vSP?) increases at the expense of trench retreat (vT?). This results from an increase in trench suction force with increasing TOP, which retards trench retreat. An increase in TOP also corresponds to a decrease in overriding plate extension and curvature because a thicker overriding plate provides more resistance to deform. Overriding plate extension is maximum at a scaled distance of ~200-400 km from the trench, not at the trench, suggesting that basal shear tractions resulting from mantle flow below the overriding plate primarily drive extension rather than deviatoric tensional normal stresses at the subduction zone interface. The force that drives overriding plate extension is 5%-11% of the slab negative buoyancy force. The models show a positive correlation between vT? and overriding plate extension rate, in agreement with observations. The results suggest that slab rollback and associated toroidal mantle flow drive overriding plate extension and backarc basin formation.

Meyer, C.; Schellart, W. P.

2013-02-01

3

Role of the Overriding Plate in the Subduction Process: Insights from Numerical Models  

NASA Astrophysics Data System (ADS)

Active convergent margins are primarily shaped by the interplay among the subducting plate, overriding plate, and mantle. The effect of important forces, like far-field mantle flow, overriding plate motion, and inter-plate coupling, however, remains partially ambiguous. In a preliminary attempt to clarify their role, a self-consistent, visco-elastic, plane-strain, mechanical finite element model, in which subducting plate, overriding plate and mantle interact dynamically, is developed. In this quasi-static framework with a freely moving slab, trench, and inter-plate fault, the role of a compressive overriding plate on subduction zone kinematics, morphology and stress-state is characterized. A slab interacting solely with a semi-analytical three-dimensional mantle flow formulation shows that local non-induced mantle flow influences slab geometry and kinematics, adding an important dynamic term to the system. The impact of an overriding plate on this system is determined completely by overriding plate trench-ward motions and is only pertinent if the overriding plate actively advances the trench. A trench-ward moving overriding plate indents the slab and thereby enforces trench retreat and decreases slab dip. It also stimulates over-thrusting of the overriding plate onto the slab, and thereby permits mountain building within the overriding plate. Frictional resistance is observed to have a dominant local effect within the overriding plate as it is increasingly dragged down, thereby inhibiting the growth of overriding plate topography. A distinguishable effect on large-scale trench motions and deep slab dip is, however, absent for renormalized friction coefficients ranging up to about 0.2. Minor additional effects include a decrease in plate motions of about 15% and slab bending stresses of about 10%.

Funiciello, F.; Dinther, Y. V.; Morra, G.; Faccenna, C.

2009-12-01

4

Geometry of the Benioff zone and state of stress in the overriding plate in Central Mexico  

NASA Astrophysics Data System (ADS)

Analysis of depths and focal mechanisms of 16 small earthquakes in central Mexico, along with previous data, shows that (a) the subducted Cocos plate becomes subhorizontal between 110 and 275 km from the trench reaching a depth of about 50 km, and (b) the bottom part of the overriding continental plate is in tensional stress regime. Neotectonic structures in central Mexico and stress orientations (estimated from borehole elongations, cinder cone alignments, and fault-slip analysis) in the Trans Mexican Volcanic Belt, which lies in the northeastern portion of the area under study, also indicate the same stress regime. Absolute motion of the North American plate in the region has a component normal to the trench of 20 mm/yr which, if true, would result in compressional stress in the upper plate if the trench position is fixed in an absolute frame of reference. If we allow for seaward retreat of the trench, then the tensional stress in the overriding plate and the observed geometry of the Benioff zone can be explained. This, however, implies that seaward retreat of a trench is possible even for a young (about 15 m.y. old) subducting slab. Alternatively, tectonic erosion of the leading edge of the continent could give rise to the tensional stress but would not explain the geometry of the Benioff zone.

Singh, Shri K.; Pardo, Mario

1993-07-01

5

Plate movement and continental magmatism  

Microsoft Academic Search

Extensive magmatic and metamorphic events have occurred within the Earth's continental crust far from plate margins. During the last 800 million years Africa has only been host to such events during the breaks in the systematic motion of the African plate. This suggests that sublithospheric heat sources have little effect on a moving plate and can only produce recognisable effects

J. C. Briden

1974-01-01

6

Stress fields of the overriding plate at convergent margins and beneath active volcanic arcs.  

PubMed

Tectonic stress fields in the overriding plate at convergent plate margins are complex and vary on local to regional scales. Volcanic arcs are a common element of overriding plates. Stress fields in the volcanic arc region are related to deformation generated by subduction and to magma generation and ascent processes. Analysis of moment tensors of shallow and intermediate depth earthquakes in volcanic arcs indicates that the seismic strain field in the arc region of many convergent margins is subhorizontal extension oriented nearly perpendicular to the arc. A process capable of generating such a globally consistent strain field is induced asthenospheric corner flow below the arc region. PMID:17774792

Apperson, K D

1991-11-01

7

Subduction of the Caribbean Plate and Basement Uplifts in the Overriding South American Plate  

NASA Astrophysics Data System (ADS)

The new tectonic interpretations presented in this paper are based on geologic field mapping and gravity data supplemented by well logs, seismic profiles, and radiometric and earthquake data. The present Caribbean-South American plate boundary is the South Caribbean marginal fault, where subduction is indicated by folding and thrusting in the deformed belt and a seismic zone that dips 30° to the southeast and terminates 200 km below the Maracaibo Basin. The Caribbean-South American convergence rate is estimated as 1.9 ± 0.3 cm/yr on the basis of the 390-km length of the seismic zone and a thermal equilibration time of 10 m.y. The Caribbean-South American convergence has produced a northwest-southeast maximum principal stress direction ?1 in the overriding South American plate. The mean ?1 direction for the Maracaibo-Santa Marta block is 310° ± 10° based on earthquake focal mechanism determinations, and structural and gravity data. On the overriding South American plate, basement blocks have been uplifted 7-12 km in the last 10 m.y. to form the Venezuelan Andes, Sierra de Perija, and the Colombian Santa Marta massif. Crystalline basement of the Venezuelan Andes has been thrust to the northwest over Tertiary sediments on a fault dipping about 25° and extending to the mantle. In the Sierra de Perija, Mesozoic sediments have been thrust 16-26 km to the northwest over Tertiary sandstones along the Cerrejon fault. A thrust fault dipping 15° ± 10° to the southeast is consistent with field mapping, and gravity and density data. The Santa Marta massif has been uplifted 12 km in the last 10 m.y. by northwest thrusting over sediments. The basement block overthrusts of the Perijas, Venezuelan Andes, and the Santa Marta massif are Pliocene-Pleistocene analogs for Laramide orogenic structures in the middle and southern Rocky Mountains of the United States. The nonmagmatic basement block uplifts along low-angle thrust faults reveal horizontal compression in the overriding plate over 500 km from the convergent margin. Present-day east northeast-west southwest (080°) compression is indicated by earthquake focal mechanisms and strike slip motion on the Bocono fault. These earthquakes are intraplate deformation associated with east-west (080°) Nazca-South American convergence.

Kellogg, J. N.; Bonini, W. E.

1982-06-01

8

The role of non-uniform overriding plates on slab dip variability along the trench. Insights from 3D numerical modeling  

NASA Astrophysics Data System (ADS)

Although subduction is the primary force driving plate tectonics, some factors controlling the dynamics and the geometry of subduction processes are still poorly understood. Specifically, the effect of the thermal state of the subducting and overriding plates on the slab dip has been systematically studied in previous works by means of 2D numerical modeling. These 2D models showed that slabs subducting under an old overriding plate are affected by an increased hydrodynamic suction, due to the lower temperature and therefore higher viscosity, of the mantle wedge, which leads to a lower subduction angle, and eventually to the formation of flat slab segments. Two limitations of these previous models are: 1) the 2D approach only accounts for the poloidal component of flow, and 2) subduction is achieved by imposing a kinematic boundary condition (imposed convergence velocity for the subducting plate). Here we present the results of 3D non-Newtonian thermo-mechanical numerical models, considering either kinematically-driven or self-sustained subduction, to test the influence of thermal state of both the overriding and subducting plates on subduction dynamics and slab geometry. The age of both the overriding and subducting plates is systematically varied in order to test its effect on the slab dip at different depth ranges. We have also tested the effect of overriding plates with a non-uniform thermal state in the trench parallel direction to study variations of the slab dip along strike. Modeling results are qualitatively compared to the large dip variability of the Cocos slab and the flat-slab segment of the Pacific plate subducting beneath Northern Chile. We hypothesize that a significant part of this variability is likely related to the change of the thermal state of the overriding plates due to variations in age of the continental crustal blocks. The 3D approach followed in this study accounts for both the poloidal and toroidal components of flow, thus allowing us to compare the results with observations of seismic anisotropy in these regions.

Rodriguez-Gonzalez, J.; Billen, M. I.; Negredo, A. M.

2011-12-01

9

The Continental Plates are Getting Thicker.  

ERIC Educational Resources Information Center

Reviews seismological studies that provide evidence of the existence of continental roots beneath the continents. Suggests, that through the collisions of plate tectonics, continents stabilized part of the mobile mantle rock beneath them to form deep roots. (ML)

Kerr, Richard A.

1986-01-01

10

Modelling continental deformation within global plate tectonic reconstructions  

Microsoft Academic Search

A limitation of regional and global plate tectonic models is the way continental deformation is represented. Continental blocks are typically represented as rigid polygons - overlaps or gaps between adjacent continental blocks represent extension or compression respectively. Full-fit reconstructions of major ocean basins result in large overlaps between the conjugate continental plates, on the basis that the continental margins are

S. Williams; J. Whittaker; C. Heine; P. Müller

2010-01-01

11

The potential influence of subduction zone polarity on overriding plate deformation, trench migration and slab dip angle  

NASA Astrophysics Data System (ADS)

A geodynamic model exists, the westward lithospheric drift model, in which the variety of overriding plate deformation, trench migration and slab dip angles is explained by the polarity of subduction zones. The model predicts overriding plate extension, a fixed trench and a steep slab dip for westward-dipping subduction zones (e.g. Mariana) and predicts overriding plate shortening, oceanward trench retreat and a gentle slab dip for east to northeastward-dipping subduction zones (e.g. Chile). This paper investigates these predictions quantitatively with a global subduction zone analysis. The results show overriding plate extension for all dip directions (azimuth ? = - 180° to 180°) and overriding plate shortening for dip directions with ? = - 90° to 110°. The wide scatter in data negate any obvious trend and only local mean values in overriding plate deformation rate indicate that overriding plate extension is somewhat more prevalent for west-dipping slabs. West-dipping subduction zones are never fixed, irrespective of the choice of reference frame, while east to northeast-dipping subduction zones are both retreating and advancing in five out of seven global reference frames. In addition, westward-dipping subduction zones have a range in trench-migration velocities that is twice the magnitude of that for east to northeastward-dipping slabs. Finally, there is no recognizable correlation between slab dip direction and slab dip angle. East to northeast-dipping slabs (? = 30° to 120°) have shallow (0 125 km) slab dip angles in the range 10 60° and deep (125 670 km) slab dip angles in the range 40 82°, while west-dipping slabs (? = - 60° to - 120°) have shallow slab dip angles in the range 19 50° and deep slab dip angles in the range 25 86°. Local mean deep slab dip angles are nearly identical for east and west-dipping slabs, while local mean shallow slab dip angles are lower by only 4.7 8.1° for east to northeast-dipping slabs. It is thus concluded that overall, there is no observational basis to support the three predictions made by the westward drift model, and for some sub-predictions the observational basis is very weak at most. Alternative models, which incorporate and underline the importance of slab buoyancy-driven trench migration, slab width and overriding plate motion, are better candidates to explain the complexity of subduction zones, including the variety in trench-migration velocities, overriding plate deformation and slab dip angles.

Schellart, W. P.

2007-12-01

12

Plate Tectonic Models for Orogeny at Continental Margins  

Microsoft Academic Search

IN the theory of plate tectonics convergent plate junctures are the loci of orogeny1, marked surficially by arc-trench systems2, and the margin of one plate is consumed in a trench subduction zone. The overriding or consuming plate margin is characterized by a magmatic belt supporting both arc volcanism and batholithic intrusion at crustal levels. For rock assemblages formed within active

William R. Dickinson

1971-01-01

13

Paleomagnetism, continental drift, and plate tectonics  

Microsoft Academic Search

The title of this chapter might induce the reader to expect rather more than what actually is being offered; this review restricts itself to those aspects of paleomagnetism that are related to continental drift, polar wandering, and plate tectonics, and vice versa. A sensu lato interpretation would not only lead to a lengthy recitation; it would also in fact be

Rob Van der Voo

1975-01-01

14

Trench-parallel flow in the southern Ryukyu subduction system: Effects of progressive rifting of the overriding plate  

NASA Astrophysics Data System (ADS)

AbstractThe Okinawa trough in the Ryukyu subduction system is one of a few actively extending back arc basins within the <span class="hlt">continental</span> lithosphere. Recent shear-wave splitting measurements show variable fast directions along the trough suggesting a complex three-dimensional mantle flow field. In this study we use numerical subduction models to demonstrate that the thickness variations of the <span class="hlt">continental</span> lithosphere bounding the edge of a subduction zone can result in complicated mantle circulation and regional dynamics. The model results for the southern Ryukyu show a combination of two effects: Along the Okinawa trough, the increasing thickness of the <span class="hlt">overriding</span> Eurasian <span class="hlt">plate</span> toward Taiwan due to a gradually diminishing rifting induces pressure gradients that drive trench-parallel flow to the edge in the shallow portion of the mantle wedge, and the thick Eurasian lithosphere to the west effectively blocks and diverts this along-arc flow and limits the toroidal flow around the slab edge below it. The toroidal flow thus enters the mantle wedge at depths of more than about 100 km, opposite in direction with and largely below the along-arc flow. These combined geometry effects of the Eurasian lithosphere create an intricate three-dimensional flow structure at the southern edge of the Ryukyu subduction zone. Model predictions for lattice preferred orientations of olivine aggregates show rotation patterns that agree with the observed shear-wave splitting patterns. This three-dimensional scenario echoes the geochemical and seismological evidence worldwide that indicates complex, depth-varying mantle circulations in subduction systems.</p> <div class="credits"> <p class="dwt_author">Lin, Shu-Chuan; Kuo, Ban-Yuan</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">15</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013GeoJI.195...47D"> <span id="translatedtitle">Three-dimensional dynamic laboratory models of subduction with an <span class="hlt">overriding</span> <span class="hlt">plate</span> and variable interplate rheology</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Subduction zones are complex 3-D features in which one tectonic <span class="hlt">plate</span> sinks underneath another into the deep mantle. During subduction the <span class="hlt">overriding</span> <span class="hlt">plate</span> (OP) remains in physical contact with the subducting <span class="hlt">plate</span> and stresses generated at the subduction zone interface and by mantle flow force the OP to deform. We present results of 3-D dynamic laboratory models of subduction that include an OP. We introduce new interplate materials comprising homogeneous mixtures of petrolatum and paraffin oil to achieve progressive subduction. The rheology of these mixtures is characterized by measurements using a strain rate controlled rheometer. The results show that the strength of the mixture increases with petrolatum content, which can be used as a proxy for the degree of mechanical coupling along the subduction interface. Results of subduction experiments are presented with different degrees of mechanical coupling and the influence this has on the dynamics and kinematics of subduction. The modelling results show that variations in the degree of mechanical coupling between the <span class="hlt">plates</span> have a major impact on subduction velocities, slab geometry and the rate of OP deformation. In all experiments the OP is displaced following trench migration and experiences overall extension localized in the <span class="hlt">plate</span> interior. This suggests that OP deformation is driven primarily by the toroidal component of subduction-related mantle return flow. The subduction rate is always very slow in experiments with medium mechanical coupling, and subduction stops prematurely in experiments with very high coupling. This implies that the shear forces along the <span class="hlt">plate</span> interface in natural subduction zone systems must be relatively low and do not vary significantly. Otherwise a higher variability in natural subduction velocities should be observed for mature, non-perturbed subduction zones. The required low shear force is likely controlled by the rheology of highly hydrated sedimentary and basaltic rocks.</p> <div class="credits"> <p class="dwt_author">Duarte, João C.; Schellart, Wouter P.; Cruden, Alexander R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">16</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2001JGR...106..703Z"> <span id="translatedtitle">Role of ocean-continent contrast and <span class="hlt">continental</span> keels on <span class="hlt">plate</span> motion, net rotation of lithosphere, and the geoid</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Three-dimensional spherical shell models of mantle convection have been formulated to investigate the effects of ocean-continent contrast (i.e., different viscosity for <span class="hlt">continental</span> and oceanic lithospheres) and <span class="hlt">continental</span> keels on <span class="hlt">plate</span> motion, net rotation of lithosphere (i.e., degree 1 toroidal <span class="hlt">plate</span> motion), and the geoid. The models include relatively realistic <span class="hlt">plate</span> rheology (i.e., strong <span class="hlt">plate</span> interiors and weak <span class="hlt">plate</span> margins) and <span class="hlt">continental</span> keel structure based on seismic models. The mantle flow in the models is driven by slab buoyancy. The models demonstrate that the ocean-continent contrast and <span class="hlt">continental</span> keels have minor effects on the long-wavelength geoid (for degrees 2-5). However, <span class="hlt">continental</span> keels <span class="hlt">overriding</span> subducted slabs, for example in North America, can produce large negative gravity anomalies at a regional scale. This may have important implications to interpreting the gravity anomalies in North America. Our models show that when <span class="hlt">plates</span> bounded by weak <span class="hlt">plate</span> margins have the same thickness, neither weak <span class="hlt">plate</span> margins nor the ocean-continent contrast efficiently excite net rotation of lithosphere, although they excite toroidal motion at higher harmonic degrees. However, <span class="hlt">plate</span> thickness variations like <span class="hlt">continental</span> keels excite the net rotation. In spite of their ability to excite the net rotation, <span class="hlt">continental</span> keels as thick as 300 km cannot provide the necessary coupling to the deep mantle to produce the observed net rotation of lithosphere and slow <span class="hlt">continental</span> motion if there is a weak asthenosphere underlying them. If the thermomechanic structure of North American <span class="hlt">continental</span> upper mantle derived from seismic and heat flow studies is representative, our models suggest that the temperature- and pressure-dependent mantle rheology may not produce sufficiently high viscosity below <span class="hlt">continental</span> keels that is needed to explain the observed <span class="hlt">plate</span> motion. Our study hints the necessity to include more realistic treatment of <span class="hlt">plate</span> boundaries in future studies to assess possible effects of <span class="hlt">plate-plate</span> coupling on <span class="hlt">plate</span> motion.</p> <div class="credits"> <p class="dwt_author">Zhong, Shijie</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">17</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013SolED...5..427S"> <span id="translatedtitle">New constraints on the geometry of the subducting African <span class="hlt">plate</span> and the <span class="hlt">overriding</span> Aegean <span class="hlt">plate</span> obtained from P receiver functions and seismicity</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">New combined P receiver functions and seismicity data obtained from the EGELADOS network employing 65 stations within the Aegean constrained new information on the geometry of the Hellenic subduction zone. The dense network and large dataset enabled us to accurately estimate the Moho of the <span class="hlt">continental</span> Aegean <span class="hlt">plate</span> across the whole area. Presence of a negative contrast at the Moho boundary indicating the serpentinized mantle wedge above the subducting African <span class="hlt">plate</span> was clearly seen along the entire forearc. Furthermore, low seismicity was observed within the serpentinized mantle wedge. We found a relatively thick <span class="hlt">continental</span> crust (30-43 km) with a maximum thickness of about 48 km beneath the Peloponnesus Peninsula, whereas a thinner crust of about 27-30 km was observed beneath western Turkey. The crust of the <span class="hlt">overriding</span> <span class="hlt">plate</span> is thinning beneath the southern and central Aegean (Moho depth 23-27 km). Moreover, P receiver functions significantly imaged the subducted African Moho as a strong converted phase down to a depth of 180 km. However, the converted Moho phase appears to be weak for the deeper parts of the African <span class="hlt">plate</span> suggesting reduced dehydration and nearly complete phase transitions of crustal material into denser phases. We show the subducting African crust along 8 profiles covering the whole southern and central Aegean. Seismicity of the western Hellenic subduction zone was taken from the relocated EHB-ISC catalogue, whereas for the eastern Hellenic subduction zone, we used the catalogues of manually picked hypocenter locations of temporary networks within the Aegean. P receiver function profiles significantly revealed in good agreement with the seismicity a low dip angle slab segment down to 200 km depth in the west. Even though, the African slab seems to be steeper in the eastern Aegean and can be followed down to 300 km depth implying lower temperatures and delayed dehydration towards larger depths in the eastern slab segment. Our results showed that the transition between the western and eastern slab segments is located beneath the southeastern Aegean crossing eastern Crete and the Karpathos basin. High resolution P receiver functions also clearly resolved the top of a strong low velocity zone (LVZ) at about 60 km depth. This LVZ is interpreted as asthenosphere below the Aegean <span class="hlt">continental</span> lithosphere and above the subducting slab. Thus the Aegean mantle lithosphere seems to be 30-40 km thick, which means that its thickness increased again since the removal of the mantle lithosphere about 15 to 35 Ma ago.</p> <div class="credits"> <p class="dwt_author">Sodoudi, F.; Bruestle, A.; Meier, T.; Kind, R.; Friederich, W.; Egelados Working Group</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">18</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1998JGR...10315221B"> <span id="translatedtitle">Analogue models of obliquely convergent <span class="hlt">continental</span> <span class="hlt">plate</span> boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Analogue models are used to examine crustal-scale faulting at obliquely convergent <span class="hlt">continental</span> <span class="hlt">plate</span> boundaries. A uniform Coulomb material is deformed with basal kinematic boundary conditions to model two obliquely convergent lithospheric <span class="hlt">plates</span>. The mantle part of one <span class="hlt">plate</span> is assumed to detach from its <span class="hlt">overriding</span> crust and then be subducted beneath the other <span class="hlt">plate</span>. The obliquity of the collision is assumed to remain constant throughout the deformation. Experiments are run with obliquities ranging from pure convergence (low obliquity) to pure strike slip (high obliquity). Reverse faults are observed for all obliquities with a nonzero convergent component. By contrast, only collisions with a large amount of strike slip motion exhibit wrench faulting. In experiments dominated by their convergent component, the strike slip motion is totally accommodated by oblique slip along the reverse faults. Strain partitioning between reverse faults and wrench faults is only observed for experiments run above a certain critical partitioning obliquity. Prom the observed initial faults, we can deduce the change in orientation in the principal stress triad as the obliquity is changed. We propose that the initial direction of maximum compressive stress (?1) rotates horizontally as the obliquity is changed, which in turn affects the geometry of the initial faults formed in the material. In the case of reverse faults, the rotation increases their dip measured along the direction of pure convergence. The relative magnitude of the minimum horizontal stress and the vertical stress determine whether reverse faults or strike slip faults are the first to form. Although long term deformation is more difficult to analyze, a simple relationship for the angle at which strain partitioning occurs is derived.</p> <div class="credits"> <p class="dwt_author">Burbidge, David R.; Braun, Jean</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-07-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">19</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14848609"> <span id="translatedtitle"><span class="hlt">Continental</span> tectonics in the aftermath of <span class="hlt">plate</span> tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">It is shown that the basic tenet of <span class="hlt">plate</span> tectonics, rigid-body movements of large <span class="hlt">plates</span> of lithosphere, fails to apply to <span class="hlt">continental</span> interiors. There, buoyant <span class="hlt">continental</span> crust can detach from the underlying mantle to form mountain ranges and broad zones of diffuse tectonic activity. The role of crustal blocks and of the detachment of crustal fragments in this process is</p> <div class="credits"> <p class="dwt_author">Peter Molnar</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">20</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51846399"> <span id="translatedtitle">The Influence of <span class="hlt">Continental</span> Roots on <span class="hlt">Plate</span> Motions and <span class="hlt">Plate</span>-Mantle Coupling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Mechanical coupling between the convecting mantle and Earth's lithospheric <span class="hlt">plates</span> determines how buoyancy forces within the deep mantle are expressed at the surface as <span class="hlt">plate</span> motions and lithospheric stresses. Strong viscosity variations associated with deeply-penetrating <span class="hlt">continental</span> roots have been shown to significantly modify this <span class="hlt">plate</span>-mantle coupling. In this study, we investigate the impact of <span class="hlt">continental</span> roots on regional variations in</p> <div class="credits"> <p class="dwt_author">J. van Summeren; C. P. Conrad; C. R. Lithgow-Bertelloni</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_1");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a style="font-weight: bold;">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_2");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_1 div --> <div id="page_2" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_1");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a style="font-weight: bold;">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_3");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">21</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/jb/v087/iB13/JB087iB13p10677/JB087iB13p10677.pdf"> <span id="translatedtitle"><span class="hlt">Continental</span> Rifting and the Implications For <span class="hlt">Plate</span> Tectonic Reconstructions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Previous <span class="hlt">plate</span> tectonic reconstructions have tried to recreate the pre-rifiing (Pangea) configuration of the continents by matching contours or lineaments that are thought to represent the <span class="hlt">continental</span> boundaries. Such reconstructions have the inherent assumptions that no extension occurs within the continent during rifting, that the <span class="hlt">continental</span> boundaries are isochrons, and that the continents rift without distortion. This paper proposes a</p> <div class="credits"> <p class="dwt_author">Gregory E. Vink</p> <p class="dwt_publisher"></p> <p class="publishDate">1982-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">22</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52871962"> <span id="translatedtitle"><span class="hlt">Continental</span> volcanism, xenoliths, and lithospheric <span class="hlt">plate</span> tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A comparison of data on the evolution of Cenozoic volcanism in the Baikal rift zone and Mongolia and of Pliocene-Quaternary volcanism in the Minor Caucasus indicates that the data do not support the theory of <span class="hlt">plate</span> tectonics. It is shown that the evolution of these regions as well as the evolution of the deep-magma composition and that of the deep</p> <div class="credits"> <p class="dwt_author">Iu. S. Genshaft; A. Ia. Saltykovskii</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">23</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/47387730"> <span id="translatedtitle">Developing the <span class="hlt">plate</span> tectonics from oceanic subduction to <span class="hlt">continental</span> collision</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The studies of <span class="hlt">continental</span> deep subduction and ultrahigh-pressure metamorphism have not only promoted the development of solid\\u000a earth science in China, but also provided an excellent opportunity to advance the <span class="hlt">plate</span> tectonics theory. In view of the nature\\u000a of subducted crust, two types of subduction and collision have been respectively recognized in nature. On one hand, the crustal\\u000a subduction occurs</p> <div class="credits"> <p class="dwt_author">YongFei Zheng; Kai Ye; LiFei Zhang</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">24</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=N19990099116"> <span id="translatedtitle">Viscoelastic Postseismic Rebound to Strike-Slip Earthquakes in Regions of Oblique <span class="hlt">Plate</span> Convergence.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">According to the slip partitioning concept, the trench parallel component of relative <span class="hlt">plate</span> motion in regions of oblique convergence is accommodated by strike-slip faulting in the <span class="hlt">overriding</span> <span class="hlt">continental</span> lithosphere. The pattern of postseismic surface defo...</p> <div class="credits"> <p class="dwt_author">S. C. Cohen</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">25</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUFM.T42A..04D"> <span id="translatedtitle">From Oceanic Lithosphere Subduction To <span class="hlt">Continental</span> Collision: Influence Of The <span class="hlt">Plate</span> Contact</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We showed recently that the overall dynamics of oceanic subduction differ depending on whether the <span class="hlt">plate</span> contact is a fault or a channel (De Franco & al., 2007. GJI, doi: 10.1111/j.1365-246X.2006.03498.x). Here we investigate how the <span class="hlt">plate</span> contact affects the transition from oceanic lithosphere subduction to <span class="hlt">continental</span> collision. We use a finite element method to solve the heat and the time dependent momentum equations for elastic, (power law) viscous and plastic rheologies. For the same rheological properties and driving forces , varying the nature of the <span class="hlt">plate</span> contact leads to three types of responses: subduction of the entire <span class="hlt">continental</span> lithosphere, shear delamination of the <span class="hlt">continental</span> crust or slab break-off. We make the following observations from our numerical experiments. The presence of a subduction channel promotes coherent and, when the boundary conditions allow it, <span class="hlt">plate</span>-like subduction of the <span class="hlt">continental</span> margin. In models with a subduction fault, coherent subduction of the incoming <span class="hlt">continental</span> lithosphere occurs when the colliding passive margin has a gentle ocean-continent transition. The approaching <span class="hlt">continental</span> sliver starts to subduct and the subduction is characterized by a non-<span class="hlt">plate</span>-like behavior, slower subduction velocity than in channel models and strong slab deformation. If the <span class="hlt">continental</span> margin is steep and the strength of the incoming <span class="hlt">continental</span> crust is high, fault models result in locking of the trench, eventually leading to slab break-off. If the crustal strength is relatively low, shear delamination of the upper crust is expected. In the channel model this type of delamination never occurs. The tectonic setting does not significantly affect the nature of the model response. We conclude that the <span class="hlt">plate</span> contact type, together with the geometrical and rheological properties of the incoming <span class="hlt">continental</span> fragment, is a crucial subduction characteristic controlling the response of <span class="hlt">continental</span> collision during the transition from oceanic subduction to <span class="hlt">continental</span> collision. During the early stage of <span class="hlt">continental</span> collision, the <span class="hlt">plate</span> contact plays a more relevant role than the magnitude of slab pull and the tectonic setting.</p> <div class="credits"> <p class="dwt_author">de Franco, R.; Govers, R.; Wortel, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">26</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFM.T42A..04D"> <span id="translatedtitle">From Oceanic Lithosphere Subduction To <span class="hlt">Continental</span> Collision: Influence Of The <span class="hlt">Plate</span> Contact</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We showed recently that the overall dynamics of oceanic subduction differ depending on whether the <span class="hlt">plate</span> contact is a fault or a channel (De Franco & al., 2007. GJI, doi: 10.1111/j.1365-246X.2006.03498.x). Here we investigate how the <span class="hlt">plate</span> contact affects the transition from oceanic lithosphere subduction to <span class="hlt">continental</span> collision. We use a finite element method to solve the heat and the time dependent momentum equations for elastic, (power law) viscous and plastic rheologies. For the same rheological properties and driving forces , varying the nature of the <span class="hlt">plate</span> contact leads to three types of responses: subduction of the entire <span class="hlt">continental</span> lithosphere, shear delamination of the <span class="hlt">continental</span> crust or slab break-off. We make the following observations from our numerical experiments. The presence of a subduction channel promotes coherent and, when the boundary conditions allow it, <span class="hlt">plate</span>-like subduction of the <span class="hlt">continental</span> margin. In models with a subduction fault, coherent subduction of the incoming <span class="hlt">continental</span> lithosphere occurs when the colliding passive margin has a gentle ocean-continent transition. The approaching <span class="hlt">continental</span> sliver starts to subduct and the subduction is characterized by a non-<span class="hlt">plate</span>-like behavior, slower subduction velocity than in channel models and strong slab deformation. If the <span class="hlt">continental</span> margin is steep and the strength of the incoming <span class="hlt">continental</span> crust is high, fault models result in locking of the trench, eventually leading to slab break-off. If the crustal strength is relatively low, shear delamination of the upper crust is expected. In the channel model this type of delamination never occurs. The tectonic setting does not significantly affect the nature of the model response. We conclude that the <span class="hlt">plate</span> contact type, together with the geometrical and rheological properties of the incoming <span class="hlt">continental</span> fragment, is a crucial subduction characteristic controlling the response of <span class="hlt">continental</span> collision during the transition from oceanic subduction to <span class="hlt">continental</span> collision. During the early stage of <span class="hlt">continental</span> collision, the <span class="hlt">plate</span> contact plays a more relevant role than the magnitude of slab pull and the tectonic setting.</p> <div class="credits"> <p class="dwt_author">de Franco, R.; Govers, R.; Wortel, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">27</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42769369"> <span id="translatedtitle">Yin and yang of <span class="hlt">continental</span> crust creation and destruction by <span class="hlt">plate</span> tectonic processes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Earth's <span class="hlt">continental</span> crust today is both created and destroyed by <span class="hlt">plate</span> tectonic processes, a balance that is encapsulated by the traditional Chinese concept of yin–yang, whereby dualities act in concert as well as in opposition. Yin–yang conceptualizations of crustal growth and destruction are mostly related to <span class="hlt">plate</span> tectonics; both occur mostly at subduction zones, by arc magmatic creation and by</p> <div class="credits"> <p class="dwt_author">Robert J. Stern; David W. Scholl</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">28</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T13H..06M"> <span id="translatedtitle"><span class="hlt">Overriding</span> <span class="hlt">plate</span> structure of the Nicaragua convergent margin: Constraints on the limits of the seismogenic zone and the 1992 tsunami earthquake</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We present two 2D seismic velocity models of the Nicaragua convergent erosional margin along perpendicular WAS profiles acquired in the rupture area of the 1992 tsunami earthquake. The models focus on the structure of the upper <span class="hlt">plate</span> and the geometry of the <span class="hlt">plate</span> boundary interface. In the trench-perpendicular profile (NIC20), the basement shows increasing velocity from top to bottom and from the trench towards the coast. In the absence of an accretionary wedge, the velocity gradient reflects a progressive decrease in the degree of rock fracturing of the Mesozoic igneous basement, from almost complete disaggregation at < 4 km from the trench to aseismic ridge-like crustal rocks at ~75 km, where the upper <span class="hlt">plate</span> is ~20±0.5 km-thick. Upper mantle-like velocities are obtained at a depth of ~10 km beneath the ~5 km-thick Sandino basin, which means that the mantle wedge is shallow and extends up to ~90 km from the trench. The trench-parallel profile (NIC125) is similar in terms of velocity structure and depth of the inter-<span class="hlt">plate</span> boundary (18±0.5 km). It displays a laterally-uniform structure, indicating that the NIC20 model is representative of the upper <span class="hlt">plate</span> structure along the whole rupture area of the 1992 earthquake. A mismatch between the WAS inter-<span class="hlt">plate</span> reflector and that imaged along coincident MCS profiles can be explained by a velocity anisotropy of 17±2%, probably related with locally-enhanced rock fracturing and fluid percolation. The updip limit of the seismogenic zone is difficult to define based on regional seismicity and aftershock distribution because the aftershocks nucleate up to the trench. The frontal part of the <span class="hlt">overriding</span> <span class="hlt">plate</span> is probably too fractured to store elastic energy, unless the presence of local asperities makes it conditionally stable. The downdip limit (~25 km depth), defined by an abrupt decrease in the number of aftershocks and by a gap in the regional seismicity, occurs near the tip of the mantle wedge, indicating that it is probably controlled by the presence of a serpentinized mantle wedge right beneath the Sandino basin. The hypocenter of the 1992 main shock is not particularly shallow (~21 km), but seismological data indicate that it triggered sub-events in the conditionally stable area. One of these sub-events occurred near the SE limit of the rupture zone, which is the area of maximum inferred co-seismic slip and seafloor displacement and the place where MCS data have revealed the presence of a subducted seamount. Given that sediments are absent on top of the subducting seamount, we hypothesize that the seismic rupture is controlled by the nature of the basement rocks. In this case the average rupture velocity of this sub-event would be 1.4-1.7 km/s, and the rigidity 9-14 GPa, consistent with estimations based on seismological data analysis. Thus, the slow propagation and long duration of the 1992 tsunami earthquake could be explained by rupture propagating within the fractured, conditionally stable part the crystalline basement and not into the sediments.</p> <div class="credits"> <p class="dwt_author">Melendez, A.; Sallares, V.; Prada, M.; Ranero, C. R.; McIntosh, K. D.; Grevemeyer, I.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">29</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=COM7310185"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics, Sea-Floor Spreading, and <span class="hlt">Continental</span> Drift.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Over the past decade a geologic revolution has transpired. It can be summarized in the expression, 'the new global tectonics,' or more succinctly as <span class="hlt">plate</span> tectonics. This, in turn, involves sea-floor spreading, descending lithospheric slabs, transform fau...</p> <div class="credits"> <p class="dwt_author">R. S. Dietz</p> <p class="dwt_publisher"></p> <p class="publishDate">1972-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">30</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011PhDT.......191B"> <span id="translatedtitle">Fault zone structure and evolution at <span class="hlt">continental</span> <span class="hlt">plate</span> boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Decades of research has illustrated that the <span class="hlt">continental</span> lithosphere, particularly the crust within it, is compositionally evolved and heterogeneous. The compositional heterogeneity is clearly associated with rheological layering, yet the precise rheological behavior of each layer has proven difficult to quantify. In particular, two important questions have remained unresolved for several decades. (1) What is the integrated and peak strength of the <span class="hlt">continental</span> lithosphere and where does the peak strength reside? (2) To what degree is deformation localized into faults and shear zones at different depths? A variety of sub-disciplines in the earth sciences, including geology, geodesy, and geophysics have focused on these issues for both modern and ancient <span class="hlt">continental</span> orogens. In this thesis, I address these two questions, both directly and indirectly, but from two quite separate sub-disciplines: active tectonics and structural geology. Chapter 2 focuses on whether discrepancies in geologic vs. geodetic slip rates are real, given the uncertainties in geologic slip rate estimates. In Chapters 3 and 4 the magnitude of stress within the middle and lower crust is quantified for two separate tectonic settings: the Whipple Mountains in eastern California (Chapter 3), representing post-collisional extension, and the Sierra Alhamilla in southern Spain (Chapter 4), representing syn-collisional extension. The stress profiles differ in detail, but lead to the same overarching conclusions: (1) the magnitude of stress at the brittle-ductile transition is high, consistent with the extrapolation of Byerlee's law at hydrostatic pore fluid pressures; and (2) the decreases in stress with depth and the associated strain rates are consistent with weak quartzite flow laws, but inconsistent with strong ones. In Chapter 5 I show that measurements of dynamic stress from pseudotachylites, are within error of measurements of static stress from brittle-to-ductile shear zones, suggesting that the formation of melt along the fault may have triggered seismic arrest, rather than lubrication. Chapter 6 is a methods chapter demonstrating that NIST 6XX glass standards can be used to quantify the Ti contents of quartz if the matrix effect between these glasses and nearly pure quartz can be corrected.</p> <div class="credits"> <p class="dwt_author">Behr, Whitney Maria</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">31</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..14.6051R"> <span id="translatedtitle">Linking <span class="hlt">continental</span> drift, <span class="hlt">plate</span> tectonics and the thermal state of the Earth's mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Continents slowly drift at the top of the mantle, undergoing episodic events like collision, aggregation or splitting. <span class="hlt">Continental</span> drift and oceanic <span class="hlt">plate</span> tectonics are surface expressions of mantle convection and closely linked to the thermal state of the mantle. In the present study we will present a number of 3D spherical numerical simulations of mantle convection with self-consistently generated <span class="hlt">plates</span> and compositionally and rheologically-distinct continents floating at the top of the mantle. We will focus on the question of how <span class="hlt">continental</span> drift, oceanic <span class="hlt">plate</span> tectonics and the thermal state of the Earth's mantle are linked, by using different continent configurations ranging from one supercontinent to six small continents. With a supercontinent present we find a strong time-dependence of the oceanic surface heat flow and suboceanic mantle temperature, driven by the generation of new <span class="hlt">plate</span> boundaries. Very large oceanic <span class="hlt">plates</span> correlate with periods of hot suboceanic mantle, while the mantle below smaller oceanic <span class="hlt">plates</span> tends to be colder. Temperature fluctuations of subcontinental mantle are significantly smaller than in oceanic regions and caused by a time-variable efficiency of thermal insulation of the <span class="hlt">continental</span> convection cell. With multiple continents present the temperature below individual continents is generally lower than below a supercontinent and is more time-dependent, with fluctuations as large as 15% that may be caused by <span class="hlt">continental</span> assembly and dispersal. The periods of hot subcontinental mantle correlate with strong clustering of the continents and periods of cold subcontinental mantle, at which it can even be colder than suboceanic mantle, with a more dispersed continent configuration. Our findings with multiple continents imply that periods of partial melting and strong magmatic activity inside the continents, which may contribute to <span class="hlt">continental</span> rifting and pronounced growth of <span class="hlt">continental</span> crust, might be episodic processes related to the supercontinent cycle [Rolf et al., submitted]. In a further step we will investigate the effects of the mantle Rayleigh number, heating mode (internal versus basal heating), yield strength of the lithosphere and a depth-dependent viscosity structure of the mantle. Reference: Rolf, T., Coltice, N. and Tackley, P.J., Linking <span class="hlt">continental</span> drift, <span class="hlt">plate</span> tectonics and the thermal state of the Earth's mantle, submitted to Earth Planet Science Letters</p> <div class="credits"> <p class="dwt_author">Rolf, T.; Coltice, N.; Tackley, P. J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">32</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42040444"> <span id="translatedtitle">How does <span class="hlt">plate</span> coupling affect crustal stresses in Northeast and Southwest Japan?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Plate</span> subduction causes compression of the <span class="hlt">continental</span> crust in Northeast (NE) Japan but not in Southwest (SW) Japan. We propose that the different effects are both consistent with weak subduction faults, of which the static shear stress is described using an effective coefficient of friction mu'. Stresses in the <span class="hlt">overriding</span> <span class="hlt">plate</span> are controlled by two competing factors, the <span class="hlt">plate</span> coupling</p> <div class="credits"> <p class="dwt_author">Kelin Wang; Kiyoshi Suyehiro</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">33</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/19668573"> <span id="translatedtitle"><span class="hlt">Overriding</span> of the preseptal orbicularis oculi muscle in Caucasian cadavers.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">We aimed to microscopically examine whether Caucasian eyelids demonstrate <span class="hlt">overriding</span> of preseptal orbicularis oculi muscle (OOM) over the pretarsal OOM in both lower and upper eyelids. Full thickness sections of 13 lower eyelids and 11 upper eyelids from seven Caucasian cadavers were examined. In the lower eyelids, all 13 specimens demonstrated clear <span class="hlt">overriding</span> of preseptal OOM over the pretarsal OOM. The <span class="hlt">overriding</span> part extended almost to the level of lower eyelid margin. However, in the upper eyelids, only one of the 11 eyelids demonstrated <span class="hlt">overriding</span>, and the <span class="hlt">overriding</span> part only extended to the level of mid-tarsal <span class="hlt">plate</span>. Our result strongly supports the hypothesis of <span class="hlt">overriding</span> of the preseptal OOM over the pretarsal OOM as an etiology of involutional lower eyelid entropion. The relatively low frequency of upper eyelid <span class="hlt">overriding</span> preseptal OOM in our study reflects and may explain the rare occurrence of involutional upper eyelid entropion. PMID:19668573</p> <div class="credits"> <p class="dwt_author">Kakizaki, Hirohiko; Chan, Weng Onn; Takahashi, Yasuhiro; Selva, Dinesh</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-06-02</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">34</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2708989"> <span id="translatedtitle"><span class="hlt">Overriding</span> of the preseptal orbicularis oculi muscle in Caucasian cadavers</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">We aimed to microscopically examine whether Caucasian eyelids demonstrate <span class="hlt">overriding</span> of preseptal orbicularis oculi muscle (OOM) over the pretarsal OOM in both lower and upper eyelids. Full thickness sections of 13 lower eyelids and 11 upper eyelids from seven Caucasian cadavers were examined. In the lower eyelids, all 13 specimens demonstrated clear <span class="hlt">overriding</span> of preseptal OOM over the pretarsal OOM. The <span class="hlt">overriding</span> part extended almost to the level of lower eyelid margin. However, in the upper eyelids, only one of the 11 eyelids demonstrated <span class="hlt">overriding</span>, and the <span class="hlt">overriding</span> part only extended to the level of mid-tarsal <span class="hlt">plate</span>. Our result strongly supports the hypothesis of <span class="hlt">overriding</span> of the preseptal OOM over the pretarsal OOM as an etiology of involutional lower eyelid entropion. The relatively low frequency of upper eyelid <span class="hlt">overriding</span> preseptal OOM in our study reflects and may explain the rare occurrence of involutional upper eyelid entropion.</p> <div class="credits"> <p class="dwt_author">Kakizaki, Hirohiko; Chan, Weng Onn; Takahashi, Yasuhiro; Selva, Dinesh</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">35</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/655513"> <span id="translatedtitle">Role of <span class="hlt">plate</span> kinematics and <span class="hlt">plate</span>-slip-vector partitioning in <span class="hlt">continental</span> magmatic arcs: Evidence from the Cordillera Blanca, Peru</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">New structural and geochronological data from the Cordillera Blanca batholith in the Peruvian Andes, coupled with Nazca-South American <span class="hlt">plate</span>-slip-vector data, indicate that oblique convergence and associated strike-slip partitioning strongly influenced <span class="hlt">continental</span> magmatic arc evolution. Both the strain field and mode of magmatism (plutonism vs. volcanism) in the late Miocene Peruvian Andes were controlled by the degree to which the arc-parallel component of the <span class="hlt">plate</span> slip vector was partitioned into the arc. Strong strike-slip partitioning at ca. 8 Ma produced arc-parallel sinistral shear, strike-slip intercordilleran basins and east-west-oriented tension fractures that facilitated emplacement of the Cordillera Blanca batholith (ca. 8.2 {+-} 0.2 Ma). Periods during which the strike-slip component was not partitioned into the arc (ca. 10 and ca. 7 Ma) were associated with roughly arc-normal contraction and ignimbrite volcanism. The data thus support the contention that contraction within <span class="hlt">continental</span> magmatic arcs favors volcanism, whereas transcurrent shear favors plutonism. The tie between oblique convergence and batholith emplacement in late Miocene Peruvian Andes provides a modern analogue for batholiths emplaced as the result of transcurrent shear in ancient arcs.</p> <div class="credits"> <p class="dwt_author">McNulty, B.A. [California State Univ., Carson, CA (United States). Dept. of Earth Sciences; Farber, D.L. [Lawrence Livermore National Lab., CA (United States). Inst. of Geophysics and Planetary Physics; Wallace, G.S.; Lopez, R. [Univ. of California, Santa Cruz, CA (United States). Earth Science Dept.; Palacios, O. [Inst. de Geologico Minero y Metalurgico, Lima (Peru)</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-09-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">36</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6421776"> <span id="translatedtitle">Gulf of Mexico <span class="hlt">plate</span> reconstruction by palinspastic restoration of extended <span class="hlt">continental</span> crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">In this study, total tectonic subsidence analysis was used to estimate the mount of crust extension in the Gulf of Mexico to determine its effects on the proposed <span class="hlt">plate</span> reconstructions. This involves the calculation and mapping of the sediment-unloaded-basement depth from observations of the basement depth, water depth, and sediment compaction properties. The well-known depth-age relation for oceanic crust and a model for the subsidence of extended <span class="hlt">continental</span> crust allowed within the limits of available data the identification and mapping of crust type and the amount of extension of transitional crust. The zone of extended <span class="hlt">continental</span> crust under the northern margin of the Gulf is extraordinarily wide, more than 800 km (500 mi) in a cross section through east Texas. The zone of extended crust to the south is much narrower, about 150 km (90 mi) on the margin of the Yucatan Block. Palinspastic restoration shows that the total 950 km (590 mi) of extended and thinned <span class="hlt">continental</span> crust corresponds to 490 km (300 mi) of <span class="hlt">continental</span> crust of original thickness. Therefore 460 km (280 mi) of crustal extension occurred during rifting and prior to ocean crust formation. The 460 km (280 mi) of extension along this cross section, and the results of similar calculations on the other cross sections, must be accounted for properly when reconstructing the prerift configuration of the Gulf of Mexico.</p> <div class="credits"> <p class="dwt_author">Sawyer, D.S.</p> <p class="dwt_publisher"></p> <p class="publishDate">1984-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">37</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://eric.ed.gov/?q=%22Earth+magnetic+field%22&id=EJ557421"> <span id="translatedtitle">Misconceptions and Conceptual Changes Concerning <span class="hlt">Continental</span> Drift and <span class="hlt">Plate</span> Tectonics among Portuguese Students Aged 16-17.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">|This study investigates student misconceptions in the areas of continent, ocean, permanence of ocean basins, <span class="hlt">continental</span> drift, Earth's magnetic field, and <span class="hlt">plates</span> and <span class="hlt">plate</span> motions. A teaching-learning model was designed based on a constructivist approach. Results show that students held a substantial number of misconceptions. (Author/DKM)|</p> <div class="credits"> <p class="dwt_author">Marques, Luis; Thompson, David</p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">38</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T23B2255L"> <span id="translatedtitle">The differ respond of China <span class="hlt">continental</span> to the collision between Eurasian and Philippine Sea <span class="hlt">plate</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The southeastern margin of China <span class="hlt">continental</span> is one of ideal area to study modern <span class="hlt">plate</span> interaction. This area most attract geologists attention is largely covered by widely distributed late Mesozoic igneous rocks. In the past decades many studies focus on the relations of the collision between the Philippine Sea <span class="hlt">plate</span> and the Eurasian <span class="hlt">plate</span> in the east of Taiwan region based on geological and geophysical data. In the recent decades the globe or large regional passive and active source seismic images proposed a fine geometry model in which the crust present gradually thinning from inner continent to southeastern margin. This is regarded as evidence of the southeastern margin of China <span class="hlt">continental</span> —Eurasian <span class="hlt">plate</span> respond to the collision over against the Taiwan Strait. Relatively the partition feature—the Model if there is difference and how to vary across margin of mainland, still remains poorly defined. In this study, the data recorded by 20 flexible broadband stations deployed onshore along the margin of main <span class="hlt">continental</span> in Fujian province from 2008 to 2010 and 130 permanent stations of New China Digital Seismology Network (NCDSN), was combined used. And totally 16664 reliable receiver functions were obtained for imaging the structure of the crust and upper mantle beneath the stations array. Only visually comparison, we find the receiver functions are evident different for teleseismic events between the station located at the southwest and the northeast of Fujian province. After the auto-searching algorithm, H-k method, which sums the amplitudes of the receiver functions at the predicted arrival times of Ps and its multiple phases, has been used to determine the best estimations of crustal thickness (H) and VP/VS ratio (k). The preliminary result show that crustal thicknesses stepwise vary from 33-36,32-30 to 29-27km in average north to south, that is a poignant contras with northeastward surface tectonic.the subordinate characteristic, there seems is a Moho ditch can be tracing from about longitude 118 degree from north to south. An obvious limitation of depth level range appears around latitude 26 degree. This result is helpful for explain why there is stronger earthquake activity and much geothermal resource the southwestern than northeastern of Fujian, China.</p> <div class="credits"> <p class="dwt_author">Li, Q.; Gao, R.; He, C.; Guan, Y.; Li, W.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">39</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010GGG....11.5006D"> <span id="translatedtitle">Origin of volcanic seamounts at the <span class="hlt">continental</span> margin of California related to changes in <span class="hlt">plate</span> margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Volcanic samples collected with the Monterey Bay Aquarium Research Institute's ROV Tiburon from eight seamounts at the <span class="hlt">continental</span> margin offshore central to southern California comprise a diverse suite of mainly alkalic basalt to trachyte but also include rare tholeiitic basalt and basanite. All samples experienced complex crystal fractionation probably near the crust/mantle boundary, based on the presence in some of mantle xenoliths. Incompatible trace elements, poorly correlated with isotopic compositions, suggest variable degrees of partial melting of compositionally heterogeneous mantle sources, ranging from MORB-like to relatively enriched OIB. High-precision 40Ar/39Ar ages indicate episodes of volcanic activity mainly from 16 to 7 Ma but document one eruption as recent as 2.8 Ma at San Juan Seamount. Synchronous episodes of volcanism occurred at geographically widely separated locations offshore and within the <span class="hlt">continental</span> borderland. Collectively, the samples from these seamounts have age ranges and chemical compositions similar to those from Davidson Seamount, identified as being located atop an abandoned spreading center. These seamounts appear to have a common origin ultimately related to abandonment and partial subduction of spreading center segments when the <span class="hlt">plate</span> boundary changed from subduction-dominated to a transform margin. They differ in composition, age, and origin from other more widespread near-ridge seamounts, which commonly have circular plans with nested calderas, and from age progressive volcanoes in linear arrays, such as the Fieberling-Guadalupe chain, that occur in the same region. Each volcanic episode represents decompression melting of discrete enriched material in the suboceanic mantle with melts rising along zones of weakness in the oceanic crust fabric. The process may be aided by transtensional tectonics related to continued faulting along the <span class="hlt">continental</span> margin.</p> <div class="credits"> <p class="dwt_author">Davis, A. S.; Clague, D. A.; Paduan, J. B.; Cousens, B. L.; Huard, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">40</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T31F..04N"> <span id="translatedtitle">Large vertical motions and basin evolution in the Outer <span class="hlt">Continental</span> Borderland off Southern California associated with <span class="hlt">plate</span> boundary development and <span class="hlt">continental</span> rifting</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The <span class="hlt">Continental</span> Borderland offshore southern California occupies a strategic position along the <span class="hlt">continental</span> margin. It was the locus of ~75% of Pacific-North America displacement history, it helped accommodate the large-scale (>90°) tectonic rotation of the Western Transverse Ranges province, and is still accommodating potentially 20% of PAC-NAM <span class="hlt">plate</span> motion today. As such, it represents an ideal natural laboratory to investigate <span class="hlt">plate</span> boundary evolution and basin development associated with transform initiation, oblique <span class="hlt">continental</span> rifting, transrotation and transpression. We have been using newly released grids of high-quality industry multichannel seismic (MCS) reflection data, combined with multibeam bathymetry and offshore well data to map and construct digital 3D fault surfaces and stratigraphic reference horizons over large parts of the Outer <span class="hlt">Continental</span> Borderland. These 3D surfaces of structure and stratigraphy can be used to better understand and evaluate regional patterns of uplift, subsidence, fault interaction and other aspects of <span class="hlt">plate</span> boundary deformation. In the northern Outer Borderland, mapping in Santa Cruz basin, and across both Santa Rosa and Santa Cruz-Catalina ridges reveals a pattern of interacting high-and low-angle faults, fault reactivation, basin subsidence, folding, and basin inversion. Subsidence since early-Miocene time is significant (up to 4 km) and is much larger than predicted by simple thermal cooling models of <span class="hlt">continental</span> rifting. This requires additional tectonic components to drive this regional subsidence and subsequent basin inversion. Farther south, a more en echelon pattern of ridges and basins suggests a distributed component of right-lateral shear also contributed to much of the modern Borderland seafloor topography, including major Borderland basins. Vertical motions of uplift and subsidence can be estimated from a prominent early-Miocene unconformity that likely represents a regional, paleo-horizontal, near-paleo-sea-level erosional surface. As such, this paleo-reference datum can be used to reconstruct Borderland forearc basin geometry prior to rifting, subsidence and subsequent basin inversion. Although not well resolved, the age of the regional unconformity appears to be time transgressive, and tends to young to the east and south. This progression may thus correlate with the oblique subduction of the Pacific-Arguello spreading ridge, rather than the onset of later <span class="hlt">continental</span> rifting, as rifting in the Borderland typically progressed to the north and west following each jump in the triple junction farther south. This sequence of: 1) a regional unconformity requiring uplift, 2) followed by subsidence, and 3) later basin inversion to form ridges thus documents an unusual and unexpected pattern of vertical motion reversal associated with the initiation of a predominantly strike-slip PAC-NAM <span class="hlt">plate</span> boundary.</p> <div class="credits"> <p class="dwt_author">Nicholson, C.; Sorlien, C. C.; Schindler, C. S.; De Hoogh, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_1");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a style="font-weight: bold;">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_3");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_2 div --> <div id="page_3" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_2");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a style="font-weight: bold;">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_4");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">41</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010ESRv..101...29S"> <span id="translatedtitle"><span class="hlt">Continental</span> lithosphere of the Arabian <span class="hlt">Plate</span>: A geologic, petrologic, and geophysical synthesis</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Arabian <span class="hlt">Plate</span> originated ˜ 25 Ma ago by rifting of NE Africa to form the Gulf of Aden and Red Sea. It is one of the smaller and younger of the Earth's lithospheric <span class="hlt">plates</span>. The upper part of its crust consists of crystalline Precambrian basement, Phanerozoic sedimentary cover as much as 10 km thick, and Cenozoic flood basalt (harrat). The distribution of these rocks and variations in elevation across the <span class="hlt">Plate</span> cause a pronounced geologic and topographic asymmetry, with extensive basement exposures (the Arabian Shield) and elevations of as much as 3000 m in the west, and a Phanerozoic succession (Arabian Platform) that thickens, and a surface that descends to sea level, eastward between the Shield and the northeastern margin of the <span class="hlt">Plate</span>. This tilt in the <span class="hlt">Plate</span> is partly the result of marginal uplift during rifting in the south and west, and loading during collision with, and subduction beneath, the Eurasian <span class="hlt">Plate</span> in the northeast. But a variety of evidence suggests that the asymmetry also reflects a fundamental crustal and mantle heterogeneity in the <span class="hlt">Plate</span> that dates from Neoproterozoic time when the crust formed. The bulk of the <span class="hlt">Plate</span>'s upper crystalline crust is Neoproterozoic in age (1000-540 Ma) reflecting, in the west, a 300-million year process of <span class="hlt">continental</span> crustal growth between ˜ 850 and 550 Ma represented by amalgamated juvenile magmatic arcs, post-amalgamation sedimentary and volcanic basins, and granitoid intrusions that make up as much as 50% of the Shield's surface. Locally, Archean and Paleoproterozoic rocks are structurally intercalated with the juvenile Neoproterozoic rocks in the southern and eastern parts of the Shield. The geologic dataset for the age, composition, and origin of the upper crust of the <span class="hlt">Plate</span> in the east is smaller than the database for the Shield, and conclusions made about the crust in the east are correspondingly less definitive. In the absence of exposures, furthermore, nothing is known by direct observation about the composition of the crust north of the Shield. Nonetheless, available data indicate a geologic history for eastern Arabian crust different to that in the west. The Neoproterozic crust (˜ 815-785 Ma) is somewhat older than in the bulk of the Arabian Shield, and igneous and metamorphic activity was largely finished by 750 Ma. Thereafter, the eastern part of the <span class="hlt">Plate</span> became the site of virtually continuous sedimentation from 725 Ma on and into the Phanerozoic. This implies that a relatively strong lithosphere was in place beneath eastern Arabia by 700 Ma in contrast to a lithospheric instability that persisted to ˜ 550 Ma in the west. Lithospheric differentiation is further indicated by the Phanerozoic depositional history with steady subsidence and accumulation of a sedimentary succession 5-14 km thick in the east and a consistent high-stand and thin to no Phanerozoic accumulation over the Shield. Geophysical data likewise indicate east-west lithospheric differentiation. Overall, the crustal thickness of the <span class="hlt">Plate</span> (depth to the Moho) is ˜ 40 km, but there is a tendency for the crust to thicken eastward by as much as 10% from 35-40 km beneath the Shield to 40-45 km beneath eastern Arabia. The crust also becomes structurally more complex with as many as 5 seismically recognized layers in the east compared to 3 layers in the west. A coincident increase in velocity is noted in the upper-crust layers. Complementary changes are evidenced in some models of the Arabian <span class="hlt">Plate</span> <span class="hlt">continental</span> upper mantle, indicating eastward thickening of the lithospheric mantle from ˜ 80 km beneath the Shield to ˜ 120 km beneath the Platform, which corresponds to an overall lithospheric thickening (crust and upper mantle) from ˜ 120 km to ˜ 160 km eastward. The locus of these changes coincides with a prominent magnetic anomaly (Central Arabian Magnetic Anomaly, CAMA) in the extreme eastern part of the Arabian Shield that extends north across the north-central part of the Arabian <span class="hlt">Plate</span>. The CAMA also coincides with a major structural boundary separating a region of northerly and northwes</p> <div class="credits"> <p class="dwt_author">Stern, Robert J.; Johnson, Peter</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-07-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">42</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.T11F..01F"> <span id="translatedtitle">Development of the New Zealand and San Andreas <span class="hlt">Continental</span> Transforms: From <span class="hlt">Plate</span> Kinematics to Lithospheric Geodynamics (Invited)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Although oftentimes compared as being two similar <span class="hlt">continental</span> transforms, the development of the San Andreas and Alpine Fault <span class="hlt">plate</span> boundary systems reflect two distinctly different geodynamic paths to formation, localization, and evolution. Characteristics that lead to fundamental differences in their present-day tectonic behavior. The San Andreas system has formed in response to the migration of two triple junctions, and it lengthens over time at these transitions from subduction to translation. The San Andreas system forms within the region of thin lithosphere left in the wake of slab removal or subduction cessation, and therefore thermal processes dominate in the development of a localized <span class="hlt">plate</span> boundary. There are associated short-lived deformational events including significant crustal thickening and subsequent crustal thinning that serve to substantially modify the overlying North American crust during this 3-5 million year transition time. In contrast the development of the Alpine Fault <span class="hlt">plate</span> boundary system through New Zealand follows a different geodynamic path, and this transform boundary reflects an intermediate point in the overall transition of that Australia-Pacific <span class="hlt">plate</span> boundary through New Zealand from an extensional to convergent boundary. Since approximately 25 Ma, with rapid changes in Australia-Pacific <span class="hlt">plate</span> interactions, the <span class="hlt">plate</span> boundary structure through <span class="hlt">continental</span> New Zealand rapidly changed from extensional to translation/transpression. This transpression was accommodated by the initiation of two subduction regimes, whose positions were controlled by continent-ocean transitions linked by the translational/transpressional (proto) Alpine Fault system. This trench-transform-trench <span class="hlt">plate</span> boundary system has migrated southward, maintaining essentially a constant length, but not constant localization, and along the way, ephemerally incorporating segments of the Australia and Pacific <span class="hlt">plates</span> into the boundary - modifying, exhuming, and removing lithosphere. In spite of some present kinematic similarities, the history and ongoing tectonic evolution of these two prototypical <span class="hlt">continental</span> transforms demonstrates the importance of the tectonic pathway to the development of a <span class="hlt">plate</span> boundary and provides critical constraints on using these boundaries to understand fundamental <span class="hlt">plate</span> boundary processes.</p> <div class="credits"> <p class="dwt_author">Furlong, K. P.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">43</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012JGRB..117.8403T"> <span id="translatedtitle">Geodynamic models of terrane accretion: Testing the fate of island arcs, oceanic plateaus, and <span class="hlt">continental</span> fragments in subduction zones</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Crustal growth at convergent margins can occur by the accretion of future allochthonous terranes (FATs), such as island arcs, oceanic plateaus, submarine ridges, and <span class="hlt">continental</span> fragments. Using geodynamic numerical experiments, we demonstrate how crustal properties of FATs impact the amount of FAT crust that is accreted or subducted, the type of accretionary process, and the style of deformation on the <span class="hlt">overriding</span> <span class="hlt">plate</span>. Our results show that (1) accretion of crustal units occurs when there is a weak detachment layer within the FAT, (2) the depth of detachment controls the amount of crust accreted onto the <span class="hlt">overriding</span> <span class="hlt">plate</span>, and (3) lithospheric buoyancy does not prevent FAT subduction during constant convergence. Island arcs, oceanic plateaus, and <span class="hlt">continental</span> fragments will completely subduct, despite having buoyant lithospheric densities, if they have rheologically strong crusts. Weak basal layers, representing pre-existing weaknesses or detachment layers, will either lead to underplating of faulted blocks of FAT crust to the <span class="hlt">overriding</span> <span class="hlt">plate</span> or collision and suturing of an unbroken FAT crust. Our experiments show that the weak, ultramafic layer found at the base of island arcs and oceanic plateaus plays a significant role in terrane accretion. The different types of accretionary processes also affect deformation and uplift patterns in the <span class="hlt">overriding</span> <span class="hlt">plate</span>, trench migration and jumping, and the dip of the <span class="hlt">plate</span> interface. The resulting accreted terranes produced from our numerical experiments resemble observed accreted terranes, such as the Wrangellia Terrane and Klamath Mountain terranes in the North American Cordilleran Belt.</p> <div class="credits"> <p class="dwt_author">Tetreault, J. L.; Buiter, S. J. H.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">44</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40447673"> <span id="translatedtitle"><span class="hlt">Continental</span> fragmentation along the South Scotia Ridge transcurrent <span class="hlt">plate</span> boundary (NE Antarctic Peninsula)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The study of the South Scotia Ridge on the basis of swath bathymetry, multichannel seismic and magnetometry profiles, obtained during the HESANT92\\/93 cruise and complemented with satellite gravimetry and seismicity data illustrates the tectonics of the region. The thinned <span class="hlt">continental</span> crust fragments of the ridge are bounded by oceanic crust of the Scotia Sea to the North and Powell Basin</p> <div class="credits"> <p class="dwt_author">J. Galindo-Zaldívar; A. Jabaloy; A. Maldonado; C. Sanz de Galdeano</p> <p class="dwt_publisher"></p> <p class="publishDate">1996-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">45</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/41055563"> <span id="translatedtitle"><span class="hlt">Continental</span> lithosphere of the Arabian <span class="hlt">Plate</span>: A geologic, petrologic, and geophysical synthesis</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The Arabian <span class="hlt">Plate</span> originated ?25Ma ago by rifting of NE Africa to form the Gulf of Aden and Red Sea. It is one of the smaller and younger of the Earth's lithospheric <span class="hlt">plates</span>. The upper part of its crust consists of crystalline Precambrian basement, Phanerozoic sedimentary cover as much as 10km thick, and Cenozoic flood basalt (harrat). The distribution of</p> <div class="credits"> <p class="dwt_author">Robert J. Stern; Peter Johnson</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">46</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51258528"> <span id="translatedtitle">The influence of <span class="hlt">continental</span> roots and asthenospheric viscosity on <span class="hlt">plate</span>-mantle coupling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Viscous flow in the mantle exerts shear tractions on the base of the Earth's rigid lithosphere. These shear tractions contribute to the crustal deformation and tectonic <span class="hlt">plate</span> motions that we observe at the Earth's surface, but their influence depends on how mantle flow couples to the <span class="hlt">plates</span>. There are two rheological controls that are thought to exert a primary influence</p> <div class="credits"> <p class="dwt_author">C. P. Conrad; C. Lithgow-Bertelloni</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">47</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/56382282"> <span id="translatedtitle"><span class="hlt">Plate</span> Boundary Forces at Subduction Zones: Effects of <span class="hlt">Plate</span> Bending and Back-Arc Orogeny on Global <span class="hlt">Plate</span> Motions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Deformation of both subducting and <span class="hlt">overriding</span> at convergent <span class="hlt">plate</span> boundaries tends to dissipate energy that would otherwise be used to drive <span class="hlt">plate</span> motions. For subducting <span class="hlt">plates</span>, the magnitude of the bending deformation is not known because of poor constraints on slab strength. For <span class="hlt">overriding</span> <span class="hlt">plates</span>, back-arc orogeny results from upper <span class="hlt">plate</span> shortening and frictional stresses on the <span class="hlt">plate</span> interface that</p> <div class="credits"> <p class="dwt_author">C. P. Conrad; B. J. Meade; B. Wu; A. Heuret; C. Lithgow-Bertelloni; S. Lallemand</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">48</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.springerlink.com/index/p105885153np6788.pdf"> <span id="translatedtitle"><span class="hlt">Continental</span> Collision and the STEP-wise Evolution of Convergent <span class="hlt">Plate</span> Boundaries: From Structure to Dynamics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Particularly interesting stages in the evolution of subduction zones are the two main transient stages: initiation and termination.\\u000a In this contribution the focus is on the second of these: terminal stage subduction, often triggered by <span class="hlt">continental</span> collision\\u000a or arc-continent collision. The landlocked basin setting of the Mediterranean region, in particular the western-central Mediterranean,\\u000a provides unique opportunities to study terminal stage</p> <div class="credits"> <p class="dwt_author">Rinus Wortel; Rob Govers; Wim Spakman</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">49</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUSM.G21B..01H"> <span id="translatedtitle">Estimates of <span class="hlt">Continental</span> <span class="hlt">Plate</span> Motions Derived From Continuous GPS Measurements of Station Coordinates and Velocities, 1996-2004</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Analysis Centres of the International GPS Service (IGS) currently compute daily Earth Rotation Parameters (ERPs) and weekly precise coordinates for over 200 globally distributed tracking stations. These estimates are made available to the scientific community in the Solution Independent Exchange (SINEX) format, developed for exchange and analysis of position estimates from techniques such as SLR, LLR, VLBI, DORIS and GPS. On behalf of the IGS, National Resources Canada (NRCan) has been combining, officially since 1999, all weekly SINEX files from the ACs to form weekly and cumulative solutions. The weekly solution (named igsyyPwwww, yy = 2-digit year, wwww = 4-digit GPS week) contains estimates of station coordinates, ERPs and geocentre pertaining to the GPS week, and the cumulative solution (named IGSyyPWW, WW = 2-digit week number, 01 to 52, within the year) comprises station coordinates and velocities in a common reference epoch, Jan. 1, 1998. For example, two solutions produced for week 1253 (2nd week of year 2004) were igs04P1253 (weekly) and IGS04P02 (cumulative). Since week 1253, all IGS solutions have been aligned to IGb00, a realization of IGS's most recent International Terrestrial Reference Frame, ITRF2000. IGb00 was obtained from coordinates and velocities of 99 globally distributed reference stations by alignment to ITRF2000 at GPS week 1231 of cumulative solution IGS03P33. Before week 1143, a realization of IGS's previous reference frame, ITRF97, was used instead. Using the cumulative solution from any given week, the rotation components of any <span class="hlt">continental</span> <span class="hlt">plate</span> with at least two stations are estimated and compared with published results. These include three known <span class="hlt">plate</span> models: NNR NUVEL 1, NNR NUVEL 1A and the most recent REVEL 2000 aligned to ITRF97. The findings can be summarized as follows: <span class="hlt">Continental</span> rotations derived from IGS04P02 are shown to be significantly different at 99% confidence level from NNR NUVEL 1A's estimates for North American, Eurasian, Australian, Pacific, Antarctic, Indian, Nazca and Nubian (the latter compared to NNR NUVEL 1A African) <span class="hlt">plates</span>. In addition, certain <span class="hlt">plates</span> previously regarded as belonging to an adjacent, larger continent in NNR NUVEL 1 or 1A are now seen to move significantly differently; e.g., Amurian distinct from Eurasian, Adriatic and Sinai distinct from NNR NUVEL 1A African. North American, Eurasian, Australian and Pacific <span class="hlt">plates</span> show significantly different rotations in IGS04P02 than predicted by REVEL 2000, yet not from the alignment of REVEL 2000 to IGb00. Certain pairs of adjacent <span class="hlt">plates</span> show relative Euler poles near their <span class="hlt">plate</span> boundaries; e.g., Eurasian and North American, Amurian and Eurasian, Amurian and South-China, Adriatic and Eurasian, Arabian and Nubian, Sinai and Nubian, Sinai and Arabian, Nubian and Somali. This phenomenon can be expected when bordering <span class="hlt">plates</span> show no subduction or obduction. RMS difference between velocities of stations used in Euler pole calculation in IGS04P02 and those expected from NNR NUVEL 1A rise to 4.3 mm/yr in the horizontal component and 8.7 mm/yr in the vertical. The horizontal RMS velocity difference decreases significantly to 2.4 mm/yr when IGS04P02 is compared with REVEL 2000.</p> <div class="credits"> <p class="dwt_author">Hutchison, D. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">50</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/53082871"> <span id="translatedtitle">Dynamic Development of the Europe\\/Adria <span class="hlt">Plate</span> Boundary During the Transition from Oceanic Subduction to <span class="hlt">Continental</span> Collision in the Northern Apennines: a Case History for Subduction Erosion</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">In the Northern Apennines the dynamic of the margin frontal wedge during the Oligo-Miocene transition from oceanic subduction to <span class="hlt">continental</span> collision is preserved in a chaotic complex called the Sestola Vidiciatico Unit. There, oceanic sedimentary rocks accreted and deformed within the Late Cretaceous to Late Eocene accretionary prism have been successively involved in the <span class="hlt">plate</span> boundary through underthrusting in a</p> <div class="credits"> <p class="dwt_author">G. Bettelli; P. Vannucchi; F. Remitti</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">51</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.soest.hawaii.edu/GG/FACULTY/conrad/papers/Conrad_GRL2006.pdf"> <span id="translatedtitle">Influence of <span class="hlt">continental</span> roots and asthenosphere on <span class="hlt">plate</span>-mantle coupling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The shear tractions that mantle flow exerts on the base of Earth's lithosphere contribute to <span class="hlt">plate</span>-driving forces and lithospheric stresses. We investigate the sensitivity of these tractions to sub-lithospheric viscosity variations by comparing shear tractions computed from a mantle flow model featuring laterally-varying lithosphere and asthenosphere viscosity with those from a model with layered viscosity. Lateral viscosity variations generally do</p> <div class="credits"> <p class="dwt_author">Clinton P. Conrad; Carolina Lithgow-Bertelloni</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">52</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012DokES.442..220Z"> <span id="translatedtitle">The ancient <span class="hlt">continental</span> margins of the North American and South American <span class="hlt">plates</span> and regularities in the occurrence of oil and gas accumulations in them</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Various stages of the development of sedimentary basins along the ancient margins of the North American and South American <span class="hlt">plates</span> are considered. It is shown that the potential of the oil-and-gas bearing is related to a certain stage of evolution of the basins. For the margins of the North American <span class="hlt">plate</span>, it is the first stage of development in the structure of the ancient Paleozoic <span class="hlt">continental</span> margins that developed under passive tectonic conditions. For the basins along the ancient margins of the South American <span class="hlt">plate</span>, it is the second stage, which is the stage of the formation and development of foredeeps overlaid on the earlier structures. An interesting regularity is displayed: than younger the folding-mountain structures that originated in the distal parts of the <span class="hlt">continental</span> margins, than greater the age range of source rocks in the sedimentary basins preserved there.</p> <div class="credits"> <p class="dwt_author">Zabanbark, A.; Lobkovskii, L. I.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">53</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012JGRB..117.5403T"> <span id="translatedtitle">Dynamic models of interseismic deformation and stress transfer from <span class="hlt">plate</span> motion to <span class="hlt">continental</span> transform faults</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We present numerical models of earthquake cycles on a strike-slip fault that incorporate laboratory-derived power law rheologies with Arrhenius temperature dependence, viscous dissipation, conductive heat transfer, and far-field loading due to relative <span class="hlt">plate</span> motion. We use these models to explore the evolution of stress, strain, and thermal regime on "geologic" timescales (˜106-107 years), as well as on timescales of the order of the earthquake recurrence (˜102 years). Strain localization in the viscoelastic medium results from thermomechanical coupling and power law dependence of strain rate on stress. For conditions corresponding to the San Andreas fault (SAF), the predicted width of the shear zone in the lower crust is ˜3-5 km; this shear zone accommodates more than 50% of the far-field <span class="hlt">plate</span> motion. Coupled thermomechanical models predict a single-layer lithosphere in case of "dry" composition of the lower crust and upper mantle, and a "jelly sandwich" lithosphere in case of "wet" composition. Deviatoric stress in the lithosphere in our models is relatively insensitive to the water content, the far-field loading rate, and the fault strength and is of the order of 102 MPa. Thermomechanical coupling gives rise to an inverse correlation between the fault slip rate and the ductile strength of the lithosphere. We show that our models are broadly consistent with geodetic and heat flow constrains from the SAF in Northern California. Models suggest that the regionally elevated heat flow around the SAF may be at least in part due to viscous dissipation in the ductile part of the lithosphere.</p> <div class="credits"> <p class="dwt_author">Takeuchi, Christopher S.; Fialko, Yuri</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">54</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T13I..03M"> <span id="translatedtitle">Relation of <span class="hlt">plate</span> kinematic parameters to deformation along the Andean margin from Late Jurassic to the present</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The geological consequences of temporal and spatial changes in subduction along the Andean margin from 170 Ma to the present were investigated in the context of a recently developed, global <span class="hlt">plate</span> kinematic model. Geological events recorded by the <span class="hlt">overriding</span> <span class="hlt">continental</span> <span class="hlt">plate</span>, including the development of extensional basins, orogeny and crustal growth accompanied by thickening and/or magmatism, were contrasted with the age of the subducting oceanic slab(s), the absolute <span class="hlt">plate</span> velocity of South America both normal and parallel to the trench, and the relative convergence velocity between South America and the subducting slab(s) both normal and parallel to the trench. Preliminary results indicate that the absolute velocity of the <span class="hlt">overriding</span> <span class="hlt">plate</span> is strongly correlated with the extent of crustal extension; the development of marginal basins floored by oceanic crust occurred only when the absolute <span class="hlt">plate</span> velocity of South America was directed away from the trench. This condition did not accompany the development of aborted marginal basins. An abrupt increase in relative convergence rates between the South American continent and the subducting slab also often accompanied the initiation of extension in the <span class="hlt">overriding</span> <span class="hlt">plate</span>. However, high convergence rates primarily accompanied the development of fold and thrust belts, and were linked with plateau uplift. Inter-dependencies between the various parameters are investigated to build a more complete model of conditions necessary for the development of significant geological events along <span class="hlt">continental</span> margins controlled by subduction.</p> <div class="credits"> <p class="dwt_author">Maloney, K. T.; Clarke, G. L.; Quevedo, L. E.; Klepeis, K. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">55</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54919608"> <span id="translatedtitle">Evolution of retreating subduction boundaries formed during <span class="hlt">continental</span> collision</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Retreating subduction boundaries, formed where the rate of subduction exceeds the rate of overall <span class="hlt">plate</span> convergence, appear to be commonly developed features within regions of early or incomplete continent-continent collision. They are characterized by regional extension within the <span class="hlt">overriding</span> <span class="hlt">plate</span>, and at their leading edge, by thin-skinned arcuate thrust belts that are concave toward the <span class="hlt">overriding</span> <span class="hlt">plate</span>. As is illustrated</p> <div class="credits"> <p class="dwt_author">Leigh H. Royden</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">56</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48914224"> <span id="translatedtitle">Evolution of retreating subduction boundaries formed during <span class="hlt">continental</span> collision</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Retreating subduction boundaries, formed where the rate of subduction exceeds the rate of overall <span class="hlt">plate</span> convergence, appear to be commonly developed features within regions of early or incomplete continent-continent collision. They are characterized by regional extension within the <span class="hlt">overriding</span> <span class="hlt">plate</span> and, at their leading edge, by thin-skinned arcuate thrust belts that are concave towards the <span class="hlt">overriding</span> <span class="hlt">plate</span>. As is illustrated</p> <div class="credits"> <p class="dwt_author">Leigh H. Royden</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">57</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title43-vol2/pdf/CFR-2012-title43-vol2-sec3903-53.pdf"> <span id="translatedtitle">43 CFR 3903.53 - <span class="hlt">Overriding</span> royalties.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p class="result-summary">...to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) OIL SHALE MANAGEMENT-GENERAL Fees, Rentals, and Royalties § 3903.53 <span class="hlt">Overriding</span> royalties. The lessee must file...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2012-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">58</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUSM.U51B..06A"> <span id="translatedtitle">What do Great Subduction Earthquakes tell us About <span class="hlt">Continental</span> Deformation of the Upper <span class="hlt">Plate</span> in the Central Andes Forearc? Insights From Seismotectonics, <span class="hlt">Continental</span> Deformation and Coulomb Modelisation Along Southern Peru Margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Subduction of the Nazca <span class="hlt">plate</span> beneath the Peruvian margin has produced numerous megathrust earthquakes during the last century and still constitutes mature seismic gaps in some places such as in between Ilo (Peru) and Arica (Chile). The rupture zones of the 1604, 1784 and 1868 southern Peru events were partially reactivated by the Arequipa 2001 (Mw = 8.5) seismic event, whose rupture zone was about 350km-long and stopped its propagation towards the south on Ilo Peninsula. Just after the occurrence of 2001 event, some reactivation of <span class="hlt">continental</span> fault systems are identified and monitored thanks to the Peruvian seismic network and describe <span class="hlt">continental</span> deformation processes occurring perpendicularly to the trench or parallel to the trench, traducing the <span class="hlt">continental</span> <span class="hlt">plate</span> response to major subduction earthquakes and some partitioning of the deformation. The Chololo and associated ( perpendicular to the trench) fault systems define some 80-km-long margin crustal blocks and the major one coincides with the 2001 earthquake southern limit of the rupture zone as it propagated to the south. These blocks are made from Late Jurassic and Cretaceous plutonic rocks from the Coastal Batholith; these are outcropping in some places and are evidenced by the aeromagnetic mapping elsewhere around the area. Northward along the subduction zone, another boundary between two rupture zones of major subduction earthquake was reactivated recently, perpendicularly to the trench, by the seismic crisis of October 2006, M=6.4, near Lima, right at the southern end of the rupture zone of the 1974 event (Mw=8.1).Those boundaries corresponding to discontinuities (lithospheric fault systems) in the upper <span class="hlt">plate</span>, trending nearly perpendicular to the trench, act as earthquake barriers during rupture of large seismic events. Additionally occurred on 20 of November 2006 another seismic event (Mw=5.6 Neic, Ml=5.3) in Tacna region, showing a reverse focal mechanism compatible with the trend of the Sama Calientes Fault system (parallel to the trench) and a crustal depth of about 20km. Such a magnitud and crustal depth in the area correlates perfectly with the Quaternary geomorphic evidences of tectonic activity along the Sama-Calientes thrust fault in the forearc in Southern Peru. Some questions are raised by the occurrence of such <span class="hlt">continental</span> seismicity, just after a major subduction event, as none has been registered in the area since more than 40 years. <span class="hlt">Continental</span> fault systems constitute a key to the understanding of the forearc deformation in the Arica Elbow, where the Andes obliquity with respect to the Nazca <span class="hlt">plate</span> convergence direction. Also these results suggest that <span class="hlt">continental</span> deformation should give us clues to define the pattern of segmentation of the subduction zone by studying seismotectonics and its relation to the segmentation of the upper <span class="hlt">continental</span> <span class="hlt">plate</span>.</p> <div class="credits"> <p class="dwt_author">Audin, L.; Perfettini, H.; Tavera, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">59</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ia.usu.edu/viewproject.php?project=ia:15719"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Students will go over the main points of <span class="hlt">plate</span> tectonics, including the theory of <span class="hlt">continental</span> drift, different types of <span class="hlt">plate</span> boundaries, seafloor spreading, and convection currents. We have been spending time learning about <span class="hlt">plate</span> tectonics. We have discussed the theory of <span class="hlt">continental</span> drift, we have talked about the different types of <span class="hlt">plate</span> boundaries, we have also learned about seafloor spreading and convection currents. <span class="hlt">Plate</span> Boundary Diagram Now is your chance ...</p> <div class="credits"> <p class="dwt_author">Rohlfing, Mrs.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-02-03</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">60</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013E%26PSL.380...98L"> <span id="translatedtitle">Collision of <span class="hlt">continental</span> corner from 3-D numerical modeling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary"><span class="hlt">Continental</span> collision has been extensively investigated with 2-D numerical models assuming infinitely wide <span class="hlt">plates</span> or insignificant along-strike deformation in the third dimension. However, the corners of natural collision zones normally have structural characteristics that differ from linear parts of mountain belt. We conducted 3-D high-resolution numerical simulations to study the dynamics of a <span class="hlt">continental</span> corner (lateral <span class="hlt">continental</span>/oceanic transition zone) during subduction/collision. The results demonstrate different modes between the oceanic subduction side (continuous subduction and retreating trench) and the <span class="hlt">continental</span> collision side (slab break-off and topography uplift). Slab break-off occurs at a depth (?100 km to ˜300 km) that depends on the convergence velocity. The numerical models produce lateral extrusion of the <span class="hlt">overriding</span> crust from the collisional side to the subduction side, which is also a phenomenon recognized around natural collision of <span class="hlt">continental</span> corners, for instance around the western corner of the Arabia–Asia collision zone and around the eastern corner of the India–Asia collision zone. Modeling results also indicate that extrusion tectonics may be driven both from above by the topography and gravitational potentials and from below by the trench retreat and asthenospheric mantle return flow, which supports the link between deep mantle dynamics and shallower crustal deformation.</p> <div class="credits"> <p class="dwt_author">Li, Zhong-Hai; Xu, Zhiqin; Gerya, Taras; Burg, Jean-Pierre</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-10-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_2");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a style="font-weight: bold;">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_4");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_3 div --> <div id="page_4" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_3");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a style="font-weight: bold;">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_5");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">61</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..12.6612S"> <span id="translatedtitle">Evolution of <span class="hlt">continental</span> collision styles since the Precambrian</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The relevance of modern tectonics to ancient orogens is a matter of international debate. Ultrahigh-pressure (UHP) methamorphic rocks of <span class="hlt">continental</span> origin provide evidence for subduction of the <span class="hlt">continental</span> lithosphere to mantle depths over 100 km. While UHP eclogitic rocks and high-pressure (HP) blueschists mainly occure in Phanerozoic oregenic belts, they rarely found in Precambrian terranes. To investigate a possible change of collisional style back in time which could lead to disappearing of UHP complexes from the geological surface records we performed 2D petrological-thermomechanical numerical model (I2VIS code (Gerya and Yuen, 2003)) of oceanic-<span class="hlt">continental</span> subduction followed by continent-continent collision. The reference model was chosen in such a way that it can produce UHP complexes during transition from oceanic-<span class="hlt">continental</span> subduction to continent-<span class="hlt">continental</span> collision and deliver them to the surface. Based on this model we performed series of experiments varying upper-mantle temperature (up to 250 degrees higher then present), lithosphere thickness for <span class="hlt">continental</span> <span class="hlt">plates</span> (100,140 and 180 km) and density of subcontinental lithospheric mantle (difference with underlying mantle 20 kg/m3 corresponds to present day; 50 kg/m3 corresponds to Proterosoic). The reference model shows <span class="hlt">continental</span> <span class="hlt">plate</span> subducting up to 250 km depth whereupon slab break-off occurs and <span class="hlt">continental</span> <span class="hlt">plate</span> starts to relax. During the relaxation stage <span class="hlt">continental</span> crust starts to melt and partially detach from the slab. There are two ways of moving this material from high depths upwards: 1) going upwards vertically as a buoyant plume and crossing both the mantle wedge and the <span class="hlt">overriding</span> mantle lithosphere (thanks to weakening of the lithospheric rocks by melt propagation); 2) going back along the <span class="hlt">plate</span> as a buoyant wave and penetrating into subduction channel. Both ways can lead to HP-UHP rocks formation in the end. Increasing the upper-mantle temperature we determined sharp transition from modern style of collision with formation of HP-UHP rocks to a different tectonic regime at upper mantle temperature rising by around 100 - 200 degrees (depending on the lithosphere thickness) above the present value. From this point <span class="hlt">continental</span> <span class="hlt">plate</span> subducts and induces the rising of melt-bearing hot mantle in the mantle wedge. The area of the melt-bearing mantle is not big (up to 150 km width) and after some time at the compressional conditions it starts to contract and melt starts to crystallize back. Further increase in the mantle temperature (by around 200-250 degrees above present) causes transition to another regime with the vast amount of melt-bearing mantle areas which give rise to <span class="hlt">plates</span> sinking into the mantle without any contact with the surface anymore. Based on our experiments there is no big influence on the collision style of density contrast between subcontinental lithospheric and underlying mantles, on the other hand collisional evolution strongly depends on the upper-mantle temperature and lithosphere thickness. The fact that slab breakoff and relaxation of the <span class="hlt">continental</span> <span class="hlt">plate</span> leads to melting and detachment of the <span class="hlt">continental</span> crust from the <span class="hlt">continental</span> <span class="hlt">plate</span> is interesting, and may be the mechanism by which the UHP history is erased from gneiss complexes whereas UHP history tends to be preserved in mafic and ultramafic boudins within these complexes (and sometimes within zircons within the gneisses). The transition from the modern style of collision to the determined regime with melt-bearing mantle in the mantle wedge may correspond to disappearing of UHP after 600 Ma in the <span class="hlt">continental</span> geological record.</p> <div class="credits"> <p class="dwt_author">Sizova, Elena; Gerya, Taras; Brown, Michael</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">62</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T13A2179B"> <span id="translatedtitle">Collapse of the northern Jalisco <span class="hlt">continental</span> slope:Subduction erosion, forearc slivering, or subduction beneath the Tres Marias escarpment?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Jalisco subduction zone exhibits several interesting characteristics. Among these is that convergence between the Rivera and North American <span class="hlt">plate</span> is highly oblique, especially north of 20N, the obliquity progressively increasing to the NW. By analogy to other better studied subduction zones, this distribution of forces should produce a NW-SE extension in the <span class="hlt">overriding</span> <span class="hlt">plate</span>, especially north of 20N. This has led to the proposal that the trench perpendicular Bahia de Banderas is an expression of this extension [Kostoglodov and Bandy, JGR, vol. 100, 1995]. To further investigate this proposal, multibeam bathymetric data and seafloor backscatter images, seismic reflection sub-bottom profiles and marine magnetic data were collected during the MORTIC08 campaign of the B.O. EL PUMA in March 2009. The bathymetric data provides for 100% coverage (20 to 200 meter spacing of the actual measured depth value depending on the water depth) of the <span class="hlt">continental</span> slope and trench areas north of 20N. These data indicate that a marked change occurs in the morphology of the <span class="hlt">continental</span> slope at 20N. To the north the slope consists of a broad, fairly flat plain lying between a steep lower inner trench slope to the west and a steep, concave seaward, escarpment to the east. In contrast, to the south the <span class="hlt">continental</span> slope exhibits a more gradual deepening until the steep lower inner trench slope. A prominent submarine canyon deeply incises the <span class="hlt">continental</span> slope between these two morphotectonic domains. This canyon appears to represent the boundary between two NW-SE diverging forearc blocks or slivers, consistent with the presence of oblique convergence. In contrast, the broad, fairly flat plain is better explained by subsidence induced by subduction erosion (i.e. erosion of the base of the <span class="hlt">overriding</span> <span class="hlt">plate</span> underneath the <span class="hlt">continental</span> slope area). The shoaling of the trench axis northward towards the Puerto Vallarta Graben and subsequent deepening may be related to subduction of the Rivera <span class="hlt">Plate</span> beneath the Tres Marias Escarpment.</p> <div class="credits"> <p class="dwt_author">Bandy, W. L.; Mortera-Gutierrez, C. A.; Ortiz-Zamora, G.; Ortega-Ramirez, J.; Galindo Dominguez, R. E.; Ponce-Núñez, F.; Pérez-Calderón, D.; Rufino-Contreras, I.; Valle-Hernández, S.; Pérez-González, E.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">63</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T43B2179V"> <span id="translatedtitle">Cretaceous to Paleogene speed-up and slow-down of India-Asia relative <span class="hlt">plate</span> convergence: the roles of mantle plumes and <span class="hlt">continental</span> collision</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Most authors prefer an age of collision around 50 Ma between the Tethyan Himalayas -northernmost <span class="hlt">continental</span> remnants of the Indian <span class="hlt">plate</span> - and Asia. A popular argument to support this age is a dramatic slow-down of the India-Asia convergence rate from ~18 to ~5 cm/yr between 50 and 35 Ma, interpreted to result from subduction of <span class="hlt">continental</span> lithosphere at the collision zone. However, an equally dramatic increase of the India-Asia convergence rate occurred between 65 and 50 Ma, from ~8 to 18 cm/yr. The causes of this increase are not well understood, but may reflect the dynamic influence of sublithospheric mantle flow on the India motion. Arrival of hot mantle plumes (e.g. the Deccan plume at ~65 Ma) may both increase the potential gravitational energy of a <span class="hlt">plate</span> and impose lateral mantle flow accelerating the <span class="hlt">plate</span>, especially when it contains a thick <span class="hlt">continental</span> lithospheric root. If the processes responsible for the acceleration ceases to exist, this may generate a slow-down even without a collision. Here we provide estimates of the India-Asia convergence using the India-Eurasia <span class="hlt">plate</span> circuit. The analysis of reconstruction errors shows that the speed-up and slow-down are robust, with minor variations in peak convergence velocities depending on the choice of North America-Eurasia rotations. We use two numerical codes to assess the kinematic effects of the arrival of a mantle plume at 65 Ma below India on the convergence rates. The numerical models suggest that the arrival of the plume may indeed lead to a 3-4 cm/yr increase in the convergence rate followed by a gradual slow-down with decreasing plume activity, if no changes in the lithosphere-asthenosphere coupling are assumed. However, the plume arrival is likely to weaken the asthenosphere-lithosphere coupling, leading to a more effective slab-pull effect, which may potentially generate larger a driving force, comparable with the observed 65-50 Ma acceleration. In contrast, the sudden slow-down starting at 50 Ma can not be attributed to a decrease in plume forcing, and is best explained by an increase of resisting forces generated by the arrival of <span class="hlt">continental</span> lithosphere in the subduction zone.</p> <div class="credits"> <p class="dwt_author">van Hinsbergen, D. J.; Steinberger, B. M.; Doubrovine, P. V.; Gassmöller, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">64</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.2596B"> <span id="translatedtitle">A review of Wilson Cycle <span class="hlt">plate</span> margins: What is the role of mantle plumes in <span class="hlt">continental</span> break-up along former sutures?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">It was Tuzo Wilson (1966) who recognised that the different faunal distributions on both sides of the present-day North Atlantic Ocean required the existence of an earlier proto-Atlantic Ocean. The observation that the present-day Atlantic Ocean mainly opened along a former suture was a crucial step in the formulation of the Wilson Cycle theory. The theory implies that collision zones are structures that are able to localize extensional deformation for long times after the collision has waned. We review margin pairs around the Atlantic and Indian Oceans with the aim to evaluate the extent to which oceanic opening used former sutures and to analyse the role of mantle plumes in <span class="hlt">continental</span> break-up. We aid our analyses with <span class="hlt">plate</span> tectonic reconstructions using GPlates (www.gplates.org). Already Wilson recognized that Atlantic break-up did not always follow the precise line of previous junction. For example, Atlantic opening did not utilize the Iapetus suture in Great Britain and rather than opening along the younger Rheic suture north of Florida, break-up occurred along the older Pan-African structures south of Florida. As others before us, we find no correlation of suture and break-up age. Often <span class="hlt">continental</span> break-up occurs some hundreds of Myrs after collision, but it may also take more than a Gyr, as for example for Australia-Antarctica and Congo-São Francisco. This places serious constraints on potential collision zone weakening mechanisms. Several studies have pointed to a link between <span class="hlt">continental</span> break-up and large-scale mantle upwellings. It is, however, much debated whether plumes use existing rifts as a pathway, or whether plumes play an active role in causing rifting. It is also important to realise that in several cases break-up cannot be related to plume activity. Examples are the Iberia-Newfoundland, Equatorial Atlantic Ocean, and Australia-Antarctica <span class="hlt">plate</span> margins. For margins that are associated with large igneous provinces (LIPs), we find a positive correlation between break-up age and LIP age. We interpret this to indicate that plumes can aid the factual <span class="hlt">continental</span> break-up. However, plumes may have been guided towards the rift for margins that experienced a long rift history (e.g., Norway-Greenland), to then trigger the break-up. This could offer a partial reconciliation in the debate of a passive or active role for mantle plumes in <span class="hlt">continental</span> break-up. (Wilson, J.T., 1966. Did the Atlantic close and then re-open? Nature 211, 676-681)</p> <div class="credits"> <p class="dwt_author">Buiter, Susanne; Torsvik, Trond</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">65</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T51A2308T"> <span id="translatedtitle">Numerical modeling of subduction, accretion, and collision of island arc crust onto <span class="hlt">continental</span> crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Arc-continent collision occurs when a subducting continent collides into the island arc on the <span class="hlt">overriding</span> <span class="hlt">plate</span> or when the island arc is on the subducting <span class="hlt">plate</span> with an <span class="hlt">overriding</span> continent. In addition to arc-continent collision, the latter case can lead to full subduction of the arc or accretion parts of arc crust. Accreted terranes composed of arc crustal material are present in the geological record as imbricated slices of crustal rocks or crustal blocks intermingled with accretionary prism rocks. We use numerical experiments to test the importance of different mechanical parameters of the arc crust that allow the arc to subduct, accrete, or collide with an <span class="hlt">overriding</span> continent. Our experiments specifically focus on the effects of lithospheric buoyancy and detachment layers in the arc crust on subduction geodynamics. We examine the geodynamics of island arc-continent interaction using thermo-mechanical experiments that incorporate a free surface and viscous-plastic rheology. In our numerical experiments, subduction is allowed to freely evolve by including a low viscosity subduction channel. We vary buoyancy and detachment layers for an island arc located on the subducting oceanic <span class="hlt">plate</span> with an <span class="hlt">overriding</span> <span class="hlt">continental</span> <span class="hlt">plate</span>. The rheological structure of the island arc is represented with upper, middle, and lower crust layers illustrative of the seismic crustal structure of modern arcs. Lithospheric buoyancy is varied by changing the island arc crustal thickness and density. We impose various detachment layers in the arc crust to examine the effect on subduction, accretion, or collision. A basal detachment layer represents the ultramafic crust-mantle transition layer that is posited to founder due to high densities or serve as a weak delamination layer during collision. Detachment layers at other depths represent layers weakened by backarc rifting. Our numerical experiments show that the influence of detachment layers outweighs buoyancy when testing the ability of an island arc to accrete. The depth of the primary detachment layer controls the thickness of arc crust that is underplated to the <span class="hlt">overriding</span> continent. Numerical experiments without detachment layers show that the island arc lithospheric buoyancy will lead to docking and collision if the downward force of the subducting slab pull is less than the ridge push.</p> <div class="credits"> <p class="dwt_author">Tetreault, J. L.; Buiter, S.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">66</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://learningcenter.nsta.org/product_detail.aspx?id=10.2505/7/SCB-PT.2.1"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This Science Object is the second of five Science Objects in the <span class="hlt">Plate</span> Tectonics SciPack. It provides a conceptual understanding of what <span class="hlt">plates</span> are and how they move, contributing to a constantly changing surface. The Earth's continents and ocean basins are made up of <span class="hlt">plates</span> consisting of the crust and the upper part of the mantle. One <span class="hlt">plate</span> can consist of both <span class="hlt">continental</span> and oceanic crust. These <span class="hlt">plates</span> move very slowly (an inch or so per year) on the hot, deformable layer of the mantle beneath them. The outward transfer of Earth's internal heat drives convection circulation in the mantle. This convection, together with gravitational pull on the <span class="hlt">plates</span> themselves, causes the <span class="hlt">plates</span> to move. Learning Outcomes:� Identify that the outermost layer of Earth is made up of separate <span class="hlt">plates</span>.� Choose the correct speed of the motion of <span class="hlt">plates</span>.� Identify the ocean floor as <span class="hlt">plate</span>, in addition to the continents (to combat the common idea that only continents are <span class="hlt">plates</span>, floating around on the oceans).� Recognize that oceans and continents can coexist on the same <span class="hlt">plate</span>.</p> <div class="credits"> <p class="dwt_author">National Science Teachers Association (NSTA)</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">67</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013GGG....14.2310N"> <span id="translatedtitle">Dynamics of outer-rise faulting in oceanic-<span class="hlt">continental</span> subduction systems</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">During subduction, bending of downgoing oceanic lithosphere gives rise to normal faulting due to the extensional stress state generated in the upper <span class="hlt">plate</span>. As deformation patterns inherently reflect a material's state of stress and rheology, extensive global observations of outer-rise faulting patterns and subduction dynamics provide a unique opportunity to examine the factors controlling outer-rise deformation. Despite a wide range of observed oceanic <span class="hlt">plate</span> ages, convergence rates and slab pull magnitudes across modern subduction systems, however, measured outer-rise faulting patterns show effectively no correlation to variations in these parameters. This lack of correlation may reflect that outer-rise faulting patterns are strongly sensitive to all of these parameters, are dependent on additional parameters such as downgoing-<span class="hlt">overriding</span> <span class="hlt">plate</span> coupling or that existing faulting measurements require additional analysis. In order to provide a basis for future analysis of outer-rise faulting patterns, we build on previous thermo-mechanical numerical models of outer-rise deformation and explore the relationship between outer-rise faulting patterns, subduction dynamics and brittle rheology in an oceanic-<span class="hlt">continental</span> subduction system. Analysis of time-averaged outer-rise faulting patterns indicates that downgoing <span class="hlt">plate</span> age and velocity, downgoing-<span class="hlt">overriding</span> <span class="hlt">plate</span> coupling and slab pull all significantly affect faulting patterns, while variations in brittle rheology have a significantly smaller impact. These relationships reflect that the sensitivity of outer-rise faulting patterns to the frictional properties of the oceanic crust and mantle is small compared to variations in the overall stress state and deformation rate of subduction systems. In order to gain additional insight into the origin outer-rise faulting patterns, future numerical studies should focus on specific regions in order to place constraints on the structure of the downgoing <span class="hlt">plate</span> and dynamics of the subduction system.</p> <div class="credits"> <p class="dwt_author">Naliboff, John B.; Billen, Magali I.; Gerya, Taras; Saunders, Jessie</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-07-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">68</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004GeoJI.159..749K"> <span id="translatedtitle">Crustal structure of the Peruvian <span class="hlt">continental</span> margin from wide-angle seismic studies</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Active seismic investigations along the Pacific margin off Peru were carried out using ocean bottom hydrophones and seismometers. The structure and the P-wave velocities of the obliquely subducting oceanic Nazca <span class="hlt">Plate</span> and <span class="hlt">overriding</span> South American <span class="hlt">Plate</span> from 8°S to 15°S were determined by modelling the wide-angle seismic data combined with the analysis of reflection seismic data. Three detailed cross-sections of the subduction zone of the Peruvian margin and one strike-line across the Lima Basin are presented here. The oceanic crust of the Nazca <span class="hlt">Plate</span>, with a thin pelagic sediment cover, ranging from 0-200 m, has an average thickness of 6.4 km. At 8°S it thins to 4 km in the area of Trujillo Trough, a graben-like structure. Across the margin, the <span class="hlt">plate</span> boundary can be traced to 25 km depth. As inferred from the velocity models, a frontal prism exists adjacent to the trench axis and is associated with the steep lower slope. Terrigeneous sediments are proposed to be transported downslope due to gravitational forces and comprise the frontal prism, characterized by low seismic P-wave velocities. The lower slope material accretes against a backstop structure, which is defined by higher seismic P-wave velocities, 3.5-6.0 km s-1. The large variations in surface slope along one transect may reflect basal removal of upper <span class="hlt">plate</span> material, thus steepening the slope surface. Subduction processes along the Peruvian margin are dominated by tectonic erosion indicated by the large margin taper, the shape and bending of the subducting slab, laterally varying slope angles and the material properties of the <span class="hlt">overriding</span> <span class="hlt">continental</span> <span class="hlt">plate</span>. The erosional mechanisms, frontal and basal erosion, result in the steepening of the slope and consequent slope failure.</p> <div class="credits"> <p class="dwt_author">Krabbenhöft, A.; Bialas, J.; Kopp, H.; Kukowski, N.; Hübscher, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">69</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013E%26PSL.364...44T"> <span id="translatedtitle">Extension of <span class="hlt">continental</span> crust by anelastic deformation during the 2011 Tohoku-oki earthquake: The role of extensional faulting in the generation of a great tsunami</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Observations of seafloor morphologies and environments made before and after the 2011 Tohoku-oki earthquake reveal open fissures, generated during the earthquake, where the fault trace is interpreted on seismic profiles to intersect the seafloor. Anomalously high heat flow was observed at a landward-dipping normal fault in August 2011, five months after the earthquake, but by August 2012 heat flow measured at the same station had decreased to close to the background value, which suggests that the normal fault ruptured during the 2011 earthquake. These seafloor observations and measurements demonstrate deformation that was both extensional and anelastic within the <span class="hlt">overriding</span> <span class="hlt">continental</span> <span class="hlt">plate</span> during the 2011 earthquake. Seismic profiles as well as seafloor bathymetry data in the tsunami source area further demonstrate that landward-dipping normal faults (extensional faults) collapse the <span class="hlt">continental</span> framework and detach the seaward frontal crust from the landward crust at far landward from the trench. The extensional and anelastic deformation (i.e., normal faulting) observed in both seafloor observations and seismic profiles allows the smooth seaward movement of the <span class="hlt">continental</span> crust. Seaward extension of the <span class="hlt">continental</span> crust close to the trench axis in response to normal faulting is a characteristic structure of tsunami source areas, as similar landward-dipping normal faults have been observed at other convergent <span class="hlt">plate</span> margins where tsunamigenic earthquakes have occurred. We propose that the existence of a normal fault that moves the <span class="hlt">continental</span> crust close to the trench can be considered one indicator of a source area for a huge tsunami.</p> <div class="credits"> <p class="dwt_author">Tsuji, Takeshi; Kawamura, Kiichiro; Kanamatsu, Toshiya; Kasaya, Takafumi; Fujikura, Katsunori; Ito, Yoshihiro; Tsuru, Tetsuro; Kinoshita, Masataka</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">70</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/44256735"> <span id="translatedtitle"><span class="hlt">Plate</span> detachment, asthenosphere upwelling, and topography across subduction zones</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This study analyzes the topography across subduction zones, considering the separate contributions of the crust and the mantle lithosphere to the observed surface elevation. We have found a transition from a region where the <span class="hlt">overriding</span> <span class="hlt">plate</span> is coupled to the descending slab and pulled down along with it to a region where the <span class="hlt">overriding</span> <span class="hlt">plate</span> floats freely on the asthenosphere.</p> <div class="credits"> <p class="dwt_author">Zohar Gvirtzman; Amos Nur</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">71</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6256055"> <span id="translatedtitle">Unique Signal <span class="hlt">Override</span> Plug electromagnetic test report</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The MC4039 Unique Signal <span class="hlt">Override</span> Plug (USOP) provides the unique signal for the B90 when fielded on aircraft that are not equipped with unique signal capability. Since the USOP is field installed, the concern is that it might be susceptible to electromagnetic radiation prior to installation on the weapon. This report documents a characterization of the USOP, evaluates various techniques for attaching electromagnetic shields, and evaluates the susceptibility of a fully assembled passive-USOP. Tests conducted evaluated the electromagnetic susceptibility of the passive, unconnected USOP. During normal operation the USOP is powered directly from the weapon. During the course of this test program two prototypes were developed. The prototype 1 USOP internal circuitry contains one SA3727 chip, five diodes, three resistors, and two capacitors; these are mounted on a circular circuit board and contained inside a metal back shell cover, which serves as an electromagnetic shield. The prototype 2 design incorporated four changes. The manufacturer of the SA3727 chip was changed from Lasarray to LSI Logic, the circuit board ground was tied to the case ground through a straight wire, Cl was changed from 1 microfarad to 0.1 microfarads. and the circuit board was changed, as required. 2 refs., 17 figs., 3 tabs. (JF)</p> <div class="credits"> <p class="dwt_author">Bonn, R.H.</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">72</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=PB81204471"> <span id="translatedtitle">Thin-Skinned <span class="hlt">Plate</span>-Tectonic Model for Collision-Type Orogenesis.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">The <span class="hlt">plate</span>-tectonic theory postulates the presence of three elements in a mountain-belt: (1) <span class="hlt">overriding</span> <span class="hlt">plate</span>, (2) suture, and (3) underthrusting <span class="hlt">plate</span>. A thin-skinned model for collision type of mountain ranges suggests that both the <span class="hlt">overriding</span> and undert...</p> <div class="credits"> <p class="dwt_author">K. J. Hsue</p> <p class="dwt_publisher"></p> <p class="publishDate">1980-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">73</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title43-vol2/pdf/CFR-2012-title43-vol2-sec3933-32.pdf"> <span id="translatedtitle">43 CFR 3933.32 - <span class="hlt">Overriding</span> royalty interests.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p class="result-summary">...Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE EXPLORATION AND LEASES Assignments and Subleases § 3933.32 <span class="hlt">Overriding</span> royalty interests. File at the...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2012-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">74</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2013-title5-vol3/pdf/CFR-2013-title5-vol3-sec1320-15.pdf"> <span id="translatedtitle">5 CFR 1320.15 - Independent regulatory agency <span class="hlt">override</span> authority.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p class="result-summary">...BURDENS ON THE PUBLIC § 1320.15 Independent regulatory agency <span class="hlt">override</span> authority. (a) An independent regulatory agency which is administered by two...of a commission, board, or similar body, may by majority vote void:...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2013-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">75</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.enchantedlearning.com/subjects/astronomy/activities/findit/qtectonics.shtml"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics Quiz</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This quiz for younger students asks them 10 questions about <span class="hlt">plate</span> motions, rock types in <span class="hlt">continental</span> and oceanic crust, crustal formation and mountain building, the supercontinent Pangea, and the theory of <span class="hlt">continental</span> drift. A link to a page on <span class="hlt">continental</span> drift provides information to answer the questions.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">76</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUSM.T23A..06B"> <span id="translatedtitle">Uplift of <span class="hlt">continental</span> crustal blocks adjacent to the Rancheria Basin-Guasare area: the effects of Maastrichtian-Paleocene collision along the southern Caribbean <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">In the Rancheria basin (RB) and Guasare area (GA), Maastrichtian-Paleocene synorogenic strata overlie the Aptian-Campanian carbonate platform. Nowadays, RB is bounded to the west by metamorphic-and-igneous cored Santa Marta massif, where Upper Cretaceous strata overlie unconformably pre-Cretaceous rocks. The eastern boundary of the RB is the Perija range that includes volcaniclastic and sedimentary rocks of Jurassic and Cretaceous age in the hanging-wall of a NW-verging, low-angle dipping thrust belt. The GA is on the eastern foothills of the Perija range and corresponds to the western boundary of the Maracaibo basin. Strata architecture, seismic reflectors, gravity, provenance, and paleocurrent analyses carried out in those basins constrain the timing and style of uplift of Santa Marta massif and Perija range, which are linked with tectonism along the southern Caribbean <span class="hlt">plate</span>. Maastrichtian-Paleocene strata thicken eastward up to 2.2 km in the RB, and this succession includes (in stratigraphic order): foram-rich calcareous mudstone, oyster-pelecypod rich carbonate-siliciclastic strata, coal- bearing mudstones and feldspar-lithic-rich fluvial sandstones. Internal disconformities and truncations of seismic reflectors are identified to the west of the RB, but there are not major thrust faults at this part of the basin to explain such unconformities and truncations. In Early Paleocene, carbonates developed better to the west of the RB, whereas mixed carbonate-siliciclastic deposition continued toward the east of the RB. In early Late Paleocene, influx of terrigenous material (key grains=metamorphic, microcline and garnet fragments) derived from the Santa Marta massif increased to the west, but to the east of the RB and GA carbonate-siliciclastic and carbonate deposition continued, respectively. In mid-Late Paleocene, diachronous eastward advance of paralic/deltaic environments, tropical humid climate, and high subsidence rates favored production and preservation of peat in RB and GA. In the late Late Paleocene, inversion along a buried graben system under the Perija range explain supply toward RB and GA of micritic, volcanic, and sedimentary rock fragments, and the record of a thinner Upper Paleocene strata in the GA than in the RB. Tectonic subsidence in the RB was mainly related to pivoting of the Santa Marta massif as result of collision of the Maracaibo <span class="hlt">continental</span> sub-<span class="hlt">plate</span> with the southern margin of the Caribbean oceanic <span class="hlt">plate</span>. This model explains the generation of accommodation space in the RB without faulting, denudation of upper crustal material of the Santa Marta massif, early capture of terrigenous detritus in the RB that favored carbonate deposition in the GA, the mechanism of initial inversion of the Perija range, and the present positive gravity anomaly under the Santa Marta massif.</p> <div class="credits"> <p class="dwt_author">Bayona, G.; Montes, C.; Jaramillo, C.; Ojeda, G.; Cardona, A.; Pardo, A.; Lamus, F.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">77</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012Tectp.532..271L"> <span id="translatedtitle">Magmatic switch-on and switch-off along the South China <span class="hlt">continental</span> margin since the Permian: Transition from an Andean-type to a Western Pacific-type <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Detrital zircon provenance data for the Tananao schist in eastern Taiwan is consistent with its protolith being deposited on the South China <span class="hlt">continental</span> margin at around, or soon after, 150 Ma, rather than being of an exotic origin and much older as previously suggested. The absence of ca. 200 Ma zircons agrees with the presence of a magmatic gap in the region after the orogenic and magmatic front migrated to central South China, due to a flat-slab subduction. The characteristic lack of input from interior South China (i.e., the lack of 1100-750 Ma and 470-420 Ma populations), and the immature nature of some of the schist units, suggest that they were sourced from the nearby coastal regions. On the other hand, they exhibit a dominant 190-150 Ma magmatic zircon population, suggesting the presence of abundant magmatic rocks of that age along the coastal regions. This, along with our newly discovered ca. 180 Ma I-type granites from eastern Zhejiang and other ca. 190-180 Ma magmatic rocks recently reported from the coastal regions, led us to propose that a new <span class="hlt">continental</span> arc was initiated after ca. 190 Ma along the coastal region after a magmatic gap due to flat-slab subduction. This newly initiated arc likely persisted until ca. 90 Ma, and is represented by the I-type granitic rocks in eastern Taiwan. Slab roll-back likely caused the arc system to retreat towards the Pacific Ocean after 90 Ma, and ca. 60-17 Ma bimodal magmatism adjacent to the South China Sea signifies <span class="hlt">continental</span> margin extension in the lead-up to, and during, the opening of the South China Sea. We thus argue that the <span class="hlt">continental</span> margin of East Asia was transformed from an Andean-type <span class="hlt">plate</span> margin at 280-90 Ma, to the present-day Western Pacific-type <span class="hlt">plate</span> margin soon after 90 Ma.</p> <div class="credits"> <p class="dwt_author">Li, Zheng-Xiang; Li, Xian-Hua; Chung, Sun-Lin; Lo, Ching-Hua; Xu, Xisheng; Li, Wu-Xian</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">78</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55243958"> <span id="translatedtitle">On the effects of <span class="hlt">continental</span> collisions on mantle flow</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Both the thermal properties and the accretionary history of the <span class="hlt">continental</span> cratons and fragments which assemble to form a supercontinent may govern the growing continent's stability. The influence of <span class="hlt">continental</span> collisions on deep mantle flow is considered here by simulating <span class="hlt">continental</span> aggregation in numerical mantle convection models incorporating distinct <span class="hlt">continental</span> and oceanic <span class="hlt">plates</span>. The results presented were obtained using a</p> <div class="credits"> <p class="dwt_author">Julian Philip Lowman</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">79</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1999Geo....27..563G"> <span id="translatedtitle"><span class="hlt">Plate</span> detachment, asthenosphere upwelling, and topography across subduction zones</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">This study analyzes the topography across subduction zones, considering the separate contributions of the crust and the mantle lithosphere to the observed surface elevation. We have found a transition from a region where the <span class="hlt">overriding</span> <span class="hlt">plate</span> is coupled to the descending slab and pulled down along with it to a region where the <span class="hlt">overriding</span> <span class="hlt">plate</span> floats freely on the asthenosphere. When the subducting slab retreats oceanward rapidly this transition is abrupt, and the edge of the <span class="hlt">overriding</span> <span class="hlt">plate</span> is uplifted. We propose that at some point during rapid slab rollback the <span class="hlt">overriding</span> <span class="hlt">plate</span> detaches and rebounds like a boat released from its keel. This event is associated with suction of asthenospheric material into the gap that is opened between the <span class="hlt">plates</span> up to the base of the crust. As a result, the forearc uplifts, and magmatism in the arc increases.</p> <div class="credits"> <p class="dwt_author">Gvirtzman, Zohar; Nur, Amos</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-06-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">80</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://learningcenter.nsta.org/product_detail.aspx?id=10.2505/6/SCP-PT.0.1"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">The <span class="hlt">Plate</span> Tectonics SciPack explores the various materials that make up Earth and the processes they undergo to provide a framework for understanding how continents are created and change over time. The focus is on Standards and Benchmarks related to Earth's layers, oceanic and <span class="hlt">continental</span> <span class="hlt">plates</span> and the interactions between <span class="hlt">plates</span>.In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components:� Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. � Access to one-on-one support via e-mail to content "Wizards".� Final Assessment which can be used to certify mastery of the concepts.Learning Outcomes:<span class="hlt">Plate</span> Tectonics: Layered Earth� Identify that Earth has layers (not necessarily name them), and that the interior is hotter and more dense than the crust.� Identify the crust as mechanically strong, and the underlying mantle as deformable and convecting.<span class="hlt">Plate</span> Tectonics: Plates� Identify that the outermost layer of Earth is made up of separate <span class="hlt">plates</span>.� Choose the correct speed of the motion of <span class="hlt">plates</span>.� Identify the ocean floor as <span class="hlt">plate</span>, in addition to the continents (to combat the common idea that only continents are <span class="hlt">plates</span>, floating around on the oceans).� Recognize that oceans and continents can coexist on the same <span class="hlt">plate.Plate</span> Tectonics: <span class="hlt">Plate</span> Interactions� Identify the different interactions between <span class="hlt">plates</span>.� Discuss what happens as a result of those interactions.<span class="hlt">Plate</span> Tectonics: Consequences of <span class="hlt">Plate</span> Interactions� Explain why volcanoes and earthquakes occur along <span class="hlt">plate</span> boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of <span class="hlt">plate</span> interactions.<span class="hlt">Plate</span> Tectonics: Lines of Evidence� Use <span class="hlt">plate</span> tectonics to explain changes in continents and their positions over geologic time.� Provide evidence for the idea of <span class="hlt">plates</span>, including the location of earthquakes and volcanoes, <span class="hlt">continental</span> drift, magnetic orientation of rocks in the ocean floor, etc.</p> <div class="credits"> <p class="dwt_author">National Science Teachers Association (NSTA)</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-03-21</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_3");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a style="font-weight: bold;">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_5");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_4 div --> <div id="page_5" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_4");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a style="font-weight: bold;">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_6");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">81</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://library.thinkquest.org/17701/high/tectonics/"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: A Continuous Process</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This page provides an introduction to <span class="hlt">plate</span> tectonics for secondary students. Topics include <span class="hlt">plate</span> motions, the layers of the Earth and oceanic versus <span class="hlt">continental</span> <span class="hlt">plates</span>. A set of links provides access to material on the processes of <span class="hlt">plate</span> tectonics occuring at <span class="hlt">plate</span> boundaries, zones of movement and instability.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">82</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUFM.G12A..02T"> <span id="translatedtitle"><span class="hlt">Continental</span> Microplate Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">During the past decade, methods of space geodesy have demonstrated that the kinematics of the intra- <span class="hlt">continental</span> deforming zones that lie between the large global <span class="hlt">plates</span> can be usefully described as relative motions among small elastic blocks or microplates. At the same time, kinematic models that assume a smoothly varying deformation field have been developed and applied to the same data. Both models generally fit the data comparably well and there is much debate about which approach--blocks or continuum--is 'better'. However, there is really no disagreement about the existence of crustal blocks in deforming zones and only their size and number are contentious. Therefore a perhaps more useful way of framing the debate is to examine the purpose of each modeling approach, its success in meeting that purpose, and its limitations. Continuum modeling approaches are typically a prelude to dynamic modeling of <span class="hlt">continental</span> deformation, thus far usually using a thin viscous sheet rheology for the lithosphere. The purpose of continuum modeling is then to quantify the forces driving and resisting motions and understand their relation to the observed deformation. This approach has been notably successful in determining the relative importance of <span class="hlt">plate</span> boundary tractions and internal buoyancy forces (gravitational potential energy) in driving intra-<span class="hlt">continental</span> deformation, particularly in central Asia and western North America. <span class="hlt">Continental</span> deformation is block-like because major faults are weak and block interiors are much stronger. The main purpose of simple rigid <span class="hlt">plate</span> kinematics is to quantify the rate and sense of slip across major faults and mountain belts, with applications to active tectonics and earthquake hazard assessment. Where available, late Quaternary and Holocene fault slip rate estimates, with few (but notable) exceptions, agree with geodetically- estimated rates obtained from the block models. Where block rotations are sufficiently large, late Cenozoic rotation rates can be determined paleomagnetically and these rates commonly agree with the space geodetic estimates. Despite several similarities, <span class="hlt">continental</span> block kinematics differs in notable ways from global <span class="hlt">plate</span> tectonics. First, microplates are much smaller, typically ~100-1000 km in size. Departures from block rigidity are small but measurable and represent either heterogeneous internal deformation or a more complex but unresolved block structure. While major oceanic <span class="hlt">plates</span> may persist for tens or 100s of Ma, <span class="hlt">continental</span> microplates change and evolve over much shorter timescales, particularly near their often geometrically irregular boundaries. The depth to which discrete block structures extend is uncertain. While some major faults probably extend through the crust into the upper mantle as narrow ductile shear zones, blocks elsewhere may be at least partially decoupled from the mantle lithosphere by pervasive ductile flow of weak lower crust. <span class="hlt">Continental</span> blocks must ultimately be subject to the same forces that drive and resist global <span class="hlt">plate</span> motions. However, the role and importance of local forces is often evident from the observed patterns of <span class="hlt">continental</span> block motion. These local forces include internal buoyancy due to lateral density gradients in <span class="hlt">continental</span> lithosphere and block boundary forces such as those caused by slab roll-back, trench suction, and resistance to subduction of buoyant lithosphere. The importance of basal tractions that may drive or resist block motions is uncertain and controversial.</p> <div class="credits"> <p class="dwt_author">Thatcher, W.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">83</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/6630395"> <span id="translatedtitle">Mechanism of Caffeine-Induced Checkpoint <span class="hlt">Override</span> in Fission Yeast</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Mitotic checkpoints restrain the onset of mitosis (M) when DNA is incompletely replicated or damaged. These checkpoints are conserved between the fission yeast Schizosaccharomyces pombe and mammals. In both types of organisms, the methylxanthine caffeine <span class="hlt">overrides</span> the synthesis (S)-M checkpoint that couples mitosis to completion of DNA S phase. The molecular target of caffeine was sought in fission yeast. Caffeine</p> <div class="credits"> <p class="dwt_author">BETTINA A. MOSER; JEAN-MARC BRONDELLO; BETH BABER-FURNARI; PAUL RUSSELL</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">84</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40028751"> <span id="translatedtitle"><span class="hlt">Continental</span> dynamics and <span class="hlt">continental</span> earthquakes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Two key research projects in geoscience field in China since the IUGG meeting in Birmingham in 1999, the project of “East\\u000a Asian <span class="hlt">Continental</span> Geodynamics” and the project of “Mechanism and Prediction of Strong <span class="hlt">Continental</span> Earthquakes” are introduced\\u000a in this paper. Some details of two projects, such as their sub-projects, some initial research results published are also\\u000a given here. Because of</p> <div class="credits"> <p class="dwt_author">Dong-Ning Zhang; Guo-Min Zhang; Pei-Zhen Zhang</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">85</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/38239632"> <span id="translatedtitle">An Empirical Investigation of the True and Fair <span class="hlt">Override</span> in the United Kingdom</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Abstract:?The True and Fair View concept requires companies to depart from GAAP or the law if necessary to present a true and fair view of the corporation's financial affairs. We analyze UK public companies invoking a true and fair <span class="hlt">override</span> to assess whether <span class="hlt">overrides</span> are associated with weakened performance, earnings quality and informativeness. We find quantified <span class="hlt">overrides</span> increase income and</p> <div class="credits"> <p class="dwt_author">Gilad Livne; Maureen McNichols</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">86</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1993GeoRL..20.2391P"> <span id="translatedtitle">Steep subduction geometry of the Rivera <span class="hlt">plate</span> beneath the Jalisco block in western Mexico</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The morphology of the Rivera <span class="hlt">plate</span> subducted beneath the Jalisco block in western Mexico is determined from accurately located hypocenters of locally recorded microearthquakes, and from earthquakes with magnitude m(sub b) is greater than or equal to 4.5 recorded at teleseismic distances. The hypocenters of these latter earthquakes are relocated, and for five of them the focal depth is constrained by the inversion of long-period body waves. The Wadati-Benioff zone inferred from these data indicates a steep subduction of the Rivera <span class="hlt">plate</span> that resembles the geometry of subduction of the Cocos <span class="hlt">plate</span> beneath Central America. It is, however, very different from the shallower and almost subhorizontal subduction of the Cocos <span class="hlt">plate</span> observed in southern Mexico, southeast of this region. The Rivera <span class="hlt">plate</span> is comparable to the Juan de Fuca <span class="hlt">plate</span> in terms of the small areal extent, young seafloor age, low relative velocity, and low teleseismic activity in the subduction zone. This study shows that the dip of both the Juan de Fuca and Rivera <span class="hlt">plates</span> are similar once they are decoupled from the <span class="hlt">overriding</span> <span class="hlt">continental</span> crust. The downgoing Rivera <span class="hlt">plate</span> initially starts with a dip of approximately 10 deg down to a depth of 20 km and then increases gradually to a constant dip of approximately 50 deg below a depth of 40 km. Intermediate-depth seismicity is low in this zone associated with the subduction of the slow (2 cm/yr) and young (9 m.y.) Rivera <span class="hlt">plate</span>. The maximum depth extent of earthquakes observed in the Rivera subduction zone is about 130 km. The andesitic, calc-alkaline Colima volcano appears to be directly related to the subduction of the Rivera <span class="hlt">plate</span>. To the NW of this volcano, the observed Quaternary volcanism in the Jalisco block, which is parallel to the trench, may also be explained by the subduction of the Rivera <span class="hlt">plate</span>.</p> <div class="credits"> <p class="dwt_author">Pardo, Mario; Suarez, Gerardo</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">87</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52928378"> <span id="translatedtitle">2Aminopurine <span class="hlt">Overrides</span> Multiple Cell Cycle Checkpoints in BHK Cells</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">BHK cells blocked at any of several points in the cell cycle <span class="hlt">override</span> their drug-induced arrest and proceed in the cycle when exposed concurrently to the protein kinase inhibitor 2-aminopurine (2-AP). For cells arrested at various points in interphase, 2-AP-induced cell cycle progression is made evident by arrival of the drug-treated cell population in mitosis. Cells that have escaped from</p> <div class="credits"> <p class="dwt_author">Paul R. Andreassen; Robert L. Margolis</p> <p class="dwt_publisher"></p> <p class="publishDate">1992-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">88</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6841176"> <span id="translatedtitle"><span class="hlt">Continental</span> shelves</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary"><span class="hlt">Continental</span> shelves form a relatively narrow fringe, of varying width, around the continents. Altogether they take up only about 7% of the ocean's surface and less than 0.2% if its volume. Nevertheless, their specific biological characteristics and economical importance justify a separate discussion in this series. Ecosystems of the World. The specific biological characteristics are due to the position of <span class="hlt">continental</span> shelves between the land masses on one side and the oceans on the other, to their relative shallowness and variable sea-floor texture and to the fact that, besides residual currents, tidal streams exert a great influence on the movements of water bodies.</p> <div class="credits"> <p class="dwt_author">Postma, H.; Zijlstra</p> <p class="dwt_publisher"></p> <p class="publishDate">1987-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">89</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42054462"> <span id="translatedtitle">Margins: A new conceptual approach to <span class="hlt">continental</span> margin research</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The geology of continents is to a large degree the geology of <span class="hlt">continental</span> margins. The margins mark the site where materials that form major components of the <span class="hlt">continental</span> crust are distilled from Earth's mantle and where continents grow through <span class="hlt">plate</span> interactions that progressively incorporate these margins into the <span class="hlt">continental</span> mass.Much of the continents consists of the remnants of ancient margins</p> <div class="credits"> <p class="dwt_author">John Mutter</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">90</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40382185"> <span id="translatedtitle">Focal mechanism of a shock at the northwestern boundary of the pacific <span class="hlt">plate</span>: Extensional feature of the oceanic lithosphere and compressional feature of the <span class="hlt">continental</span> lithosphere</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">First motions of P-wave and S-wave polarization angles for a shallow shock that occurred on July 25, 1965, at about 70 km oceanward from the Kuril trench indicate a double couple dip-slip source with a horizontal tension axis in the direction perpendicular to the trench. This suggests that the Pacific <span class="hlt">plate</span> in this region is being extended in this direction.</p> <div class="credits"> <p class="dwt_author">Kunihiko Shimazaki</p> <p class="dwt_publisher"></p> <p class="publishDate">1972-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">91</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://esminfo.prenhall.com/science/geoanimations/animations/35_VolcanicAct.html"> <span id="translatedtitle">Tectonic Settings and Volcanic Activity: <span class="hlt">Continental</span> volcanic arc & Volcanic-island-arc</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">The representation depicts the formation of volcanic mountains at <span class="hlt">plate</span> boundaries when an oceanic <span class="hlt">plate</span> sinks under a <span class="hlt">continental</span> <span class="hlt">plate</span>, and when two oceanic <span class="hlt">plates</span> collide and one sinks under the other. This representation is found under the "<span class="hlt">Continental</span> volcanic arc" and "Volcanic island arc" tabs.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">92</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011GeCoA..75.2664J"> <span id="translatedtitle">Crustal contamination and mantle source characteristics in <span class="hlt">continental</span> intra-<span class="hlt">plate</span> volcanic rocks: Pb, Hf and Os isotopes from central European volcanic province basalts</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We report new Os-Pb-Hf isotope data for a suite of alkaline to basaltic (nephelinites, basanites, olivine tholeiites to quartz-tholeiites) lavas from the Miocene Vogelsberg (Germany), the largest of the rift-related <span class="hlt">continental</span> volcanic complexes of the Central European Volcanic Province (CEVP). 187Os/ 188Os in primitive (high-MgO) alkaline lavas show a much wider range than has been observed in alkaline basalts and peridotite xenoliths from elsewhere in the CEVP, from ratios similar to those in modern MORB and OIB (0.1260-0.1451; 58.9-168 ppt Os) to more radiogenic ratios (0.1908 and 0.2197; 27.6-15.1 ppt Os). Radiogenic Os is associated with high ? Hf and ? Nd, low 87Sr/ 86Sr and does not correlate with Mg ? or incompatible trace elements (e.g. Ce/Pb), suggesting the presence of a radiogenic endmember in the mantle rather than crustal contamination as the source of radiogenic Os. This contrasts with another high-Mg alkaline lava characterized by highly radiogenic 187Os/ 188Os (0.4344, 10.3 ppt Os), lower ? Hf and ? Nd, higher 87Sr/ 86Sr, and Pb isotope signatures than the other alkaline lavas with similar trace element composition suggestive of contamination with crustal material. Hafnium (? Hf: +8.9 to +5.0) and Pb isotope compositions ( 206Pb/ 204Pb: 19.10-19.61; 207Pb/ 204Pb: 15.56-15.60) of the alkaline rocks fall within the range of enriched MORB and some OIB. The Vogelsberg tholeiites show even more diverse 187Os/ 188Os, ranging from 0.1487 in Os-rich olivine tholeiite (31.7 ppt) to ratios as high as 0.7526 in other olivine-tholeiites and in quartz-tholeiites with lower Os concentrations (10.3-2.0 ppt). Low- 187Os/ 188Os tholeiites show Pb-Hf isotope ratios ( 206Pb/ 204Pb:18.81; 207Pb/ 204Pb: 15.61; ? Hf: +2.7) that are distinct from those in alkaline lavas with similar 187Os/ 188Os and originate from a different mantle source. By contrast, the combination of radiogenic Os and low 206Pb/ 204Pb and ? Hf in the other tholeiites probably reflects crustal contamination. The association at Vogelsberg of primitive alkaline and tholeiitic lavas with a range of MORB- to OIB-like Os-Pb-Hf-Nd-Sr isotopic characteristics requires at least two asthenospheric magma sources. This is consistent with trace element modelling which suggests that the alkaline and tholeiitic parent magmas represent mixtures of melts from garnet and spinel peridotite sources (both with amphibole), implying an origin of the magmas in the garnet peridotite-spinel peridotite transition zone, probably at the asthenosphere-lithosphere interface. We propose that uncontaminated Vogelsberg lavas originated in 'metasomatized' mantle, involving a 3-stage model: (1) early carbonatite metasomatism several 10-100 Ma before the melting event (2) deposition of low-degree asthenospheric melts from carbonated peridotite at the lithosphere-asthenosphere thermal boundary produces hydrous amphibole-bearing veins or patches, and (3) remobilization of this modified lithospheric mantle into other asthenospheric melts passing through the same area later. In keeping with 'metasomatized' mantle models for other <span class="hlt">continental</span> basalt provinces, we envisage that stage (2) is short-lived (few Ma), thus producing a prominent lithospheric trace element signature without changing the asthenospheric isotopic signatures. Models of this type can explain the peculiar mix of lithospheric (prominent depletions of Rb and K) and asthenospheric (OIB-like high 187Os/ 188Os, 143Nd/ 144Nd and 176Hf/ 177Hf) signatures observed in the Vogelsberg and many other <span class="hlt">continental</span> basalt suites.</p> <div class="credits"> <p class="dwt_author">Jung, S.; Pfänder, J. A.; Brauns, M.; Maas, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">93</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55115216"> <span id="translatedtitle">Some Key Issues in Contemporary <span class="hlt">Continental</span> Tectonics: An Overview</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Plate</span> tectonics theory, grounded on the assumption of nearly rigidity of <span class="hlt">plate</span> interior, is elucidated as deformation concentrated on the narrowly defined <span class="hlt">plate</span> boundaries; however, the current flooding datum of space-based geodetic observations have shown that <span class="hlt">continental</span> deformation is not confined to the nominated <span class="hlt">plate</span> boundaries, but even expanding to the inland area thousand kilometers far away from which. To</p> <div class="credits"> <p class="dwt_author">S. Liu; L. Wang; C. Li</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">94</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.teachersdomain.org/6-8/sci/ess/earthsys/shake/index.html"> <span id="translatedtitle">Mountain Maker- Earth Shaker (Convergent Boundary: oceanic-<span class="hlt">continental</span>)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">The representation depicts <span class="hlt">plate</span> boundary interactions. The convergent boundary is one part of a larger interactive diagram (the 2nd slider/ arrow from the left), that focuses on an ocean <span class="hlt">plate</span> pressing against a <span class="hlt">continental</span> <span class="hlt">plate</span>. This review specifically addresses the part of the resource dealing with what happens when <span class="hlt">plates</span> pull apart. The "show intro" link provides instruction for diagram manipulation.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">95</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17744717"> <span id="translatedtitle">Mantle plumes and <span class="hlt">continental</span> tectonics.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Mantle plumes and <span class="hlt">plate</span> tectonics, the result of two distinct modes of convection within the Earth, operate largely independently. Although plumes are secondary in terms of heat transport, they have probably played an important role in <span class="hlt">continental</span> geology. A new plume starts with a large spherical head that can cause uplift and flood basalt volcanism, and may be responsible for regional-scale metamorphism or crustal melting and varying amounts of crustal extension. Plume heads are followed by narrow tails that give rise to the familiar hot-spot tracks. The cumulative effect of processes associated with tail volcanism may also significantly affect <span class="hlt">continental</span> crust. PMID:17744717</p> <div class="credits"> <p class="dwt_author">Hill, R I; Campbell, I H; Davies, G F; Griffiths, R W</p> <p class="dwt_publisher"></p> <p class="publishDate">1992-04-10</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">96</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://eric.ed.gov/?q=plate+AND+tectonics&id=EJ638017"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: A Paradigm under Threat.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">|Discusses the challenges confronting <span class="hlt">plate</span> tectonics. Presents evidence that contradicts <span class="hlt">continental</span> drift, seafloor spreading, and subduction. Reviews problems posed by vertical tectonic movements. (Contains 242 references.) (DDR)|</p> <div class="credits"> <p class="dwt_author">Pratt, David</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">97</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.G33B0636N"> <span id="translatedtitle">Investigation of the inferred <span class="hlt">continental</span> flexure in the west of India and the non-rigidity of the oceanic part of the Indian <span class="hlt">plate</span> by episodic GPS Campaigns at Lakshadweep Islands along the Chagos-Laccadive ridge</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Three Episodic GPS campaigns were carried out at Lakshadweep islands with the objectives of reaffirming the inferred <span class="hlt">continental</span> flexure in the south-west of India, refining the already estimated strain accumulation in the south of Indian peninsula, and investigating the rigidity of larger oceanic part of the Indian <span class="hlt">plate</span>. The islands Kavaratti, the northern most island Chetlat and the southern most island Minicoy were chosen. With the new state-of-the-art GNSS receivers, which could track 30 GPS and 11 GLONASS Satellites with 5deg elevation mask, GNSS measurements were carried out during 2007 simultaneously in all these islands. They were reoccupied during 2008 and 2009.The acquired data was processed using Bernese 5.0 in the latest ITRF 2005 reference Frame. The site coordinates of Kavaratti, Chetlat and Minicoy and also the baseline lengths between Hyderabad and these three sites were estimated in the Global Network Solution. The estimated baseline length between Hyderabad and Kavaratti is 991, 303.3067 ± 0.0082m. The estimated baseline length between Hyderabad and Chetlat is 892, 216.5594 ± 0.0040m. The estimated baseline length between Hyderabad and Minicoy is 1171, 071.8777 ± 0.0065m. The estimated accuracy of the baseline length is in the range of 4 to 8 mm, which shows the quality of data processing. These studies across a 1,200-km-long "strain gauge" that is optimally oriented almost parallel to the compression seen on the land would enable the understanding whether this is due to the Himalayan collision, or the extension of the Capricorn-India diffuse boundary that could have extended this far north. Key words: GNSS, Episodic GPS Campaign, Strain gauge, <span class="hlt">Plate</span> rigidity</p> <div class="credits"> <p class="dwt_author">Narayana Babu, R. N.; Ec, M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">98</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/41948670"> <span id="translatedtitle">Tectonic stress in the <span class="hlt">plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The state of stress in the lithosphere provides strong constraints on the forces acting on the <span class="hlt">plates</span>. The directions of principal stresses in the <span class="hlt">plates</span> as indicated by midplate earthquake mechanisms, in situ stress measurements, and stress-sensitive geological features are used to test <span class="hlt">plate</span> tectonic driving force models. Force models include buoyancy forces at ridges, subduction zones, and <span class="hlt">continental</span> convergence</p> <div class="credits"> <p class="dwt_author">Randall M. Richardson; Sean C. Solomon; Norman H. Sleep</p> <p class="dwt_publisher"></p> <p class="publishDate">1979-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">99</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/introgeo/conceptests/examples/tectonic.html"> <span id="translatedtitle">ConcepTest: <span class="hlt">Plate</span> Tectonic Theory</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Which of the following statements is not consistent with <span class="hlt">plate</span> tectonic theory? a. <span class="hlt">Continental</span> crust is generally older than oceanic crust. b. The number of <span class="hlt">plates</span> has changed through time. c. Mountain chains are ...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">100</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1986GeoRL..13..456F"> <span id="translatedtitle"><span class="hlt">Plate</span> motion controls on back-arc spreading</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The motions of the subducting and the <span class="hlt">overriding</span> <span class="hlt">plates</span> influence the spatial and temporal distribution of back-arc spreading. Cenozoic <span class="hlt">plate</span> motions in hot spot-fixed and no-net-rotation reference frames were studied with attention to correlations between changes in motion and episodes of back-arc spreading in the western Pacific. The results suggest that major back-arc opening occurs when both the <span class="hlt">overriding</span> <span class="hlt">plate</span> retreats from the trench in an absolute sense and the subducting <span class="hlt">plate</span> undergoes a significant speed-up. Neither phenomenon alone is sufficient to initiate spreading. Three major <span class="hlt">plate</span> velocity increases can be identified in the Cenozoic: (1) the Pacific <span class="hlt">plate</span> 5-9 Ma; (2) the Indian <span class="hlt">plate</span> at 27 Ma; and (3) the Pacific <span class="hlt">plate</span> at 43 Ma, due to its shift from northerly to more westerly motion. At the present time, the Indian and Philippine are the only <span class="hlt">overriding</span> <span class="hlt">plates</span> that are retreating from their Pacific trenches and back-arc spreading occurs only on these two retreating <span class="hlt">plates</span>. Although the Indian <span class="hlt">plate</span> has been retreating for at least 25 Ma, back-arc spreading began only following the Pacific <span class="hlt">plate</span> speed-up 5-9 Ma. Earlier, during the Indian <span class="hlt">plate</span> speed-up, no <span class="hlt">overriding</span> <span class="hlt">plates</span> were retreating strongly and no back-arc spreading epsiodes are preserved from this time. For the earliest Pacific <span class="hlt">plate</span> shift at 43 Ma, the Eurasian <span class="hlt">plate</span> was not advancing, thus creating the only favorable <span class="hlt">plate</span> kinematic conditions in the Cenozoic for back-arc basin formation in this region. It is unclear whether extension in the Japan Sea is a result of these conditions.</p> <div class="credits"> <p class="dwt_author">Fein, J. B.; Jurdy, D. M.</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-05-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_4");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a style="font-weight: bold;">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_6");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_5 div --> <div id="page_6" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_5");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a style="font-weight: bold;">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_7");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">101</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1995JGR...10012357P"> <span id="translatedtitle">Shape of the subducted Rivera and Cocos <span class="hlt">plates</span> in southern Mexico: Seismic and tectonic implications</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The geometry of the subducted Rivera and Cocos <span class="hlt">plates</span> beneath the North American <span class="hlt">plate</span> in southern Mexico was determined based on the accurately located hypocenters of local and teleseismic earthquakes. The hypocenters of the teleseisms were relocated, and the focal depths of 21 events were constrained using a body wave inversion scheme. The suduction in southern Mexico may be approximated as a subhorizontal slab bounded at the edges by the steep subduction geometry of the Cocos <span class="hlt">plate</span> beneath the Caribbean <span class="hlt">plate</span> to the east and of the Rivera <span class="hlt">plate</span> beneath North America to the west. The dip of the interplate contact geometry is constant to a depth of 30 km, and lateral changes in the dip of the subducted <span class="hlt">plate</span> are only observed once it is decoupled from the <span class="hlt">overriding</span> <span class="hlt">plate</span>. On the basis of the seismicity, the focal mechanisms, and the geometry of the downgoing slab, southern Mexico may be segmented into four regions: (1) the Jalisco region to the west, where the Rivera <span class="hlt">plate</span> subducts at a steep angle that resembles the geometry of the Cocos <span class="hlt">plate</span> beneath the Caribbean <span class="hlt">plate</span> in Central America; (2) the Michoacan region, where the dip angle of the Cocos <span class="hlt">plate</span> decreases gradually toward the southeast, (3) the Guerrero-Oaxaca region, bounded approximately by the onshore projection of the Orozco and O'Gorman fracture zones, where the subducted slab is almost subhorizontal and underplates the upper <span class="hlt">continental</span> <span class="hlt">plate</span> for about 250 km, and (4) the southern Oaxaca and Chiapas region, in southeastern Mexico, where the dip of the subduction gradually increases to a steeper subduction in Central America. These drastic changes in dip do not appear to take place on tear faults, suggesting that smooth contortions accommodate these changes in geometry. The inferred 80 and 100 km depth contours of the subducted slab lie beneath the southern front of the Trans-Mexican Volcanic Belt, suggesting it is directly related to the subduction. Thus the observed nonparallelism with the Middle American Trench is apparently due to the changing geometry of the Rivera and Cocos <span class="hlt">plates</span> beneath the North American <span class="hlt">plate</span> in southern Mexico, and not to zones of weakness in the crust of the North American <span class="hlt">plate</span> as some authors have suggested.</p> <div class="credits"> <p class="dwt_author">Pardo, Mario; SuáRez, Gerardo</p> <p class="dwt_publisher"></p> <p class="publishDate">1995-07-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">102</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008AGUFM.V41F..06B"> <span id="translatedtitle">Seismic Evidence for Orthopyroxene Enrichment in <span class="hlt">Continental</span> Lithosphere Associated With Active Subduction</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">One of the long-standing questions regarding mantle recycling is the role of sediment subduction on the silica enrichment of the <span class="hlt">continental</span> lithosphere. Silica enrichment of the continetal lithosphere has been observed in a number of tectonic settings. Some of these settings are no longer associated with subduction, such as the Kaapvaal craton, where orthopyroxene enriched xenoliths bear evidence of some ancient silica enriching metasomatic event, or the Colorado Plateau, where similar orthopyroxene enriched xenoliths have been attributed to the paleosubduction of the Farallon <span class="hlt">plate</span>. However, because these areas are not currently located above a seismically active subducting <span class="hlt">plate</span>, seismic imaging of these lithospheres has been limited to relative P and S wave velocity deviations from teleseismic body wave tomography, and absolute S wave velocities from surface waves. The absence of absolute P-wave velocities makes determining the Vp/Vs ratios of the mantle lithospheres in these areas very difficult, in turn making it difficult to identify compositional variations that may be present. We have identified an area currently undergoing a silica enrichment event which is presently underlain by a very seismically active horizontally subducting <span class="hlt">plate</span>. The flat slab in central Chile and Argentina has long been considered a potential analogue to Rocky Mountain deformation in the western U.S. because of its association with the thick skinned uplifts of the Sierras Pampeanas. Seismic tomography results, both local P, S, and Vp/Vs body wave tomography results and surface wave tomography results, indicate that the mantle trapped between the top of the flat subducted Nazca <span class="hlt">plate</span> at 100 km depth and the base of the <span class="hlt">overriding</span> South American crust is characterized by unusually high S-wave velocities and unusually low Vp/Vs ratios. We demonstrate that while using seismic velocities and the Vp/Vs ratio to constrain melt depletion level may be difficult, it is possible to identify areas of silica enrichment by the corresponding low Vp/Vs ratios that result from the addition of either enstatite and/or quartz. The geometry of the low Vp/Vs anomaly is closely aligned with the orientation of the current flat-slab segment of the Nazca <span class="hlt">plate</span>, possibly suggesting a causal relationship between shallow or flat subduction and silica enrichment in the <span class="hlt">continental</span> lithosphere. This may have widespread implications on our understanding of the formation of stable mantle lithosphere such as those found beneath the Colorado Plateau or the Kaapvaal craton.</p> <div class="credits"> <p class="dwt_author">Beck, S. L.; Wagner, L. S.; Calkins, J.; Jackson, J. M.; Zandt, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">103</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1986EOSTr..67.1328R"> <span id="translatedtitle"><span class="hlt">Continental</span> Rifts</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary"><span class="hlt">Continental</span> Rifts, edited by A. M. Quennell, is a new member of the Benchmark Papers in Geology Series, edited in toto by R. W. Fairbridge. In this series the individual volume editors peruse the literature on a given topic, select a few dozen papers of ostensibly benchmark quality, and then reorder them in some sensible fashion. Some of the original papers are republished intact, but many are chopped into “McNuggets™” of information. Depending upon the volume editor, the chopping process can range from a butchering job to careful and prudent pruning. The collecting, sifting, and reorganizing tasks are, of course, equally editor-sensitive. The end product of this series is something akin to a set of Reader's Digest of Geology.</p> <div class="credits"> <p class="dwt_author">Rosendahl, B. R.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">104</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2501106"> <span id="translatedtitle">Cisplatin Damage <span class="hlt">Overrides</span> the Predefined Rotational Setting of Positioned Nucleosomes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">Cisplatin and carboplatin are used successfully to treat various types of cancer. The drugs target the nucleosomes of cancer cells and form intrastrand DNA cross-links that are located in the major groove. We constructed two site-specifically modified nucleosomes containing defined intrastrand cis-{Pt(NH3)2}2+ 1,3-d(GpTpG) cross-links. Histones from HeLa-S3 cancer cells were transferred onto synthetic DNA duplexes having nucleosome positioning sequences. The structures of these complexes were investigated by hydroxyl radical footprinting. Employing nucleosome positioning sequences allowed us to quantify the structural deviation induced by the cisplatin adduct. Our experiments demonstrate that a platinum cross-link locally <span class="hlt">overrides</span> the rotational setting predefined in the nucleosome positioning sequence such that the lesion faces toward the histone core. Identical results were obtained for two DNA duplexes in which the sites of platination differed by approximately half a helical turn. Additionally, we determined that cisplatin unwinds nucleosomal DNA globally by approximately 24°. The intrastrand cis-{Pt(NH3)2}2+ 1,3-d(GpTpG) cross-links are located in an area of the nucleosome that contains locally overwound DNA in undamaged reference nucleosomes. Because most nucleosome positions in vivo are defined by the intrinsic DNA sequence, the ability of cisplatin to influence the structure of these positioned nucleosomes may be of physiological relevance.</p> <div class="credits"> <p class="dwt_author">Ober, Matthias; Lippard, Stephen J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">105</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/gc/gc0602/2005GC001061/2005GC001061.pdf"> <span id="translatedtitle"><span class="hlt">Overriding</span> <span class="hlt">plate</span> thinning in subduction zones: Localized convection induced by slab dehydration</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">In subduction zones, many observations indicate that the backarc thermal state is particularly hot and that the upper lithosphere is thin, even if no recent extension episode has occurred. This might result from free thermal convection favored by low viscosities in the hydrated mantle wedge. We perform 2-D numerical experiments of the convective mantle wedge interaction with both the downgoing</p> <div class="credits"> <p class="dwt_author">D. Arcay; M.-P. Doin; E. Tric; R. Bousquet; C. de Capitani</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">106</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..14.9967H"> <span id="translatedtitle">Cyclic arc regimes over subduction zones at constant <span class="hlt">plate</span> motion, due to folding over the 660 km transition zone. Insight from numerical models.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">As a starting point, a finite element benchmark of analogue models of subduction is presented, with strong visco-elastic <span class="hlt">plates</span> and a rigid 660 km depth mantle discontinuity. This numerical approach neglects mantle viscosity and assumes that <span class="hlt">plate</span> motion are contolled by "external" spatial constraints on the Earth's surface. Then, a relationship is established between such applied <span class="hlt">plate</span> kinematics, deformation in the <span class="hlt">overriding</span> <span class="hlt">plate</span> and slab geometry. From the analysis of several simulations, two different styles of subduction are obtained depending on the (applied) <span class="hlt">overriding</span> <span class="hlt">plate</span> velocity Vop: the slab lays forward on the 660 km discontinuity (style 1) if Vop>0, or else the slab lays backward (style 2). We also obtain a cyclic pattern with slab folding repeatedly on itself when Vsp>0 and 2Vop + Vsp >0 ( Vsp is the subducting <span class="hlt">plate</span> velocity). In this case, periods of shallow slab dip associated to compression in the <span class="hlt">overriding</span> <span class="hlt">plate</span> are followed by periods of slab steepening associated with relative extension in the <span class="hlt">overriding</span> <span class="hlt">plate</span>. The periodicity of folding is controlled by slab viscosity and subduction velocity. When accounting for a low viscosity zone in the <span class="hlt">overriding</span> <span class="hlt">plate</span>, trench motion decouples from the far-field velocity of the <span class="hlt">overriding</span> <span class="hlt">plate</span>, and becomes directly sensitive to the slab's deep dynamics, as already known from "free-subduction" models. In a case of cyclic style 2 with forward folding of the slab, this weak zone in the <span class="hlt">overriding</span> <span class="hlt">plate</span> tends to increase the amplitudes of stress oscillations (and trench motion), and to increase the folding periodicity in time. Therefore the strength of the <span class="hlt">overriding</span> <span class="hlt">plate</span> also directly controls the dynamics of subduction. A model accounting for the Nazca and South American <span class="hlt">plates</span> velocities produces cycles with a period of ca. 22 Ma and a minimal dip angle of 10°. Despite the absence of a viscous mantle, this model might explain episods of volcanic quiescience alternating with episods of shortening along the Andean margin.</p> <div class="credits"> <p class="dwt_author">Hassani, R.; Gerbault, M.; Tric, E.; Gibert, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">107</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012CoMP..163..259D"> <span id="translatedtitle">Magmatic processes that generate chemically distinct silicic magmas in NW Costa Rica and the evolution of juvenile <span class="hlt">continental</span> crust in oceanic arcs</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Northwestern Costa Rica is built upon an oceanic plateau that has developed chemical and geophysical characteristics of the upper <span class="hlt">continental</span> crust. A major factor in converting the oceanic plateau to <span class="hlt">continental</span> crust is the production, evolution, and emplacement of silicic magmas. In Costa Rica, the Caribbean Large Igneous Province (CLIP) forms the <span class="hlt">overriding</span> <span class="hlt">plate</span> in the subduction of the Cocos <span class="hlt">Plate</span>—a process that has occurred for at least the last 25 my. Igneous rocks in Costa Rica older than about 8 Ma have chemical compositions typical of ocean island basalts and intra-oceanic arcs. In contrast, younger igneous deposits contain abundant silicic rocks, which are significantly enriched in SiO2, alkalis, and light rare-earth elements and are geochemically similar to the average upper <span class="hlt">continental</span> crust. Geophysical evidence (high Vp seismic velocities) also indicates a relatively thick (~40 km), addition of evolved igneous rocks to the CLIP. The silicic deposits of NW Costa Rica occur in two major compositional groups: a high-Ti and a low-Ti group with no overlap between the two. The major and trace element characteristics of these groups are consistent with these magmas being derived from liquids that were extracted from crystal mushes—either produced by crystallization or by partial melting of plutons near their solidi. In relative terms, the high-Ti silicic liquids were extracted from a hot, dry crystal mush with low oxygen fugacity, where plagioclase and pyroxene were the dominant phases crystallizing, along with lesser amounts of hornblende. In contrast, the low-Ti silicic liquids were extracted from a cool, wet crystal mush with high oxygen fugacity, where plagioclase and amphibole were the dominant phases crystallizing. The hot-dry-reducing magmas dominate the older sequence, but the youngest sequence contains only magmas from the cold-wet-oxidized group. Silicic volcanic deposits from other oceanic arcs (e.g., Izu-Bonin, Marianas) have chemical characteristics distinctly different from <span class="hlt">continental</span> crust, whereas the NW Costa Rican silicic deposits have chemical characteristics nearly identical to the upper <span class="hlt">continental</span> crust. The transition in NW Costa Rica from mafic oceanic arc and intra-oceanic magma to felsic, upper <span class="hlt">continental</span> crust-type magma is governed by a combination of several important factors that may be absent in other arc settings: (1) thermal maturation of the thick Caribbean plateau, (2) regional or local crustal extension, and (3) establishment of an upper crustal reservoir.</p> <div class="credits"> <p class="dwt_author">Deering, Chad D.; Vogel, Thomas A.; Patino, Lina C.; Szymanski, David W.; Alvarado, Guillermo E.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">108</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14793765"> <span id="translatedtitle">Iranian Geology and <span class="hlt">Continental</span> Drift in the Middle East</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This article summarizes Iranian geology and <span class="hlt">continental</span> drift in the Middle East. The relation of the two suggests that <span class="hlt">plate</span> tectonics satisfactorily explain the geological development of the Middle East.</p> <div class="credits"> <p class="dwt_author">Manoochehr Takin</p> <p class="dwt_publisher"></p> <p class="publishDate">1972-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">109</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008AGUFM.G21A0681N"> <span id="translatedtitle">Episodic GPS Campaigns at Lakshadweep Islands Along the Chagos-Laccadive Ridge to Investigate the Inferred <span class="hlt">Continental</span> Flexure in the West of India and the Non-Rigidity of the Oceanic Part of the Indian <span class="hlt">Plate</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Episodic GPS campaigns were initiated at Lakshadweep islands for the first time in India by National Geophysical Research Institute (NGRI) with the objectives of refining the already estimated strain accumulation in the south of Indian peninsula, reaffirming the inferred <span class="hlt">continental</span> flexure in the south-west of India, and investigating the rigidity of larger oceanic part of the Indian <span class="hlt">plate</span>. To start with two sites Kavaratti and the northern most island Chetlat were chosen. With the new state-of-the-art GNSS receivers, which could track 30 GPS and 11 GLONASS Satellites with 5° elevation mask, GPS measurements were carried out simultaneously at both Kavaratti and Chetlat for two weeks during March 2007 and repeat measurements were carried out recently in these islands. In February 2008 the southern most island Minicoy also was included in the experiment design and simultaneous GPS measurements were carried out in both Minicoy and Kavaratti. The acquired data was processed in the latest ITRF 2005 reference Frame. The site coordinates of Kavaratti, Chetlat and Minicoy and also the baseline lengths between Hyderabad and these three sites were estimated in the Global Network Solution. The methodology involved, the results of estimated site coordinates and the baseline lengths between Hyderabad and these islands are discussed in this paper. The estimated baseline length between Hyderabad and Kavaratti is 991,303.3067± 0.0082m. The 8mm accuracy in the estimation of baseline length shows the quality of data processing. The estimated baseline length between Hyderabad and Chetlat is 892,216.5594± 0.0040m. The estimated baseline length between Hyderabad and Minicoy is 1171,071.8777± 0.0065m. The estimated accuracy of the baseline length is in the range of 4to8mm. These studies across a 1,200-km-long "strain gauge" that is optimally oriented almost parallel to the compression seen on the land would enable the understanding whether this is due to the Himalayan collision, or the extension of the Capricorn-India diffuse boundary that could have extended this far north.</p> <div class="credits"> <p class="dwt_author">N, R.; Ec, M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">110</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://eric.ed.gov/?q=plate+AND+tectonics&id=EJ946756"> <span id="translatedtitle">The <span class="hlt">Plate</span> Tectonics Project</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">|The <span class="hlt">Plate</span> Tectonics Project is a multiday, inquiry-based unit that facilitates students as self-motivated learners. Reliable Web sites are offered to assist with lessons, and a summative rubric is used to facilitate the holistic nature of the project. After each topic (parts of the Earth, <span class="hlt">continental</span> drift, etc.) is covered, the students will…</p> <div class="credits"> <p class="dwt_author">Hein, Annamae J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">111</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=N8629426"> <span id="translatedtitle">Intraplate Deformation Due to <span class="hlt">Continental</span> Collisions: A Numerical Study of Deformation in a Thin Viscous Sheet.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary"><span class="hlt">Continental</span> collisions can result in the transmission of stress from the boundary between tectonic <span class="hlt">plates</span> into the <span class="hlt">plate</span> interiors. Extensive crustal deformations characterized by both horizontal and vertical crustal movements have occurred as a consequen...</p> <div class="credits"> <p class="dwt_author">S. C. Cohen R. C. Morgan</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">112</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/23624842"> <span id="translatedtitle">Centromere fragmentation is a common mitotic defect of S and G2 checkpoint <span class="hlt">override</span>.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">DNA damaging agents, including those used in the clinic, activate cell cycle checkpoints, which blocks entry into mitosis. Given that checkpoint <span class="hlt">override</span> results in cell death via mitotic catastrophe, inhibitors of the DNA damage checkpoint are actively being pursued as chemosensitization agents. Here we explored the effects of gemcitabine in combination with Chk1 inhibitors in a panel of pancreatic cancer cell lines and found variable abilities to <span class="hlt">override</span> the S phase checkpoint. In cells that were able to enter mitosis, the chromatin was extensively fragmented, as assessed by metaphase spreads and Comet assay. Notably, electron microscopy and high-resolution light microscopy showed that the kinetochores and centromeres appeared to be detached from the chromatin mass, in a manner reminiscent of mitosis with unreplicated genomes (MUGs). Cell lines that were unable to <span class="hlt">override</span> the S phase checkpoint were able to <span class="hlt">override</span> a G2 arrest induced by the alkylator MMS or the topoisomerase II inhibitors doxorubicin or etoposide. Interestingly, checkpoint <span class="hlt">override</span> from the topoisomerase II inhibitors generated fragmented kinetochores (MUGs) due to unreplicated centromeres. Our studies show that kinetochore and centromere fragmentation is a defining feature of checkpoint <span class="hlt">override</span> and suggests that loss of cell viability is due in part to acentric genomes. Furthermore, given the greater efficacy of forcing cells into premature mitosis from topoisomerase II-mediated arrest as compared with gemcitabine-mediated arrest, topoisomerase II inhibitors maybe more suitable when used in combination with checkpoint inhibitors. PMID:23624842</p> <div class="credits"> <p class="dwt_author">Beeharry, Neil; Rattner, Jerome B; Caviston, Juliane P; Yen, Tim</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-24</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">113</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012GeoJI.188..779L"> <span id="translatedtitle">The initiation of subduction by crustal extension at a <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We investigate how subduction may be triggered by <span class="hlt">continental</span> crust extension at a <span class="hlt">continental</span> margin. The large topography contrast between <span class="hlt">continental</span> and oceanic domains drives the spreading of <span class="hlt">continental</span> crust over oceanic basement. Subduction requires the oceanic <span class="hlt">plate</span> to get submerged in mantle, so that negative buoyancy forces may take over and drive further descent. This is promoted by two mechanisms. Loading by <span class="hlt">continental</span> crust bends the oceanic <span class="hlt">plate</span> downwards. Extension in the <span class="hlt">continental</span> domain induces crustal thinning, which acts to raise mantle above the oceanic <span class="hlt">plate</span>. In this model, the width of the <span class="hlt">continental</span> region undergoing extension is an important control parameter. The main physical controls are illustrated by laboratory experiments and simple theory for elastic flexure coupled to viscous crustal spreading. Three governing dimensionless parameters are identified. One involves the poorly constrained oceanic <span class="hlt">plate</span> buoyancy. We find that the oceanic <span class="hlt">plate</span> can be thrust to depths larger than 40 km even if it is buoyant, enabling metamorphic reactions and density increase in the oceanic crust. Another parameter is the ratio between the width of the <span class="hlt">continental</span> extension region and the flexural parameter for the oceanic <span class="hlt">plate</span>. Initiating subduction is easier if the continent thins over a short lateral distance or if the oceanic <span class="hlt">plate</span> is strong. The third important parameter is the ratio of oceanic <span class="hlt">plate</span> thickness to initial <span class="hlt">continental</span> crust thickness, such that a weak <span class="hlt">plate</span> and a thick crust do not favour subduction. Thus, the change from a passive to an active margin depends on the local characteristics of the <span class="hlt">continental</span> crust and is not determined solely by the age and properties of the oceanic lithosphere. It is shown that the spreading of <span class="hlt">continental</span> crust induces uplift of the margin as the adjacent seafloor subsides. Evidence for the emplacement of <span class="hlt">continental</span> crust over oceanic basement at passive margins is reviewed.</p> <div class="credits"> <p class="dwt_author">Lévy, F.; Jaupart, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-03-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">114</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42501919"> <span id="translatedtitle">What is <span class="hlt">continental</span> philosophy?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This paper attempts to provide an account of what is philosophically distinctive about what has come to be known as ‘<span class="hlt">Continental</span> philosophy’. In the early parts of the paper I give a historical and cultural analysis of the emergence of <span class="hlt">Continental</span> philosophy and consider objections to the latter and some stereotypical representations of the analytic?<span class="hlt">Continental</span> divide.In the philosophically more substantial</p> <div class="credits"> <p class="dwt_author">Simon Critchley</p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">115</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18256668"> <span id="translatedtitle">Geological record of fluid flow and seismogenesis along an erosive subducting <span class="hlt">plate</span> boundary.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Tectonic erosion of the <span class="hlt">overriding</span> <span class="hlt">plate</span> by the downgoing slab is believed to occur at half the Earth's subduction zones. In situ investigation of the geological processes at active erosive margins is extremely difficult owing to the deep marine environment and the net loss of forearc crust to deeper levels in the subduction zone. Until now, a fossil erosive subduction channel-the shear zone marking the <span class="hlt">plate</span> boundary-has not been recognized in the field, so that seismic observations have provided the only information on <span class="hlt">plate</span> boundary processes at erosive margins. Here we show that a fossil erosive margin is preserved in the Northern Apennines of Italy. It formed during the Tertiary transition from oceanic subduction to <span class="hlt">continental</span> collision, and was preserved by the late deactivation and fossilization of the <span class="hlt">plate</span> boundary. The outcropping erosive subduction channel is approximately 500 m thick. It is representative of the first 5 km of depth, with its deeper portions reaching approximately 150 degrees C. The fossil zone records several surprises. Two décollements were simultaneously active at the top and base of the subduction channel. Both deeper basal erosion and near-surface frontal erosion occurred. At shallow depths extension was a key deformation component within this erosive convergent <span class="hlt">plate</span> boundary, and slip occurred without an observable fluid pressure cycle. At depths greater than about 3 km a fluid cycle is clearly shown by the development of veins and the alternation of fast (co-seismic) and slow (inter-seismic) slip. In the deepest portions of the outcropping subduction channel, extension is finally overprinted by compressional structures. In modern subduction zones the onset of seismic activity is believed to occur at approximately 150 degrees C, but in the fossil channel the onset occurred at cooler palaeo-temperatures. PMID:18256668</p> <div class="credits"> <p class="dwt_author">Vannucchi, Paola; Remitti, Francesca; Bettelli, Giuseppe</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">116</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.T33E..07B"> <span id="translatedtitle">2-D tomographic imaging of <span class="hlt">continental</span> crust and relic slab beneath Baja California</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Rifting of Baja California from the margin of North America began as, or sometime before, subduction of the Farallon <span class="hlt">plate</span> ceased (~12 Ma). Many have speculated that increased coupling between the subducted Farallon slab and <span class="hlt">overriding</span> <span class="hlt">plate</span> caused the young upper part of the subducted <span class="hlt">plate</span> to detach from the older, colder, sinking slab. Then as the fragments of the Farallon <span class="hlt">plate</span> took on Pacific <span class="hlt">plate</span> motion, traction forces between the relic slab and Baja influenced rift localization in the Gulf of California. To better understand the processes that led to rifting of the Baja peninsula a 350 km seismic refraction/reflection profile was collected in 2002 in an effort to constrain the crustal thickness, the extent of relic slab beneath Baja California and the upper mantle P-wave velocities. The line spans the Baja Peninsula from the paleo-trench to the central Gulf of California, between the Farallon and Pescadero basins. 13 Ocean-Bottom Seismometers and 8 onshore Ref-Tek portable seismometers recorded 35,504 airgun shots from the R/V Ewing. Multichannel seismic (MCS) reflection profiles were collected on either side of the peninsula, providing information on the upper crustal structure and style of post-subduction deformation, particularly along the Tosco-Abreojos and Santa Margarita-San Lazaro fault systems. Here we present the integrated results of the MCS profiles and 2-D travel time tomography. Ray tracing was performed on 13,388 arrival picks, including Pg, Pn and PmP arrivals. Initial tomographic inversions reveal a crustal root beneath Baja California with an average velocity of 6.0 km/s. <span class="hlt">Continental</span> crust thins to the east into the Gulf of California and has a velocity structure consistent with that of the Alarcon segment of the PESCADOR experiment. Perhaps the most significant observation is an ~6 km thick, 8° east-dipping high velocity zone (mean of 6.7 km/s) that underplates the western Baja margin and extends at least 60 km from the former trench (~40 km west of the shoreline). We interpret this to be relic oceanic crust. We are investigating the extent of the relic slab beneath Baja and its relationship with high-Mg adakitic volcanics exposed on Isla Margarita, ~20 km north of the seismic transect. The existence of a stalled slab beneath the Baja margin suggests frictional and/or viscous coupling along the paleo-subduction interface is an important process in for the geodynamical development of the Gulf of California rift system.</p> <div class="credits"> <p class="dwt_author">Brothers, D. S.; Harding, A. J.; Kent, G.; Driscoll, N.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">117</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://supercronopio.es.ucl.ac.uk/~crlb/RESEARCH/PAPERS/ConradCLB04.pdf"> <span id="translatedtitle">The temporal evolution of <span class="hlt">plate</span> driving forces: Importance of ``slab suction'' versus ``slab pull'' during the Cenozoic</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Although mantle slabs ultimately drive <span class="hlt">plate</span> motions, the mechanism by which they do so remains unclear. A detached slab descending through the mantle will excite mantle flow that exerts shear tractions on the base of the surface <span class="hlt">plates</span>. This ``slab suction'' force drives subducting and <span class="hlt">overriding</span> <span class="hlt">plates</span> symmetrically toward subduction zones. Alternatively, cold, strong slabs may effectively transmit stresses to</p> <div class="credits"> <p class="dwt_author">Clinton P. Conrad; Carolina Lithgow-Bertelloni</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">118</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48902677"> <span id="translatedtitle">The temporal evolution of <span class="hlt">plate</span> driving forces: Importance of “slab suction” versus “slab pull” during the Cenozoic</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Although mantle slabs ultimately drive <span class="hlt">plate</span> motions, the mechanism by which they do so remains unclear. A detached slab descending through the mantle will excite mantle flow that exerts shear tractions on the base of the surface <span class="hlt">plates</span>. This “slab suction” force drives subducting and <span class="hlt">overriding</span> <span class="hlt">plates</span> symmetrically toward subduction zones. Alternatively, cold, strong slabs may effectively transmit stresses to</p> <div class="credits"> <p class="dwt_author">Clinton P. Conrad; Carolina Lithgow-Bertelloni</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">119</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012E%26PSL.355..283M"> <span id="translatedtitle">A global-scale <span class="hlt">plate</span> reorganization event at 105-100 Ma</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A major <span class="hlt">plate</span> reorganization is postulated to have occurred at approximately 100 Ma. However, this reorganization has received limited attention, despite being associated with the most prominent suite of fracture zone bends on the planet and many other geological events. We investigate tectonic events from the period ˜110 to 90 Ma and show that the reorganization occurred between 105 and 100 Ma, was global in scale, and affected all major <span class="hlt">plates</span>. Seafloor evidence for <span class="hlt">plate</span> motion changes is abundant during this period, with either fracture zone bends or terminations preserved in all ocean basins. Long-lived eastern Gondwanaland subduction ended along a 7000 km long section of the margin, while elsewhere around the proto-Pacific rim subduction continued and there is evidence that compressional stresses increased in the <span class="hlt">overriding</span> <span class="hlt">plates</span>. Thrusting in western North America, transpression and basin inversion in eastern Asia, and development of the present-day Andean-style margin along western South America occurred contemporaneous with the development of an extensional regime in eastern Gondwanaland. Basin instability in Africa and western Europe further demonstrates that lithospheric stress regime changes were widespread at this time. Considering the timing of the reorganization and the nature of associated <span class="hlt">plate</span> boundary changes, we suggest that eastern Gondwanaland subduction cessation is the most likely driving mechanism for the reorganization. Subduction is the dominant driver of <span class="hlt">plate</span> motion and therefore this event had the potential to strongly modify the balance of driving forces acting on the <span class="hlt">plates</span> in the southwestern proto-Pacific and neighboring <span class="hlt">plates</span>, whereby producing widespread changes in <span class="hlt">plate</span> motion and <span class="hlt">continental</span> lithospheric stress patterns. We propose that major changes in ridge-trench interaction triggered the cessation of subduction. The progressive subduction of two closely spaced perpendicular mid ocean ridges at the eastern Gondwanaland subduction zone, to the east of Australia and New Zealand, respectively, resulted in very young crust entering the trench and we suggest that by 105-100 Ma there was insufficient negative buoyancy to drive subduction. Finally, we propose that the plume push force of the Bouvet plume, that erupted near the African-Antarctic-South American triple junction, contributed to <span class="hlt">plate</span> motion changes in the southern Atlantic region.</p> <div class="credits"> <p class="dwt_author">Matthews, Kara J.; Seton, Maria; Müller, R. Dietmar</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-11-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">120</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFMDI52A..01D"> <span id="translatedtitle"><span class="hlt">Continental</span> lids and mantle convective stirring efficiency</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Interpreting surface geochemical data requires understanding the dynamic mechanisms that preserve or erase heterogeneities over geological times. Among these, the presence of <span class="hlt">continental</span> lids is known to have a first order impact on mantle convective dynamics and heat transfer. On Earth, oceanic <span class="hlt">plates</span> are recycled into the mantle and are characterized by a relatively strong heat flux, while continents are more insulating, lighter and therefore not subductable. Numerical and laboratory experiments have demonstrated that this dichotomy between continents and oceans can have a first order influence on mantle motion. One should therefore expect that this also influences the efficiency of convective stirring over billions of years. However, this effect has not been considered in previous studies that investigated mantle convective stirring efficiency. We have therefore investigated the influence of <span class="hlt">continental</span> lids on convective stirring efficiency using numerical experiments at infinite Prandtl number in a rectangular domain. Differences between oceanic and <span class="hlt">continental</span> <span class="hlt">plates</span> are accounted for by imposing heterogeneous surface boundary conditions for temperature and velocities: oceanic <span class="hlt">plates</span> are described by Dirichlet boundary conditions while continents are modeled as highly viscous, floating lids of variable extent, with locally imposed prescribed surface heat fluxes. We quantify the convective stirring efficiency using various diagnostics such as mixing time and Lyapunov exponent distribution. This numerical set up allows us to quantify systematically the influence of several governing parameters on the convective stirring efficiency: the Rayleigh number Ra, the horizontal extent of <span class="hlt">continental</span> lids, as well as viscous rheological parameters.</p> <div class="credits"> <p class="dwt_author">Deo, B.; Aleksandrov, V.; Samuel, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_5");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a style="font-weight: bold;">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_7");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_6 div --> <div id="page_7" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_6");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a style="font-weight: bold;">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_8");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">121</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://eric.ed.gov/?q=faults+AND+education+AND+system&pg=4&id=EJ409352"> <span id="translatedtitle">A Simple Class Exercise on <span class="hlt">Plate</span> Tectonic Motion.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p class="result-summary">|Presented is an activity in which students construct a model of <span class="hlt">plate</span> divergence with two sheets of paper to show the separation of two <span class="hlt">continental</span> <span class="hlt">plates</span> in a system of spreading ridges and faults. Diagrams and procedures are described. (CW)|</p> <div class="credits"> <p class="dwt_author">Bates, Denis E. B.</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">122</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://static.icr.org/i/pdf/technical/Catastrophic-Plate-Tectonics-A-Global-Flood-Model.pdf"> <span id="translatedtitle">Catastrophic <span class="hlt">Plate</span> Tectonics: A Global Flood Model of Earth History</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">In 1859 Antonio Snider proposed that rapid, horizontal divergence of crustal <span class="hlt">plates</span> occurred during Noah's Flood. Modern <span class="hlt">plate</span> tectonics theory is now conflated with assumptions of uniformity of rate and ideas of <span class="hlt">continental</span> \\</p> <div class="credits"> <p class="dwt_author">Steven A. Austin; John R. Baumgardner; D. Russell Humphreys; Andrew A. Snelling; Larry Vardiman; Kurt P. Wise</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">123</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48946216"> <span id="translatedtitle">Anatomy and formation of oblique <span class="hlt">continental</span> collision: South Falkland basin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The South Falkland basin is a partially filled Cenozoic foreland basin located south of the Falkland Plateau. It was formed by flexure of this southern edge of the South American <span class="hlt">plate</span> when the load represented by Burdwood Bank collided. This <span class="hlt">continental</span> fragment belongs to the predominantly oceanic Scotia <span class="hlt">plate</span>. Flexure probably started in early Cenozoic times and has continued to</p> <div class="credits"> <p class="dwt_author">Madeleine Bry; Nicky White; Satish Singh; Richard England; Carl Trowell</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">124</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.nsf-margins.org/Nuggets_Public/Nuggets_Final/RCL/McClusky_Reilinger_etal_Geodetic_Constraints.pdf"> <span id="translatedtitle">Geodetic constraints on <span class="hlt">continental</span> rifting along the Red Sea</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We are using the Global Positioning System (GPS) to monitor and quantify patterns and rates of tectonic and magmatic deformation associated with active rifting of the <span class="hlt">continental</span> lithosphere and the transition to sea floor spreading in the Red Sea. Broad-scale motions of the Nubian and Arabian <span class="hlt">plates</span> indicate coherent <span class="hlt">plate</span> motion with internal deformation below the current resolution of our</p> <div class="credits"> <p class="dwt_author">R. Reilinger; S. McClusky; A. Arrajehi; S. Mahmoud; A. Rayan; W. Ghebreab; G. Ogubazghi; A. Al-Aydrus</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">125</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://learningcenter.nsta.org/product_detail.aspx?id=10.2505/7/SCB-PT.3.1"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: <span class="hlt">Plate</span> Interactions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This Science Object is the fourth of five Science Objects in the <span class="hlt">Plate</span> Tectonic SciPack. It identifies the events that may occur and landscapes that form as a result of different <span class="hlt">plate</span> interactions. The areas along <span class="hlt">plate</span> margins are active. <span class="hlt">Plates</span> pushing against one another can cause earthquakes, volcanoes, mountain formation, and very deep ocean trenches. <span class="hlt">Plates</span> pulling apart from one another can cause smaller earthquakes, magma rising to the surface, volcanoes, and oceanic valleys and mountains from sea-floor spreading. <span class="hlt">Plates</span> sliding past one another can cause earthquakes and rock deformation. Learning Outcomes:� Explain why volcanoes and earthquakes occur along <span class="hlt">plate</span> boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of <span class="hlt">plate</span> interactions.</p> <div class="credits"> <p class="dwt_author">National Science Teachers Association (NSTA)</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-11-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">126</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008EOSTr..89...64K"> <span id="translatedtitle"><span class="hlt">Continental</span> Margins: Linking Ecosystems</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Impacts of Global, Local and Human Forcings on Biogeochemical Cycles and Ecosystems, IMBER/LOICZ <span class="hlt">Continental</span> Margins Open Science Conference; Shanghai, China, 17-21 September 2007; More than 100 scientists from 25 countries came together to address global, regional, local, and human pressures interactively affecting <span class="hlt">continental</span> margin biogeochemical cycles, marine food webs, and society. <span class="hlt">Continental</span> margins cover only 12% of the global ocean area yet account for more than 30% of global oceanic primary production. In addition, <span class="hlt">continental</span> margins are the most intensely used regions of the world's ocean for natural commodities, including productive fisheries and mineral and petroleum resources. The land adjacent to <span class="hlt">continental</span> margins hosts about 50% of the world's population, which will bear many direct impacts of global change on coastal margins. Understanding both natural and human-influenced alterations of biogeochemical cycles and ecosystems on <span class="hlt">continental</span> margins and the processes (including feedbacks) that threaten sustainability of these systems is therefore of global interest.</p> <div class="credits"> <p class="dwt_author">Kelly-Gerreyn, Boris; Rabalais, Nancy; Middelburg, Jack; Roy, Sylvie; Liu, Kon-Kee; Thomas, Helmuth; Zhang, Jing</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">127</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.T42C..05L"> <span id="translatedtitle">BOLIVAR & GEODINOS: Investigations of the Southern Caribbean <span class="hlt">Plate</span> Boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The southern Caribbean-South American <span class="hlt">plate</span> boundary has many similarities to California's San Andreas system: 1) The CAR-SA system consists of a series of strands of active right lateral strike-slip faults extending >1000 km from the Antilles subduction zone. This system has several names and includes the El Pilar, Coche, San Sebastian, Moron, and Oca faults. 2) The CAR-SA relative velocity has been about 20 mm/yr of mostly right lateral motion since about 55 Ma, giving a total displacement on the CAR-SA <span class="hlt">plate</span> boundary similar to that of the San Andreas system. 3) The <span class="hlt">plate</span> boundary has about 10% convergence in western SA, with less as one moves eastward due to relative convergence between North and South America. 4) The CAR-SA system has fold and thrust belts best developed continentward of the strike-slip faults, similar to the San Andreas. 5) There is a big bend in the CAR <span class="hlt">plate</span> boundary at approximately the same distance from the Antilles trench as the big bend in Southern California is from the Cascadia subduction zone. The tectonic origins of the CAR-SA <span class="hlt">plate</span> boundary and the San Andreas are very different, however, despite the similarities between the systems. Rather than impingement of a ridge on a trench, the CAR-SA system is thought to have resulted from a continuous oblique collision of the southern end of a Cretaceous island arc system with the northern edge of South America. During this process the CAR island arc and the modern CAR <span class="hlt">plate</span> overrode a proto-Caribbean <span class="hlt">plate</span> and destroyed a Mesozoic passive margin on the northern edge of SA. BOLIVAR and GEODINOS are multi-disciplinary investigations of the lithosphere and deeper structures associated with the diffuse CAR-SA <span class="hlt">plate</span> boundary zone. We review a number of observations regarding the <span class="hlt">plate</span> boundary obtained or confirmed from these studies: 1) The Caribbean Large Igneous Province, being overridden by the Maracaibo block in western Venezuela, can be identified beneath Aruba and coastal Venezuela, and is associated with broad uplift of the coastal regions. This is likely a site of <span class="hlt">continental</span> growth. 2) The accretionary wedge terranes of the Southern Caribbean Deformed Belt formed in the Neogene, and extend as far east as the Aves Ridge. They result from SA <span class="hlt">overriding</span> the CAR LIP, which for a number of reasons, we do not regard as normal subduction. 3) Igneous rocks on the islands of the Leeward Antilles arc, Aruba to Los Testigos, show a steady decrease in age from west to east (94.7-37.4 Ma), suggesting that the islands have been progressively captured from the Antilles arc by the <span class="hlt">plate</span> boundary during the prolonged island arc-continent collision. Terrane capture models thus far cannot completely explain the data. 4) High (> 6.5 km/s) P-velocity bodies are found in the shallow crust along the main strike-slip faults along much of the <span class="hlt">plate</span> boundary. We interpret these as elements of the HP/LT metamorphic terranes found in the adjacent thrust belts of central Venezuela. This suggests to us that displacement partitioning in the trench and subsequent strike-slip both play important roles in exhumation of the HP/LT terranes. 5) Crustal thickness variations in the <span class="hlt">plate</span> boundary region are large (> 10 km), of short spatial wavelength (< 100 km), and indicate that the highest elevations of the coastal mountain belts are not supported isostatically.</p> <div class="credits"> <p class="dwt_author">Levander, A.; Schmitz, M.; Working Groups, B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">128</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48952590"> <span id="translatedtitle">Some effects of anisotropy on velocity contrasts between subducting lithosphere and <span class="hlt">overriding</span> mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We compute velocity anisotropy for three models of preferred crystal alignment due to finite strain in the mantle which, when juxtaposed with computed anisotropy in subducted lithosphere and neglecting other effects, give velocity contrasts that we compare with those observed. We find a strong dip dependence for computed velocity contrasts due to slow axis alignment in the <span class="hlt">overriding</span> mantle perpendicular</p> <div class="credits"> <p class="dwt_author">Tom Shoberg; Craig R. Bina</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">129</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://home.comcast.net/~rhaberlin/ptmod.htm"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics Learning Module</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This <span class="hlt">plate</span> tectonics unit was designed to be used with a college course in physical geography. Subject matter covered includes: the development of the theory including Wegener's <span class="hlt">Continental</span> Drift Hypothesis and the existence of Pangaea, Harry Hess and his work on sea-floor spreading, and the final theory. It points out that global features such as deep oceanic trenches, mid-ocean ridges, volcanic activity, and the location of earthquake epicenters can now be related to the story of <span class="hlt">plate</span> tectonics, since most geological activity occurs along <span class="hlt">plate</span> boundaries. Divergent, convergent and transform <span class="hlt">plate</span> boundaries are discussed in detail. This module contains a study guide and outline notes, study questions, and practice quizzes. One feature of the module is a web exploration section with links to twelve outside sites that augment the instruction.</p> <div class="credits"> <p class="dwt_author">Haberlin, Rita</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">130</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://webspinners.com/dlblanc/tectonic/ptABCs.php"> <span id="translatedtitle">An Introduction to the ABCs of <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This introduction to <span class="hlt">plate</span> tectonics covers <span class="hlt">plates</span> and boundaries, subduction zones, colliding continents, plumes, and earthquakes. There is also more advanced material on buoyancy, floating continents, and rates of isostasy; sedimentation, <span class="hlt">continental</span> growth, rifts and creation of <span class="hlt">continental</span> margins, passive and active margins, and island arcs and back-arc basins; <span class="hlt">continental</span> collision, folding of sedimentary layers, and collision of cratons; and the mechanism of <span class="hlt">plate</span> tectonics including convective mantles, convection models, distribution of plumes, plume driven convection, <span class="hlt">plate</span> rifting models, and triple junctions.</p> <div class="credits"> <p class="dwt_author">Blanchard, Donald</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">131</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.springerlink.com/index/g7l126p314673055.pdf"> <span id="translatedtitle"><span class="hlt">Continental</span> margin off Western India and Deccan Large Igneous Province</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Massive, transient late syn-rift-to-breakup volcanism during separation between the Seychelles microcontinent and India formed the Deccan <span class="hlt">continental</span> flood basalts and their equivalents on the Seychelles-Mascarene Plateau and on the conjugate <span class="hlt">continental</span> margins, i.e. the Deccan Large Igneous Province. We estimate an original extrusive area of at least 1.8×106 km2, and a volume >1.8×106 km3, and suggest a <span class="hlt">plate</span> tectonic model comprising: (1) development</p> <div class="credits"> <p class="dwt_author">Axel Todal; Olav Edholm</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">132</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6270979"> <span id="translatedtitle">Oceanology of the antarctic <span class="hlt">continental</span> shelf: Volume 43</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">This book discusses the seas of the deep <span class="hlt">continental</span> shelf, which play an important climatic role in sea ice production, deep ocean ventilation and wastage of the Antarctic ice sheet. This volume includes analyses of measurements taken from ships and satellites, and from sea ice and glacial ice. High resolution profiling equipment, long term bottom-moored instruments, continuous remote sensors, geochemical tracers and computer models have provided the basis for new insights into the <span class="hlt">continental</span> shelf circulation. Color <span class="hlt">plates</span> and an accompanying GEBCO Circum-Antarctic map effectively portray the <span class="hlt">continental</span> shelf in relation to the glaciated continent, the sea ice and the surrounding Southern Ocean.</p> <div class="credits"> <p class="dwt_author">Jacobs, S.S.</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">133</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1987EOSTr..68..249P"> <span id="translatedtitle"><span class="hlt">Continental</span> Scientific Drilling Workshop</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Second <span class="hlt">Continental</span> Scientific Drilling Program Workshop took place June 12-14, 1986, on the campus of the South Dakota School of Mines and Technology in Rapid City. Like the workshop held in Houston a year earlier, the Rapid City workshop was sponsored by the Department of Energy (DOE), the National Science Foundation (NSF), and the U.S. Geological Survey (USGS). The NSF portion of the <span class="hlt">Continental</span> Scientific Drilling Program (CSDP) is administered by a consortium of 36 universities through a nonprofit corporation named Deep Observation and Sampling of the Earth' <span class="hlt">Continental</span> Crust, Inc., or more simply, DOSECC.</p> <div class="credits"> <p class="dwt_author">Papike, J. J.; Stehli, F. G.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">134</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52600019"> <span id="translatedtitle">Differential seafloor spreading of the North Atlantic and consequent deformation of adjacent <span class="hlt">continental</span> margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">One of the main assumptions of the theory of <span class="hlt">plate</span> tectonics is that all <span class="hlt">plates</span> are rigid. However, in some <span class="hlt">plate</span> reconstructions, the fits improve if the continents deform. Moreover, along parts of the North Atlantic <span class="hlt">continental</span> margins, there is good evidence for post-rift deformation, in the form of inverted basins and compressional domes. Possible causes of these features are</p> <div class="credits"> <p class="dwt_author">Eline Le Breton; Peter R. Cobbold; Pierrick Roperch; Olivier Dauteuil</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">135</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55703728"> <span id="translatedtitle">Rift to drift transition in Siberian Arctic and its impact on <span class="hlt">continental</span> margin architecture</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The East Siberian Arctic <span class="hlt">Continental</span> Margin (ESAM) represents a rare case of rifting to spreading transition. Present-day geodynamics of this <span class="hlt">plate</span> tectonic interplay is characterized by a very slow <span class="hlt">plate</span> divergence in the Laptev Sea as this regions is located just landward of the slowest spreading center worldwide (the Gakkel Ridge), close to the pole of North American\\/Eurasian <span class="hlt">plate</span> rotation.</p> <div class="credits"> <p class="dwt_author">S. S. Drachev</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">136</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52215589"> <span id="translatedtitle">Oblique Convergence under Increasing <span class="hlt">Plate</span>-Boundary Curvature: Pliocene-Holocene Partitioned Transtension in the Eastern Hellenic Forearc</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Deformation of an <span class="hlt">overriding</span> <span class="hlt">plate</span> varies along the strike of a convergent <span class="hlt">plate</span> boundary whose curvature is greater than that of the Earth. For the Hellenic <span class="hlt">plate</span> boundary, not only do relative <span class="hlt">plate</span>-convergence vectors vary spatially along strike, but the subduction-zone curvature has increased temporally as the trench migrated south-southwestward since Early Miocene time. Structural mapping\\/kinematic analyses, tectonostratigraphy, and chronostratigraphy</p> <div class="credits"> <p class="dwt_author">K. L. Kleinspehn; J. H. Ten Veen</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">137</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/53153277"> <span id="translatedtitle">Dynamics of active <span class="hlt">plate</span> margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">I have investigated the forces involved in driving large-scale <span class="hlt">continental</span> deformation in western North America and Central Asia. I have quantified the vertically averaged deviatoric stress field for both regions arising from internal buoyancy forces and the accommodation of relative <span class="hlt">plate</span> motions. These two driving forces act approximately equally in driving most of the observed deformation, while stresses arising from</p> <div class="credits"> <p class="dwt_author">Lucy Marie Flesch</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">138</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60206473"> <span id="translatedtitle">Vital outer <span class="hlt">continental</span> shelf</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The US <span class="hlt">Continental</span> Shelf has already yielded 5.4 billion barrels of crude oil and 49.2 trillion cubic feet of natural gas, but geologists estimate that 83 billion barrels of oil and 594 trillion cubic feet of gas remain to be tapped. The Outer <span class="hlt">Continental</span> Shelf lies beyond the three-mile state jurisdiction and is administered by the US government, except in</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">139</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42054049"> <span id="translatedtitle"><span class="hlt">Continental</span> scientific drilling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Deep Observation and Sampling of the Earth's <span class="hlt">Continental</span> Crust, Inc. (DOSECC), held its annual board and corporation meetings March 2-3 in Chandler, Ariz. DOSECC is the university consortium, supported by the National Science Foundation, that plans, coordinates and implements U.S. <span class="hlt">continental</span> scientific drilling.Actions taken at the meetings will enable DOSECC to continue to provide scientific and engineering support for NSF-approved</p> <div class="credits"> <p class="dwt_author">Melvin Friedman</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">140</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14803774"> <span id="translatedtitle">Manganese ore deposits and <span class="hlt">plate</span> tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">IT is now generally accepted that the oceanic crust and overlying pelagic sediments are enriched in several metals, including copper and manganese1-3. The theory of <span class="hlt">plate</span> tectonics has demonstrated that the oceanic lithosphere is likely to be remobilised or emplaced along convergent <span class="hlt">continental</span> margins through magmatic or tectonic activity. The <span class="hlt">plate</span> tectonic model has been used to explain the metallogenesis</p> <div class="credits"> <p class="dwt_author">Michael Thonis; ROGER G. BURNS</p> <p class="dwt_publisher"></p> <p class="publishDate">1975-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_6");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a style="font-weight: bold;">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_8");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_7 div --> <div id="page_8" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_7");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a style="font-weight: bold;">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_9");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">141</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/jb/v076/i005/JB076i005p01212/JB076i005p01212.pdf"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonic Eraplacement Upper Mantle Peridotires along</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Recently developed ideas of global tectonics have provided a new framework within which to consider the origin of alpine-type peridotites. In <span class="hlt">plate</span> theory, compressional zones associated with island arcs are considered to represent <span class="hlt">plate</span> boundaries where oceanic lithosphere is subducted. The subduction zones are characterized by lithospheric underthrusting, andesitic volcanoes, and deep seismic activity that generally dips under the <span class="hlt">continental</span></p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">142</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.imi.med.uni-erlangen.de/lehre/ws0405/medinfjclub_dateien/hsieh_et_alii_2004.pdf"> <span id="translatedtitle">Characteristics and Consequences of Drug Allergy Alert <span class="hlt">Overrides</span> in a Computerized Physician Order Entry System</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">ObjectiveThe aim of this study was to determine characteristics of drug allergy alert <span class="hlt">overrides</span>, assess how often they lead to preventable adverse drug events (ADEs), and suggest methods for improving the allergy-alerting system.DesignChart review was performed on a stratified random subset of all allergy alerts occurring during a 3-month period (August through October 2002) at a large academic hospital.MeasurementsFactors that</p> <div class="credits"> <p class="dwt_author">Tyken C. Hsieh; Gilad J. Kuperman; Tonushree Jaggi; Patricia Hojnowski-Diaz; Julie Fiskio; Deborah H. Williams; David W. Bates; Tejal K. Gandhi</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">143</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://geomaps.wr.usgs.gov/parks/pltec/"> <span id="translatedtitle">What on Earth is <span class="hlt">Plate</span> Tectonics?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This abbreviated explanation of the subject of <span class="hlt">plate</span> tectonics is divided into several parts. The first section, entitled Into the Earth, describes the crust, mantle and core of the Earth, while the next section shows a world map with the <span class="hlt">plates</span> delineated. The section called Action at the Edges uses text and diagrams to explain what is occurring at the <span class="hlt">plate</span> boundaries. Links lead to a detailed discussion of converging boundaries including ocean-ocean, ocean-<span class="hlt">continental</span>, and <span class="hlt">continental-continental</span>. A wide range illustration shows both surface and cross-section views of <span class="hlt">plate</span> interaction and a link leads to a similar diagram with labels. In the Moving through Time section, a series of color-coded maps is shown, illustrating the relative position of the continents over the past 650 million years. The last section shows a paleogeographic reconstruction of the Earth and explains how paleomagnetism, magnetic anomalies, paleobiogeography, paleoclimatology, and geologic history are used to create it.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2007-02-26</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">144</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/53232850"> <span id="translatedtitle">Deformation Patterns and Subduction Behavior of <span class="hlt">Continental</span> Lithosphere Entering a Trench</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We perform 2-D numerical simulations of <span class="hlt">continental</span> lithosphere entering a subduction zone, to better understand deformation patterns resulting from subduction of a <span class="hlt">continental</span> margin. The model consists of a subduction zone in which an attached slab drives subduction of a passive <span class="hlt">continental</span> margin beneath an oceanic <span class="hlt">plate</span>. A particle-based 2-D visco-elasto-plastic thermo-mechanical finite element code is employed to study the</p> <div class="credits"> <p class="dwt_author">C. E. Steedman; B. J. Kaus; T. W. Becker; D. Okaya</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">145</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48814443"> <span id="translatedtitle">Self-Organized Criticality in <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">\\u000a A review of scaling laws observed in earthquake processes (short time scale) and in <span class="hlt">plate</span> tectonics (large time scale) is\\u000a given. Laboratory experiments which model the mechanical deformations and ruptures of large <span class="hlt">continental</span> <span class="hlt">plates</span> are presented\\u000a and analyzed. Comparison with a field theory suggests that <span class="hlt">plate</span> tectonics maybe one of the best natural realization of self-organized\\u000a criticality, viewed front the</p> <div class="credits"> <p class="dwt_author">Didier Sornette</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">146</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40760574"> <span id="translatedtitle">Introduction to TETHYS—an interdisciplinary GIS database for studying <span class="hlt">continental</span> collisions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The TETHYS GIS database is being developed as a way to integrate relevant geologic, geophysical, geochemical, geochronologic, and remote sensing data bearing on Tethyan <span class="hlt">continental</span> <span class="hlt">plate</span> collisions. The project is predicated on a need for actualistic model ‘templates’ for interpreting the Earth's geologic record. Because of their time-transgressive character, Tethyan collisions offer ‘actualistic’ models for features such as <span class="hlt">continental</span> ‘escape’,</p> <div class="credits"> <p class="dwt_author">S. D. Khan; M. F. J. Flower; M. I. Sultan; E. Sandvol</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">147</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/255112"> <span id="translatedtitle">Initiation and propagation of shear zones in a heterogeneous <span class="hlt">continental</span> lithosphere</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Numerical methods were used to investigate the deformation of a <span class="hlt">continental</span> <span class="hlt">plate</span> in northeastern Brazil. Of particular interest are the perturbations induced by a stiff compressional deformation of a highly heterogeneous <span class="hlt">continental</span> lithosphere on the development of a shear zone formed at the termination of a stiff block.</p> <div class="credits"> <p class="dwt_author">Tommasi, A.; Vauchez, A. [CNRS/Universite de Montpellier II (France)</p> <p class="dwt_publisher"></p> <p class="publishDate">1995-11-10</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">148</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40851486"> <span id="translatedtitle">Preliminary three-dimensional model of mantle convection with deformable, mobile <span class="hlt">continental</span> lithosphere</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Characteristic tectonic structures such as young orogenic belts and suture zones in a continent are expected to be mechanically weaker than the stable part of the <span class="hlt">continental</span> lithosphere with the cratonic root (or cratonic lithosphere) and yield lateral viscosity variations in the <span class="hlt">continental</span> lithosphere. In the present-day Earth's lithosphere, the pre-existing, mechanically weak zones emerge as a diffuse <span class="hlt">plate</span> boundary.</p> <div class="credits"> <p class="dwt_author">Masaki Yoshida</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">149</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48934802"> <span id="translatedtitle">Intraplate seismicity, reactivation of preexisting zones of weakness, alkaline magmatism, and other tectonism postdating <span class="hlt">continental</span> fragmentation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The distribution of intraplate earthquakes and of igneous rocks postdating <span class="hlt">continental</span> rifting is summarized and placed into a <span class="hlt">plate</span> tectonic framework for the following <span class="hlt">continental</span> areas: eastern and central North America, Africa, Australia, Brazil, Greenland, Antarctica, Norway, Spitsbergen, India, and the margins of the Red Sea and Gulf of Aden. In continents, intraplate earthquakes tend to be concentrated along preexisting</p> <div class="credits"> <p class="dwt_author">Lynn R. Sykes</p> <p class="dwt_publisher"></p> <p class="publishDate">1978-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">150</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/59329880"> <span id="translatedtitle">Characteristics and effects of nurse dosing <span class="hlt">over-rides</span> on computer-based intensive insulin therapy protocol performance</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">ObjectiveTo determine characteristics and effects of nurse dosing <span class="hlt">over-rides</span> of a clinical decision support system (CDSS) for intensive insulin therapy (IIT) in critical care units.DesignRetrospective analysis of patient database records and ethnographic study of nurses using IIT CDSS.MeasurementsThe authors determined the frequency, direction—greater than recommended (GTR) and less than recommended (LTR)— and magnitude of <span class="hlt">over-rides</span>, and then compared recommended and</p> <div class="credits"> <p class="dwt_author">Thomas R Campion; Addison K May; Lemuel R Waitman; Asli Ozdas; Nancy M Lorenzi; Cynthia S Gadd</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">151</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40843552"> <span id="translatedtitle">Sediment deformation and <span class="hlt">plate</span> tectonics in the Gulf of Oman</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The <span class="hlt">continental</span> margin off the Makran coast of Iran and Pakistan is an excellent example of active deformation of sediments at a compressive <span class="hlt">plate</span> boundary. Seismic reflection profiles across the margin suggest that relatively flat-lying sediments from the Oman abyssal plain are being scraped off the Arabian <span class="hlt">plate</span> and accreted onto the Eurasian <span class="hlt">plate</span> in a series of tightly folded</p> <div class="credits"> <p class="dwt_author">R. S. White; K. Klitgord</p> <p class="dwt_publisher"></p> <p class="publishDate">1976-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">152</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1989EOSTr..70..180F"> <span id="translatedtitle"><span class="hlt">Continental</span> scientific drilling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Deep Observation and Sampling of the Earth's <span class="hlt">Continental</span> Crust, Inc. (DOSECC), held its annual board and corporation meetings March 2-3 in Chandler, Ariz. DOSECC is the university consortium, supported by the National Science Foundation, that plans, coordinates and implements U.S. <span class="hlt">continental</span> scientific drilling.Actions taken at the meetings will enable DOSECC to continue to provide scientific and engineering support for NSF-approved drilling projects and to participate in coordinated <span class="hlt">continental</span> scientific drilling program (CSDP) activities of NSF, the U.S. Geological Survey, and the Department of Energy. To facilitate development of a truly national CSDP, DOSECC member representatives unanimously agreed to broaden the consortium membership to include nonuniversity entities of the Earth sciences community from private industry, state geological surveys, and government and national laboratories. Interested parties can obtain information on Affiliate Membership from DOSECC's Washington office (1755 Massachusetts Avenue N.W., Suite 700, Washington, DC 20036-2102, tel. 202-234-2100).</p> <div class="credits"> <p class="dwt_author">Friedman, Melvin</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">153</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006RvGeo..44.4002S"> <span id="translatedtitle">Subduction evolution and mantle dynamics at a <span class="hlt">continental</span> margin: Central North Island, New Zealand</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Central North Island, New Zealand, provides an unusually complete geological and geophysical record of the onset and evolution of subduction at a <span class="hlt">continental</span> margin. Whereas most subduction zones are innately two-dimensional, North Island of New Zealand displays a distinct three-dimensional character in the back-arc regions. Specifically, we observe "Mariana-type" subduction in the back-arc areas of central North Island in the sense of back-arc extension, high heat flow, prolific volcanism, geothermal activity, and active doming and exhumation of the solid surface. Evidence for emplacement of a significant percent of new lithosphere beneath the central North Island comes from heat flux of 25 MW/km of strike (of volcanic zone) and thinned crust underlain by rocks with a seismic wave speed consistent with underplated new crust. Seismic attenuation (Qp-1) is high (˜240), and rhyolitic and andesitic volcanism are widespread. Almost complete removal of mantle lithosphere is inferred here in Pliocene times on the basis of the rock uplift history and upper mantle seismic velocities as low as 7.4 ± 0.1 km/s. In contrast, southwestern North Island exhibits "Chilean-type" back-arc activity in the sense of compressive tectonics, reverse faulting, low-heat-flow, thickened lithosphere, and strong coupling between the subducted and <span class="hlt">overriding</span> <span class="hlt">plates</span>. This rapid switch from Mariana-type to Chilean-type subduction occurs despite the age of the subducted <span class="hlt">plate</span> being constant under North Island. Moreover, stratigraphic evidence shows that processes that define the extensional back-arc area (the Central Volcanic Region) are advancing southward into the compressional system (Wanganui Basin) at about 10 mm/yr. We link the progression from one system to another to a gradual and viscous removal of thickened mantle lithosphere in the back-arc regions. Thickening occurred during the Miocene within the Taranaki Fault Zone. The process of thickening and convective removal is time- and temperature-dependent and has left an imprint in both the geological record and geophysical properties of central North Island, which we document and describe.</p> <div class="credits"> <p class="dwt_author">Stern, T. A.; Stratford, W. R.; Salmon, M. L.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">154</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013E%26PSL.381..166H"> <span id="translatedtitle">The extent of <span class="hlt">continental</span> crust beneath the Seychelles</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The granitic islands of the Seychelles Plateau have long been recognised to overlie <span class="hlt">continental</span> crust, isolated from Madagascar and India during the formation of the Indian Ocean. However, to date the extent of <span class="hlt">continental</span> crust beneath the Seychelles region remains unknown. This is particularly true beneath the Mascarene Basin between the Seychelles Plateau and Madagascar and beneath the Amirante Arc. Constraining the size and shape of the Seychelles <span class="hlt">continental</span> fragment is needed for accurate <span class="hlt">plate</span> reconstructions of the breakup of Gondwana and has implications for the processes of <span class="hlt">continental</span> breakup in general. Here we present new estimates of crustal thickness and VP/VS from H–? stacking of receiver functions from a year long deployment of seismic stations across the Seychelles covering the topographic plateau, the Amirante Ridge and the northern Mascarene Basin. These results, combined with gravity modelling of historical ship track data, confirm that <span class="hlt">continental</span> crust is present beneath the Seychelles Plateau. This is ˜30–33 km thick, but with a relatively high velocity lower crustal layer. This layer thins southwards from ˜10 km to ˜1 km over a distance of ˜50 km, which is consistent with the Seychelles being at the edge of the Deccan plume prior to its separation from India. In contrast, the majority of the Seychelles Islands away from the topographic plateau show no direct evidence for <span class="hlt">continental</span> crust. The exception to this is the island of Desroche on the northern Amirante Ridge, where thicker low density crust, consistent with a block of <span class="hlt">continental</span> material is present. We suggest that the northern Amirantes are likely <span class="hlt">continental</span> in nature and that small fragments of <span class="hlt">continental</span> material are a common feature of plume affected <span class="hlt">continental</span> breakup.</p> <div class="credits"> <p class="dwt_author">Hammond, J. O. S.; Kendall, J.-M.; Collier, J. S.; Rümpker, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">155</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007epsc.conf..955G"> <span id="translatedtitle"><span class="hlt">Continental</span> rifting on Earth and Mars - A comparison</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The formation of <span class="hlt">continental</span> rift systems on Earth is connected to prerift uplift generated by upwelling mantle plumes and extensional stresses which originate from remote <span class="hlt">plate</span> boundary forces. <span class="hlt">Continental</span> rifting and <span class="hlt">continental</span> breakup on Earth are therefore intimately connected to Earth's <span class="hlt">plate</span> tectonic environment. Recently, Martian candidate analogues to terrestrial <span class="hlt">continental</span> rifts have been investigated in detail and it has been shown that the Tempe Fossae, Acheron Fossae and Thaumasia Highland Rifts bear many structural similarities to <span class="hlt">continental</span> rifts on Earth. However, the question of the rift formation process has so far not been addressed and an active mechanism involving mantle plumes and local doming has usually been assumed. Rifts are also sometimes thought to be at least indirect evidence for <span class="hlt">plate</span> tectonics, although the connection of Martian rifts to <span class="hlt">plate</span> tectonic forces has so far not been discussed. We have investigated whether forces connected to <span class="hlt">plate</span> movement are necessary to initiate rifting and show that lithosphere scale faulting at the Thaumasia Highland Rift is feasible even in the absence of mantle plumes or tensional <span class="hlt">plate</span>-boundary forces. Rather, stresses originating from horizontal differences of the gravitational potential energy will be shown to be almost sufficient to induce rifting, supporting the hypothesis of a passive rifting mechanism in the Thaumasia Highlands. The emplacement of magma bodies in the upper crust could then sufficiently weaken the lithosphere to initiate lithosphere scale faulting and thus induce rifting. This hypothesis is in good agreement with the observation of rift-related volcanism as well as the fact that faults seem to initiate at volcanoes and propagate away from them before interconnecting. We conclude that rifting on Mars is feasible even if key factors connected to <span class="hlt">continental</span> rifting on Earth, i.e. <span class="hlt">plate</span> boundary forces and convection induced drag on the lower lithosphere, are absent. The absence of forces connected to <span class="hlt">plate</span> tectonics is also consistent with the observed moderate extension of only a few kilometers. These values are typical for young terrestrial rifts (e.g., the Kenya-rift) and failed arms and suggest that large scale <span class="hlt">plate</span> movement and subduction did not play a role in Martian rifting.</p> <div class="credits"> <p class="dwt_author">Grott, M.; Hauber, E.; Kronberg, P.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-08-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">156</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/49306561"> <span id="translatedtitle">Predicting and testing <span class="hlt">continental</span> vertical motion histories since the Paleozoic</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Dynamic topography at the Earth's surface caused by mantle convection can affect a range of geophysical and geological observations including bathymetry, sea-level change, <span class="hlt">continental</span> flooding, sedimentation and erosion. These observations provide important constraints on and test of mantle dynamic models. Based on global mantle convection models coupled with the surface <span class="hlt">plate</span> motion history, we compute dynamic topography and its history</p> <div class="credits"> <p class="dwt_author">Nan Zhang; Shijie Zhong; Rebecca M. Flowers</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">157</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://orgs.usd.edu/esci/exams/ocencont.html"> <span id="translatedtitle">Oceanic and <span class="hlt">Continental</span> Crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This site contains 25 questions on the topic of oceanic and <span class="hlt">continental</span> crust, which covers the physical properties and features of the two crust types. This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate verification.</p> <div class="credits"> <p class="dwt_author">Heaton, Timothy</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">158</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42053931"> <span id="translatedtitle">NSF <span class="hlt">Continental</span> Lithosphere Program</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">For several months the <span class="hlt">Continental</span> Lithosphere Program (CL) of the National Science Foundation has been subject to a major review. The process was stimulated by a series of budget setbacks over the past few years. Although Presidential budget requests have been very favorable for the Division of Earth Sciences (EAR), and there has been strong support within the National Science</p> <div class="credits"> <p class="dwt_author">Michael Mayhew; Ian MacGregor</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">159</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/56309874"> <span id="translatedtitle"><span class="hlt">Continental</span> Thermal Isostasy</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The sources of <span class="hlt">continental</span> elevations are partitioned into a combination of compositional, thermal, and geodynamic buoyancy. Because the potential elevation due to crustal compositional variations are large, an isostatic correction normalizing the effect of crustal composition on elevation is applied to reveal the effects of thermal buoyancy. Particular attention is paid to the uncertainties related to removing compositional effects. The</p> <div class="credits"> <p class="dwt_author">D. Hasterok; D. S. Chapman</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">160</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.earthbyte.org/people/dietmar/Pdf/DiCaprio_etal_Norfolk_Basin_G3_2009.pdf"> <span id="translatedtitle">Linking active margin dynamics to <span class="hlt">overriding</span> <span class="hlt">plate</span> deformation: Synthesizing geophysical images with geological data from the Norfolk Basin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The Tonga-Kermadec subduction system in the southwest Pacific preserves a series of crustal elements and sediments which have recorded subduction initiation, rift, and back-arc basin formation. The Norfolk Basin is the farthest landward of all back-arc basins formed in the Tonga-Kermadec region and may preserve the earliest record of subduction initiation regionally. For the Norfolk Basin, we use a set</p> <div class="credits"> <p class="dwt_author">Lydia DiCaprio; R. Dietmar Müller; Michael Gurnis; Alexey Goncharov</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_7");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a style="font-weight: bold;">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_9");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_8 div --> <div id="page_9" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_8");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a style="font-weight: bold;">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_10");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">161</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14905290"> <span id="translatedtitle">Geological record of fluid flow and seismogenesis along an erosive subducting <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Tectonic erosion of the <span class="hlt">overriding</span> <span class="hlt">plate</span> by the downgoing slab is believed to occur at half the Earth's subduction zones. In situ investigation of the geological processes at active erosive margins is extremely difficult owing to the deep marine environment and the net loss of forearc crust to deeper levels in the subduction zone. Until now, a fossil erosive subduction</p> <div class="credits"> <p class="dwt_author">Paola Vannucchi; Francesca Remitti; Giuseppe Bettelli</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">162</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5105325"> <span id="translatedtitle"><span class="hlt">Plate</span> motion</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The motion of tectonic <span class="hlt">plates</span> on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current <span class="hlt">plate</span> motions, diffuse <span class="hlt">plate</span> boundaries and the oceanic lithosphere, the relation between <span class="hlt">plate</span> motions and distributed deformations, accelerations and the steadiness of <span class="hlt">plate</span> motions, the distribution of current Pacific-North America motion across western North America and its margin, <span class="hlt">plate</span> reconstructions and their uncertainties, hotspots, and <span class="hlt">plate</span> dynamics. A comprehensive bibliography is provided. 126 refs.</p> <div class="credits"> <p class="dwt_author">Gordon, R.G. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">163</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUFM.T31B0477P"> <span id="translatedtitle">The Magnetic Signature of Zones of <span class="hlt">Continental</span> Collision</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Near-surface and satellite maps of the crustal component of the magnetic field can be interpreted in terms of thermal conditions at depth because the magnetic properties of rocks depend on their temperature. Observations related to <span class="hlt">continental</span> deformation at diffuse <span class="hlt">plate</span> boundaries are often considered in relation to three length scales: the thickness of the seismogenic upper crust, the entire <span class="hlt">continental</span> crust, and the mechanical lithosphere. The lower boundary of the magnetic crust coincides with the Moho, or in the presence of an elevated geotherm, with the Curie isotherm. New global perspectives on the magnetic signature of zones of <span class="hlt">continental</span> collision are afforded by the recently published Magnetic Anomaly Map of the World (Purucker, 2007, EOS, 88, 263), the MF-5 satellite magnetic field (Maus et al., 2007, Gcubed), and NASA's ST-5 constellation mission in 2006. The thickness of the magnetic crust can be estimated by integrating the MF-5 satellite magnetic field into the 3SMAC compositional and thermal model of the lithosphere, and a minimum estimate of the magnetization can be estimated using a Greens function approach. We compare our magnetic maps with the diffuse <span class="hlt">plate</span> boundary maps of Gordon (1998) and Dumoulin et al. (1998). The diffuse <span class="hlt">plate</span> boundary zones exhibit intermediate (22-31 km) magnetic thicknessses, significantly less than those of the adjacent stable <span class="hlt">plate</span>. The diffuse NE Asia <span class="hlt">plate</span> boundary zone, from the Lena River delta to the Sea of Okhotsk, is especially well- expressed in both satellite and near-surface magnetic maps.</p> <div class="credits"> <p class="dwt_author">Purucker, M. E.; Whaler, K. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">164</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/15176760"> <span id="translatedtitle">Schizophrenia, delusional symptoms, and violence: the threat/control <span class="hlt">override</span> concept reexamined.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">In 1994 Link and Stueve identified a number of symptoms--called threat/control-<span class="hlt">override</span> (TCO) symptoms--that were significantly more than others related to violence. This was confirmed by some, but not all, following studies. The contradictory results could be due to remarkable differences in sample compositions, sources used, and definitions and periods of recorded violence, but they are mainly due to problems defining the TCO symptoms. To reexamine the validity of the TCO concept from an exclusively psychopathological position, we compared in a retrospective design a sample of male offenders with schizophrenia not guilty by reason of insanity (n = 119) with a matched sample of nonoffending schizophrenia patients (n = 105). We could find no significant differences regarding the prevalence of TCO symptoms in the two groups during the course of illness. The only statistically significant discriminating factors were social origin and substance abuse. Yet, taking into account the severity of offenses, TCO symptoms emerged as being associated with severe violence. This effect is primarily attributable to the comparatively unspecific threat symptoms. Control-<span class="hlt">override</span>, to be seen as more or less typical for schizophrenia, showed no significant association with the severity of violent behavior. PMID:15176760</p> <div class="credits"> <p class="dwt_author">Stompe, Thomas; Ortwein-Swoboda, Gerhard; Schanda, Hans</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">165</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009EartD...4...21B"> <span id="translatedtitle"><span class="hlt">Plate</span> tectonics conserves angular momentum</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A new combined understanding of <span class="hlt">plate</span> tectonics, Earth internal structure, and the role of impulse in deformation of the Earth's crust is presented. <span class="hlt">Plate</span> accelerations and decelerations have been revealed by iterative filtering of the quaternion history for the Euler poles that define absolute <span class="hlt">plate</span> motion history for the past 68 million years, and provide an unprecedented precision for <span class="hlt">plate</span> angular rotation variations with time at 2-million year intervals. Stage poles represent the angular rotation of a <span class="hlt">plate</span>'s motion between adjacent Euler poles, and from which the maximum velocity vector for a <span class="hlt">plate</span> can be determined. The consistent maximum velocity variations, in turn, yield consistent estimates of <span class="hlt">plate</span> accelerations and decelerations. The fact that the Pacific <span class="hlt">plate</span> was shown to accelerate and decelerate, implied that conservation of <span class="hlt">plate</span> tectonic angular momentum must be globally conserved, and that is confirmed by the results shown here (total angular momentum ~1.4 E+27 kgm2s-1). Accordingly, if a <span class="hlt">plate</span> decelerates, other <span class="hlt">plates</span> must increase their angular momentums to compensate. In addition, the azimuth of the maximum velocity vectors yields clues as to why the "bend" in the Emperor-Hawaiian seamount trend occurred near 46 Myr. This report summarizes processing results for 12 of the 14 major tectonic <span class="hlt">plates</span> of the Earth (except for the Juan de Fuca and Philippine <span class="hlt">plates</span>). <span class="hlt">Plate</span> accelerations support the contention that <span class="hlt">plate</span> tectonics is a product of torques that most likely are sustained by the sinking of positive density anomalies due to phase changes in subducted gabbroic lithosphere at depth in the upper lower mantle (above 1200 km depth). The tectonic <span class="hlt">plates</span> are pulled along by the sinking of these positive mass anomalies, rather than moving at near constant velocity on the crests of convection cells driven by rising heat. These results imply that spreading centers are primarily passive reactive features, and fracture zones (and wedge-shaped sites of seafloor spreading) are adjustment zones that accommodate strains in the lithosphere. Further, the interlocked pattern of the Australian and Pacific <span class="hlt">plates</span> the past 42 Million years (with their absolute <span class="hlt">plate</span> motions near 90° to each other) is taken as strong evidence that large thermally driven "roller" convection cells previously inferred as the driving mechanism in earlier interpretations of <span class="hlt">continental</span> drift and <span class="hlt">plate</span> tectonics, have not been active in the Earth's mantle the past 42 Million years, if ever. This report also presents estimates of the changes in location and magnitude of the Earth's axis of total <span class="hlt">plate</span> tectonic angular momentum for the past 62 million years.</p> <div class="credits"> <p class="dwt_author">Bowin, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-03-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">166</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.geologie.ens.fr/~rooke/NCRpdf4web/Rangin&al-1999.pdf"> <span id="translatedtitle"><span class="hlt">Plate</span> convergence measured by GPS across the Sundaland\\/Philippine Sea <span class="hlt">Plate</span> deformed boundary: the Philippines and eastern Indonesia</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The western boundary of the Philippine Sea (PH) <span class="hlt">Plate</span> in the Philippines and eastern Indonesia corresponds to a wide deformation zone that includes the stretched <span class="hlt">continental</span> margin of Sundaland, the Philippine Mobile Belt (PMB), extending from Luzon to the Molucca Sea, and a mosaic of <span class="hlt">continental</span> blocks around the PH\\/Australia\\/Sunda triple junction. The GPS GEODYSSEA data are used to decipher</p> <div class="credits"> <p class="dwt_author">C. Rangin; X. Le Pichon; S. Mazzotti; M. Pubellier; N. Chamot-Rooke; M. Aurelio; Andrea Walpersdorf; R. Quebral</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">167</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/56167204"> <span id="translatedtitle"><span class="hlt">Continental</span> margin drilling program</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The initial responses from OMB, Congress, and industry have been overwhelmingly positive in support of a proposed major drilling program along the U.S. offshore coastal areas in deep water.The extensive sedimentary deposits located along the U.S. <span class="hlt">continental</span> slopes are, as yet, unexplored. There have been numerous suggestions that there is a significant potential for extensive reserves of hydrocarbons, but these</p> <div class="credits"> <p class="dwt_author">Peter M. Bell</p> <p class="dwt_publisher"></p> <p class="publishDate">1980-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">168</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55034387"> <span id="translatedtitle">Paleomagnetic Quantification of Neogene Block Rotations within an Active Transtensional <span class="hlt">Plate</span> Boundary, Baja California, Mexico</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Compared to oceanic <span class="hlt">plate</span> boundaries which are generally narrow zones of deformation, <span class="hlt">continental</span> <span class="hlt">plate</span> boundaries appear as widespread areas with complex and poorly understood kinematics. Motion of crustal blocks within these ``diffuse <span class="hlt">plate</span> boundaries'' causes rather small-scale lithospheric deformation within the boundary zone, while the main <span class="hlt">plates</span> behave more rigid. Complex deformation patterns of interacting terranes separated by a variety</p> <div class="credits"> <p class="dwt_author">J. Weber; P. J. Umhoefer; J. A. Pérez Venzor; V. Bachtadse</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">169</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012SolE....3..387B"> <span id="translatedtitle">Insight into collision zone dynamics from topography: numerical modelling results and observations</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Dynamic models of subduction and <span class="hlt">continental</span> collision are used to predict dynamic topography changes on the <span class="hlt">overriding</span> <span class="hlt">plate</span>. The modelling results show a distinct evolution of topography on the <span class="hlt">overriding</span> <span class="hlt">plate</span>, during subduction, <span class="hlt">continental</span> collision and slab break-off. A prominent topographic feature is a temporary (few Myrs) basin on the <span class="hlt">overriding</span> <span class="hlt">plate</span> after initial collision. This "collisional mantle dynamic basin" (CMDB) is caused by slab steepening drawing, material away from the base of the <span class="hlt">overriding</span> <span class="hlt">plate</span>. Also, during this initial collision phase, surface uplift is predicted on the <span class="hlt">overriding</span> <span class="hlt">plate</span> between the suture zone and the CMDB, due to the subduction of buoyant <span class="hlt">continental</span> material and its isostatic compensation. After slab detachment, redistribution of stresses and underplating of the <span class="hlt">overriding</span> <span class="hlt">plate</span> cause the uplift to spread further into the <span class="hlt">overriding</span> <span class="hlt">plate</span>. This topographic evolution fits the stratigraphy found on the <span class="hlt">overriding</span> <span class="hlt">plate</span> of the Arabia-Eurasia collision zone in Iran and south east Turkey. The sedimentary record from the <span class="hlt">overriding</span> <span class="hlt">plate</span> contains Upper Oligocene-Lower Miocene marine carbonates deposited between terrestrial clastic sedimentary rocks, in units such as the Qom Formation and its lateral equivalents. This stratigraphy shows that during the Late Oligocene-Early Miocene the surface of the <span class="hlt">overriding</span> <span class="hlt">plate</span> sank below sea level before rising back above sea level, without major compressional deformation recorded in the same area. Our modelled topography changes fit well with this observed uplift and subsidence.</p> <div class="credits"> <p class="dwt_author">Bottrill, A. D.; van Hunen, J.; Allen, M. B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-11-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">170</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.scec.org/education/k12/learn/plate4.htm"> <span id="translatedtitle"><span class="hlt">Plate</span> Boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This site provides information on <span class="hlt">plate</span> boundaries, which are found at the edge of the lithospheric <span class="hlt">plates</span> and are of three types: convergent, divergent and conservative. Wide zones of deformation are usually characteristic of <span class="hlt">plate</span> boundaries because of the interaction between two <span class="hlt">plates</span>. The three boundaries are characterized by their distinct motions which are described in the text and depicted with block diagram illustrations, all of which are animated. There are also two maps that show the direction of motion of the <span class="hlt">plates</span>. Active links lead to more information on <span class="hlt">plate</span> tectonics.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">171</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51684308"> <span id="translatedtitle">Lower Crustal Earthquakes Near a <span class="hlt">Continental</span> Rift - a Soggy Jelly Sandwich Works in New Zealand</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Subduction of the Pacific <span class="hlt">plate</span> beneath the North Island of New Zealand is accompanied by active back-arc spreading within <span class="hlt">continental</span> crust in the Taupo Volcanic Zone (TVZ). This spreading terminates in the central North Island at the latitude of the andesitic Mt Ruapehu. Southwest of this termination, there is an unusual concentration of lower crustal seismicity in the overlying <span class="hlt">plate</span>,</p> <div class="credits"> <p class="dwt_author">M. Reyners; D. Eberhart-Phillips; G. Stuart</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">172</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48923413"> <span id="translatedtitle">Observations at convergent margins concerning sediment subduction, subduction erosion, and the growth of <span class="hlt">continental</span> crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">At ocean margins where two <span class="hlt">plates</span> converge, the oceanic <span class="hlt">plate</span> sinks or is subducted beneath an upper one topped by a layer of terrestrial crust. This crust is constructed of <span class="hlt">continental</span> or island arc material. The subduction process either builds juvenile masses of terrestrial crust through arc volcanism or new areas of crust through the piling up of accretionary masses</p> <div class="credits"> <p class="dwt_author">Roland von Huene; David W. Scholl</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">173</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010PhDT........51H"> <span id="translatedtitle">Thermal state of <span class="hlt">continental</span> and oceanic lithosphere</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The thermal state of the <span class="hlt">continental</span> and oceanic lithosphere is reassessed on the basis of new databases for global heat flow and lithospheric heat production, recent advances in thermophysical properties measurements of minerals at high pressures and temperatures, and a better understanding of convective heat loss in young seafloor. The updated global heat flow database incorporates >60,000 records with >44,800 heat flow determinations. The update significantly increases the quantity and spatial coverage of global heat flow data since the last update in 1993. A new family of <span class="hlt">continental</span> geotherms is proposed that is parametric in surface heat flow and takes advantage of thermophysical property data. The range of geotherms is constrained by xenolith P--T estimates; a cratonic geotherm consistent with a surface heat flow of 40 mW/m2 is particularly well constrained. Upper crustal heat production represents ˜26% of the total surface heat flow. Average heat production for the <span class="hlt">continental</span> lower crust and mantle are 0.4 muW/m3 and 0.02 muW/m3, respectively. Recent controversy about the interpretation of heat flow observations in young seafloor is resolved by careful filtering of data based on sediment thickness and distance from seamounts and weighting marine studies where the environment of heat flow measurements is carefully documented. Oceanic geotherms, fit to bathymetry and heat flow data, are produced for a <span class="hlt">plate</span> model with 7 km thick crust, a <span class="hlt">plate</span> thickness of 95 km, and mantle potential temperature of 1425°C. While the current estimate of global heat loss (44 TW) is reasonable, these new reference models will be instrumental in refining and estimating uncertainty in the solid Earth's global heat loss.</p> <div class="credits"> <p class="dwt_author">Hasterok, Derrick P.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">174</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.vims.edu/bridge/archive0902.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">In this activity students use data from underwater earthquakes to outline the location of <span class="hlt">plate</span> boundaries. Data from the Northeast Pacific, eastern Equatorial Pacific, and North Atlantic are examined in more detail. Background information on <span class="hlt">plate</span> tectonics is provided.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">175</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.T42C..08M"> <span id="translatedtitle"><span class="hlt">Plate</span> Coupling and Strain Partitioning in the Northeastern Caribbean</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Major strike-slip faults commonly found on the margin of <span class="hlt">overriding</span> <span class="hlt">plates</span> in oblique subduction zone settings facilitate the partitioning of strain into trench-parallel and trench-normal tectonics. Their development has been proposed to be controlled by factors such as convergence obliquity, basal tractions, magnitude of slab-pull force, or strength of interplate coupling. In the northeastern Caribbean, the direction of GPS velocities and earthquake slip vectors suggests low coupling along the Puerto Rico and Lesser Antilles trenches, but strong coupling to the west along the Hispaniola margin, while the convergence obliquity remains constant. Coincidentally, large strike-slip faults in the <span class="hlt">overriding</span> <span class="hlt">plate</span> only develop in Hispaniola, which is also the locus of the largest historical subduction earthquakes in the Caribbean (M8.0, 1946-53 sequence). We investigate interplate coupling at the Caribbean-North American <span class="hlt">plate</span> boundary using a model that allows for block rotations and elastic strain accumulation on partially coupled faults. Model parameters (block rotations and coupling on interplate faults) are derived from an inversion of earthquake slip vectors and new GPS data covering Haiti, the Dominican Republic, Puerto Rico and the Virgin Islands, and the Lesser Antilles. We find that intraplate coupling is high in the western half of the domain, coincident with the development of large and fast-slipping strike-slip faults in the upper <span class="hlt">plate</span> that partition the Carribean/North America <span class="hlt">plate</span> motion, but low in its eastern half, along the Puerto Rico and Lesser Antilles subductions, that show little to no strain partitioning. This suggests that strain partitioning occur only if interplate coupling is large enough to effectively transfer shear stresses to the <span class="hlt">overriding</span> <span class="hlt">plate</span>.</p> <div class="credits"> <p class="dwt_author">Manaker, D.; Calais, E.; Jansma, P.; Mattioli, G.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">176</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.uky.edu/AS/Geology/howell/goodies/elearning/module04swf.swf"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This interactive Flash explores <span class="hlt">plate</span> tectonics and provides an interactive map where users can identify <span class="hlt">plate</span> boundaries with name and velocities as well as locations of earthquakes, volcanoes, and hotspots. The site also provides animations and supplementary information about <span class="hlt">plate</span> movement and subduction. This resource is a helpful overview or review for introductory level high school or undergraduate physical geology or Earth science students.</p> <div class="credits"> <p class="dwt_author">Smoothstone; Company, Houghton M.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">177</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://ia.usu.edu/viewproject.php?project=ia:15692"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Create a poster all about <span class="hlt">Plate</span> Tectonics! Directions: Make a poster about <span class="hlt">Plate</span> Tectonics. (20 points) Include at least (1) large picture (15 points) on your poster complete with labels of every part (10 points). (15 points) Include at least three (3) facts about <span class="hlt">Plate</span> Tectonics. (5 points ...</p> <div class="credits"> <p class="dwt_author">Walls, Mrs.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-30</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">178</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=N8830254"> <span id="translatedtitle">Effect of Thicker Oceanic Crust in the Archaean on the Growth of <span class="hlt">Continental</span> Crust through Time (Abstract Only).</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">Present crustal evolution models fail to account for the generation of the large volume of <span class="hlt">continental</span> crust in the required time intervals. All Archaean <span class="hlt">plate</span> tectonic models, whether invoking faster spreading rates, similar to today's spreading rates, o...</p> <div class="credits"> <p class="dwt_author">M. E. Wilks</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">179</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008Tecto..27.4007C"> <span id="translatedtitle"><span class="hlt">Plate</span> subrotations</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The kinematics of <span class="hlt">plates</span> is defined by Euler pole and angular velocity. However, during their journey, <span class="hlt">plates</span> may be affected by additional simultaneous rotations (i.e., subrotations) while they are rotating about their Euler poles. The kinematic description of this particular <span class="hlt">plate</span> motion requires a different analytical approach: two angular velocities and two poles are necessary to completely describe <span class="hlt">plate</span> displacements. If a subrotation occurs, none of the points on a <span class="hlt">plate</span> moves along circles of the Euler pole but, instead, follows cycloid trajectories because of the combination of the two simultaneous rotations. Regardless of the forces that move the lithosphere, every time a <span class="hlt">plate</span> experiences a subrotation, an additional force (or resisting) force could act on the <span class="hlt">plate</span>, generating the two-rotation motion. In the hot spot reference frame, we applied this model to the North America <span class="hlt">plate</span>, investigating its past motion for a time interval ?t = 43 Ma up to the present and comparing results with those obtained by Gordon and Jurdy (1986). This application shows how the different positions of the North America <span class="hlt">plate</span> over most of the Cenozoic can be reconstructed by two-rotation <span class="hlt">plate</span> kinematics.</p> <div class="credits"> <p class="dwt_author">Cuffaro, Marco; Caputo, Michele; Doglioni, Carlo</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-08-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">180</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55041174"> <span id="translatedtitle">Topographic form of the Coast Ranges of the Cascadia Margin in relation ot coastal uplift rates and <span class="hlt">plate</span> subduction</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The Coast Ranges of the Cascadia margin are <span class="hlt">overriding</span> the subducted Juan de Fuca\\/Gorda <span class="hlt">plate</span>. We investigate the extent to which the latitudinal change in attributes related to the subduction process. These attributes include the varibale age of the subducted slab that underlies the Coast Ranges and average vertical crustal velocities of the western margin of the Coast Rnages for</p> <div class="credits"> <p class="dwt_author">Harvey M. Kelsey; David C. Engebretson; Clifton E. Mitchell; Robert L. Ticknor</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_8");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a style="font-weight: bold;">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_10");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_9 div --> <div id="page_10" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_9");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a style="font-weight: bold;">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_11");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">181</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/13560086"> <span id="translatedtitle">Visual Abilities and Misconceptions About <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Diagrams, drawings, and pictures are prototypical representations of concepts. Students' drawings of their concepts of convergent <span class="hlt">plate</span> boundaries provided an efficient means of discovering some widely held misconceptions. Over 600 general education students' drawings of continent -continent convergent boundaries reveal two common misconceptions. Approximately one-third drew a continent-continent convergent boundary with concave slabs of <span class="hlt">continental</span> crust as one might imagine</p> <div class="credits"> <p class="dwt_author">Duncan F. Sibley</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">182</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.9469D"> <span id="translatedtitle">Slab eduction following <span class="hlt">continental</span> subduction and slab detachment</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The geodynamic process of slab eduction characterizes the normal-sense extraction of previously subducted <span class="hlt">continental</span> <span class="hlt">plate</span>. Eduction leads to a coherent motion of the <span class="hlt">continental</span> lithosphere and can partly accommodate the exhumation of high pressure domains. This motion is driven by the buoyancy of subducted crust, it may take place after slab detachment and the loss of slab pull. In order to test the eduction model, we employ two-dimensional thermo-mechanical modeling. Our results indicate that eduction triggers adiabatic decompression of the subducted crust (~2 GPa) in a narrow timespan (~5 Ma). As the slab is educted, large strain takes place in the former subduction channel and topography builds up with ongoing extension. To further quantify the parameters involved into eduction, we compare parametric tests to analytic <span class="hlt">plate</span> velocity estimations. We could show that eduction is a viable mechanism under a reasonable range of mantle viscosity, subduction channel viscosity and orogenic root buoyancy.</p> <div class="credits"> <p class="dwt_author">Duretz, Thibault; Gerya, Taras V.; Andersen, Torgeir B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">183</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/intro/activities/25297.html"> <span id="translatedtitle">Identifying <span class="hlt">Plate</span> Tectonic Boundaries for a Virtual Ocean Basin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Students observe a virtual ocean basin and two adjacent <span class="hlt">continental</span> margins. From the characteristics of the sea floor and adjacent land, students infer where <span class="hlt">plate</span> boundaries might be present. They then predict where earthquakes and volcanoes might occur. Finally, they draw their inferred <span class="hlt">plate</span> boundaries in cross section.</p> <div class="credits"> <p class="dwt_author">Reynolds, Stephen</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">184</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/44474538"> <span id="translatedtitle">Estimation of <span class="hlt">continental</span> precipitation recycling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The total amount of water that precipitates on large <span class="hlt">continental</span> regions is supplied by two mechanisms: (1) advection from the surrounding areas external to the region and (2) evaporation and transpiration from the land surface within the region. The latter supply mechanism is tantamount to the recycling of precipitation over the <span class="hlt">Continental</span> area. The degree to which regional precipitation is</p> <div class="credits"> <p class="dwt_author">Kaye L. Brubaker; Dara Entekhabi; P. S. Eagleson</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">185</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52271326"> <span id="translatedtitle">Diffuse Oceanic <span class="hlt">Plate</span> Boundaries, Thin Viscous Sheets of Oceanic Lithosphere, and Late Miocene Changes in <span class="hlt">Plate</span> Motion and Tectonic Regime</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Diffuse <span class="hlt">plate</span> boundaries are often viewed as a characteristic only of <span class="hlt">continental</span> lithosphere and as a consequence of its rheology, while narrow boundaries and <span class="hlt">plate</span> rigidity are viewed as characteristic of oceanic lithosphere. Here we review some of the evidence that shows that deformation in the ocean basins is in many places just as diffuse as deformation in the continents.</p> <div class="credits"> <p class="dwt_author">R. G. Gordon; J. Royer</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">186</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1988EOSTr..69.1604M"> <span id="translatedtitle">NSF <span class="hlt">Continental</span> Lithosphere Program</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">For several months the <span class="hlt">Continental</span> Lithosphere Program (CL) of the National Science Foundation has been subject to a major review. The process was stimulated by a series of budget setbacks over the past few years. Although Presidential budget requests have been very favorable for the Division of Earth Sciences (EAR), and there has been strong support within the National Science Foundation and Congress, actual appropriations by Congress have been disappointing.In each year the final allocation to EAR has been affected by external factors beyond the control of the Foundation. In the four fiscal years from 1986 through 1989 the factors include reductions tied to the Gramm-Rudman deficit reduction measures, congressional reaction to the October 1987 stock market crash, and two years of protection for the Ocean Sciences part of the NSF budget that was paid for from the budgets of the Atmospheric and Earth Sciences divisions.</p> <div class="credits"> <p class="dwt_author">Mayhew, Michael; MacGregor, Ian</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">187</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2008GeoJI.174..889M"> <span id="translatedtitle">Interseismic <span class="hlt">Plate</span> coupling and strain partitioning in the Northeastern Caribbean</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The northeastern Caribbean provides a natural laboratory to investigate strain partitioning, its causes and its consequences on the stress regime and tectonic evolution of a subduction <span class="hlt">plate</span> boundary. Here, we use GPS and earthquake slip vector data to produce a present-day kinematic model that accounts for secular block rotation and elastic strain accumulation, with variable interplate coupling, on active faults. We confirm that the oblique convergence between Caribbean and North America in Hispaniola is partitioned between <span class="hlt">plate</span> boundary parallel motion on the Septentrional and Enriquillo faults in the <span class="hlt">overriding</span> <span class="hlt">plate</span> and <span class="hlt">plate</span>-boundary normal motion at the <span class="hlt">plate</span> interface on the Northern Hispaniola Fault. To the east, the Caribbean/North America <span class="hlt">plate</span> motion is accommodated by oblique slip on the faults bounding the Puerto Rico block to the north (Puerto Rico subduction) and to the south (Muertos thrust), with no evidence for partitioning. The spatial correlation between interplate coupling, strain partitioning and the subduction of buoyant oceanic asperities suggests that the latter enhance the transfer of interplate shear stresses to the <span class="hlt">overriding</span> <span class="hlt">plate</span>, facilitating strike-slip faulting in the <span class="hlt">overriding</span> <span class="hlt">plate</span>. The model slip rate deficit, together with the dates of large historical earthquakes, indicates the potential for a large (Mw7.5 or greater) earthquake on the Septentrional fault in the Dominican Republic. Similarly, the Enriquillo fault in Haiti is currently capable of a Mw7.2 earthquake if the entire elastic strain accumulated since the last major earthquake was released in a single event today. The model results show that the Puerto Rico/Lesser Antilles subduction thrust is only partially coupled, meaning that the <span class="hlt">plate</span> interface is accumulating elastic strain at rates slower than the total <span class="hlt">plate</span> motion. This does not preclude the existence of isolated locked patches accumulating elastic strain to be released in future earthquakes, but whose location and geometry are not resolvable with the present data distribution. Slip deficit on faults from this study are used in a companion paper to calculate interseismic stress loading and, together with stress changes due to historical earthquakes, derive the recent stress evolution in the NE Caribbean.</p> <div class="credits"> <p class="dwt_author">Manaker, D. M.; Calais, E.; Freed, A. M.; Ali, S. T.; Przybylski, P.; Mattioli, G.; Jansma, P.; Prépetit, C.; de Chabalier, J. B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-09-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">188</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/46490095"> <span id="translatedtitle">Alfred Wegener—From <span class="hlt">continental</span> drift to <span class="hlt">plate</span> tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">What is the nature of the force or mechanism that moves massive continents thousands of miles across? What causes violent\\u000a earthquakes to displace huge landmasses abruptly? How could great mountain ranges like Himalayas and Alps rise to such incredible\\u000a heights? What makes earth's interior so restless? Answers to some of these questions may lie in understanding the Earth's\\u000a interior itself.</p> <div class="credits"> <p class="dwt_author">A F Saigeetha; Ravinder Kumar Banyal</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">189</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://orgs.usd.edu/esci/exams/tectonics.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This site contains 25 questions on the topic of <span class="hlt">plate</span> tectonics, which covers the development of the theory, crustal movements, geologic features associated with tectonics, and <span class="hlt">plate</span> boundaries (convergent, divergent, transform). This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate verification.</p> <div class="credits"> <p class="dwt_author">Heaton, Timothy</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">190</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.6720K"> <span id="translatedtitle">Magmatism and deformation during <span class="hlt">continental</span> breakup</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The rifting of continents and the transition to seafloor spreading is characterised by extensional faulting and thinning of the lithosphere, and is sometimes accompanied by voluminous intrusive and extrusive magmatism. In order to understand how these processes develop over time to break continents apart, we have traditionally relied on interpreting the geological record at the numerous fully developed, ancient rifted margins around the world. In these settings, however, it is difficult to discriminate between different mechanisms of extension and magmatism because the continent-ocean transition is typically buried beneath thick layers of volcanic and sedimentary rocks, and the tectonic and volcanic activity that characterised breakup has long-since ceased. Ongoing <span class="hlt">continental</span> breakup in the African and Arabian rift systems offers a unique opportunity to address these problems because it exposes several sectors of tectonically active rift sector development spanning the transition from embryonic <span class="hlt">continental</span> rifting in the south to incipient seafloor spreading in the north. Here I synthesise exciting, multidisciplinary observational and modelling studies using geophysical, geodetic, petrological and numerical techniques that uniquely constrain the distribution, time-scales, and interactions between extension and magmatism during the progressive breakup of the African <span class="hlt">Plate</span>. This new research has identified the previously unrecognised role of rapid and episodic dike emplacement in accommodating a large proportion of extension during <span class="hlt">continental</span> rifting. We are now beginning to realise that changes in the dominant mechanism for strain over time (faulting, stretching and magma intrusion) impact dramatically on magmatism and rift morphology. The challenge now is to take what we're learned from East Africa and apply it to the rifted margins whose geological record documents breakup during entire Wilson Cycles.</p> <div class="credits"> <p class="dwt_author">Keir, Derek</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">191</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012SolED...4..889B"> <span id="translatedtitle">Insight into collision zone dynamics from topography: numerical modelling results and observations</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Dynamic models of subduction and <span class="hlt">continental</span> collision are used to predict dynamic topography changes on the <span class="hlt">overriding</span> <span class="hlt">plate</span>. The modelling results show a distinct evolution of topography on the <span class="hlt">overriding</span> <span class="hlt">plate</span>, during subduction, <span class="hlt">continental</span> collision and slab break-off. A prominent topographic feature is a temporary (few Myrs) deepening in the area of the back arc-basin after initial collision. This collisional mantle dynamic basin (CMDB) is caused by slab steepening drawing material away from the base of the <span class="hlt">overriding</span> <span class="hlt">plate</span>. Also during this initial collision phase, surface uplift is predicted on the <span class="hlt">overriding</span> <span class="hlt">plate</span> between the suture zone and the CMDB, due to the subduction of buoyant <span class="hlt">continental</span> material and its isostatic compensation. After slab detachment, redistribution of stresses and underplating of the <span class="hlt">overriding</span> <span class="hlt">plate</span> causes the uplift to spread further into the <span class="hlt">overriding</span> <span class="hlt">plate</span>. This topographic evolution fits the stratigraphy found on the <span class="hlt">overriding</span> <span class="hlt">plate</span> of the Arabia-Eurasia collision zone in Iran and south east Turkey. The sedimentary record from the <span class="hlt">overriding</span> <span class="hlt">plate</span> contains Upper Oligocene-Lower Miocene marine carbonates deposited between terrestrial clastic sedimentary rocks, in units such as the Qom Formation and its lateral equivalents. This stratigraphy shows that during the Late Oligocene-Early Miocene the surface of the <span class="hlt">overriding</span> <span class="hlt">plate</span> sank below sea level before rising back above sea level, without major compressional deformation recorded in the same area. This uplift and subsidence pattern correlates well with our modelled topography changes.</p> <div class="credits"> <p class="dwt_author">Bottrill, A. D.; van Hunen, J.; Allen, M. B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-07-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">192</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18174440"> <span id="translatedtitle">Intermittent <span class="hlt">plate</span> tectonics?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Although it is commonly assumed that subduction has operated continuously on Earth without interruption, subduction zones are routinely terminated by ocean closure and supercontinent assembly. Under certain circumstances, this could lead to a dramatic loss of subduction, globally. Closure of a Pacific-type basin, for example, would eliminate most subduction, unless this loss were compensated for by comparable subduction initiation elsewhere. Given the evidence for Pacific-type closure in Earth's past, the absence of a direct mechanism for termination/initiation compensation, and recent data supporting a minimum in subduction flux in the Mesoproterozoic, we hypothesize that dramatic reductions or temporary cessations of subduction have occurred in Earth's history. Such deviations in the continuity of <span class="hlt">plate</span> tectonics have important consequences for Earth's thermal and <span class="hlt">continental</span> evolution. PMID:18174440</p> <div class="credits"> <p class="dwt_author">Silver, Paul G; Behn, Mark D</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">193</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/21452048"> <span id="translatedtitle">Three-dimensional spatial cognition: information in the vertical dimension <span class="hlt">overrides</span> information from the horizontal.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Fish live in three-dimensional environments, through which they swim with three translational and three rotational degrees of freedom. Navigating through such environments is recognised as a difficult problem, yet fish, and other animals that swim and fly, achieve this regularly. Despite this, the vast majority of research has considered how animals navigate horizontally from place to place and has ignored the vertical component. Here, we test the importance of the vertical axis of space for fish solving a three-dimensional spatial cognition task. We trained banded tetras (Astyanax fasciatus) to learn the route towards a goal in a rotating Y-maze in which the arms led either up and left or down and right in an environment that allowed access to visual landmarks providing horizontal and vertical information. Our results revealed that the landmarks increased navigational efficiency during training. However, these landmarks were ignored when the horizontal and vertical components were placed in conflict with each other by rotating the maze 90° during testing. From this surprising result, we conclude that the cues that are present in the vertical axis (presumably hydrostatic pressure) <span class="hlt">override</span> landmark cues that have been shown to be salient in experiments that only consider the horizontal component of space. PMID:21452048</p> <div class="credits"> <p class="dwt_author">Holbrook, Robert I; Burt de Perera, Theresa</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-03-31</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">194</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3571333"> <span id="translatedtitle">More than Motility: Salmonella Flagella Contribute to <span class="hlt">Overriding</span> Friction and Facilitating Colony Hydration during Swarming</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">We show in this study that Salmonella cells, which do not upregulate flagellar gene expression during swarming, also do not increase flagellar numbers per ?m of cell length as determined by systematic counting of both flagellar filaments and hooks. Instead, doubling of the average length of a swarmer cell by suppression of cell division effectively doubles the number of flagella per cell. The highest agar concentration at which Salmonella cells swarmed increased from the normal 0.5% to 1%, either when flagella were overproduced or when expression of the FliL protein was enhanced in conjunction with stator proteins MotAB. We surmise that bacteria use the resulting increase in motor power to overcome the higher friction associated with harder agar. Higher flagellar numbers also suppress the swarming defect of mutants with changes in the chemotaxis pathway that were previously shown to be defective in hydrating their colonies. Here we show that the swarming defect of these mutants can also be suppressed by application of osmolytes to the surface of swarm agar. The “dry” colony morphology displayed by che mutants was also observed with other mutants that do not actively rotate their flagella. The flagellum/motor thus participates in two functions critical for swarming, enabling hydration and <span class="hlt">overriding</span> surface friction. We consider some ideas for how the flagellum might help attract water to the agar surface, where there is no free water.</p> <div class="credits"> <p class="dwt_author">Partridge, Jonathan D.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">195</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/23264575"> <span id="translatedtitle">More than motility: Salmonella flagella contribute to <span class="hlt">overriding</span> friction and facilitating colony hydration during swarming.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">We show in this study that Salmonella cells, which do not upregulate flagellar gene expression during swarming, also do not increase flagellar numbers per ?m of cell length as determined by systematic counting of both flagellar filaments and hooks. Instead, doubling of the average length of a swarmer cell by suppression of cell division effectively doubles the number of flagella per cell. The highest agar concentration at which Salmonella cells swarmed increased from the normal 0.5% to 1%, either when flagella were overproduced or when expression of the FliL protein was enhanced in conjunction with stator proteins MotAB. We surmise that bacteria use the resulting increase in motor power to overcome the higher friction associated with harder agar. Higher flagellar numbers also suppress the swarming defect of mutants with changes in the chemotaxis pathway that were previously shown to be defective in hydrating their colonies. Here we show that the swarming defect of these mutants can also be suppressed by application of osmolytes to the surface of swarm agar. The "dry" colony morphology displayed by che mutants was also observed with other mutants that do not actively rotate their flagella. The flagellum/motor thus participates in two functions critical for swarming, enabling hydration and <span class="hlt">overriding</span> surface friction. We consider some ideas for how the flagellum might help attract water to the agar surface, where there is no free water. PMID:23264575</p> <div class="credits"> <p class="dwt_author">Partridge, Jonathan D; Harshey, Rasika M</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-12-21</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">196</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3084701"> <span id="translatedtitle">Nicotine <span class="hlt">Overrides</span> DNA Damage-Induced G1/S Restriction in Lung Cells</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">As an addictive substance, nicotine has been suggested to facilitate pro-survival activities (such as anchorage-independent growth or angiogenesis) and the establishment of drug resistance to anticancer therapy. Tobacco smoking consists of a variety of carcinogens [such as benzopyrene (BP) and nitrosamine derivatives] that are able to cause DNA double strand breaks. However, the effect of nicotine on DNA damage-induced checkpoint response induced by genotoxins remains unknown. In this study, we investigated the events occurred during G1 arrest induced by ?-radiation or BP in nicotine-treated murine or human lung epithelial cells. DNA synthesis was rapidly inhibited after exposure to ?-radiation or BP treatment, accompanied with the activation of DNA damage checkpoint. When these cells were co-treated with nicotine, the growth restriction was compromised, manifested by upregulation of cyclin D and A, and attenuation of Chk2 phosphorylation. Knockdown of cyclin D or Chk2 by the siRNAs blocked nicotine-mediated effect on DNA damage checkpoint activation. However, nicotine treatment appeared to play no role in nocodazole-induced mitotic checkpoint activation. Overall, our study presented a novel observation, in which nicotine is able to <span class="hlt">override</span> DNA damage checkpoint activated by tobacco-related carcinogen BP or ?-irradiation. The results not only indicates the potentially important role of nicotine in facilitating the establishment of genetic instability to promote lung tumorigenesis, but also warrants a dismal prognosis for cancer patients who are smokers, heavily exposed second-hand smokers or nicotine users.</p> <div class="credits"> <p class="dwt_author">Zhu, Tongbo; Guo, Jinjin; Kim, Sung-Hoon; Chen, Chang Yan</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">197</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17609189"> <span id="translatedtitle">Fuelling decisions in migratory birds: geomagnetic cues <span class="hlt">override</span> the seasonal effect.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Recent evaluations of both temporal and spatial precision in bird migration have called for external cues in addition to the inherited programme defining the migratory journey in terms of direction, distance and fuelling behaviour along the route. We used juvenile European robins (Erithacus rubecula) to study whether geomagnetic cues affect fuel deposition in a medium-distance migrant by simulating a migratory journey from southeast Sweden to the wintering area in southern Spain. In the late phase of the onset of autumn migration, robins exposed to the magnetic treatment attained a lower fuel load than control birds exposed to the ambient magnetic field of southeast Sweden. In contrast, robins captured in the early phase of the onset of autumn migration all showed low fuel deposition irrespective of experimental treatment. These results are, as expected, the inverse of what we have found in similar studies in a long-distance migrant, the thrush nightingale (Luscinia luscinia), indicating that the reaction in terms of fuelling behaviour to a simulated southward migration varies depending on the relevance for the species. Furthermore, we suggest that information from the geomagnetic field act as an important external cue <span class="hlt">overriding</span> the seasonal effect on fuelling behaviour in migratory birds. PMID:17609189</p> <div class="credits"> <p class="dwt_author">Kullberg, Cecilia; Henshaw, Ian; Jakobsson, Sven; Johansson, Patrik; Fransson, Thord</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-09-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">198</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/19034499"> <span id="translatedtitle">Precueing imminent conflict does not <span class="hlt">override</span> sequence-dependent interference adaptation.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Interference effects are largely reduced after cognitive conflicts in previous trials. This sequence-dependent interference adaptation is often seen as a consequence of strategic executive control. We sought to investigate whether sequential modulations are comparable with cue-induced strategic adjustments in spatial interference tasks. If so, reliable cues indicating the next compatibility condition should <span class="hlt">override</span> effects caused by prior events. To this end, cues were introduced in a spatial stimulus-response compatibility task and a Simon task that either indicated the upcoming trial compatibility (rule cues) or the target position, which was not related to the S-R rule (position cues). The proportion of valid cues was either completely or predominantly valid. In both tasks cueing benefits for absolutely reliable rule cues were clearly present. Remarkably, sequential modulations were not influenced by effective rule cueing and vice versa. Even absolutely reliable information about prospective control demands did not cancel out sequence-dependent interference adaptation. In addition, the contingent negative variation-an event-related brain potential in the cue-target interval that is related to response preparation and readiness-showed additive effects of preceding compatibility and cue reliability. The present results indicate that processes underlying sequence-dependent interference adaptation differ from cue-induced strategic processes of cognitive control. PMID:19034499</p> <div class="credits"> <p class="dwt_author">Alpay, Gamze; Goerke, Monique; Stürmer, Birgit</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-11-26</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">199</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T21D..06E"> <span id="translatedtitle">Factors controlling depth of <span class="hlt">continental</span> rifts</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Rifting is a fundamental <span class="hlt">plate</span> tectonic process, which forms elongated, narrow tectonic depressions in the Earth's surface and, eventually, may break <span class="hlt">continental</span> <span class="hlt">plates</span> to form new oceanic lithosphere. Subsidence of rift basins is caused by thinning of the crust and lithospheric mantle together with isostatic compensation for the extra load of sediments and thermal relaxation. It is generally believed that the final depth of rift basins is primarily controlled by the amount of stretching and that other processes only have secondary influence. However, we show that the relative rheological strength of faults inside and outside rift zones exerts substantial control on the volume of the final rift basin (by more than a factor of 3) even for the same amount of extension (total or inside the rift zone). This surprising result is mainly caused by irreversible deepening of the rift graben during stretching due to lower crustal flow when the faults in the rift zone are weak, whereas the effect is negligible for strong faults. Relatively strong faults inside the rift zone lead to substantial stretching of adjacent crust, and we find that long term stretching outside the main rift zone may explain the formation of wide <span class="hlt">continental</span> margins, which are now below sea level. We also demonstrate that fast syn-rift erosion/sedimentation rates can increase the final volume of rift basins by up to a factor of 1.7 for weak crustal faults, whereas this effect is insignificant for strong faults inside the rift zone. These findings have significant implications for estimation of stretching factors, tectonic forces, and geodynamic evolution of sedimentary basins around failed rift zones.</p> <div class="credits"> <p class="dwt_author">Elesin, Y.; Artemieva, I. M.; Thybo, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">200</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5571408"> <span id="translatedtitle">Palaeomagnetism and the <span class="hlt">continental</span> crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">This book is an introduction to palaeomagnetism offering treatment of theory and practice. It analyzes the palaeomagnetic record over the whole of geological time, from the Archaean to the Cenozoic, and goes on to examine the impact of past geometries and movements of the <span class="hlt">continental</span> crust at each geological stage. Topics covered include theory of rock and mineral magnetism, field and laboratory methods, growth and consolidation of the <span class="hlt">continental</span> crust in Archaean and Proterozoic times, Palaeozoic palaeomagnetism and the formation of Pangaea, the geomagnetic fields, <span class="hlt">continental</span> movements, configurations and mantle convection.</p> <div class="credits"> <p class="dwt_author">Piper, J.D.A.</p> <p class="dwt_publisher"></p> <p class="publishDate">1987-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_9");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a style="font-weight: bold;">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_11");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_10 div --> <div id="page_11" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_10");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a style="font-weight: bold;">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_12");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">201</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5920133"> <span id="translatedtitle"><span class="hlt">Plate</span> motion and deformation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Our goal is to understand the motions of the <span class="hlt">plates</span>, the deformation along their boundaries and within their interiors, and the processes that control these tectonic phenomena. In the broadest terms, we must strive to understand the relationships of regional and local deformation to flow in the upper mantle and the rheological, thermal and density structure of the lithosphere. The essential data sets which we require to reach our goal consist of maps of current strain rates at the earth's surface and the distribution of integrated deformation through time as recorded in the geologic record. Our success will depend on the effective synthesis of crustal kinematics with a variety of other geological and geophysical data, within a quantitative theoretical framework describing processes in the earth's interior. Only in this way can we relate the snapshot of current motions and earth structure provided by geodetic and geophysical data with long-term processes operating on the time scales relevant to most geological processes. The wide-spread use of space-based techniques, coupled with traditional geological and geophysical data, promises a revolution in our understanding of the kinematics and dynamics of <span class="hlt">plate</span> motions over a broad range of spatial and temporal scales and in a variety of geologic settings. The space-based techniques that best address problems in <span class="hlt">plate</span> motion and deformation are precise space-geodetic positioning -- on land and on the seafloor -- and satellite acquisition of detailed altimetric and remote sensing data in oceanic and <span class="hlt">continental</span> areas. The overall science objectives for the NASA Solid Earth Science plan for the 1990's, are to Understand the motion and deformation of the lithosphere within and across <span class="hlt">plate</span> boundaries'', and to understand the dynamics of the mantle, the structure and evolution of the lithosphere, and the landforms that result from local and regional deformation. 57 refs., 7 figs., 2 tabs.</p> <div class="credits"> <p class="dwt_author">Minster, B.; Prescott, W.; Royden, L.</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">202</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012IzPSE..48...93T"> <span id="translatedtitle">Bending deformations of <span class="hlt">plates</span> in the model of strong subduction earthquakes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The model of elastic rebound of thin <span class="hlt">plates</span> is considered to account for GPS-inferred surface deformation of <span class="hlt">plates</span> during subduction earthquakes on the example of the M9 earthquake that occurred in Japan in 2011. Due to the fact that the oceanic <span class="hlt">plate</span> moves together with a great mass of the convective mantle, it dips into the mantle at constant velocity all the time, both during the earthquakes and in the periods between them, although its coupling with the <span class="hlt">continental</span> <span class="hlt">plate</span> changes. The edge of the <span class="hlt">continental</span> <span class="hlt">plate</span> behaves as an elastic <span class="hlt">plate</span> that permanently bends under the action of the friction force on contact with the diving oceanic <span class="hlt">plate</span>. The bent <span class="hlt">plate</span> unbends after the earthquake. This leads to its thrusting over the subducting oceanic <span class="hlt">plate</span>. As a result, the island <span class="hlt">plate</span> moves towards the ocean, its island part sinks, and the oceanic <span class="hlt">plate</span> uplifts leading to a tsunami. The coordinates and magnitudes of the rise and subsidence correspond to the universal relations in the elastic <span class="hlt">plate</span> model. The breaking of coupling of the <span class="hlt">continental</span> <span class="hlt">plate</span> with the submarine mountains and a basaltic plateau of the dipping <span class="hlt">plate</span> is considered as a possible explanation of the anomalous properties of the strongest earthquakes. The main earthquake can be produced by partial destruction of a plateau or a large mountain. After this, the locked <span class="hlt">plates</span> become free along a great area in an avalanche-like manner, and the friction of rest gives place to sliding friction.</p> <div class="credits"> <p class="dwt_author">Trubitsyn, V. P.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">203</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010Earth...5....1B"> <span id="translatedtitle"><span class="hlt">Plate</span> tectonics conserves angular momentum</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A new combined understanding of <span class="hlt">plate</span> tectonics, Earth internal structure, and the role of impulse in deformation of the Earth's crust is presented. <span class="hlt">Plate</span> accelerations and decelerations have been revealed by iterative filtering of the quaternion history for the Euler poles that define absolute <span class="hlt">plate</span> motion history for the past 68 million years, and provide an unprecedented precision for <span class="hlt">plate</span> angular rotation variations with time at 2-million year intervals. Stage poles represent the angular rotation of a <span class="hlt">plate</span>'s motion between adjacent Euler poles, and from which the maximum velocity vector for a <span class="hlt">plate</span> can be determined. The consistent maximum velocity variations, in turn, yield consistent estimates of <span class="hlt">plate</span> accelerations and decelerations. The fact that the Pacific <span class="hlt">plate</span> was shown to accelerate and decelerate, implied that conservation of <span class="hlt">plate</span> tectonic angular momentum must be globally conserved, and that is confirmed by the results shown here (total angular momentum ~1.4+27 kg m2 s-1). Accordingly, if a <span class="hlt">plate</span> decelerates, other <span class="hlt">plates</span> must increase their angular momentums to compensate. In addition, the azimuth of the maximum velocity vectors yields clues as to why the "bend" in the Emperor-Hawaiian seamount trend occurred near 46 Myr. This report summarizes processing results for 12 of the 14 major tectonic <span class="hlt">plates</span> of the Earth (except for the Juan de Fuca and Philippine <span class="hlt">plates</span>). <span class="hlt">Plate</span> accelerations support the contention that <span class="hlt">plate</span> tectonics is a product of torques that most likely are sustained by the sinking of positive density anomalies revealed by geoid anomalies of the degree 4-10 packet of the Earth's spherical harmonic coefficients. These linear positive geoid anomalies underlie <span class="hlt">plate</span> subduction zones and are presumed due to phase changes in subducted gabbroic lithosphere at depth in the upper lower mantle (above 1200 km depth). The tectonic <span class="hlt">plates</span> are pulled along by the sinking of these positive mass anomalies, rather than moving at near constant velocity on the crests of convection cells driven by rising heat. The magnitude of these sinking mass anomalies is inferred also to be sufficient to overcome basal <span class="hlt">plate</span> and transform fault frictions. These results imply that spreading centers are primarily passive reactive features, and fracture zones (and wedge-shaped sites of seafloor spreading) are adjustment zones that accommodate strains in the lithosphere. Further, the interlocked pattern of the Australian and Pacific <span class="hlt">plates</span> the past 42 Million years (with their absolute <span class="hlt">plate</span> motions near 90° to each other) is taken as strong evidence that large thermally driven "roller" convection cells previously inferred as the driving mechanism in earlier interpretations of <span class="hlt">continental</span> drift and <span class="hlt">plate</span> tectonics, have not been active in the Earth's mantle the past 42 Million years, if ever. This report also presents estimates of the changes in location and magnitude of the Earth's axis of total <span class="hlt">plate</span> tectonic angular momentum for the past 62 million years.</p> <div class="credits"> <p class="dwt_author">Bowin, C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-03-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">204</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006Geo....34..893I"> <span id="translatedtitle">Feedback between mountain belt growth and <span class="hlt">plate</span> convergence</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">While it is generally assumed that global <span class="hlt">plate</span> motions are driven by the pattern of convection in the Earth's mantle, the details of that link remain obscure. Bouyancy forces associated with subduction of cool, dense lithosphere at zones of <span class="hlt">plate</span> convergence are thought to provide significant driving force, but the relative magnitudes of other driving and resisting forces are less clear, as are the main factors controlling long-term changes in <span class="hlt">plate</span> motion. The ability to consider past as well as present <span class="hlt">plate</span> motions provides significant additional constraints, because changes in <span class="hlt">plate</span> motion are necessarily driven by changes in one or more driving or resisting forces, which may be inferred from independent data. Here we present for the first time a model that explicitly links global mantle convection and lithosphere models to infer <span class="hlt">plate</span> motion changes as far back as Miocene time. By accurately predicting observed convergence rates over the past 10 m.y., we demonstrate that surface topography generated at convergent margins is a key factor controlling the long-term evolution of <span class="hlt">plate</span> motion. Specifically, the topographic load of large mountain belts and plateaus consumes a significant amount of the driving force available for <span class="hlt">plate</span> tectonics by increasing frictional forces between downgoing and <span class="hlt">overriding</span> <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Iaffaldano, Giampiero; Bunge, Hans-Peter; Dixon, Timothy H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-10-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">205</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.V43F..02S"> <span id="translatedtitle">Estimating the global volume of deeply recycled <span class="hlt">continental</span> crust at <span class="hlt">continental</span> collision zones</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">CRUSTAL RECYCLING AT OCEAN MARGINS: Large volumes of rock and sediment are missing from the submerged forearcs of ocean margin subduction zones--OMSZs. This observation means that (1) oceanic sediment is transported beneath the margin to either crustally underplate the coastal region or reach mantle depths, and that (2) the crust of the forearc is vertically thinned and horizontally truncated and the removed material transported toward the mantle. Transport of rock and sediment debris occurs in the subduction channel that separates the upper and lower <span class="hlt">plates</span>. At OMSZs the solid-volume flux of recycling crustal material is estimated to be globally ~2.5 km3/yr (i.e., 2.5 Armstrong units or AU). The corresponding rate of forearc truncation (migration of the trench axis toward a fix reference on the continent) is a sluggish 2-3 km/Myr (about 1/50th the orthogonal convergence rate). Nonetheless during the past 2.5 Gyr (i.e., since the beginning of the Proterozoic) a volume of <span class="hlt">continental</span> material roughly equal to the existing volume (~7 billion cubic km) has been recycled to the mantle at OMSZs. The amount of crust that has been destroyed is so large that recycling must have been a major factor creating the mapped rock pattern and age-fabric of <span class="hlt">continental</span> crust. RECYCLING AT CONTINENT/ARC COLLISIONS: The rate at which arc magmatism globally adds juvenile crust to OMSZs has been commonly globally estimated at ~1 AU. But new geophysical and dating information from the Aleutian and IBM arcs imply that the addition rate is at least ~5 AU (equivalent to ~125 km3/Myr/km of arc). If the Armstrong posit is correct that since the early Archean a balance has existed between additions and losses of crust, then a recycling sink for an additional 2-3 AU of <span class="hlt">continental</span> material must exist. As the exposure of exhumed masses of high P/T blueschist bodies documents that subcrustal streaming of <span class="hlt">continental</span> material occurs at OMSZs, so does the occurrence of exhumed masses of UHP metamorphic rock imply recycling also takes place at CCSZs. We thus target CCSZs as the setting for long-term crustal losses summing worldwide to 2-3 AU. An example is the ~10,000-km-long and 50-Myr duration of the Alpine- Himalaya CCSZ. Recycling is presumably effected by subduction (tectonic) erosion of the upper <span class="hlt">plate</span>, injection of lower <span class="hlt">plate</span> material into mantle circulation, and crustal delamination at collision-thickened orogenic welts. ALTERNATIVE MODEL: If the Armstrong assumption is incorrect and no long-term balance exist between the addition and losses of <span class="hlt">continental</span> crust, then significant crustal recycling at CCSZs may not occur and the global volume of arc-magmatically generated <span class="hlt">continental</span> crust has been growing with time.</p> <div class="credits"> <p class="dwt_author">Scholl, D. W.; Huene, R. V.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">206</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/intro/activities/23585.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Motions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">To prepare for this exercise students read the Chapter on <span class="hlt">plate</span> tectonics in their text book. In class, they are given a color isochron map of the sea floor. They are given 4 tasks: Answer basic questions about the timing and rate of opening of the N. and S. Atlantic; Determine what has happened to the oceanic crust that is created on the eastern side of the East Pacific Rise; Determine what type of <span class="hlt">plate</span> boundary existed on the western edge of the N. America <span class="hlt">plate</span> before the San Andreas Fault and when this transition occurred; and Reconstruct the motion of the <span class="hlt">plates</span> over the last 40 Ma assuming that the surface area of the Earth has not changed.</p> <div class="credits"> <p class="dwt_author">Nunn, Jeffrey</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">207</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/introgeo/earthhistory/platect.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary"><span class="hlt">Plate</span> tectonic activity is being observed presently on a historic timescale, especially in the form of volcanic eruptions and earthquakes, but, as with many large-scale Earth science phenomena, it is hard to ...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">208</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54720720"> <span id="translatedtitle">Blocks or Continuous Deformation in Large-Scale <span class="hlt">Continental</span> Geodynamics: Ptolemy Versus Copernicus, Kepler, and Newton (Invited)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The enhanced precision and resolution of GPS velocity fields within active <span class="hlt">continental</span> regions have highlighted two views of how best to describe these fields: (1) as relative movements of effectively rigid (or elastic) blocks, essentially <span class="hlt">plate</span> tectonics with many <span class="hlt">plates</span>, or (2) as continuous deformation of a (non-Newtonian) viscous fluid in a gravity field. The operative question is not: Are</p> <div class="credits"> <p class="dwt_author">P. H. Molnar</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">209</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54213383"> <span id="translatedtitle">Structure and Geochemistry of the <span class="hlt">Continental</span>-Oceanic Crust Boundary of the Red Sea and the Rifted Margin of Western Arabia</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The <span class="hlt">continental</span>-oceanic crust boundary and an incipient oceanic crust of the Red Sea opening are exposed within the Arabian <span class="hlt">plate</span> along a narrow zone of the Tihama Asir coastal plain in SW Saudi Arabia. Dike swarms, layered gabbros, granophyres and basalts of the 22 Ma Tihama Asir (TA) <span class="hlt">continental</span> margin ophiolite represent products of magmatic differentiation formed during the initial</p> <div class="credits"> <p class="dwt_author">Y. Dilek; H. Furnes; R. Schoenberg</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">210</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/6417029"> <span id="translatedtitle"><span class="hlt">Continental</span>-scale rheological heterogeneities and complex intraplate tectono-metamorphic patterns: insights from a case-study and numerical models</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Continental</span> <span class="hlt">plates</span> are built over long periods of time through successive extensional and compressional cycles. They are therefore rheologically heterogeneous. This heterogeneity should significantly influence the mechanical response of the <span class="hlt">continental</span> lithosphere during collision processes. The study of the Neoproterozoic Borborema shear zone system of northeast Brazil highlights a systematic link between marked changes in its tectono-metamorphic pattern and the</p> <div class="credits"> <p class="dwt_author">Andréa Tommasi; Alain Vauchez</p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">211</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51394417"> <span id="translatedtitle">Characterizing the southeast Caribbean-South American <span class="hlt">plate</span> boundary at 64°W</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The crustal and lithospheric structure of the northern South America <span class="hlt">plate</span> boundary with the southeast Caribbean has been the focus of many studies. In this region, westward subduction of (Atlantic) oceanic South America transitions to east-west transform between <span class="hlt">continental</span> South America and the Caribbean <span class="hlt">plate</span>. Previous models invoke a poorly-constrained component of north-south convergence between the Caribbean and <span class="hlt">continental</span> South</p> <div class="credits"> <p class="dwt_author">Stephen Anthony Clark</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">212</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.T23A1887S"> <span id="translatedtitle">Upper <span class="hlt">plate</span> controls on deep subduction, trench migrations and deformations at convergent margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Thus far, relatively simplistic models of free subduction, in which the trench and <span class="hlt">plate</span> motions are emergent features completely driven by the negative buoyancy of the slab, have investigated the dynamics of a single, isolated subducting <span class="hlt">plate</span>. Here we extend such models to incorporate an <span class="hlt">overriding</span> <span class="hlt">plate</span> and present the results of how such an <span class="hlt">overriding</span> <span class="hlt">plate</span> feedbacks into the dynamics of free subduction. In this study, we address three fundamental aspects of these dynamics: 1) how does the presence of an <span class="hlt">overriding</span> <span class="hlt">plate</span> change the force balance at the convergent margins? 2) How are the forces from deep subduction propagated to the surface? And 3) what controls the stress regime in a system of coupled upper and subducting <span class="hlt">plates</span> and how is it expressed in the deformations and <span class="hlt">plate</span> motions? In general, we find that the evolution of subduction zones is strongly controlled by both the interactions between the slab and the upper-lower mantle discontinuity as well as the strength of the upper <span class="hlt">plate</span>. When either the subducting or upper <span class="hlt">plates</span> are unable to move, subduction motions are steady-state and partitioned entirely into either slab rollback or <span class="hlt">plate</span> advance, respectively. When conditions favour a quasi-stationary trench, subducted lithosphere can form into a pile with multiple recumbent folds of slab material atop the lower mantle. Alternating between forwards- and backwards-draping slab, the corresponding horizontal trench motions at the surface are frontward and rearward, respectively, resulting in either a compressive or extensional regime in the back-arc. Time-dependent forcing arising from the slab piling behaviour can have a feedback with upper <span class="hlt">plate</span> and produce strongly non-steady state, intermittent phases of upper <span class="hlt">plate</span> deformation as those commonly observed on Earth. Two types of discontinuous back-arc strain evolution are identified: (1) periodic, when recurrent phases of strain over finite durations are accommodated by (viscous) stretching/thickening of the <span class="hlt">plate</span>, and (2) episodic, when upper <span class="hlt">plate</span> deformation localizes (plastic strain) and allows for punctuated episodes. These phases can include extension, quiescence, and compression, giving rise to a large variety of possible tectonic evolutions. The models presented here provide insight into the dynamics behind the non-steady state evolution of subduction, which can help unravel seemingly erratic motions of major convergent margins and back-arc deformations around the Pacific and Indian Oceans during the Cenozoic.</p> <div class="credits"> <p class="dwt_author">Sharples, W.; Capitanio, F. A.; Stegman, D.; Moresi, L. N.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">213</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5930257"> <span id="translatedtitle"><span class="hlt">Continental</span> rifts and mineral resources</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary"><span class="hlt">Continental</span> rifts are widespread and range in age from the present to 3 b.y. Individual rifts may form parts of complex systems as in E. Africa and the Basin and Range. Rifts have originated in diverse environments such as arc-crests, sites of <span class="hlt">continental</span> collision, collapsing mountain belts and on continents at rest over the mantle circulation pattern. <span class="hlt">Continental</span> rift resources can be classified by depth of origin: For example, in the Great Dike, Norilsk and Mwadui magma from the mantle is the host. At shallower depths <span class="hlt">continental</span> crust partly melted above mafic magma hosts ore (Climax, Henderson). Rift volcanics are linked to local hydrothermal systems and to extensive zeolite deposits (Basin and Range, East Africa). Copper (Zambia, Belt), zinc (Red Dog) and lead ores (Benue) are related to hydrothermal systems which involve hot rock and water flow through both pre-rift basement and sedimentary and volcanic rift fill. Economically significant sediments in rifts include coals (the Gondwana of Inida), marine evaporites (Lou Ann of the Gulf of Mexico) and non-marine evaporites (East Africa). Oil and gas in rifts relate to a variety of source, reservoir and trap relations (North Sea, Libya), but rift-lake sediment sources are important (Sung Liao, Bo Hai, Mina, Cabinda). Some ancient iron ores (Hammersley) may have formed in rift lakes but Algoman ores and greenstone belt mineral deposits in general are linked to oceanic and island arc environments. To the extent that <span class="hlt">continental</span> environments are represented in such areas as the Archean of the Superior and Slave they are Andean Arc environments which today have locally rifted crests (Ecuador, N. Peru). The Pongola, on Kaapvaal craton may, on the other hand represent the world's oldest preserved, little deformed, <span class="hlt">continental</span> rift.</p> <div class="credits"> <p class="dwt_author">Burke, K. (Univ. of Houston, TX (United States). Geosciences Dept.)</p> <p class="dwt_publisher"></p> <p class="publishDate">1992-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">214</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFM.T44A..01S"> <span id="translatedtitle">Crustal Recylcing at Ocean Margin and <span class="hlt">Continental</span> Subduction Zones and the Net Accumulation of <span class="hlt">Continental</span> Crust</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">CRUSTAL RECYCLING PROCESSES AND VOLUMES: At convergent ocean margins large volumes of rock and sediment are missing from the global length of submerged forearcs. Material is removed by the kindred tectonic process of sediment subduction and subduction erosion, both of which insert sediment and eroded crustal debris into the subduction channel separating the upper and lower <span class="hlt">plates</span>. The channel transports entrained debris toward the mantle where it is ultimately recycled. Large tracks of exposed high P/T rocks are exposed remnants of subduction channels. Over the past 100-200 my, the average solid-rock volume of recycled crust is estimated to have averaged globally 2.5-3.0 km3/yr--or 2.5 to 3 Armstrong Units (AU). Exposed tracts of UHP rocks at collisional orogens document that crustal material is subducted deep into the mantle at <span class="hlt">continental</span> subduction zones. Based on missing terranes of extended lower <span class="hlt">plate</span>, a volume of recycled <span class="hlt">continental</span> crust detached by slab failure can be estimated at ~5000 km3 for each km of the early Proterozoic Wopmay orogen of the NW Canadian Shield (Hildrenbrand and Bowring, 1999, Geology, v. 27, p.11-14). Averaged over an orogenic episode of ~40 my, the corresponding rate is ~125 km3/my/km of margin. Using the Wopmay- rate as a guide, and assuming that similar to the Cenozoic, collisional orogenic margins averaged 10-12,000 km in global length, then since the early Proterozoic crustal recycling at collisional subduction zones has averaged close to 1.5 AU (i.e., 1.5 km3/yr). Crustal losses from the upper <span class="hlt">plate</span> have also been recognized for sectors of the Variscan orogen (Oncken, 1998, Geology, v. 26, p. 1975-1078). The missing crust is roughly 40 km3/my for each km of upper <span class="hlt">plate</span>, thus globally tallying an additional ~0.5 AU. CRUSTAL GROWTH: New information implies that at intra-oceanic subduction zones the long-term (~50 my), global rate of arc magmatic productivity has averaged close to 5 AU, a much higher rate than formerly estimated (~1 AU). It is not clear that this rate, which is based on the growth of the Aleutian and Izu-Bonin-Mariana arc massifs corrected for subduction erosion losses, can be applied to <span class="hlt">continental</span> or Andean arcs. But allowing that it can, then the combined global rate of additions of juvenile igneous rock to build continents ( 5 AU) is similar to that recycled at ocean margin (2-3 AU) and <span class="hlt">continental</span> subduction zones (2 AU). Additional losses can arise from delamination of magmatically or tectonically thickened convergent-margin crust. The implication of these estimates and linked assumptions support the Armstrong posit that since the early Archean the yang of magmatic additions to the continents has been matched by the yin of recycling losses.</p> <div class="credits"> <p class="dwt_author">Scholl, D. W.; von Huene, R.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">215</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..14.5395D"> <span id="translatedtitle">Timing, rates and geodynamical conditions of <span class="hlt">continental</span> crust generation, destruction and reworking</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The timing, rates and the geodynamical conditions of <span class="hlt">continental</span> crust generation, destruction and reworking remain a topic of considerable debate. Around 7% of the present-day exposed crust consists of rocks of Archaean age, yet models of <span class="hlt">continental</span> growth suggest that 20-100% of the present-day volume of the <span class="hlt">continental</span> crust had formed by the end of the Archaean. <span class="hlt">Continental</span> growth models rely on understanding the balance between the generation of new crust and the reworking of old crust, and how these have changed with time throughout Earth's history. For that purpose, the variations in radiogenic isotope ratios in detrital rocks and minerals are a key archive. Two different approaches are considered to model the growth of continents: (1) the variation of Nd isotopes in <span class="hlt">continental</span> shales with various deposition ages, which requires a correction of the bias induced by preferential erosion of younger rocks through an erosion parameter 'K'; and (2) the variations in U-Pb, Hf and O isotopes in detrital zircons sampled worldwide. These two approaches independently suggest that the <span class="hlt">continental</span> crust was generated continuously, with a marked decrease in the <span class="hlt">continental</span> growth rate at ca. 3 Ga. The >4 Ga to ~3 Ga period is characterised by relatively high net rates of <span class="hlt">continental</span> growth (~3.0 km3.a-1), which are similar to the rates at which new crust is generated, and destroyed, at the present time. Since 3 Ga the net growth rates are much lower (~0.8 km3.a-1), and this may be attributed to higher rates of destruction of <span class="hlt">continental</span> crust. The inflexion in the <span class="hlt">continental</span> growth curve at ~3 Ga indicates a fundamental change in the way the crust was generated and preserved. This change may be linked to onset of subduction-driven <span class="hlt">plate</span> tectonics and discrete subduction zones.</p> <div class="credits"> <p class="dwt_author">Dhuime, B.; Hawkesworth, C. J.; Cawood, P. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">216</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.U33A0008F"> <span id="translatedtitle">The evolution of oceanic 87Sr/86Sr does not rule out early <span class="hlt">continental</span> growth</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Many contrasted <span class="hlt">continental</span> growth models have been proposed to date, in which the amount of <span class="hlt">continental</span> material extracted from the mantle at 3.8 Ga ranges between 0% (e.g. Taylor and McLennan, 1985) and 100% (e.g. Armstrong, 1981). One of the arguments in favor of delayed <span class="hlt">continental</span> growth models is the shift in the 87Sr/86Sr of marine carbonates from mantle composition at ~ 2.8 Ga (Shields and Veizer, 2002). When using oceanic 87Sr/86Sr as a proxy of <span class="hlt">continental</span> growth, the flux of strontium from the continents to the oceans is assumed to depend only on <span class="hlt">continental</span> area and both <span class="hlt">continental</span> hypsometry and <span class="hlt">continental</span> freeboard are assumed to be constant through time. However, Rey and Coltice (2008) suggested that Archean reliefs were lower than present-day ones and Flament et al. (2008) suggested that the emerged land area is not proportional to <span class="hlt">continental</span> growth. Therefore, the suitability of 87Sr/86Sr as a proxy of <span class="hlt">continental</span> growth must be re-assessed. In this contribution, we develop an integrated model, from the mantle to the surface, to investigate the effect of contrasted <span class="hlt">continental</span> growth models on the evolution of sea level, of the area of emerged land, and of oceanic 87Sr/86Sr. We estimate the evolution of mantle temperature using the model of Labrosse and Jaupart (2007) that takes the effect of <span class="hlt">continental</span> growth into account. The maximum <span class="hlt">continental</span> elevation is calculated using the results of Rey and Coltice (2008), sea level and the area of emerged land are calculated as in Flament et al. (2008), and the oceanic 87Sr/86Sr is calculated in a geochemical box model. We calculate Archean sea levels ~ 800 m higher than present for delayed <span class="hlt">continental</span> growth and ~ 1500 m higher for early <span class="hlt">continental</span> growth. In contrast, we calculate similar Archean areas of emerged land, of less than 5% of the Earth’s surface, for both early and delayed <span class="hlt">continental</span> growth models. Because the area of emerged land does not depend on <span class="hlt">continental</span> growth models, the evolution of oceanic 87Sr/86Sr is not a suitable proxy for <span class="hlt">continental</span> growth. We suggest that the delayed appearance of the differentiated reservoir in surface geochemical tracers reflects the emergence of the continents rather than a peak in extraction of juvenile <span class="hlt">continental</span> crust from the mantle. Therefore, there could be no need for delayed <span class="hlt">continental</span> growth models. Armstrong, R. L., 1981. Radiogenic isotopes: the case for crustal recycling on a near-steady-state no-<span class="hlt">continental</span>-growth. Earth. Philos. Trans. R. Soc. London 301, 443-471. Flament, N., Coltice, N., and Rey, P. F., 2008. A case for late-Archaean <span class="hlt">continental</span> emergence from thermal evolution models and hypsometry. Earth Planet. Sc. Lett. 275, 326-336. Labrosse, S., Jaupart, C., 2007. Thermal evolution of the Earth: Secular changes and fluctuations of <span class="hlt">plate</span> characteristics. Earth Planet. Sc. Lett. 260, 465-481. Rey, P. F. and Coltice N., 2008. Neoarchean strengthening of the lithosphere and the coupling of the Earth's geochemical reservoirs. Geology 36, 635-638. Taylor, S. R. and McLennan, S. M., 1985. The <span class="hlt">continental</span> crust: its composition and evolution. Blackwell Scientific Publications, 328 p.</p> <div class="credits"> <p class="dwt_author">Flament, N.; Coltice, N.; Rey, P. F.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">217</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/3906061"> <span id="translatedtitle">The heat flow through oceanic and <span class="hlt">continental</span> crust and the heat loss of the earth</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Oceans and continents are now considered to be mobile and interconnected. The paper discusses heat flow through the ocean floor, <span class="hlt">continental</span> heat flow, heat loss of the earth, thermal structure and thickness of the lithosphere, as well as convection in the mantle and the thermal structure of the lithosphere, within the framework of the theory of <span class="hlt">plate</span> tectonics. It is</p> <div class="credits"> <p class="dwt_author">J. G. Sclater; C. Jaupart; D. Galson</p> <p class="dwt_publisher"></p> <p class="publishDate">1980-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">218</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/41978095"> <span id="translatedtitle">Flexural behavior of the <span class="hlt">continental</span> lithosphere in Italy - Constraints imposed by gravity and deflection data</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This paper presents a simple model that describes the geometry of subducted <span class="hlt">continental</span> lithosphere as the result of flexural loading of a thin elastic sheet. The method involves a procedure for systematically matching the <span class="hlt">plate</span> flexure and gravity data to the best-fitting two-dimensional flexural geometry obtained by a thin elastic sheet of specified elastic strength. It is shown that the</p> <div class="credits"> <p class="dwt_author">Leigh Royden</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">219</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/gl/gl0714/2007GL029629/2007GL029629.pdf"> <span id="translatedtitle">Melt distribution beneath a young <span class="hlt">continental</span> rift: The Taupo Volcanic Zone, New Zealand</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Taupo Volcanic Zone (TVZ) is a zone of intense volcanism and rifting associated with the subduction of the Pacific <span class="hlt">Plate</span> beneath the <span class="hlt">continental</span> crust of New Zealand's North Island. An image of the conductivity structure beneath the central part of the TVZ has been constructed using 2-D inverse modeling of magnetotelluric data. A rapid increase in conductivity at a depth</p> <div class="credits"> <p class="dwt_author">Wiebke Heise; Hugh M. Bibby; T. Grant Caldwell; Stephen C. Bannister; Yasuo Ogawa; Shinichi Takakura; Toshihiro Uchida</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">220</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004Tecto..23.4011B"> <span id="translatedtitle">Anatomy and formation of oblique <span class="hlt">continental</span> collision: South Falkland basin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The South Falkland basin is a partially filled Cenozoic foreland basin located south of the Falkland Plateau. It was formed by flexure of this southern edge of the South American <span class="hlt">plate</span> when the load represented by Burdwood Bank collided. This <span class="hlt">continental</span> fragment belongs to the predominantly oceanic Scotia <span class="hlt">plate</span>. Flexure probably started in early Cenozoic times and has continued to the present day. The whole region is submarine and so the detailed stratigraphy and structure of the basin has been well imaged by seismic reflection profiling. The clarity of this imagery has made analysis of structures within the collision zone possible. The <span class="hlt">plate</span> boundary itself is an active oblique thrust fault which has controlled the growth of a frontal fold. There is evidence for older phases of thrusting and folding further south. Within and beneath the sediments which blanket the flexed South American <span class="hlt">plate</span>, normal faulting occurs on a variety of scales. Episodes of stratigraphic growth associated with the largest of these faults demonstrates that they were active during flexural bending. We have modeled the development of the South Falkland basin using two different approaches, both of which are based upon the simplest elastic model. Inverse modeling of free-air gravity and bathymetric profiles suggest that the elastic thickness of the loaded crust is 5-20 km. A complementary approach based upon the spectral analysis of free-air gravity and bathymetry shows that the elastic thickness is 15 ± 5 km. Both techniques indicate that the flexed <span class="hlt">continental</span> lithosphere is weak, a conclusion supported by the presence of normal faults within the flexed <span class="hlt">plate</span>. A small increase in elastic thickness from west to east appears consistent with a change in the density and penetration of normal faulting.</p> <div class="credits"> <p class="dwt_author">Bry, Madeleine; White, Nicky; Singh, Satish; England, Richard; Trowell, Carl</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-08-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_10");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a style="font-weight: bold;">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_12");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_11 div --> <div id="page_12" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_11");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a style="font-weight: bold;">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_13");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">221</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFM.U11D..01H"> <span id="translatedtitle">Tutorial: The EarthScope Investigation of <span class="hlt">Continental</span> Processes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">EarthScope is an integrated investigation of continents that uses the U.S. as the study region. Why the U.S.? It is one of the most fruitful subjects for study and it is our country. EarthScope is drilling the San Andreas Fault, geodetically measuring deformation in the tectonically active western U.S., and seismically imaging <span class="hlt">continental</span> lithosphere across the U.S. The goal is to understand the processes that create and shape continents, and an emphasis on earthquakes and volcanoes recognizes the scientific and social need to understand the underlying physics; these events are the fundamental agents in making continents and they pose genuine risk to society. Making significant progress toward these goals has proven elusive. In response, EarthScope has challenged our community to observe <span class="hlt">continental</span> structure and earthquake and volcanic cycles on continuous and wide spatial and temporal scales, and to bridge across disciplines to provide an intellectually broad and continuous understanding. As EarthScope begins its study of the western U.S., the following overview provides a framework for consideration; however, we are just on the verge of understanding how this marvelous system works. The western U.S. is one of Earth's major orogenic plateaus. Unlike most regions, deformation is distributed over a broad area. The origins of the distinctive western U.S. tectonic provinces can be traced back to <span class="hlt">continental</span> rifting 0.5 billion years ago, which created a <span class="hlt">continental</span> margin upon which tectonic and magmatic activity constructed a coherently heterogeneous land. Aftermaths of the Laramide (Rocky Mountain) event include the current weakness and high elevations of the western U.S. These, combined with applied <span class="hlt">plate</span>-tectonic loads at the <span class="hlt">plate</span> margin and a protecting effect of the strong Canadian craton, result in extension of the <span class="hlt">continental</span> interior (especially the very weak Basin and Range province), shear deformation across the westernmost swath of continent, and contraction in the Pacific Northwest as California moves north. Superimposed on and interacting with all this "<span class="hlt">plate</span> tectonic" activity is activity driven by vertical flow. The Yellowstone hotspot represents mantle upwelling. Its uplift has focused Basin and Range extension near Yellowstone, and lithosphere is being constructed rapidly. The Columbia River flood basalts (the dominant magmatic initiation of Yellowstone) probably occurred as old dense roots of the Wallowa batholith convectively destabilized and fell into the Earth ("delaminated"), apparently in response to initial Yellowstone upwelling. This delamination was similar to that occurring today beneath the rising southern Sierra Nevada. And lithospheric downwelling beneath southern California draws crust toward the Transverse Ranges.</p> <div class="credits"> <p class="dwt_author">Humphreys, E.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">222</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1513576L"> <span id="translatedtitle">Inheritance of pre-existing weakness in <span class="hlt">continental</span> breakup: 3D numerical modeling</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The whole process of <span class="hlt">continental</span> rifting to seafloor spreading is one of the most important <span class="hlt">plate</span> tectonics on the earth. There are many questions remained related to this process, most of which are poorly understood, such as how <span class="hlt">continental</span> rifting transformed into seafloor spreading? How the curved oceanic ridge developed from a single straight <span class="hlt">continental</span> rift? How the pre-existing weakness in either crust or lithospheric mantle individually influences the <span class="hlt">continental</span> rifting and oceanic spreading? By employing the state-of-the-art three-dimensional thermomechanical-coupled numerical code (using Eulerian-Lagrangian finite-difference method and marker-in-cell technic) (Gerya and Yuen, 2007), which can model long-term <span class="hlt">plate</span> extension and large strains, we studied the whole process of <span class="hlt">continental</span> rifting to seafloor spreading based on the following question: How the pre-existing lithospheric weak zone influences the <span class="hlt">continental</span> breakup? <span class="hlt">Continental</span> rifts do not occur randomly, but like to follow the pre-existing weakness (such as fault zones, suture zones, failed rifts, and other tectonic boundaries) in the lithosphere, for instance, the western branch of East African Rift formed in the relatively weak mobile belts along the curved western border of Tanzanian craton (Corti et al., 2007; Nyblade and Brazier, 2002), the Main Ethiopian Rift developed within the Proterozoic mobile belt which is believed to represent a <span class="hlt">continental</span> collision zone (Keranen and Klemperer, 2008),the Baikal rift formed along the suture between Siberian craton and Sayan-Baikal folded belt (Chemenda et al., 2002). The early stage formed rift can be a template for the future rift development and <span class="hlt">continental</span> breakup (Keranen and Klemperer, 2008). Lithospheric weakness can either reduce the crustal strength or mantle strength, and leads to the crustal or mantle necking (Dunbar and Sawyer, 1988), which plays an important role on controlling the <span class="hlt">continental</span> breakup patterns, such as controlling the breakup order of crust and mantle (Huismans and Beaumont, 2011). However, the inheritance of pre-existing lithospheric weakness in the evolution of <span class="hlt">continental</span> rifts and oceanic ridge is not well studied. We use 3D numerical modeling to study this problem, by changing the weak zone position and geometry, and the rheological structure of the model. In our study, we find that: 1).3D <span class="hlt">continental</span> breakup and seafloor spreading patterns are controlled by (a) crust-mantle rheological coupling and (b) geometry and position of the pre-existing weak zones. 2).Three spreading patterns are obtained: (a) straight ridges, (b) curved ridges and (c) overlapping ridges. 3).When crust and mantle are decoupled, abandoned rift structures often form.</p> <div class="credits"> <p class="dwt_author">Liao, Jie; Gerya, Taras</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">223</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6149382"> <span id="translatedtitle"><span class="hlt">Continental</span> crust beneath the Agulhas Plateau, Southwest Indian Ocean</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Agulhas Plateau lies 500 km off the Cape of Good Hope in the southwestern Indian Ocean. Acoustic basement beneath the northern one third of this large, aseismic structural high has rugged morphology, but basement in the south is anomalously smooth, excepting a 30- to 90-km-wide zone with irregular relief that trends south-southwest through the center of the plateau. Seismic refraction profiles across the southern plateau indicate that the zone of irregular acoustic basement overlies thickened oceanic crust and that <span class="hlt">continental</span> crust, locally thinned and intruded by basalts, underlies several regions of smooth acoustic basement. Recovery of quartzo-feldspathic gneisses in dredge hauls confirms the presence of <span class="hlt">continental</span> crust. The smoothness of acoustic basement probably results from erosion (perhaps initially subaerial) of topographic highs with depositions and cementation of debris in ponds to form high-velocity beds. Basalt flows and sills also may contribute locally to form smooth basement. The rugged basement of the northern plateau appears to be of oceanic origin. A <span class="hlt">plate</span> reconstruction to the time of initial opening of the South Atlantic places the <span class="hlt">continental</span> part of the southern plateau adjacent to the southern edge of the Falkland Plateau, and both abut the western Mozambique Ridge. Both the Agulhas and Falkland plateaus were displaced westward during initial rifting in the Early Cretaceous. Formation of an RRR triple junction at the northern edge of the Agulhas <span class="hlt">continental</span> fragment during middle Cretaceous time may explain the origin of the rugged, thickened oceanic crust beneath plateau as well as the apparent extension of the <span class="hlt">continental</span> crust and intrusion of basaltic magmas beneath the southern plateau.</p> <div class="credits"> <p class="dwt_author">Tucholke, B.E.; Houtz, R.E.; Barrett, D.M.</p> <p class="dwt_publisher"></p> <p class="publishDate">1981-05-10</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">224</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1999Tecto..18..895S"> <span id="translatedtitle">Tectonics of the Jurassic-Early Cretaceous magmatic arc of the north Chilean Coastal Cordillera (22°-26°S): A story of crustal deformation along a convergent <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The tectonic evolution of a <span class="hlt">continental</span> magmatic arc that was active in the north Chilean Coastal Cordillera in Jurassic-Early Cretaceous times is described in order to show the relationship between arc deformation and <span class="hlt">plate</span> convergence. During stage I (circa 195-155 Ma) a variety of structures formed at deep to shallow crustal levels, indicating sinistral arc-parallel strike-slip movements. From deep crustal levels a sequence of structures is described, starting with the formation of a broad belt of plutonic rocks which were sheared under granulite to amphibolite facies conditions (Bolfin Complex). The high-grade deformation was followed by the formation of two sets of conjugate greenschist facies shear zones showing strike-slip and thrust kinematics with a NW-SE directed maximum horizontal shortening, i.e., parallel to the probable Late Jurassic vector of <span class="hlt">plate</span> convergence. A kinematic pattern compatible to this <span class="hlt">plate</span> convergence is displayed by nonmetamorphic folds, thrusts, and high-angle normal faults which formed during the same time interval as the discrete shear zones. During stage II (160-150 Ma), strong arc-normal extension is revealed by brittle low-angle normal faults at shallow levels and some ductile normal faults and the intrusion of extended plutons at deeper levels. During stage III (155-147 Ma), two reversals in the stress regime took place indicated by two generations of dikes, an older one trending NE-SW and a younger one trending NW-SE. Sinistral strike-slip movements also prevailed during stage IV (until ˜125 Ma) when the Atacama Fault Zone originated as a sinistral trench-linked strike-slip fault. The tectonic evolution of the magmatic arc is interpreted in terms of coupling and decoupling between the downgoing and <span class="hlt">overriding</span> <span class="hlt">plates</span>. The structures of stages I and IV suggest that stress transmission due to seismic coupling between the <span class="hlt">plates</span> was probably responsible for these deformations. However, decoupling of the <span class="hlt">plates</span> occurred possibly due to a decrease in convergence rate resulting in extension and the reversals of stages II and III.</p> <div class="credits"> <p class="dwt_author">Scheuber, Ekkehard; Gonzalez, Gabriel</p> <p class="dwt_publisher"></p> <p class="publishDate">1999-10-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">225</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17051208"> <span id="translatedtitle">Evolution of the <span class="hlt">continental</span> crust.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">The <span class="hlt">continental</span> crust covers nearly a third of the Earth's surface. It is buoyant--being less dense than the crust under the surrounding oceans--and is compositionally evolved, dominating the Earth's budget for those elements that preferentially partition into silicate liquid during mantle melting. Models for the differentiation of the <span class="hlt">continental</span> crust can provide insights into how and when it was formed, and can be used to show that the composition of the basaltic protolith to the <span class="hlt">continental</span> crust is similar to that of the average lower crust. From the late Archaean to late Proterozoic eras (some 3-1 billion years ago), much of the <span class="hlt">continental</span> crust appears to have been generated in pulses of relatively rapid growth. Reconciling the sedimentary and igneous records for crustal evolution indicates that it may take up to one billion years for new crust to dominate the sedimentary record. Combining models for the differentiation of the crust and the residence time of elements in the upper crust indicates that the average rate of crust formation is some 2-3 times higher than most previous estimates. PMID:17051208</p> <div class="credits"> <p class="dwt_author">Hawkesworth, C J; Kemp, A I S</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-10-19</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">226</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52340368"> <span id="translatedtitle">Earth's <span class="hlt">continental</span> crustal gold endowment</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The analysis of the temporal distribution of gold deposits, combined with gold production data as well as reserve and resource estimates for different genetic types of gold deposit, revealed that the bulk of the gold known to be concentrated in ore bodies was added to the <span class="hlt">continental</span> crust during a giant Mesoarchaean gold event at a time (3 Ga) when</p> <div class="credits"> <p class="dwt_author">H. E. Frimmel</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">227</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40850678"> <span id="translatedtitle">Earth's <span class="hlt">continental</span> crustal gold endowment</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The analysis of the temporal distribution of gold deposits, combined with gold production data as well as reserve and resource estimates for different genetic types of gold deposit, revealed that the bulk of the gold known to be concentrated in ore bodies was added to the <span class="hlt">continental</span> crust during a giant Mesoarchaean gold event at a time (3 Ga) when the</p> <div class="credits"> <p class="dwt_author">H. E. Frimmel</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">228</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/47387279"> <span id="translatedtitle">A perspective view on ultrahigh-pressure metamorphism and <span class="hlt">continental</span> collision in the Dabie-Sulu orogenic belt</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The study of <span class="hlt">continental</span> deep-subduction has been one of the forefront and core subjects to advance the <span class="hlt">plate</span> tectonics theory\\u000a in the twenty-first century. The Dabie-Sulu orogenic belt in China crops out the largest lithotectonic unit containing ultrahigh-pressure\\u000a metamorphic rocks in the world. Much of our understanding of the world’s most enigmatic processes in <span class="hlt">continental</span> deep-subduction\\u000a zones has been deduced</p> <div class="credits"> <p class="dwt_author">YongFei Zheng</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">229</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://patft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=1&p=1&f=G&l=50&d=PTXT&S1=%22femoral+locking+compression+plate%22&OS=%22femoral+locking+compression+plate%22&RS=%22femoral+locking+compression+plate%22"> <span id="translatedtitle">Bone <span class="hlt">plate</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://patft.uspto.gov/netahtml/PTO/search-adv.htm">US Patent & Trademark Office Database</a></p> <p class="result-summary">A bone <span class="hlt">plate</span> assembly and method of use comprising a head; a shaft; an upper surface; a lower surface having a fixed plane intended to be adjacent to the patient's bone when the <span class="hlt">plate</span> is in use; a first hole positioned in the head wherein the first hole passes through the upper and lower surfaces and is configured to fix a shaft of a first bone anchor along a first axis; a second hole positioned on the anterior portion of the upper surface of the head wherein the second hole passes through the upper and lower surfaces and is configured to fix a shaft of a second bone anchor along a second axis; and a third hole positioned in the posterior side of the head wherein the third hole passes through the upper and lower surfaces and is configured to fix a shaft of a third bone anchor along a third axis, wherein the first axis, the second axis and the third axis do not intersect in the bone when the <span class="hlt">plate</span> is in use.</p> <div class="credits"> <p class="dwt_author">Gehlert; Rick J. (Albuquerque, NM)</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-09-18</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">230</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60232505"> <span id="translatedtitle">CSDP: Seismology of <span class="hlt">continental</span> thermal regime</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This is a progress report for the past one year of research (year 2 of 5-year project) under the project titled CSDP: Seismology of <span class="hlt">Continental</span> Thermal Regime'', in which we proposed to develop seismological interpretation theory and methods applicable to complex structures encountered in <span class="hlt">continental</span> geothermal areas and apply them to several candidate sites for the <span class="hlt">Continental</span> Scientific Drilling Project.</p> <div class="credits"> <p class="dwt_author">Aki</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">231</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60219809"> <span id="translatedtitle">CSDP: The seismology of <span class="hlt">continental</span> thermal regimes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This is a progress report for the past one year of research (year 3 of 5-year project) under the project titled CSDP: Seismology of <span class="hlt">Continental</span> Thermal Regime'', in which we proposed to develop seismological interpretation theory and methods applicable to complex structures encountered in <span class="hlt">continental</span> geothermal areas and apply them to several candidate sites for the <span class="hlt">Continental</span> Scientific Drilling Project.</p> <div class="credits"> <p class="dwt_author">Aki</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">232</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2121042"> <span id="translatedtitle">Plus-end motors <span class="hlt">override</span> minus-end motors during transport of squid axon vesicles on microtubules</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">Plus- and minus-end vesicle populations from squid axoplasm were isolated from each other by selective extraction of the minus-end vesicle motor followed by 5'-adenylyl imidodiphosphate (AMP-PNP)- induced microtubule affinity purification of the plus-end vesicles. In the presence of cytosol containing both plus- and minus-end motors, the isolated populations moved strictly in opposite directions along microtubules in vitro. Remarkably, when treated with trypsin before incubation with cytosol, purified plus-end vesicles moved exclusively to microtubule minus ends instead of moving in the normal plus-end direction. This reversal in the direction of movement of trypsinized plus-end vesicles, in light of further observation that cytosol promotes primarily minus-end movement of liposomes, suggests that the machinery for cytoplasmic dynein-driven, minus-end vesicle movement can establish a functional interaction with the lipid bilayers of both vesicle populations. The additional finding that kinesin <span class="hlt">overrides</span> cytoplasmic dynein when both are bound to bead surfaces indicates that the direction of vesicle movement could be regulated simply by the presence or absence of a tightly bound, plus-end kinesin motor; being processive and tightly bound, the kinesin motor would <span class="hlt">override</span> the activity of cytoplasmic dynein because the latter is weakly bound to vesicles and less processive. In support of this model, it was found that (a) only plus-end vesicles copurified with tightly bound kinesin motors; and (b) both plus- and minus-end vesicles bound cytoplasmic dynein from cytosol.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1996-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">233</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.teachersdomain.org/resource/ess05.sci.ess.earthsys.boundaries/"> <span id="translatedtitle">Tectonic <span class="hlt">Plates</span> and <span class="hlt">Plate</span> Boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Continents were once thought to be static, locked tight in their positions in Earth's crust. Similarities between distant coastlines, such as those on opposite sides of the Atlantic, were thought to be the work of a scientist's overactive imagination, or, if real, the result of erosion on a massive scale. This interactive feature shows 11 tectonic <span class="hlt">plates</span> and their names, the continents that occupy them, and the types of boundaries between them.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2011-05-09</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">234</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pbslearningmedia.org/resource/ess05.sci.ess.earthsys.boundaries/"> <span id="translatedtitle">Tectonic <span class="hlt">Plates</span> and <span class="hlt">Plate</span> Boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Continents were once thought to be static, locked tight in their positions in Earth's crust. Similarities between distant coastlines, such as those on opposite sides of the Atlantic, were thought to be the work of a scientist's overactive imagination, or, if real, the result of erosion on a massive scale. This interactive feature shows 11 tectonic <span class="hlt">plates</span> and their names, the continents that occupy them, and the types of boundaries between them.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">235</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1987JGR....9213903S"> <span id="translatedtitle">A high-resolution local network study of the Nazca <span class="hlt">plate</span> Wadati-Benioff zone under western Argentina</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Seismic data, recorded by INPRES telemetered network located above one of the subhorizontal segments of the subducted Nazca <span class="hlt">plate</span> Wadati-Benioff zone beneath western Argentina, were analyzed to determine the zone's fine structure. The depth of the center and the thickness of the subhorizontal Wadati-Benioff zone beneath the network were calculated to be about 107 km and about 20 km, respectively, with most of the seismogenic zone concentrated in a region about 12 km thick. The Nazca <span class="hlt">plate</span> is interpreted to be in a state of down-dip tension and to be decoupled from the <span class="hlt">overriding</span> South American <span class="hlt">plate</span> by a weak zone of asthenospheric or shear-heated material. The South American <span class="hlt">plate</span> is estimated to be 80 km thick, based on the location of the subducted Nazca <span class="hlt">plate</span> and an inferred decoupling zone between the <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Smalley, Robert F., Jr.; Isacks, Bryan L.</p> <p class="dwt_publisher"></p> <p class="publishDate">1987-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">236</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48651489"> <span id="translatedtitle">Geodetic analysis of motion at a convergent <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A simplistic model of the superficial interaction between two lithospheric <span class="hlt">plates</span> would comprise two rigid bodies separated by a linear discontinuity. Where <span class="hlt">continental</span> crust straddles an obliquely convergent boundary, however, as in New Zealand, extensive deformation can be seen over a zone several hundred kilometres in width. Past analyses of repeated geodetic surveys have indicated that shear-strain may be occurring</p> <div class="credits"> <p class="dwt_author">W. I. Reilly</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">237</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007PEPI..163...35L"> <span id="translatedtitle">Parallel computing of multi-scale <span class="hlt">continental</span> deformation in the Western United States: Preliminary results</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Lithospheric deformation in the western United States is one of the best examples of diffuse <span class="hlt">continental</span> tectonics that deviate from the <span class="hlt">plate</span> tectonics paradigm. Conceptually, diffuse <span class="hlt">continental</span> deformation is known to result from (1) weak and heterogeneous rheology of continents and (2) driving forces that arise from <span class="hlt">plate</span> boundaries as well as within the <span class="hlt">continental</span> lithosphere. However, the dynamic interplay of <span class="hlt">continental</span> rheology and driving forces, hence the geodynamics of <span class="hlt">continental</span> tectonics, remains poorly understood. The heterogeneous rheology and multiple driving forces cause continents to deform over different spatiotemporal scales with different physical processes, yet most geodynamic models for <span class="hlt">continental</span> tectonic avoid dealing with such multiphysics partly because of (1) the limited observational constraints of lithospheric structure and deformation, and (2) high demands on computing algorithms and resources. These constraints, however, have relaxed significantly in recent years to permit exploration of some of the multi-scale physics governing <span class="hlt">continental</span> tectonics. Here we present preliminary results of modeling multi-scale tectonics in the western United States using parallel finite element computation. In a 3D subcontinental-scale model, we used fine numerical meshes to incorporate all major tectonic boundaries and rheological heterogeneities in the model to explore their interplay with tectonic driving forces in controlling active tectonics in the western US. In another model for the entire San Andreas Fault system, we explored strain localization and simulated fault behavior at multi-timescales ranging from rupture in seconds to secular fault creep in tens of thousands of years. These models can help to integrate data grids with distributed high-performance computing resources in the emerging geosciences cyberinfrastructure.</p> <div class="credits"> <p class="dwt_author">Liu, Mian; Yang, Youqing; Li, Qingsong; Zhang, Huai</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-08-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">238</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/55280984"> <span id="translatedtitle">Monitoring the northern Chile megathrust with the Integrated <span class="hlt">Plate</span> boundary Observatory Chile (IPOC)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The oceanic Nazca <span class="hlt">plate</span> subducts beneath the <span class="hlt">continental</span> South American <span class="hlt">plate</span> by recurrent rupture of large segments of its interface. The resulting earthquakes are among the largest and most frequent on Earth. Along the Chilean and southern Peruvian margin, all sizeable segments have ruptured at least once in the past 150 years for which there exist historic and\\/or instrumental records.</p> <div class="credits"> <p class="dwt_author">Bernd Schurr; Günter Asch; Beatrice Cailleau; Guillermo Chong Diaz; Sergio Barrientos; Jean-Pierre Vilotte; Onno Oncken</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">239</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51505318"> <span id="translatedtitle">The International <span class="hlt">Plate</span> Boundary Observatory Chile (IPOC) in the northern Chile seismic gap</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Fast convergence between the oceanic Nazca and the <span class="hlt">continental</span> South American <span class="hlt">plate</span> is accommodated by recurrent rupture of large segments of the two <span class="hlt">plates</span>' interface. The resulting earthquakes are among the largest and, for their sizes, most frequent on Earth. Along the Chilean and southern Peruvian margin, all segments have ruptured at least once in the past 150 years for</p> <div class="credits"> <p class="dwt_author">B. Schurr; A. Asch; F. Sodoudi; A. Manzanares; O. Ritter; J. Klotz; G. Chong-Diaz; S. Barrientos; J.-P. Villotte; O. Oncken</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">240</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52232014"> <span id="translatedtitle"><span class="hlt">Plate</span>-tectonic Regulation of Faunal Diversity and Sea Level: a Model</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A GROWING body of evidence and theory supports the idea that processes of <span class="hlt">plate</span> tectonics have been operating for the past 3 × 109 years1. The hypothesis of ocean-driven <span class="hlt">plates</span> implies that certain mountain systems represent the remains of former large ocean basins. An important corollary of this notion is that the history of <span class="hlt">continental</span> assembly and fragmentation can be</p> <div class="credits"> <p class="dwt_author">J. W. Valentine; E. M. Moores</p> <p class="dwt_publisher"></p> <p class="publishDate">1970-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_11");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a style="font-weight: bold;">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_13");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_12 div --> <div id="page_13" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_12");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a style="font-weight: bold;">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_14");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">241</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.5049C"> <span id="translatedtitle">The role of <span class="hlt">continental</span> growth on the evolution of seafloor spreading</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The area vs. seafloor age distribution is fundamental information to build <span class="hlt">plate</span> reconstructions and evaluate sea level changes and heat flow evolution. Recent models of spherical mantle convection with <span class="hlt">plate</span>-like behavior (Tackley, 2000a, 2000b) and <span class="hlt">continental</span> drift (Rolf and Tackley, 2011) propose solutions compatible with the area vs. age distribution of present-day seafloor spreading (Coltice et al., 2012). Area vs. age distributions computed in convection models display fluctuations of the rate of seafloor spreading. The shape of the distribution varies from uniformly distributed to strongly dominated by younger ages over the course of a calculation. Two factors influence the computed area vs. age distribution: the time-dependence of the rate of production of new seafloor and the <span class="hlt">continental</span> area that constrains the geometry of ocean basins. Heat flow or sea level strongly depend on the shape of this distribution; hence it is essential to investigate how <span class="hlt">continental</span> growth could have modified the area vs. age distribution. We will evaluate the role of increasing <span class="hlt">continental</span> area on the computed seafloor spreading histories. We will show that the average production rate of new seafloor does not vary with <span class="hlt">continental</span> area, contrarily to fluctuations that increase with <span class="hlt">continental</span> area. We will show <span class="hlt">continental</span> growth tends to favour the consumption of progressively younger seafloor. Consequences on heat flow and sea level will be presented. References Coltice, N., Rolf, T., Tackley P.J., Labrosse, S., Dynamic causes of the relation between area and age of the ocean floor, Science 336, 335-338 (2012). Rolf, T., and P. J. Tackley, Focussing of stress by continents in 3D spherical mantle convection with self-consistent <span class="hlt">plate</span> tectonics, Geophys. Res. Lett., 38 (2011). Tackley, P.J., Self-consistent generation of tectonic <span class="hlt">plates</span> in time-dependent, three-dimensional mantle convection simulations, part 1: Pseudoplastic yielding, Geoch. Geophys. Geosys. 1 (2000a). Tackley, P.J., Self-consistent generation of tectonic <span class="hlt">plates</span> in time-dependent, three-dimensional mantle convection simulations, part 2: Strain weakening and asthenosphere, Geochem. Geophys. Geosys. 1, (2000b).</p> <div class="credits"> <p class="dwt_author">Coltice, Nicolas; Rolf, Tobias; Tackley, Paul J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">242</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011E%26PSL.302..267A"> <span id="translatedtitle">Fluid migration in <span class="hlt">continental</span> subduction: The Northern Apennines case study</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Subduction zones are the place in the world where fluids are transported from the foredeep to the mantle and back-to-the-surface in the back-arc. The subduction of an oceanic <span class="hlt">plate</span> implies the transportation of the oceanic crust to depth and its methamorphization. Oceanic sediments release water in the (relatively) shallower part of the subduction zone, while dehydration of the subducted basaltic crust allows fluid circulation at larger depths. While the water budget in oceanic subduction has been deeply investigated, less attention has been given to the fluids implied in the subduction of a <span class="hlt">continental</span> margin (i.e. in <span class="hlt">continental</span> subduction). In this study, we use teleseismic receiver function (RF) analysis to image the process of water migration at depth, from the subducting <span class="hlt">plate</span> to the mantle wedge, under the Northern Apennines (NAP, Italy). Harmonic decomposition of the RF data-set is used to constrain both isotropic and anisotropic structures. Isotropic structures highlight the subduction of the Adriatic lower crust under the NAP orogens, from 35-40 km to 65 km depth, as a dipping low S-velocity layer. Anisotropic structures indicate the presence of a broad anisotropic zone (anisotropy as high as 7%). This zone develops in the subducted Adriatic lower crust and mantle wedge, between 45 and 65 km depth, directly beneath the orogens and the more recent back-arc extensional basin. The anisotropy is related to the metamorphism of the Adriatic lower crust (gabbro to blueschists) and its consequent eclogitization (blueschists to eclogite). The second metamorphic phase releases water directly in the mantle wedge, hydrating the back-arc upper mantle. The fluid migration process imaged in this study below the northern Apennines could be a proxy for understanding other regions of ongoing <span class="hlt">continental</span> subduction.</p> <div class="credits"> <p class="dwt_author">Agostinetti, Nicola Piana; Bianchi, Irene; Amato, Alessandro; Chiarabba, Claudio</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">243</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011GeoJI.184...43B"> <span id="translatedtitle">Subduction and exhumation of <span class="hlt">continental</span> crust: insights from laboratory models</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">When slivers of <span class="hlt">continental</span> crust and sediment overlying oceanic lithosphere enter a subduction zone, they may be scraped off at shallow levels, subducted to depths of up to 100-200 km and then exhumed as high pressure (HP) and ultra-high pressure (UHP) rocks, or subducted and recycled in the mantle. To investigate the factors that influence the behaviour of subducting slivers of <span class="hlt">continental</span> material, we use 3-D dynamically consistent laboratory models. A laboratory analogue of a slab-upper mantle system is set up with two linearly viscous layers of silicone putty and glucose syrup in a tank. A sliver of <span class="hlt">continental</span> material, also composed of silicone putty, overlies the subducting lithosphere, separated by a syrup detachment. The density of the sliver, viscosity of the detachment, geometry of the subducting system (attached <span class="hlt">plate</span> versus free ridge) and dimensions of the sliver are varied in 34 experiments. By varying the density of the sliver and viscosity of the detachment, we can reproduce a range of sliver behaviour, including subduction, subduction and exhumation from various depths and offscraping. Sliver subduction and exhumation requires sufficient sliver buoyancy and a detachment that is strong enough to hold the sliver during initial subduction, but weak enough to allow adequate sliver displacement or detachment for exhumation. Changes to the system geometry alter the slab dip, subduction velocity, pattern of mantle flow and amount of rollback. Shallower slab dips with more trench rollback produce a mantle flow pattern that aids exhumation. Steeper slab dips allow more buoyancy force to be directed in the up-dip direction of the plane of the <span class="hlt">plate</span>, and aide exhumation of subducted slivers. Slower subduction can also aide exhumation, but if slab dip is too steep or subduction too slow, the sliver will subduct to only shallow levels and not exhume. Smaller slivers are most easily subducted and exhumed and influenced by the mantle flow.</p> <div class="credits"> <p class="dwt_author">Bialas, Robert W.; Funiciello, Francesca; Faccenna, Claudio</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">244</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6206084"> <span id="translatedtitle">Current <span class="hlt">plate</span> velocities relative to the hotspots incorporating the NUVEL-1 global <span class="hlt">plate</span> motion model</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">NUVEL-1 is a new global model of current relative <span class="hlt">plate</span> velocities which differ significantly from those of prior models. Here the authors incorporate NUVEL-1 into HS2-NUVEL1, a new global model of <span class="hlt">plate</span> velocities relative to the hotspots. HS2-NUVEL1 was determined from the hotspot data and errors used by Minster and Jordan (1978) to determine AM1-2, which is their model of <span class="hlt">plate</span> velocities relative to the hotspots. AM1-2 is consistent with Minster and Jordan's relative <span class="hlt">plate</span> velocity model RM2. Here the authors compare HS2-NUVEL1 with AM1-2 and examine how their differences relate to differences between NUVEL-1 and RM2. HS2-NUVEL1 <span class="hlt">plate</span> velocities relative to the hotspots are mainly similar to those of AM1-2. Minor differences between the two models include the following: (1) in HS2-NUVEL1 the speed of the partly <span class="hlt">continental</span>, apparently non-subducting Indian <span class="hlt">plate</span> is greater than that of the purely oceanic, subducting Nazca <span class="hlt">plate</span>; (2) in places the direction of motion of the African, Antarctic, Arabian, Australian, Caribbean, Cocos, Eurasian, North American, and South American <span class="hlt">plates</span> differs between models by more than 10{degree}; (3) in places the speed of the Australian, Caribbean, Cocos, Indian, and Nazca <span class="hlt">plates</span> differs between models by more than 8 mm/yr. Although 27 of the 30 RM2 Euler vectors differ with 95% confidence from those of NUVEL-1, only the AM1-2 Arabia-hotspot and India-hotspot Euler vectors differ with 95% confidence from those of HS2-NUVEL1. Thus, substituting NUVEL-1 for RM2 in the inversion for <span class="hlt">plate</span> velocities relative to the hotspots changes few Euler vectors significantly, presumably because the uncertainty in the velocity of a <span class="hlt">plate</span> relative to the hotspots is much greater than the uncertainty in its velocity relative to other <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Gripp, A.E.; Gordon, R.G. (Northwestern Univ., Evanston, IL (USA))</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-07-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">245</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3233849"> <span id="translatedtitle">Heat acclimation and exercise training interact when combined in an <span class="hlt">overriding</span> and trade-off manner: physiologic-genomic linkage</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">Combined heat acclimation (AC) and exercise training (EX) enhance exercise performance in the heat while meeting thermoregulatory demands. We tested the hypothesis that different stress-specific adaptations evoked by each stressor individually trigger similar cardiac alterations, but when combined, <span class="hlt">overriding</span>/trade-off interactions take place. We used echocardiography, isolated cardiomyocyte imaging and cDNA microarray techniques to assay in situ cardiac performance, excitation-contraction (EC) coupling features, and transcriptional programs associated with cardiac contractility. Rat groups studied were controls (sedentary 24°C); AC (sedentary, 34°C, 1 mo); normothermic EX (treadmill at 24°C, 1 mo); and heat-acclimated, exercise-trained (EXAC; treadmill at 34°C, 1 mo). Prolonged heat exposure decreased heart rate and contractile velocity and increased end ventricular diastolic diameter. Compared with controls, AC/EXAC cardiomyocytes demonstrated lower l-type Ca2+ current (ICaL) amplitude, higher Ca2+ transient (Ca2+T), and a greater Ca2+T-to-ICaL ratio; EX alone enhanced ICaL and Ca2+T, whereas aerobic training in general induced cardiac hypertrophy and action potential elongation in EX/EXAC animals. At the genomic level, the transcriptome profile indicated that the interaction between AC and EX yields an EXAC-specific molecular program. Genes affected by chronic heat were linked with the EC coupling cascade, whereas aerobic training upregulated genes involved with Ca2+ turnover via an adrenergic/metabolic-driven positive inotropic response. In the EXAC cardiac phenotype, the impact of chronic heat <span class="hlt">overrides</span> that of EX on EC coupling components and heart rate, whereas EX regulates cardiac morphometry. We suggest that concerted adjustments induced by AC and EX lead to enhanced metabolic and mechanical performance of the EXAC heart.</p> <div class="credits"> <p class="dwt_author">Kodesh, Einat; Nesher, Nir; Simaan, Assi; Hochner, Benny; Beeri, Ronen; Gilon, Dan; Stern, Michael D.; Gerstenblith, Gary</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">246</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009GeoJI.179.1341H"> <span id="translatedtitle">Anisotropy of the Indian <span class="hlt">continental</span> lithospheric mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Due to the paucity of seismological data available in the public domain, the structure of the Indian lithosphere is still little known. We investigate the lithospheric structure and potential mechanical coupling between the crust and upper mantle along the Himalayan arc and underneath peninsular India using seismic anisotropy. Shear wave splitting measurements are performed on core-refracted phases. For each event recorded at a given seismological station we measured the orientation of the polarization plane of the fast S wave (phi), assumed to be a proxy for the orientation of the a axis of olivine, and the delay (dt) between the arrival time of the fast and slow S waves. We present a very comprehensive data set recorded at 86 seismological stations, deployed from the Himalayas to the southern tip of the Indian peninsula, in a joint effort by the National Geophysical Research Institute, Hyderabad, India, the University of Cambridge and the Indian Institute of Astrophysics. The unprecedented data set we present sheds light on the mechanisms involved in the India-Eurasia <span class="hlt">continental</span> collision in a region along the Himalayan arc, south of the Indus-Tsangpo suture zone. At the scale of the Indian <span class="hlt">plate</span>, the majority of the stations show a NNE-SSW orientation of phi over hundreds of kilometres, from Sri Lanka to the northern part of the Dharwar craton. This direction closely parallels the trend of the Indian <span class="hlt">plate</span> motion, with respect to a fixed Eurasian <span class="hlt">plate</span>, as defined through the NUVEL1A <span class="hlt">plate</span> model. Along the Himalayan arc, from Ladakh in the northwest, to Bhutan and the Shillong plateau in the east, the orientation of phi rotates to become ~EW, perpendicular to the <span class="hlt">plate</span> motion as defined through NUVEL1A. Unlike previous studies, we do find strong evidence for seismic anisotropy south of the Indus Tsangpo suture zone. A large number of null results have been computed, with consistent orientation of the two fast polarization directions (phi) across the subcontinent. We demonstrate the potential value of the too often neglected null measurements in the interpretation of seismic anisotropy. From these results, we infer the dominance, beneath the Indian lithosphere, of the asthenospheric flow in aligning minerals in the sheared lithosphere-asthenosphere boundary layer, masking any compression induced anisotropy expected to be normal to this direction. Closer to the collision front in northern India, the anisotropy may in part, be due to the foliation planes of the Himalayan fold and thrust belt aligning the a axis of olivine perpendicular to the compression axis, but more likely to the turning of the relative asthenospheric flow along the strike caused by the downthrusting Indian lithosphere acting as a barrier. The continent-wide consistency of results strengthens the understanding that the Indian lithosphere has distinct anisotropic signatures, contrary to the hitherto assumed isotropy and allows one to interpret the results in a coherent framework of Indo-Eurasian convergence.</p> <div class="credits"> <p class="dwt_author">Heintz, Maggy; Kumar, V. Pavan; Gaur, Vinod K.; Priestley, Keith; Rai, Shyam S.; Prakasam, K. Surya</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">247</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFMDI11A2136A"> <span id="translatedtitle">Multi-Scale Dynamics and Rheology of Mantle Flow With <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Several issues fundamental to our understanding of the dynamics of the mantle and <span class="hlt">plates</span> remain unresolved, such as the rheology and state of stress of <span class="hlt">plates</span> and slabs; the coupling between <span class="hlt">plates</span>, slabs and mantle; and the flow around slabs. To address these questions, we develop numerical models of global mantle flow with <span class="hlt">plates</span>, using the adaptive finite element code Rhea. These dynamically consistent instantaneous models incorporate as much detail in the thermal buoyancy field as possible, and include a composite rheology with yielding. Around <span class="hlt">plate</span> boundaries, the local resolution is 1 km. This high resolution allows us to study highly detailed regional features in a globally consistent framework. We investigate competing effects of regional characteristics and global rheology parameters on mantle dynamics. As a first order test of the results, we explore the effects of changes in global rheology parameters on <span class="hlt">plate</span> motions on global and regional scales, <span class="hlt">plateness</span>, and net surface rotation. Models that best fit <span class="hlt">plateness</span> criteria and <span class="hlt">plate</span> motion data have strong slabs with high stresses. Furthermore, we assess the models using the strain rates and the state of stress in slabs and <span class="hlt">overriding</span> <span class="hlt">plates</span>. The details of regional slab dynamics are studied by investigating the flow in and around slabs together with microplate behaviour and trench rollback.</p> <div class="credits"> <p class="dwt_author">Alisic, L.; Gurnis, M.; Stadler, G.; Burstedde, C.; Wilcox, L.; Ghattas, O.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">248</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54169667"> <span id="translatedtitle">The General Theory of <span class="hlt">Plate</span> Tectonics; No Role for Lower Mantle Components, Thermals or Other ad hoc Adjustments</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Plate</span> tectonics introduces chemical,thermal,viscosity,melting and density inhomogeneities into the mantle and stress inhomogeneity into the <span class="hlt">plates</span>.Idealized models often assume uniform mantle, rigid homogeneous <span class="hlt">plates</span>,non-passive mantle, and ad hoc explanations for island chains, melting anomalies and <span class="hlt">continental</span> breakup. <span class="hlt">Plates</span>, however, drive and break themselves and organize the underlying mantle, in common with other cooled-from-above systems.Pressure, often ignored in simulations, suppresses thermal</p> <div class="credits"> <p class="dwt_author">D. L. Anderson; A. Meibom</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">249</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/7247662"> <span id="translatedtitle">Convergent <span class="hlt">plate</span> margin east of North Island, New Zealand</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Indian-Pacific <span class="hlt">plate</span> boundary passes along the eastern margin of North Island, New Zealand, with the Pacific <span class="hlt">plate</span> being thrust under the Indian <span class="hlt">plate</span> to the west. The <span class="hlt">continental</span> slope forming the Indian <span class="hlt">plate</span> margin is broad with a well-formed series of trench slope basins and intervening ridges along the <span class="hlt">continental</span> slope and shelf, subparallel to the margin, and continuing onto land. Multichannel seismic reflection data recorded across this margin show a thick (2.5-km) sedimentary section overlying oceanic basement in the deep-water part of the profile, and part of this sedimentary section is apparently being subducted under the accretionary prism. At the toe of the <span class="hlt">continental</span> slope, nascent thrusts, often showing little apparent offset but a change in reflection amplitude, occur over a broad region. Well-defined trench slope basins show several episodes of basin formation and thrusting and are similar to structural interpretations for adjacent onshore basins. A bottom simulating reflector, which may delineate a gas-hydrate layer, can be traced over the midslope part of the profile. A major reflector, interpreted as the base of the accretionary prism, can be traced discontinuously to the coast where it coincides with the top of a zone of high seismicity, considered to mark the top of the subducted Pacific <span class="hlt">plate</span>.</p> <div class="credits"> <p class="dwt_author">Davey, F.J; Hampton, M.; Lewis, K.</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-07-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">250</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.oceanexplorer.noaa.gov/explorations/02fire/background/education/media/ring_big_plates_5_6.pdf"> <span id="translatedtitle">The Biggest <span class="hlt">Plates</span> on Earth: <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">In this lesson, students investigate the movement of Earth's tectonic <span class="hlt">plates</span>, the results of these movements, and how magnetic anomalies present at spreading centers document the motion of the crust. As a result of this activity, students will be able to describe the motion of tectonic <span class="hlt">plates</span>, differentiate between three types of <span class="hlt">plate</span> boundaries, infer what type of boundary exists between two tectonic <span class="hlt">plates</span>, and understand how magnetic anomalies provide a record of geologic history and crustal motion around spreading centers. As an example, they will also describe <span class="hlt">plate</span> boundaries and tectonic activity in the vicinity of the Juan de Fuca <span class="hlt">plate</span> adjacent to the Pacific Northwest coast of North America.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">251</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/51244617"> <span id="translatedtitle">Intermittent <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Intermittent <span class="hlt">Plate</span> Tectonics A basic premise of Earth Science is that <span class="hlt">plate</span> tectonics has been continuously operating since it began early in Earth's history. Yet, <span class="hlt">plate</span>-tectonic theory itself, specifically the collisional phase of the Wilson Cycle, constitutes a process that is capable of stopping all <span class="hlt">plate</span> motion. The plausibility of a <span class="hlt">plate</span>-tectonic hiatus is most easily illustrated by considering the</p> <div class="credits"> <p class="dwt_author">P. G. Silver; M. D. Behn</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">252</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/48926915"> <span id="translatedtitle">Petrology and <span class="hlt">plate</span> tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Petrology played an important role in the formulation of <span class="hlt">plate</span> tectonics and early <span class="hlt">plate</span> tectonic interpretations of the geologic past. In the last few years widespread interest in <span class="hlt">plate</span> tectonics and progress in <span class="hlt">plate</span> tectonic interpretations have begun to give petrology various feedback effects.In the period 1971–1974 there were two symposiums intended particularly to connect petrology with <span class="hlt">plate</span> tectonics [Wyllie,</p> <div class="credits"> <p class="dwt_author">Akiho Miyashiro</p> <p class="dwt_publisher"></p> <p class="publishDate">1975-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">253</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/56543184"> <span id="translatedtitle">Caffeine does not cause <span class="hlt">override</span> of the G2\\/M block induced by UVc or gamma radiation in normal human skin fibroblasts</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Caffeine has for many years been known to be involved in the sensitization of DNA to damage. One potential mechanism recently put forward is an <span class="hlt">override</span> of the G2\\/M block induced by irradiation, which would leave the cells less time for DNA repair prior to mitosis. However, different cell types display a variety of responses and no clear pathway has</p> <div class="credits"> <p class="dwt_author">G Deplanque; F Vincent; M C M Mah-Becherel; J-P Cazenave; J-P Bergerat; C Klein-Soyer</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">254</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1994E%26PSL.126..143S"> <span id="translatedtitle"><span class="hlt">Plate</span>-scale potential-energy distributions and the fragmentation of ageing <span class="hlt">plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Geoid anomalies associated with mid-ocean ridge systems and a number of <span class="hlt">continental</span> margins imply that, on the scale of individual <span class="hlt">plates</span>, the old ocean lithosphere represents a gravitational potential energy sink. Since lateral variations in potential energy contribute to deviatoric stresses in the lithosphere, the changing potential-energy distributions in individual <span class="hlt">plates</span> associated with the growth and ageing of the oceanic lithosphere may be expected to result in changes in the intraplate stress field. Analytical models for simple <span class="hlt">plate</span> geometries using lithospheric density models consistent with small positive (+6 m) geoid anomalies across <span class="hlt">continental</span> margins show that the growth of oceanic lithospheric over a period of 200 Ma may contribute to a decline in the mean <span class="hlt">plate</span> potential energy bar-U(sub p) of about -1 x 10(exp 12) N/m and thus contribute a mean extensional stress difference (bar-sigma(sub zz) - bar-sigma(sub xx)) in <span class="hlt">continental</span> lithosphere of up to about 8 MPa (averaged over a 125 km thick lithosphere). These estimates are sensitive to the assumed mean <span class="hlt">continental</span> potential energy bar-U(sub c), about which there is some uncertainty. For higher bar-U(sub c), approaching that of the mid-ocean ridges (U(sub MOR)), the net decline in bar-U(sub p) may be as much as -1.7 x 10(exp 12) N/m, whereas for significantly lower bar-U(sub c), approaching that of old ocean lithosphere, <span class="hlt">plate</span> growth may increase bar-U(sub p) transiently by up to 2.7 x 10(exp 12) N/m, leading to compression in the continents. In the African and Antarctic <span class="hlt">plates</span> the ageing of the ocean lithosphere since the late Jurassic is estimated to have contributed to a decline in bar-U(sub p) of about -0.6 x 10(exp 12) and -0.95 x 10(exp 12) N/m respectively, contributing a mean stress difference of about 5 MPa and 7.5 MPa in the respective continents. The predicted stress changes associated with ageing of the oceanic lithosphere may provide an important contribution to the stress fields that eventually lead to the fragmentation of ageing <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Sandiford, Mike; Coblentz, David</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-08-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">255</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6720460"> <span id="translatedtitle">Development of transtensional and transpressive <span class="hlt">plate</span> boundaries due to noncircular (cycloid) relative <span class="hlt">plate</span> motion</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The trace of a transform fault commonly is assumed to be circular and concentric with the finite relative motion of the <span class="hlt">plates</span> adjacent to the fault. These assumptions have led to controversy as the transform fault label has been applied to the San Andreas fault in California because the San Andreas fault is neither circular nor concentric with the motion of the Pacific <span class="hlt">plate</span> relative to the North American <span class="hlt">plate</span>. The assumption of circular relative <span class="hlt">plate</span> motion over a finite time interval is not generally valid. When finite relative <span class="hlt">plate</span> motion is not circular, the length and orientation of a transform fault must change through time. The length and orientation of ridge-ridge transform faults in oceanic crust evolve through the migration, propagation, and abandonment of ridge segments. Transform faults that bound <span class="hlt">continental</span> crust evolve differently than do transform faults along mid-ocean ridges because <span class="hlt">continental</span> transform faults typically do not have ridges at both ends and because of the rheological differences between oceanic and <span class="hlt">continental</span> crust. Along continent-continent transform faults in which the initial displacement is entirely strike slip, later displacements will be progressively more divergent or convergent (i.e., transtensive or transpressive). Transtension can result in the development of deep basins with high heat flow. Transpression can result in folding, reverse faulting, and decoupling of the crust from its lower crustal or mantle lithosphere in the region adjacent to the transform fault. Regardless of whether the transform boundary becomes transtensional or transpressional, the boundary evolves from a discrete transform fault to a broader, structurally complex accommodation zone (sensu lato).</p> <div class="credits"> <p class="dwt_author">Cronin, V.S. (Univ. of Wisconsin, Milwaukee (USA))</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">256</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.U51D..02E"> <span id="translatedtitle">Subduction zone <span class="hlt">plate</span> bending earthquakes and implications for the hydration of the downgoing <span class="hlt">plate</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The greatest uncertainty in the amount of water input into the Earth at subduction zones results from poor constraints on the degree and depth extent of mantle serpentinization in the downgoing slab. The maximum depth of serpentinization is thought to be partly controlled by the maximum depth of tensional earthquakes in the outer rise and trench and is expected to vary from subduction zone to subduction zone or even along-strike for a single subduction zone. We explore the maximum depth of extensional faulting on the incoming <span class="hlt">plate</span> for various subduction zones in order to gain insight into the possible extent of slab serpentinization. We relocate trench events at island arc subduction zones using hypocentroidal decomposition to determine which earthquakes occurred within the incoming <span class="hlt">plate</span>. For earthquakes with Mw ~5.5+, we determine accurate depths and refine the CMT focal mechanism by inverting teleseismic P and SH waveforms. Results from the Mariana outer rise indicate that extensional earthquakes occur in the Pacific <span class="hlt">plate</span> at depths ranging from 10-20 km beneath the top of the crust, with the character of trench seismicity changing significantly between the northern and southern portions of the subduction zone. In comparision, results from the Aleutian subduction zone show extensional trench earthquakes occurring from 5-30 km below the surface of the subducting slab. Compressional incoming <span class="hlt">plate</span> earthquakes occur only near the Alaskan Peninsula, possibly due to stronger coupling between the slab and <span class="hlt">overriding</span> <span class="hlt">plate</span> in this region. Further results from oceanic arc subduction zones will be presented and differences between subduction zones as well as along-strike differences in the character of trench seismicity will be highlighted. If the presence of extensional faulting indicates subducting lithosphere hydration, then we expect that as much as the top 30 km of the slab may be hydrated and that the degree of slab serpentinization may vary significantly between subduction zones, potentially affecting arc geochemistry, intermediate depth seismicity, and the subduction zone water budget.</p> <div class="credits"> <p class="dwt_author">Emry, E. L.; Wiens, D. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">257</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://learningcenter.nsta.org/product_detail.aspx?id=10.2505/7/SCB-PT.4.1"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: Consequences of <span class="hlt">Plate</span> Interactions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This Science Object is the fourth of five Science Objects in the <span class="hlt">Plate</span> Tectonic SciPack. It identifies the events that may occur and landscapes that form as a result of different <span class="hlt">plate</span> interactions. The areas along <span class="hlt">plate</span> margins are active. <span class="hlt">Plates</span> pushing against one another can cause earthquakes, volcanoes, mountain formation, and very deep ocean trenches. <span class="hlt">Plates</span> pulling apart from one another can cause smaller earthquakes, magma rising to the surface, volcanoes, and oceanic valleys and mountains from sea-floor spreading. <span class="hlt">Plates</span> sliding past one another can cause earthquakes and rock deformation. Learning Outcomes:� Explain why volcanoes and earthquakes occur along <span class="hlt">plate</span> boundaries. � Explain how new sea floor is created and destroyed.� Describe features that may be seen on the surface as a result of <span class="hlt">plate</span> interactions.</p> <div class="credits"> <p class="dwt_author">National Science Teachers Association (NSTA)</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-11-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">258</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2003JGRB..108.2328A"> <span id="translatedtitle">Seismic imaging of a convergent <span class="hlt">continental</span> margin and plateau in the central Andes (Andean <span class="hlt">Continental</span> Research Project 1996 (ANCORP'96))</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A 400-km-long seismic reflection profile (Andean <span class="hlt">Continental</span> Research Project 1996 (ANCORP'96)) and integrated geophysical experiments (wide-angle seismology, passive seismology, gravity, and magnetotelluric depth sounding) across the central Andes (21°S) observed subduction of the Nazca <span class="hlt">plate</span> under the South American continent. An east dipping reflector (Nazca Reflector) is linked to the down going oceanic crust and shows increasing downdip intensity before gradual breakdown below 80 km. We interpret parts of the Nazca Reflector as a fluid trap located at the front of recent hydration and shearing of the mantle, the fluids being supplied by dehydration of the oceanic <span class="hlt">plate</span>. Patches of bright (Quebrada Blanca Bright Spot) to more diffuse reflectivity underlie the plateau domain at 15-30 km depth. This reflectivity is associated with a low-velocity zone, P to S wave conversions, the upper limits of high conductivity and high V p /V s ratios, and to the occurrence of Neogene volcanic rocks at surface. We interpret this feature as evidence of widespread partial melting of the plateau crust causing decoupling of the upper and lower crust during Neogene shortening and plateau growth. The imaging properties of the <span class="hlt">continental</span> Moho beneath the Andes indicate a broad transitional character of the crust-mantle boundary owing to active processes like hydration of mantle rocks (in the cooler parts of the <span class="hlt">plate</span> margin system), magmatic underplating and intraplating under and into the lowermost crust, mechanical instability at Moho, etc. Hence all first-order features appear to be related to fluid-assisted processes in a subduction setting.</p> <div class="credits"> <p class="dwt_author">ANCORP Working Group,</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-07-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">259</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2002EGSGA..27.6298B"> <span id="translatedtitle">Dynamic <span class="hlt">Plate</span> Boundaries and Restored Synthetic Isochrons: The Indispensable Tools To Constrain <span class="hlt">Plate</span> Tectonic Models</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We developed a <span class="hlt">plate</span> tectonics model for the Paleozoic and Mesozoic (Ordovician to Cretaceous) integrating dynamic <span class="hlt">plate</span> boundaries, <span class="hlt">plate</span> buoyancy, ocean-spreading rates and major tectonic and magmatic events. <span class="hlt">Plates</span> have been constructed through time by adding/removing oceanic material symbolized by syntethic isochrones, to ma- jor continents and terranes. These oceanic isochrons have been constructed through time in order to define the location of the spreading ridges and to restore subducted ocean basins. To simplify the process we worked with a symmetrical sea floor spread- ing for the main oceans (Paleo- and NeoTethys). Driving forces like slab pull and slab buoyancy were used to constrain the evolution of paleo-oceanic domains. This ap- proach offers a good control on the sea floor spreading and <span class="hlt">plate</span> kinematics. This new method represents a distinct departure from classical <span class="hlt">continental</span> drift reconstructions, which are not constrained due to the lack of <span class="hlt">plate</span> boundaries. This model allows a more comprehensive analysis of the development of the Tethyan realm in space and time. In particular, the relationship between the Variscan and the Cimmerian cycles in the Mediterranean-Alpine realm is clearly illustrated by numerous maps. For the Alpine cycle, the relationship between the Alpides senso stricto and the Tethysides is also explicable in terms of <span class="hlt">plate</span> tectonic development of the Alpine Tethys-Atlantic domain versus the NeoTethys domain.</p> <div class="credits"> <p class="dwt_author">Borel, G. D.; Stampfli, G. M.</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">260</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011GGG....12.5S32H"> <span id="translatedtitle">Submarine slope failures along the convergent <span class="hlt">continental</span> margin of the Middle America Trench</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We present the first comprehensive study of mass wasting processes in the <span class="hlt">continental</span> slope of a convergent margin of a subduction zone where tectonic processes are dominated by subduction erosion. We have used multibeam bathymetry along ˜1300 km of the Middle America Trench of the Central America Subduction Zone and deep-towed side-scan sonar data. We found abundant evidence of large-scale slope failures that were mostly previously unmapped. The features are classified into a variety of slope failure types, creating an inventory of 147 slope failure structures. Their type distribution and abundance define a segmentation of the <span class="hlt">continental</span> slope in six sectors. The segmentation in slope stability processes does not appear to be related to slope preconditioning due to changes in physical properties of sediment, presence/absence of gas hydrates, or apparent changes in the hydrogeological system. The segmentation appears to be better explained by changes in slope preconditioning due to variations in tectonic processes. The region is an optimal setting to study how tectonic processes related to variations in intensity of subduction erosion and changes in relief of the underthrusting <span class="hlt">plate</span> affect mass wasting processes of the <span class="hlt">continental</span> slope. The largest slope failures occur offshore Costa Rica. There, subducting ridges and seamounts produce failures with up to hundreds of meters high headwalls, with detachment planes that penetrate deep into the <span class="hlt">continental</span> margin, in some cases reaching the <span class="hlt">plate</span> boundary. Offshore northern Costa Rica a smooth oceanic seafloor underthrusts the least disturbed <span class="hlt">continental</span> slope. Offshore Nicaragua, the ocean <span class="hlt">plate</span> is ornamented with smaller seamounts and horst and graben topography of variable intensity. Here mass wasting structures are numerous and comparatively smaller, but when combined, they affect a large part of the margin segment. Farther north, offshore El Salvador and Guatemala the downgoing <span class="hlt">plate</span> has no large seamounts but well-defined horst and graben topography. Off El Salvador slope failure is least developed and mainly occurs in the uppermost <span class="hlt">continental</span> slope at canyon walls. Off Guatemala mass wasting is abundant and possibly related to normal faulting across the slope. Collapse in the wake of subducting ocean <span class="hlt">plate</span> topography is a likely failure trigger of slumps. Rapid oversteepening above subducting relief may trigger translational slides in the middle Nicaraguan upper Costa Rican slope. Earthquake shaking may be a trigger, but we interpret that slope failure rate is lower than recurrence time of large earthquakes in the region. Generally, our analysis indicates that the importance of mass wasting processes in the evolution of margins dominated by subduction erosion and its role in sediment dynamics may have been previously underestimated.</p> <div class="credits"> <p class="dwt_author">Harders, Rieka; Ranero, CéSar R.; Weinrebe, Wilhelm; Behrmann, Jan H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-06-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_12");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a style="font-weight: bold;">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_14");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_13 div --> <div id="page_14" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_13");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a style="font-weight: bold;">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_15");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">261</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40848441"> <span id="translatedtitle"><span class="hlt">Continental</span> rifting parallel to ancient collisional belts: an effect of the mechanical anisotropy of the lithospheric mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Analysis of major rift systems suggests that the preexisting structure of the lithosphere is a key parameter in the rifting process. Rift propagation is not random, but tends to follow the trend of the orogenic fabric of the <span class="hlt">plates</span>, systematically reactivating ancient lithospheric structures. <span class="hlt">Continental</span> rifts often display a clear component of strike–slip deformation, in particular in the early rifting</p> <div class="credits"> <p class="dwt_author">Andréa Tommasi; Alain Vauchez</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">262</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.dstu.univ-montp2.fr/PERSO/tommasi/tommasi_vauchez_2001.pdf"> <span id="translatedtitle"><span class="hlt">Continental</span> rifting parallel to ancient collisional belts: an e¡ect of the mechanical anisotropy of the lithospheric mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Analysis of major rift systems suggests that the preexisting structure of the lithosphere is a key parameter in the rifting process. Rift propagation is not random, but tends to follow the trend of the orogenic fabric of the <span class="hlt">plates</span>, systematically reactivating ancient lithospheric structures. <span class="hlt">Continental</span> rifts often display a clear component of strike^ slip deformation, in particular in the early</p> <div class="credits"> <p class="dwt_author">Andrea Tommasi; Alain Vauchez</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">263</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18075591"> <span id="translatedtitle">Dynamics of Mid-Palaeocene North Atlantic rifting linked with European intra-<span class="hlt">plate</span> deformations.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">The process of <span class="hlt">continental</span> break-up provides a large-scale experiment that can be used to test causal relations between <span class="hlt">plate</span> tectonics and the dynamics of the Earth's deep mantle. Detailed diagnostic information on the timing and dynamics of such events, which are not resolved by <span class="hlt">plate</span> kinematic reconstructions, can be obtained from the response of the interior of adjacent <span class="hlt">continental</span> <span class="hlt">plates</span> to stress changes generated by <span class="hlt">plate</span> boundary processes. Here we demonstrate a causal relationship between North Atlantic <span class="hlt">continental</span> rifting at approximately 62 Myr ago and an abrupt change of the intra-<span class="hlt">plate</span> deformation style in the adjacent European continent. The rifting involved a left-lateral displacement between the North American-Greenland <span class="hlt">plate</span> and Eurasia, which initiated the observed pause in the relative convergence of Europe and Africa. The associated stress change in the European continent was significant and explains the sudden termination of a approximately 20-Myr-long contractional intra-<span class="hlt">plate</span> deformation within Europe, during the late Cretaceous period to the earliest Palaeocene epoch, which was replaced by low-amplitude intra-<span class="hlt">plate</span> stress-relaxation features. The pre-rupture tectonic stress was large enough to have been responsible for precipitating <span class="hlt">continental</span> break-up, so there is no need to invoke a thermal mantle plume as a driving mechanism. The model explains the simultaneous timing of several diverse geological events, and shows how the intra-<span class="hlt">continental</span> stratigraphic record can reveal the timing and dynamics of stress changes, which cannot be resolved by reconstructions based only on <span class="hlt">plate</span> kinematics. PMID:18075591</p> <div class="credits"> <p class="dwt_author">Nielsen, Søren B; Stephenson, Randell; Thomsen, Erik</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-12-13</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">264</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1984JGR....89.7753K"> <span id="translatedtitle">Florida: A Jurassic transform <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Magnetic, gravity, seismic, and deep drill hole data integrated with <span class="hlt">plate</span> tectonic reconstructions substantiate the existence of a transform <span class="hlt">plate</span> boundary across southern Florida during the Jurassic. On the basis of this integrated suite of data the pre-Cretaceous Florida-Bahamas region can be divided into the pre-Jurassic North American <span class="hlt">plate</span>, Jurassic marginal rift basins, and a broad Jurassic transform zone including stranded blocks of pre-Mesozoic <span class="hlt">continental</span> crust. Major tectonic units include the Suwannee basin in northern Florida containing Paleozoic sedimentary rocks, a central Florida basement complex of Paleozoic age crystalline rock, the west Florida platform composed of stranded blocks of <span class="hlt">continental</span> crust, the south Georgia rift containing Triassic sedimentary rocks which overlie block-faulted Suwannee basin sedimentary rocks, the Late Triassic-Jurassic age Apalachicola rift basin, and the Jurassic age south Florida, Bahamas, and Blake Plateau marginal rift basins. The major tectonic units are bounded by basement hinge zones and fracture zones (FZ). The basement hinge zone represents the block-faulted edge of the North American <span class="hlt">plate</span>, separating Paleozoic and older crustal rocks from Jurassic rifted crust beneath the marginal basins. Fracture zones separate Mesozoic marginal sedimentary basins and include the Blake Spur FZ, Jacksonville FZ, Bahamas FZ, and Cuba FZ, bounding the Blake Plateau, Bahamas, south Florida, and southeastern Gulf of Mexico basins. The Bahamas FZ is the most important of all these features because its northwest extension coincides with the Gulf basin marginal fault zone, forming the southern edge of the North American <span class="hlt">plate</span> during the Jurassic. The limited space between the North American and the South American/African <span class="hlt">plates</span> requires that the Jurassic transform zone, connecting the Central Atlantic and the Gulf of Mexico spreading systems, was located between the Bahamas and Cuba FZ's in the region of southern Florida. Our <span class="hlt">plate</span> reconstructions combined with chronostratigraphic and lithostratigraphic information for the Gulf of Mexico, southern Florida, and the Bahamas indicate that the gulf was sealed off from the Atlantic waters until Callovian time by an elevated Florida-Bahamas region. Restricted influx of waters started in Callovian as a <span class="hlt">plate</span> reorganization, and increased <span class="hlt">plate</span> separation between North America and South America/Africa produced waterways into the Gulf of Mexico from the Pacific and possibly from the Atlantic.</p> <div class="credits"> <p class="dwt_author">Klitgord, Kim D.; Popenoe, Peter; Schouten, Hans</p> <p class="dwt_publisher"></p> <p class="publishDate">1984-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">265</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5964066"> <span id="translatedtitle">Neogene rotations and quasicontinuous deformation of the Pacific Northwest <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Paleomagnetically determined rotations about vertical axes of 15 to 12 Ma flows of the Miocene Columbia River Basalt Group of Oregon and Washington decrease smoothly with distance from the <span class="hlt">plate</span> margin, consistent with a simple physical model for <span class="hlt">continental</span> deformation that assumes the lithosphere behaves as a thin layer of fluid. The average rate of northward translation of the <span class="hlt">continental</span> margin since 15 Ma calculated from the rotations, using this model, is about 15 mm/year, which suggests that much of the tangential motion between the Juan de Fuca and North American <span class="hlt">plates</span> since middle Miocene time has been taken up by deformation of North America. The fluid-like character of the large-scale deformation implies that the brittle upper crust follows the motions of the deeper parts of the lithosphere.</p> <div class="credits"> <p class="dwt_author">England, P. (Oxford Univ. (England)); Wells, R.E. (Geological Survey, Menlo Park, CA (United States))</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">266</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14837654"> <span id="translatedtitle"><span class="hlt">Continental</span> volume and freeboard through geological time</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The consequences of approximately constant freeboard for <span class="hlt">continental</span> growth are explored using a model that relates the volumes of isostatically compensated continents and oceans to the secular decline in terrestrial heat flow. It is found that a post-Archean increase in freeboard by 200 m requires <span class="hlt">continental</span> growth of only 10 percent, while a decrease in freeboard by 200 m during</p> <div class="credits"> <p class="dwt_author">G. Schubert; A. P. S. Reymer</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">267</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/2891638"> <span id="translatedtitle"><span class="hlt">Continental</span> delamination and the Colorado Plateau</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Continental</span> lithosphere is in unstable mechanical equilibrium because its mantle layer is denser than the asthenosphere. If any process such as cracking, slumping, or plume erosion intially provide an elongated conduit connecting the underlying asthenosphere with the base of the <span class="hlt">continental</span> crust, the dense lithespheric boundary layer could peel away from the crust and sink. An analytic model for sinking</p> <div class="credits"> <p class="dwt_author">Peter Bird</p> <p class="dwt_publisher"></p> <p class="publishDate">1979-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">268</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/41005054"> <span id="translatedtitle">Pleistocene chronology of <span class="hlt">continental</span> margin sedimentation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Commonly accepted models for the evolution of <span class="hlt">continental</span> margins link sediment erosion, transport and deposition to eustasy. To test these models, we constructed an oxygen isotope record from 520 m of Pleistocene sediment recovered by the Ocean Drilling Program Leg 174A from the New Jersey <span class="hlt">continental</span> slope. The ?18O record was calibrated to SPECMAP oxygen isotope time scale [Imbrie et</p> <div class="credits"> <p class="dwt_author">Cecilia M. G McHugh; Hilary Clement Olson</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">269</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/41396853"> <span id="translatedtitle">Accretionary Orogenesis in the Active <span class="hlt">Continental</span> Margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This paper reviews the research history and progress in the study of accretionary orogenesis, and concludes that accretionary orogenesis is the fundamental process of <span class="hlt">continental</span> evolution throughout Earth's history. According to the authors' point of view, the formation and evolution of orogenic belts can be explained by the evolution of composite island arc-basin systems along active <span class="hlt">continental</span> margins. The formation</p> <div class="credits"> <p class="dwt_author">Sihua YUAN; Guitang PAN; Liquan WANG; Xinsheng JIANG; Fuguang YIN; Wanping ZHANG; Jiewen ZHUO</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">270</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFMOS41A..06M"> <span id="translatedtitle">Warm-water flow above deep water methane hydrates at an Arctic <span class="hlt">continental</span> margin - A view on climate impacts</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We detected geophysical evidence for the base of the gas hydrate stability zone (GHSZ) in form of a bottom simulating reflector (BSR) at mid slope of the <span class="hlt">continental</span> margin of NW-Svalbard and collected acoustic and video-footage evidence for major methane release at the shelf (flares). Flares are acoustic expressions of methane bubbles emanating from the seabed. Warming of upper ocean water masses that impinge on sediments of the upper <span class="hlt">continental</span> slope may reduce the methane hydrate stability zone. As a result, it can cause melting of gas hydrates, overpressure build up, abrupt releases of methane from the seabed, and geohazards. However, the warm-water core of the W-Spitsbergen current does not intercept with the <span class="hlt">continental</span> slope (July 2009). There is also no evidence for a BSR pinch out on the upper <span class="hlt">continental</span> slope. Accordingly, warming of the W-Spitsbergen current at this location may have less or no effects on the release of methane from the seabed by reducing the GHSZ. Alternatively, fluids may be released by reactivation of faults due to seismic activity (< 7 magnitude) around Svalbard. Earthquakes occur frequently along the divergent <span class="hlt">plate</span> boundary and the nearby <span class="hlt">continental</span>-ocean boundary (COB) of the W-Svalbard <span class="hlt">continental</span> margin. We therefore consider two major ways to release fluids: 1) an upward migration of free gas beneath the GHSZ towards the projected outcrop zone at the upper <span class="hlt">continental</span> margin, and/ or 2) a migration and release of methane at active fault zones.</p> <div class="credits"> <p class="dwt_author">Mienert, J.; Bünz, S.; Greinert, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">271</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40168855"> <span id="translatedtitle">Numerical modeling of the development of southeastern Red Sea <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The Red Sea <span class="hlt">continental</span> margin (RSCM) corresponds to a wide hinge zone between Red Sea and Arabian <span class="hlt">plate</span>. This margin has\\u000a been studied through geological and geophysical observations primarily in regard to the evolution of Red Sea rift. This margin\\u000a is characterized by occurrence of thin sediments, significant onshore uplift, tectonic subsidence of the offshore sedimentary\\u000a basin, active faulting and</p> <div class="credits"> <p class="dwt_author">Sunil Kumar Dwivedi; Daigoro Hayashi</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">272</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54391880"> <span id="translatedtitle">Lithospheric deformation during <span class="hlt">continental</span> collision acrossSouth Island, New Zealand: Reconciling numerical modeling with observation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The young <span class="hlt">continental</span> <span class="hlt">plate</span> collision at South Island, New Zealand represents a useful location for studying the dynamics of an active orogen. The region has been the focus of a number of modeling studies and various geological\\/geophysical\\/geodetic observations provide important constraints on its evolution. However, the fundamental nature of deformation of the sub-crustal lithosphere (i.e., mantle lithosphere) during the collision</p> <div class="credits"> <p class="dwt_author">R. N. Pysklywec; C. Beaumont</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">273</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.9701A"> <span id="translatedtitle">Thermal regime of <span class="hlt">continental</span> subduction: the record from exhumed HP-LT terranes (New Caledonia, Oman, Corsica)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Unlike the thermal regimes of present-day subduction or collision zones, the variety of possible thermal evolutions accompanying the transient stage of <span class="hlt">continental</span> subduction (i.e., the shift from oceanic subduction to <span class="hlt">continental</span> collision) remains poorly known. We herein show that the thermal regime of <span class="hlt">continental</span> subduction can be confidently retrieved from three well-documented fossil settings (i.e., from high-pressure low temperature <span class="hlt">continental</span> material from Oman, New Caledonia, Corsica) that were not modified by later collision or a later metamorphic imprint. We primarily focus on their thermal structures (derived from estimates of maximum temperatures, P-T data and age constraints) and overall tectonic organization. For the sake of comparison, new petrological investigations were performed on the metamorphic architecture of northern New Caledonia (Pam Peninsula) and are presented here. We show that the overall structure and metamorphic patterns of these three HP belts derived from <span class="hlt">continental</span> subduction evidence striking similarities. In particular, the inferred thermal regime of <span class="hlt">continental</span> subduction appears largely independent from the initial geodynamic setting (i.e., from the initial thermal regime of oceanic subduction, the nature of the incoming <span class="hlt">plate</span> or of the upper <span class="hlt">plate</span>). This suggests that <span class="hlt">continental</span> cover units subducted over a short time period represent cold underplated material that buffers the subduction thermal regime, whatever the exact structure, nature, or thermal state of incoming material. Similarities in the type, size and P-T conditions of the various tectonic units and in the overall tectonic organization point to specific accretionary-type subduction dynamics, yet to differences in mechanical coupling between the three case studies. Our study thereby provides constraints on exhumation dynamics and models of <span class="hlt">continental</span> subduction</p> <div class="credits"> <p class="dwt_author">Agard, Philippe; Vitale-Brovarone, Alberto</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">274</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFMOS14A..05M"> <span id="translatedtitle">Geomorphology of <span class="hlt">continental</span> slope canyons</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Work on the US Atlantic slope reveals some remarkably analogous geomorphological properties to subaerial surfaces. Although the processes creating and modifying submarine slopes are different to those affecting landscapes above sea level, these geometrical similarities suggest that it may become possible to model slope evolution by analogous methods to those in subaerial geomorphology. Canyons in <span class="hlt">continental</span> slopes, for example, can have similar "concavity" to bedrock eroding rivers (upwards-curved longitudinal profiles), tributaries can join main channels at confluences with smoothly converging elevations (obeying Playfair's Law), and tributaries with smaller contributing area tend to be steeper than their associated principal channels. Knickpoints in channels of tectonically active slopes also show fluvial-like tendencies, for example, there is evidence that they can advect up-stream or smooth out like in alluvial channels. Based on these observations, work has concentrated on assessing whether the "flow power" erosion models of fluvial geomorphology can be adapted to model submarine canyons. Other features of the Atlantic slope canyons can also be analogous to subaerial systems, for example, inter-canyon ridges can be sharp where bounded by steep, linear hillslopes analogous to threshold slopes on land. Many weakly incised areas of the uppermost <span class="hlt">continental</span> slope in the USA Atlantic are smooth and upwards-convex between channels, much like in diffusive lowland landscapes. While some of this correspondence is fortuitous, the gravity effect on saltating sand may produce a down- slope movement proportional to local bed gradient that leads to a diffusive-like evolution of the surface topography in some circumstances.</p> <div class="credits"> <p class="dwt_author">Mitchell, N. C.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">275</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/10706738"> <span id="translatedtitle">Genetic analysis of the influence of pertussis toxin on experimental allergic encephalomyelitis susceptibility: an environmental agent can <span class="hlt">override</span> genetic checkpoints.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Pertussis toxin (PTX) is a potent ancillary adjuvant used to elicit several different autoimmune diseases, including experimental allergic encephalomyelitis (EAE). To delineate the genetics of PTX effect in EAE, we mapped EAE-modifying (eae-m) loci in cohorts of backcross mice immunized with and without PTX. In this study, we analyzed the genetic basis of EAE susceptibility and severity and the intermediate phenotypes of mononuclear cell infiltration, suppuration, and demyelination. In animals immunized with PTX, one major locus, eae9, controls disease susceptibility and severity. Eae9 also regulates the extent of mononuclear cell infiltration of the spinal cord in male mice. Without PTX, five eae-m loci were noted, including three new loci in intervals on chromosomes 8 (eae14), 10 (eae17), and 18 (eae18). Taken together, these results suggest that eae9 controls the effects of PTX in EAE susceptibility, and is capable of <span class="hlt">overriding</span> the other genetic checkpoints in the pathogenesis of this disease. PMID:10706738</p> <div class="credits"> <p class="dwt_author">Blankenhorn, E P; Butterfield, R J; Rigby, R; Cort, L; Giambrone, D; McDermott, P; McEntee, K; Solowski, N; Meeker, N D; Zachary, J F; Doerge, R W; Teuscher, C</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-03-15</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">276</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2121000"> <span id="translatedtitle">The hnRNP C proteins contain a nuclear retention sequence that can <span class="hlt">override</span> nuclear export signals</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">Nascent pre-mRNAs associate with the abundant heterogeneous nuclear RNP (hnRNP) proteins and remain associated with them throughout the time they are in the nucleus. The hnRNP proteins can be divided into two groups according to their nucleocytoplasmic transport properties. One group is completely restricted to the nucleus in interphase cells, whereas the other group, although primarily nuclear at steady state, shuttles between the nucleus and the cytoplasm. Nuclear export of the shuttling hnRNP proteins is mediated by nuclear export signals (NESs). Mounting evidence indicates that NES-bearing hnRNP proteins are mediators of mRNA export. The hnRNP C proteins are representative of the nonshuttling group of hnRNP proteins. Here we show that hnRNP C proteins are restricted to the nucleus not because they lack an NES, but because they bear a nuclear retention sequence (NRS) that is capable of <span class="hlt">overriding</span> NESs. The NRS comprises approximately 78 amino acids and is largely within the auxiliary domain of hnRNP C1. We suggest that the removal of NRS-containing hnRNP proteins from pre- mRNA/mRNA is required for mRNA export from the nucleus and is an essential step in the pathway of gene expression.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1996-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">277</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5879991"> <span id="translatedtitle">Computer animation of Phanerozoic <span class="hlt">plate</span> motions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Since 1985, the PALEOMAP Project, in collaboration with research groups both in the US and abroad, has assembled a digital model that describes global <span class="hlt">plate</span> motions during the last 600 million years. In this paper the authors present a series of computer animations that dynamically illustrates the movement of continents and terranes, and the evolution of the ocean basins since the breakup of the late Precambrian supercontinent. These animations depict the motion of the <span class="hlt">plates</span> from both equatorial and polar perspectives. Mesozoic and Cenozoic <span class="hlt">plate</span> tectonic reconstructions are based on a synthesis of linear magnetic anomalies, fracture zone locations, intracontinental rifts, collision and thrust belts, and zones of strike-slip. Paleozoic <span class="hlt">plate</span> reconstructions, though more speculative, are based on evidence of past subduction, <span class="hlt">continental</span> collision, and inferred sea floor spreading. The relative longitudinal positions of the continents during the Paleozoic and the width of intervening oceans have been adjusted to best explain changing biogeographic and paleoclimatic patterns. A new paleomagnetic/hot spot reference frame has been constructed that combines paleomagnetic data compiled by Rob Van der Voo (1992) with inferred motion relative to a fixed frame of hot spots. Using probable Early Mesozoic and Paleozoic hot spot tracks on the major continents, the authors have extended <span class="hlt">plate</span> motions relative to the hot spot reference frame back to 400 million years.</p> <div class="credits"> <p class="dwt_author">Scotese, C.R. (Univ. of Texas, Arlington, TX (United States). Dept. of Geology)</p> <p class="dwt_publisher"></p> <p class="publishDate">1992-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">278</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/49295365"> <span id="translatedtitle">Mesozoic accretion of juvenile sub-<span class="hlt">continental</span> lithospheric mantle beneath South China and its implications: Geochemical and Re–Os isotopic results from Ningyuan mantle xenoliths</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The mechanism for the widespread Mesozoic magmatism in South China has been ascribed to either the paleo-Pacific <span class="hlt">plate</span> subduction or intra-<span class="hlt">continental</span> lithospheric extension. Mantle xenoliths entrained in the Jurassic Ningyuan alkaline basalts from southern Hunan Province, including twelve lherzolites and one harzburgite, have been studied to constrain the composition and age of the Mesozoic sub-<span class="hlt">continental</span> lithospheric mantle. The lherzolites contain</p> <div class="credits"> <p class="dwt_author">Chuan-Zhou Liu; Zhi-Chao Liu; Fu-Yuan Wu; Zhu-Yin Chu</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">279</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.abdn.ac.uk/~wpg008/Draut_etal_Tyrone_2009.pdf"> <span id="translatedtitle">Arc-continent collision and the formation of <span class="hlt">continental</span> crust: a new geochemical and isotopic record from the Ordovician Tyrone Igneous Complex, Ireland</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Collisions between oceanic island-arc terranes and passive <span class="hlt">continental</span> margins are thought to have been important in the formation of <span class="hlt">continental</span> crust throughout much of Earth's history. Magmatic evolution during this stage of the <span class="hlt">plate</span>-tectonic cycle is evident in several areas of the Ordovician Grampian-Taconic orogen, as we demonstrate in the first detailed geochemical study of the Tyrone Igneous Complex, Ireland.</p> <div class="credits"> <p class="dwt_author">AMY E. D RAUT; P ETER; D. C LIFT; J EFFREY; M. A MA; J ERZY</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">280</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.as.uky.edu/academics/departments_programs/EarthEnvironmentalSciences/EarthEnvironmentalSciences/Educational%20Materials/Documents/elearning/module04swf.swf"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics Animation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary"><span class="hlt">Plate</span> tectonics describes the behavior of Earth's outer shell, with pieces (<span class="hlt">plates</span>) bumping and grinding and jostling each other about. Explore these maps and animations to get a jump start on understanding <span class="hlt">plate</span> tectonic processes, history, and how motion of the <span class="hlt">plates</span> affects our planet today.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_13");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a style="font-weight: bold;">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_15");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_14 div --> <div id="page_15" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_14");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a style="font-weight: bold;">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_16");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">281</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60127246"> <span id="translatedtitle">CALUTRON FACE <span class="hlt">PLATE</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The construction of a removable cover <span class="hlt">plate</span> for a calutron tank is ; described. The <span class="hlt">plate</span> is fabricated of a rectangular frame member to which is ; welded a bowed or dished <span class="hlt">plate</span> of thin steel, reinforced with transverse ; stiffening ribs. When the tank is placed between the poles of a magnet, the ; <span class="hlt">plate</span> may be pivoted away</p> <div class="credits"> <p class="dwt_author">Brobeck</p> <p class="dwt_publisher"></p> <p class="publishDate">1959-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">282</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/46561010"> <span id="translatedtitle">Stiffened <span class="hlt">plates</span> in bending</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A semianalytical method developed by the author for the analysis of bare <span class="hlt">plates</span> has been extended to the static analysis of stiffened <span class="hlt">plates</span>. Both concentric and eccentric stiffeners have been considered. Deposition of the stiffener eccentric to the <span class="hlt">plate</span> gives rise to axial and bending displacements in the middle plane of the <span class="hlt">plate</span>. Three coupled differential equations are resulted due</p> <div class="credits"> <p class="dwt_author">M. Mukhopadhyay</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">283</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6456454"> <span id="translatedtitle">Tectonic structure and evolution of the Atlantic <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Atlantic <span class="hlt">continental</span> margin developed across the boundary between <span class="hlt">continental</span> and oceanic crust as rifting and then sea-floor spreading broke apart and separated the North American and African <span class="hlt">plates</span>, forming the Atlantic Ocean Basin. <span class="hlt">Continental</span> rifting began in Late Triassic with reactivation of Paleozoic thrust faults as normal faults and with extension across a broad zone of subparallel rift basins. Extension became localized in Early to Middle Jurassic along the zone that now underlies the large marginal basins, and other rift zones, such as the Newark, Hartford, and Fundy basins, were abandoned. Rifting and crustal stretching between the two continents gave way to sea-floor spreading Middle Jurassic and the formation of oceanic crust. This tectonic evolution resulted in formation of distinctive structural features. The marginal basins are underlain by a thinner crust and contain a variety of fault-controlled structures, including half-grabens, seaward- and landward-tilted blocks, faults that die out within the crust, and faults that penetrate the entire crust. This variable structure probably resulted from the late Triassic-Early Jurassic pattern of normal, listric, and antithetic faults that evolved from the Paleozoic thrust fault geometry. The boundary between marginal basins and oceanic crust is marked approximately by the East Coast Magnetic Anomaly (ECMA). A major basement fault is located in the Baltimore Canyon trough at the landward edge of the ECMA and a zone of seaward dipping reflectors is found just seaward of the ECMA off Georges Bank. The fracture zone pattern in Mesozoic oceanic crust can be traced landward to the ECMA.</p> <div class="credits"> <p class="dwt_author">Klitgord, K.D.; Schouten, H.; Hutchinson, D.R.</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">284</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFMOS21A1143T"> <span id="translatedtitle">Study of southern CHAONAN sag lower <span class="hlt">continental</span> slope basin deposition character in Northern South China Sea</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Northern South China Sea Margin locates in Eurasian <span class="hlt">plate</span>,Indian-Australia <span class="hlt">plate</span>,Pacific <span class="hlt">Plates</span>.The South China Sea had underwent a complicated tectonic evolution in Cenozoic.During rifting,the <span class="hlt">continental</span> shelf and slope forms a series of Cenozoic sedimentary basins,including Qiongdongnan basin,Pearl River Mouth basin,Taixinan basin.These basins fill in thick Cenozoic fluviolacustrine facies,transitional facies,marine facies,abyssal facies sediment,recording the evolution history of South China Sea Margin rifting and ocean basin extending.The studies of tectonics and deposition of depression in the Southern Chaonan Sag of lower <span class="hlt">continental</span> slope in the Norther South China Sea were dealt with,based on the sequence stratigraphy and depositional facies interpretation of seismic profiles acquired by cruises of“China and Germany Joint Study on Marine Geosciences in the South China Sea”and“The formation,evolution and key issues of important resources in China marginal sea",and combining with ODP 1148 cole and LW33-1-1 well.The free-air gravity anomaly of the break up of the <span class="hlt">continental</span> and ocean appears comparatively low negative anomaly traps which extended in EW,it is the reflection of passive margin gravitational effect.Bouguer gravity anomaly is comparatively low which is gradient zone extended NE-SW.Magnetic anomaly lies in Magnetic Quiet Zone at the Northern <span class="hlt">Continental</span> Margin of the South China Sea.The Cenozoic sediments of lower <span class="hlt">continental</span> slope in Southern Chaonan Sag can be divided into five stratum interface:SB5.5,SB10.5,SB16.5,SB23.8 and Hg,their ages are of Pliocene-Quaternary,late Miocene,middle Miocene,early Miocene,paleogene.The tectonic evolution of low <span class="hlt">continental</span> slope depressions can be divided into rifting,rifting-depression transitional and depression stages,while their depositional environments change from river to shallow marine and abyssa1,which results in different topography in different stages.The topographic evolvement in the study area includes three stages,that is Eogene,middle stage of lately Oligocene to early Miocene and middle Miocene to Present.Result shows that there are a good association of petroleum source rocks,reservoir rocks and seal rocks and structural traps in the Cenozoic and Mesozoic strata,as well as good conditions for the generation-migration-accumulation-preservation of petroleum in the lower continatal slope of Southern Chaoshan Sag.So the region has good petroleum prospect. Key words:Northern South China Sea;Chaoshan Sag; lower <span class="hlt">continental</span> slope; deposition.</p> <div class="credits"> <p class="dwt_author">Tang, Y.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">285</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/geodesy/activities/41187.html"> <span id="translatedtitle">Mapping <span class="hlt">Plate</span> Tectonic Boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">To prepare for this activity, students do background reading on <span class="hlt">Plate</span> Tectonics from the course textbook. Students also participate in a lecture on the discovery and formulation of the unifying theory of <span class="hlt">plate</span> tectonics, and the relationship between <span class="hlt">plate</span> boundaries and geologic features such as volcanoes. Lastly, in lecture, students are introduced to a series of geologic hazards caused by certain <span class="hlt">plate</span> tectonic interactions. The activity gives students practices at identifying <span class="hlt">plate</span> boundaries and allows them to explore lesser known tectonically active regions.</p> <div class="credits"> <p class="dwt_author">Kerwin, Michael</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">286</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009Sci...324..226F"> <span id="translatedtitle">A Great Earthquake Rupture Across a Rapidly Evolving Three-<span class="hlt">Plate</span> Boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">On 1 April 2007 a great, tsunamigenic earthquake (moment magnitude 8.1) ruptured the Solomon Islands subduction zone at the triple junction where the Australia and Solomon Sea-Woodlark Basin <span class="hlt">plates</span> simultaneously underthrust the Pacific <span class="hlt">plate</span> with different slip directions. The associated abrupt change in slip direction during the great earthquake drove convergent anelastic deformation of the upper Pacific <span class="hlt">plate</span>, which generated localized uplift in the forearc above the subducting Simbo fault, potentially amplifying local tsunami amplitude. Elastic deformation during the seismic cycle appears to be primarily accommodated by the <span class="hlt">overriding</span> Pacific forearc. This earthquake demonstrates the seismogenic potential of extremely young subducting oceanic lithosphere, the ability of ruptures to traverse substantial geologic boundaries, and the consequences of complex coseismic slip for uplift and tsunamigenesis.</p> <div class="credits"> <p class="dwt_author">Furlong, Kevin P.; Lay, Thorne; Ammon, Charles J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">287</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1512845K"> <span id="translatedtitle">Arctic and Antarctic Crustal Thickness and <span class="hlt">Continental</span> Lithosphere Thinning from Gravity Inversion</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Mapping crustal thickness, <span class="hlt">continental</span> lithosphere thinning and oceanic lithosphere distribution represents a substantial challenge for the Polar Regions. The Arctic region formed as a series of small distinct ocean basins leading to a complex distribution of oceanic crust, thinned <span class="hlt">continental</span> crust and rifted <span class="hlt">continental</span> margins. Antarctica, both peripherally and internally, experienced poly-phase rifting and <span class="hlt">continental</span> breakup. We determine Moho depth, crustal basement thickness, <span class="hlt">continental</span> lithosphere thinning and ocean-continent transition location for the Polar Regions using a gravity inversion method which incorporates a lithosphere thermal gravity anomaly correction. The method is carried out in the 3D spectral domain and predicts Moho depth and incorporates a lithosphere thermal gravity anomaly correction. Ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. A correction to the predicted <span class="hlt">continental</span> lithospheric thinning derived from gravity inversion is made for volcanic material addition produced by decompression melting during <span class="hlt">continental</span> rifting and seafloor spreading. For the Arctic, gravity data used is from the NGA (U) Arctic Gravity Project, bathymetry is from IBCAO and sediment thickness is from a new regional compilation. For Antarctica and the Southern Oceans, data used are elevation and bathymetry, free-air gravity anomaly, ice and sediment thickness from Smith and Sandwell (2008), Sandwell and Smith (2008) and Laske and Masters (1997) respectively, supplemented by Bedmap2 data south of 60 degrees south. Using gravity anomaly inversion, we have produced the first comprehensive maps of crustal thickness and oceanic lithosphere distribution for the Arctic, Antarctica and the Southern Ocean. Our gravity inversion predicts thin crust and high <span class="hlt">continental</span> lithosphere thinning factors in the Makarov, Podvodnikov, Nautilus and Canada Basins consistent with these basins being oceanic or highly thinned <span class="hlt">continental</span> crust. Larger crustal thicknesses, in the range 20 - 30 km, are predicted for the Lomonosov, Alpha and Mendeleev Ridges. Moho depths predicted compare well with seismic estimates. Predicted very thin <span class="hlt">continental</span> or oceanic crust under the North Chuchki Basin and Laptev Sea has major implications for understanding the <span class="hlt">plate</span> tectonic history of the Amerasia Basin. Our gravity inversion study predicts thick crust (> 45 km) under interior East Antarctica. Thin crust is predicted under the West Antarctica Rift System and the Ross Sea. Continent scale rifts are also seen within East Antarctica. Intermediate crustal thickness with a pronounced rift fabric is predicted under Coates Land. An extensive region of either thick oceanic crust or highly thinned <span class="hlt">continental</span> crust is predicted offshore Oates Land and north Victoria Land. Superposition of illuminated satellite gravity data onto crustal thickness maps from gravity inversion provides improved determination of rift orientation, pre-breakup rifted margin conjugacy and <span class="hlt">continental</span> breakup trajectory (e.g. for the Southern Ocean). Gravity inversion predictions of crustal thickness, OCT location and oceanic lithosphere distribution may be used to test <span class="hlt">plate</span> tectonic reconstructions. Using gravity anomaly inversion mapping of <span class="hlt">continental</span> lithosphere thinning we have developed and applied a new technique to predict basement heat-flow, important for the prediction of ice-sheet stability, for the Polar Regions.</p> <div class="credits"> <p class="dwt_author">Kusznir, Nick J.; Alvey, Andy; Vaughan, Alan P. M.; Ferraccioli, Fausto; Jordan, Tom A. R. M.; Roberts, Alan M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">288</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1513916G"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: From Initiation of Subduction to Global <span class="hlt">Plate</span> Motions (Augustus Love Medal Lecture)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary"><span class="hlt">Plates</span> are driven by buoyancy forces distributed in the mantle, within cooling oceanic <span class="hlt">plates</span> (ridge push) and within subducted slabs. Although the case is often made that subducted slabs provide the principle driving force on <span class="hlt">plate</span> motion, consensus has not been achieved. This is at least partially due to the great difficulty in realistically capturing the role of slabs in observationally-constrained models as slabs act to drive and resist <span class="hlt">plate</span> motions through their high effective viscosity. Slab buoyancy acts directly on the edge of the <span class="hlt">plate</span> (slab pull), while inducing mantle flow that tends to drag both subducting and <span class="hlt">overriding</span> <span class="hlt">plates</span> toward the trench. While <span class="hlt">plates</span> bend during subduction they undergo a form of 'plastic failure' (as evident through faulting, seismicity and reduction of flexural parameters at the outer trench wall). The birth of a new subduction zone, subduction initiation, provides important insight into <span class="hlt">plate</span> motions and subduction dynamics. About half of all subduction zones initiated over the Cenozoic and the geophysical and geological observations of them provide first order constraints on the mechanics of how these margins evolved from their preexisting tectonic state to self-sustaining subduction. We have examples of subduction initiation at different phases of the initiation process (e.g. early versus late) as well as how margins have responded to different tectonic forcings. The consequences of subduction initiation are variable: intense trench roll back and extensive boninitic volcanism followed initiation of the Izu-Bonin-Mariana arc while both were absent during Aleutian arc initiation. Such differences may be related to the character of the preexisting <span class="hlt">plates</span>, the size of and forces on the <span class="hlt">plates</span>, and how the lithosphere was initially bending during initiation. I will address issues associated with the forces driving <span class="hlt">plate</span> tectonics and initiating new subduction zones from two perspectives. A common thread is the origin and evolution of intense back arc spreading and rapid roll back associated with some ocean-ocean subduction zones. I will look at the dynamics driving global <span class="hlt">plate</span> motions and the time-dependence of trench rollback regionally. Capitalizing on advances in adaptive mesh refinement algorithms on parallel computers with individual <span class="hlt">plate</span> margins resolved down to a scale of 1 kilometer, observationally constrained, high-resolution models of global mantle flow now capture the role of slabs and show how <span class="hlt">plate</span> tectonics is regulated by the rheology of slabs. Back-arc extension and slab rollback are emergent consequences of slab descent in the upper mantle. I will then describe regional, time-dependent models, address the causes and consequences of subduction initiation, and show that most back arc extension follows subduction initiation. Returning to the global models, inverse models using the full adjoint of the variable viscosity, Stokes equation are now possible and allow an even greater link between present-day geophysical observations and the dynamics from local to global scales.</p> <div class="credits"> <p class="dwt_author">Gurnis, Michael</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">289</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40925201"> <span id="translatedtitle">Isotopic composition of helium, and CO 2 and CH 4 contents in gases produced along the New Zealand part of a convergent <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">New Zealand straddles an active tectonic boundary between the Indo-Australian and Pacific <span class="hlt">plates</span>. To the NE and SW oblique convergence of oceanic and <span class="hlt">continental</span> crusts leads to the establishment of subduction zones; in the center <span class="hlt">continental</span> crusts collide along a transform boundary. With regard to mantle degassing, and on the basis of chemical and He isotopic analyses of 140 samples</p> <div class="credits"> <p class="dwt_author">W. F. Giggenbach; Y. Sano; H. Wakita</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">290</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60044573"> <span id="translatedtitle">Isotopic composition of helium, and CO[sub 2] and CH[sub 4] contents in gases produced along the New Zealand part of a convergent <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">New Zealand straddles an active tectonic boundary between the Indo-Australian and Pacific <span class="hlt">plates</span>. To the NE and SW oblique convergence of oceanic and <span class="hlt">continental</span> crusts leads to the establishment of subduction zones; in the center <span class="hlt">continental</span> crusts collide along a transform boundary. With regard to mantle degassing, and on the basis of chemical and He isotopic analyses of 140 samples</p> <div class="credits"> <p class="dwt_author">W. F. Giggenbach; Y. Sano; H. Wakita</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">291</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.V54A..01S"> <span id="translatedtitle">Characteristics and origin of <span class="hlt">Continental</span> and Oceanic Intraplate Volcanism</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Intraplate volcanism not clearly associated with <span class="hlt">plate</span> margin tectonics or mantle plumes occurs in both <span class="hlt">continental</span> and oceanic environments. A compilation of intraplate volcanic fields indicates several common traits: (1) volcanoes are predominately alkali basalt although tholeiitic, bimodal rhyolite basalt and calc-alkaline magma types occur in the Basin and Range and Utah Transition Zone in the western US; (2) volcanoes are monogenetic and occur in separate volcanic fields that rarely display time migration; (3) intraplate <span class="hlt">continental</span> volcanic fields form by repeated episodic eruptions over a long period of time (10 m.y. or longer) in a limited geographic area; (4) extended or fractured intraplate areas tend to localize volcanism and (5) in oceanic environments, intraplate volcanism may produce island chains, but chains lack the time progression expected in plume related volcanism. Although intraplate volcanoes have been studied for decades there is little agreement on a mechanism that explains their formation. A selection of recently proposed mechanisms include “hot fingers or mini plumes” (eastern Australia), melting of fertile lithospheric mantle (Jordan, Basin and Range USA), mantle diapirs and crustal extension (Calatrava Spain), “petit spot” volcanoes formed along fractures related to <span class="hlt">plate</span> flexure (northwestern Pacific <span class="hlt">Plate</span>), hot line or tectono-magmatic alignment (Cameroon west Africa), upwelling of hot asthenosphere associated with deep subduction and a stagnant slab (Changbai volcano China), rifting of foreland uplifts associated with distant subduction (Rhine Graben), mantle plumes (Eifel Germany), small scale sublithospheric convection (SSC) (Gilbert and Pukapuka ridges Pacific <span class="hlt">Plate</span>) and shear driven asthenospheric upwelling (SDU) (Basin and Range USA). Although all of these mechanisms have their merits, few explain the longevity of intraplate volcanism and repeated eruptions in the same geographic area. SSC [1] invokes the slow replacement of depleted mantle with fertile fresh magma allowing melting to occur in the same area for long periods of time. SDU related melting is generated by upwelling caused solely by the action of asthenospheric shear flow on viscosity heterogeneity [2]. SDU in low-viscosity pockets in the asthenosphere may be localized by topography at the base of the lithosphere and could provide a satisfactory explanation for the longevity and geographic distribution of intraplate volcanism. [1] Balmer, van Hunen, Ito, Tackley, Bianco (2007) Geophys. Res. Lett. 34, ISI-00025169300002. [2] Conrad, Wu, E. Smith, Bianco, Tibbetts (2009), PEPI in review.</p> <div class="credits"> <p class="dwt_author">Smith, E. I.; Conrad, C. P.; Johnsen, R. L.; Tibbetts, A. K.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">292</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.V43H..05S"> <span id="translatedtitle">Mantle Calcium Dominates <span class="hlt">Continental</span> Magmas</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Trace element and isotopic compositions of <span class="hlt">continental</span> igneous rocks are often used to model the generation and evolution of crustal magmas. Here we report new Ca isotopic measurements of crystal-poor (<10%) to monotonous crystal-rich (>35%) rhyolites from the Oligocene San Juan Volcanic Field (SJVF) and Pliocene to Pleistocene tuffs from Yellowstone Caldera. Because both volcanic fields are located within the North American craton the extruded magmas could have assimilated old crustal source components with radiogenic Ca that would be clearly distinguishable from that of the mantle. New Ca data are also reported for two crustal xenoliths found within the 28.2 Ma Fish Canyon Tuff (FCT) of the SJVF that yield ?Ca values of 3.8±0.6 (2 ?, n=3) and 7.5±0.4 (2 ?, n=3), respectively. The 40Ca excesses of these possible source rocks are due to long-term in situ 40K decay and suggest that they are Precambrian in age. In contrast to the excess radiogenic Ca signatures, most Cenozoic basalts and many silicic igneous rocks from Earth yield initial ?Ca values close to zero, which indicates that the 40Ca/44Ca ratio of the Earth’s mantle is well defined and virtually invariant at the resolution of our measurements. The crystal-rich FCT, inferred to result from batholith-scale remobilization of a shallow subvolcanic magma chamber, exhibits an ?Cai value of 0.32±0.02 (2 ?, n=5) that is indistinguishable from Ca in clinopyroxene from an ultramafic xenolith that has a mantle-like ?Cai value of -0.35±0.62 (2 ?, n=2). Simple mass balance calculations indicate that Ca in the FCT is greater than ~75% mantle derived. Similar mixing models based on published Nd data for the FCT that consider the range of possible crustal source components can deviate substantially from the Ca models. At face value the Nd data indicate that the FCT magma underwent significant crustal assimilation (i.e., at least ~10% and possibly ~75% of the Nd appears to have come from an enriched source component). So even in cases where a crustal component is clear (like the FCT), the importance of mantle magma input can be shown with Ca isotopes. The Ca isotopic compositions of the Lava Creek Tuff = 0.28±0.09 (2 ?, n=4) and Huckleberry Ridge Tuff = 0.11±0.17 (2 ?, n=1) of Yellowstone also imply substantial mantle sources. Crystal-poor ignimbrites from the SJVF exhibit similar to slightly higher ?Cai values. These include the Sapinero Mesa Tuff that has an ?Cai = 0.32±0.41 (2 ?, n=5), the Tuff of Saguache = 0.55±0.12 (2 ?, n=2), and the Blue Mesa Tuff = 1.77±0.64 (2 ?, n=3), respectively. Where ?Cai is clearly higher than zero (i.e., above +1.5), it is a good indication that the silicic magma has a source in the <span class="hlt">continental</span> crust. In extrusions where low ?Nd could also be due to melting from enriched reservoirs in the mantle lithosphere, the combination of high ?Cai with low ?Nd clearly identifies crustal melts. The mantle dominated isotopic composition of a major lithophile element in silicic magmas suggests that a significant component of their source rocks were either poor in incompatible elements and/or that the silicic magmas represent recent additions to the <span class="hlt">continental</span> crust.</p> <div class="credits"> <p class="dwt_author">Simon, J. I.; Depaolo, D. J.; Bachmann, O.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">293</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5587891"> <span id="translatedtitle">Regional magnetic anomaly constraints on <span class="hlt">continental</span> breakup</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary"><span class="hlt">Continental</span> lithosphere magnetic anomalies mapped by the Magsat satellite are related to tectonic features associated with regional compositional variations of the crust and upper mantle and crustal thickness and thermal perturbations. These <span class="hlt">continental</span>-scale anomaly patterns when corrected for varying observation elevation and the global change in the direction and intensity of the geomagnetic field show remarkable correlation of regional lithospheric magnetic sources across rifted <span class="hlt">continental</span> margins when plotted on a reconstruction of Pangea. Accordingly, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans.</p> <div class="credits"> <p class="dwt_author">von Frese, R.R.B.; Hinze, W.J.; Olivier, R.; Bentley, C.R.</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">294</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5031755"> <span id="translatedtitle"><span class="hlt">Continental</span> margin tectonics - Forearc processes</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Recent studies of convergent <span class="hlt">plate</span> margins and the structural development of forearc terranes are summarized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the geometry of accretionary prisms (Coulomb wedge taper and vertical motion in response to tectonic processes), offscraping vs underplating or subduction, the response to oblique convergence, fluids in forearc settings, the thermal framework and the effects of fluid advection, and serpentinite seamounts. Also included is a comprehensive bibliography for the period.</p> <div class="credits"> <p class="dwt_author">Lundberg, N.; Reed, D.L. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">295</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.T41C2037M"> <span id="translatedtitle">From oceanic to <span class="hlt">continental</span> subduction in Taiwan: Dynamics of a growing orogenic wedge</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">In Taiwan, obliquity of <span class="hlt">plate</span> convergence involves the progressive subduction of the <span class="hlt">continental</span> margin of China under the Philippine Sea <span class="hlt">Plate</span> (PSP). From south to north, transition from oceanic to <span class="hlt">continental</span> subduction induces the growth of the orogenic wedge involving (1) in the domain of incipient <span class="hlt">continental</span> subduction to the south, major eastward backthrusting and shortening of the forearc domain between the former oceanic wedge and the Luzon arc and, (2) where <span class="hlt">continental</span> subduction is mature to the north, accretion of deformed parts of the volcanic arc edifice. Geological observations show that the forearc domain is very narrow along eastern Taiwan and that the arc is probably absent to the north of 24°N, suggesting that the frontal part of the arc has been subducted. In the core of the growing wedge, metamorphic rocks of the Central Range were progressively exhumed in a few My, rising through the overlying rocks of the former oceanic wedge. Strain partitioning caused by the combined effects of erosion and underplating at depth favored exhumation in the hinterland. During uplift, eroding rocks of the oceanic wedge (including ophiolite blocks of former mélanges) became the source for the olistostromal blocks. Mixed with deforming rocks from the forearc, they were included in the Lichi mélange. Detrital sediments were deposited in collisional basins and simultaneously deformed during shortening of the forearc domain. Then asymmetrical mechanism of wedge growth by forward thrusting that had been operating in the Taiwan region up to this time was replaced by a more symmetrical evolution with significant backthrusting. At this stage, the tip of the arc basement enters in the collision process, indenting the Central Range, which is now cut by an east-dipping, out-of-sequence thrust. Lastly, a major west-dipping thrust develops in response to indentation by the arc lithosphere. It could cut across the <span class="hlt">continental</span> lithosphere of the China margin, may be initiating a subduction reversal. Tectonic evolutionary model for Taiwan</p> <div class="credits"> <p class="dwt_author">Malavieille, J.; Lu, C.; Chang, K.; Stephane, D.; Serge, L.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">296</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3473047"> <span id="translatedtitle">Mirrored Prominent Deck B Phenomenon: Frequent Small Losses <span class="hlt">Override</span> Infrequent Large Gains in the Inverted Iowa Gambling Task</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p class="result-summary">Since Bechara et al. pioneered its development, the Iowa Gambling Task (IGT) has been widely applied to elucidate decision behavior and medial prefrontal function. Although most decision makers can hunch the final benefits of IGT, ventromedial prefrontal lesions generate a myopic choice pattern. Additionally, the Iowa group developed a revised IGT (inverted IGT, iIGT) to confirm the IGT validity. Each iIGT trial was generated from the trial of IGT by multiplying by a “?” to create an inverted monetary value. Thus, bad decks A and B in the IGT become good decks iA and iB in the iIGT; additionally, good decks C and D in the IGT become bad decks iC and iD in the iIGT. Furthermore, IGT possessed mostly the gain trials, and iIGT possessed mainly the loss trials. Therefore, IGT is a frequent-gain–based task, and iIGT is a frequent-loss–based task. However, a growing number of IGT-related studies have identified confounding factors in IGT (i.e., gain-loss frequency), which are demonstrated by the prominent deck B phenomenon (PDB phenomenon). Nevertheless, the mirrored PDB phenomenon and guiding power of gain-loss frequency in iIGT have seldom been reexamined. This experimental finding supports the prediction based on gain-loss frequency. This study identifies the mirrored PDB phenomenon. Frequent small losses <span class="hlt">override</span> occasional large gains in deck iB of the iIGT. Learning curve analysis generally supports the phenomenon based on gain-loss frequency rather than final outcome. In terms of iIGT and simple versions of iIGT, results of this study demonstrate that high-frequency loss, rather than a satisfactory final outcome, dominates the preference of normal decision makers under uncertainty. Furthermore, normal subjects prefer “no immediate punishment” rather than “final reward” under uncertainty.</p> <div class="credits"> <p class="dwt_author">Lin, Ching-Hung; Song, Tzu-Jiun; Lin, Yu-Kai; Chiu, Yao-Chu</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">297</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/21329200"> <span id="translatedtitle">Modeling the dynamics of <span class="hlt">continental</span> shelf carbon.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary"><span class="hlt">Continental</span> margin systems are important contributors to global nutrient and carbon budgets. Effort is needed to quantify this contribution and how it will be modified under changing patterns of climate and land use. Coupled models will be used to provide projections of future states of <span class="hlt">continental</span> margin systems. Thus, it is appropriate to consider the limitations that impede the development of realistic models. Here, we provide an overview of the current state of modeling carbon cycling on <span class="hlt">continental</span> margins as well as the processes and issues that provide the next challenges to such models. Our overview is done within the context of a coupled circulation-biogeochemical model developed for the northeastern North American <span class="hlt">continental</span> shelf region. Particular choices of forcing and initial fields and process parameterizations are used to illustrate the consequences for simulated distributions, as revealed by comparisons to observations using quantitative statistical metrics. PMID:21329200</p> <div class="credits"> <p class="dwt_author">Hofmann, Eileen E; Cahill, Bronwyn; Fennel, Katja; Friedrichs, Marjorie A M; Hyde, Kimberly; Lee, Cindy; Mannino, Antonio; Najjar, Raymond G; O'Reilly, John E; Wilkin, John; Xue, Jianhong</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">298</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=ADA180143"> <span id="translatedtitle">Carbonates of the Louisiana <span class="hlt">Continental</span> Slope.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">The <span class="hlt">continental</span> slope off central Louisiana has extremely complex surface topography as well as subsurface structures that are primarily inherited from salt tectonics, with other features generated by differential sedimentation, erosion, and mass movement...</p> <div class="credits"> <p class="dwt_author">H. H. Roberts R. Sassen P. Aharon</p> <p class="dwt_publisher"></p> <p class="publishDate">1987-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">299</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..12.6753S"> <span id="translatedtitle">The effect of <span class="hlt">continental</span> lids on the long-term efficiency of mantle convective stirring</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Interpreting surface geochemical data requires the understanding of the dynamic mechanisms that can preserve or erase chemical heterogeneities over geological times. Among these, the presence of <span class="hlt">continental</span> lids is known to have a first order impact on mantle convective dynamics and heat transfer. On Earth oceanic <span class="hlt">plates</span> are recycled into the mantle and are characterized by a relatively strong heat flux, while continents are more insulating, lighter and therefore not subductable. Numerical and laboratory experiments have demonstrated that the dichotomy between continents and oceans can have a first order influence on mantle motions. One should therefore expect that this influence also reflects on the efficiency of convective stirring over billions of years. However, this effect has not been considered in previous studies that investigated mantle convective stirring efficiency. We have therefore investigated the influence of <span class="hlt">continental</span> lids on convective stirring efficiency using numerical experiments at infinite Prandtl number, in rectangular domain. Differences between oceanic and <span class="hlt">continental</span> <span class="hlt">plates</span> are accounted for by imposing heterogeneous surface boundary conditions for temperature and velocities: oceanic <span class="hlt">plates</span> are described by Dirichlet boundary conditions while continents are modeled as highly viscous, floating lids of variable extent, locally imposing a prescribed surface heat flux. We use passively advected tracers to quantify the stirring efficiency with various diagnostics such as mixing time and Lyapunov exponent distribution. This numerical set up allows us to quantify systematically the influence of several governing parameters on the convective stirring efficiency: the Rayleigh number Ra, the horizontal extent of <span class="hlt">continental</span> lids, as well as the magnitude of their insulating character.</p> <div class="credits"> <p class="dwt_author">Samuel, Henri; Deo, Bhaskar</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">300</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://pubs.er.usgs.gov/publication/70011594"> <span id="translatedtitle">Freshwater peat on the <span class="hlt">continental</span> shelf</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">Freshwater peats from the <span class="hlt">continental</span> shelf off northeastern United States contain the same general pollen sequence as peats from ponds that are above sea level and that are of comparable radiocarbon ages. These peats indicate that during glacial times of low sea level terrestrial vegetation covered the region that is now the <span class="hlt">continental</span> shelf in an unbroken extension from the adjacent land areas to the north and west.</p> <div class="credits"> <p class="dwt_author">Emery, K. O.; Wigley, R. L.; Bartlett, A. S.; Rubin, M.; Barghoorn, E. S.</p> <p class="dwt_publisher"></p> <p class="publishDate">1967-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_14");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a style="font-weight: bold;">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_16");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_15 div --> <div id="page_16" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_15");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a style="font-weight: bold;">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_17");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">301</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/49567348"> <span id="translatedtitle">Increased loss of <span class="hlt">continental</span> crust during supercontinent amalgamation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The volume of Earth's <span class="hlt">continental</span> crust depends on the rate of addition of <span class="hlt">continental</span> crust from the mantle compared to the rate of <span class="hlt">continental</span> loss back to the mantle, which at present is roughly balanced. Models for the growth rate of <span class="hlt">continental</span> crust vary, with isotope data suggesting various episodes of increased growth rate throughout Earth's history; these episodes have</p> <div class="credits"> <p class="dwt_author">Nick M. W. Roberts</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">302</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007E%26PSL.260..516I"> <span id="translatedtitle">Mountain belt growth inferred from histories of past <span class="hlt">plate</span> convergence: A new tectonic inverse problem</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Past <span class="hlt">plate</span> motions display a range of variability, including speedups and slowdowns that cannot easily be attributed to changes in mantle related driving forces. One key controlling factor for these variations is the surface topography at convergent margins, as previous modeling shows that the topographic load of large mountain belts consumes a significant amount of the driving forces available for <span class="hlt">plate</span> tectonics by increasing frictional forces between downgoing and <span class="hlt">overriding</span> <span class="hlt">plates</span>. Here we use this insight to pose a new tectonic inverse problem and to infer the growth of mountain belts from a record of past <span class="hlt">plate</span> convergence. We introduce the automatic differentiation method, which is a technique to produce derivative code free of truncation error by source transformation of the forward model. We apply the method to a publicly available global tectonic thin-shell model and generate a simple derivative code to relate Nazca/South America <span class="hlt">plate</span> convergence to gross topography of the Andes mountain belt. We test the code in a search algorithm to infer an optimal paleotopography of the Andes 3.2 m.y. ago from the well-known history of Nazca/South America <span class="hlt">plate</span> convergence. Our modeling results are in excellent agreement with published estimates of Andean paleotopography and support the notion of strong feedback between mountain belt growth and <span class="hlt">plate</span> convergence.</p> <div class="credits"> <p class="dwt_author">Iaffaldano, Giampiero; Bunge, Hans-Peter; Bücker, Martin</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-08-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">303</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.6616M"> <span id="translatedtitle">Stratigraphic Modelling of <span class="hlt">Continental</span> Rifting</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Interlinks between deformation and sedimentation have long been recognised as an important factor in the evolution of <span class="hlt">continental</span> rifts and basins development. However, determining the relative impact of tectonic and climatic forcing on the dynamics of these systems remains a major challenge. This problem in part derives from a lack of modelling tools capable of simulated high detailed surface processes within a large scale (spatially and temporally) tectonic setting. To overcome this issue an innovative framework has been designed using two existing numerical forward modelling codes: Underworld, capable of simulating 3D self-consistent tectonic and thermal lithospheric processes, and Tellus, a forward stratigraphic and geomorphic modelling framework dedicated to simulating highly detailed surface dynamics. The coupling framework enables Tellus to use Underworld outputs as internal and boundary conditions, thereby simulating the stratigraphic and geomorphic evolution of a realistic, active tectonic setting. The resulting models can provide high-resolution data on the stratigraphic record, grain-size variations, sediment provenance, fluvial hydrometric, and landscape evolution. Here we illustrate a one-way coupling method between active tectonics and surface processes in an example of 3D oblique rifting. Our coupled model enables us to visualise the distribution of sediment sources and sinks, and their evolution through time. From this we can extract and analyse at each simulation timestep the stratigraphic record anywhere within the model domain. We find that even from a generic oblique rift model, complex fluvial-deltaic and basin filling dynamics emerge. By isolating the tectonic activity from landscape dynamics with this one-way coupling, we are able to investigate the influence of changes in climate or geomorphic parameters on the sedimentary and landscape record. These impacts can be quantified in part via model post-processing to derive both instantaneous and cumulative erosion/sedimentation.</p> <div class="credits"> <p class="dwt_author">Mondy, Luke; Duclaux, Guillaume; Salles, Tristan; Thomas, Charmaine; Rey, Patrice</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">304</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://orthoinfo.aaos.org/topic.cfm?topic=A00040"> <span id="translatedtitle">Growth <span class="hlt">Plate</span> Fractures</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://medlineplus.gov/">MedlinePLUS</a></p> <p class="result-summary">... Harris classification of growth <span class="hlt">plate</span> fractures. Type I Fractures These fractures break through the bone at the ... and completely disrupting the growth <span class="hlt">plate</span>. Type II Fractures These fractures break through part of the bone ...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">305</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=ADD008827"> <span id="translatedtitle">Segmented Clutch <span class="hlt">Plates</span>.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">The patent application relates to a segmented annular clutch <span class="hlt">plate</span> for use in any conventional clutch <span class="hlt">plate</span> mechanism. The segments are of equal arcuate dimension so that they are interchangeable. Each segment possesses the same annular uniformily serrate...</p> <div class="credits"> <p class="dwt_author">E. F'Geppert</p> <p class="dwt_publisher"></p> <p class="publishDate">1981-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">306</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/1030723"> <span id="translatedtitle">Button/<span class="hlt">Plate</span> Yielding</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">An aluminum button and <span class="hlt">plate</span> were yielded to compare the experimental and calculated button to <span class="hlt">plate</span> stress ratios. Using the fact that compressive stress is directly proportional to area and load, the calculated button to <span class="hlt">plate</span> stress ratio is equal to the <span class="hlt">plate</span> to button area ratio for a constant load. The loads that caused the button and <span class="hlt">plate</span> to yield were estimated from a load test cell graph obtained from the materials testing facility. The button was simply compressed, but the <span class="hlt">plate</span> was compressed with a steel cylinder of the same diameter as the aluminum button. The experimental and calculated stress ratios for the button and <span class="hlt">plate</span> are the same within experimental error. The equation for the <span class="hlt">plate</span> bearing area is therefore correct.</p> <div class="credits"> <p class="dwt_author">Wintercorn, S.; /Fermilab</p> <p class="dwt_publisher"></p> <p class="publishDate">1987-06-17</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">307</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.teachersdomain.org/resources/ess05/sci/ess/earthsys/wegener2/assets/ess05_vid_wegener2/ess05_vid_wegener2_56_mov.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics: Further Evidence</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">The representation depicts the spreading of the sea floor along the mid-ocean ridges. The resource generally describes the theory of <span class="hlt">plate</span> tectonics, including the movement of <span class="hlt">plates</span> with regard to one another.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">308</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://learningcenter.nsta.org/product_detail.aspx?id=10.2505/15/ERNASA10_0180"> <span id="translatedtitle">External Resource: <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This Windows to the Universe interactive webpage connects students to the study and understanding of <span class="hlt">plate</span> tectonics, the main force that shapes our planets surface. Topics: <span class="hlt">plate</span> tectonics, lithosphere, subduction zones, faults, ridges.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1900-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">309</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/969705"> <span id="translatedtitle">Earth's Decelerating Tectonic <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Space geodetic and oceanic magnetic anomaly constraints on tectonic <span class="hlt">plate</span> motions are employed to determine a new global map of present-day rates of change of <span class="hlt">plate</span> velocities. This map shows that Earth's largest <span class="hlt">plate</span>, the Pacific, is presently decelerating along with several other <span class="hlt">plates</span> in the Pacific and Indo-Atlantic hemispheres. These <span class="hlt">plate</span> decelerations contribute to an overall, globally averaged slowdown in tectonic <span class="hlt">plate</span> speeds. The map of <span class="hlt">plate</span> decelerations provides new and unique constraints on the dynamics of time-dependent convection in Earth's mantle. We employ a recently developed convection model constrained by seismic, geodynamic and mineral physics data to show that time-dependent changes in mantle buoyancy forces can explain the deceleration of the major <span class="hlt">plates</span> in the Pacific and Indo-Atlantic hemispheres.</p> <div class="credits"> <p class="dwt_author">Forte, A M; Moucha, R; Rowley, D B; Quere, S; Mitrovica, J X; Simmons, N A; Grand, S P</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-08-22</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">310</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17799689"> <span id="translatedtitle">Accelerated <span class="hlt">plate</span> tectonics.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">The concept of a stressed elastic lithospheric <span class="hlt">plate</span> riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent <span class="hlt">plate</span> boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that <span class="hlt">plate</span> motions accelerate after great decoupling earthquakes and that most of the observed <span class="hlt">plate</span> motions occur during short periods of time, separated by periods of relative quiescence. PMID:17799689</p> <div class="credits"> <p class="dwt_author">Anderson, D L</p> <p class="dwt_publisher"></p> <p class="publishDate">1975-03-21</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">311</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/21505441"> <span id="translatedtitle">Mapping the evolving strain field during <span class="hlt">continental</span> breakup from crustal anisotropy in the Afar Depression.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Rifting of the continents leading to <span class="hlt">plate</span> rupture occurs by a combination of mechanical deformation and magma intrusion, yet the spatial and temporal scales over which these alternate mechanisms localize extensional strain remain controversial. Here we quantify anisotropy of the upper crust across the volcanically active Afar Triple Junction using shear-wave splitting from local earthquakes to evaluate the distribution and orientation of strain in a region of <span class="hlt">continental</span> breakup. The pattern of S-wave splitting in Afar is best explained by anisotropy from deformation-related structures, with the dramatic change in splitting parameters into the rift axis from the increased density of dyke-induced faulting combined with a contribution from oriented melt pockets near volcanic centres. The lack of rift-perpendicular anisotropy in the lithosphere, and corroborating geoscientific evidence of extension dominated by dyking, provide strong evidence that magma intrusion achieves the majority of <span class="hlt">plate</span> opening in this zone of incipient <span class="hlt">plate</span> rupture. PMID:21505441</p> <div class="credits"> <p class="dwt_author">Keir, Derek; Belachew, M; Ebinger, C J; Kendall, J-M; Hammond, J O S; Stuart, G W; Ayele, A; Rowland, J V</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">312</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..1414203K"> <span id="translatedtitle">Mapping the evolving strain field during <span class="hlt">continental</span> breakup from crustal anisotropy in the Afar Depression</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Rifting of the continents leading to <span class="hlt">plate</span> rupture occurs by a combination of mechanical deformation and magma intrusion, yet the spatial and temporal scales over which these alternate mechanisms localize extensional strain remains controversial. Here we quantify anisotropy of the upper crust across the volcanically active Afar Triple Junction using shear-wave splitting from local earthquakes to evaluate the distribution and orientation of strain in a region of <span class="hlt">continental</span> breakup. The pattern of S-wave splitting in Afar is best explained by anisotropy from deformation-related structures, with the dramatic change in splitting parameters into the rift axis from the increased density of dyke-induced faulting combined with a contribution from oriented melt pockets near volcanic centres. The lack of rift-perpendicular anisotropy in the lithosphere, and corroborating geoscientific evidence of extension dominated by dyking, provide strong evidence that magma intrusion achieves the majority of <span class="hlt">plate</span> opening in this zone of incipient <span class="hlt">plate</span> rupture.</p> <div class="credits"> <p class="dwt_author">Keir, D.; Belachew, M.; Ebinger, C.; Kendall, M.; Hammond, J.; Stuart, G.; Ayele, A.; Rowland, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">313</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/26241419"> <span id="translatedtitle">Optimal truss <span class="hlt">plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Sandwich <span class="hlt">plates</span> comprised of truss cores faced with either planar trusses or solid sheets are optimally designed for minimum weight subject to prescribed combinations of bending and transverse shear loads. Motivated by recent advances in manufacturing possibilities, attention is focussed on <span class="hlt">plates</span> with truss elements and faces made from a single material. The optimized <span class="hlt">plates</span> are compared with similarly optimized</p> <div class="credits"> <p class="dwt_author">Nathan Wicks; John W Hutchinson</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">314</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://earthquake.usgs.gov/learn/topics/plate_tectonics/rift_man.php"> <span id="translatedtitle">Earthquakes and <span class="hlt">Plate</span> Tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This article describes the theory of <span class="hlt">plate</span> tectonics and its relation to earthquakes and seismic zones. Materials include an overview of <span class="hlt">plate</span> tectonics, a description of Earth's crustal <span class="hlt">plates</span> and their motions, and descriptions of the four types of seismic zones.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">315</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://crack.seismo.unr.edu/ftp/pub/louie/class/plate-syll.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonic Theory</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This is the web site for a <span class="hlt">Plate</span> Tectonics Theory class at The University of Nevada, Reno. The home page/syllabus contains links to several of the topics covered in the course. The topics with web based lecture materials are earthquake seismology, structure of the Earth, composition of the Earth, lithospheric deformation, the <span class="hlt">plate</span> tectonics paradigm, and the driving mechanisms of <span class="hlt">plate</span> tectonics.</p> <div class="credits"> <p class="dwt_author">Louie, John</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">316</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://csmres.jmu.edu/geollab/Fichter/PlateTect/index.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonic Primer</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This site gives an in-depth look at the theory of <span class="hlt">plate</span> tectonics and how it works. The structure of the Earth is discussed, with brief rock type descriptions. The structure of the lithosphere, <span class="hlt">plate</span> boundaries, interplate relationships, and types of <span class="hlt">plates</span> are all covered in detail.</p> <div class="credits"> <p class="dwt_author">Fichter, Lynn</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">317</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.T12B..02I"> <span id="translatedtitle">Feedback between mountain belt growth and <span class="hlt">plate</span> convergence revealed by forward and inverse tectonic models</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">While it is generally assumed that global <span class="hlt">plate</span> motions are driven by the pattern of convection in the Earth's mantle, the details of that linkage remain obscure. Bouyancy forces associated with subduction of cool, dense lithosphere at zones of <span class="hlt">plate</span> convergence are thought to provide significant driving force, but the relative magnitudes of other driving and resisting forces are less clear. The ability to consider past as well as present <span class="hlt">plate</span> motions provides significant additional constraints, because changes in <span class="hlt">plate</span> motion are necessarily driven by changes in one or more driving or resisting forces, which may be inferred from independent data. Here we first exploit the capabilities of forward tectonic models of the Andean region to infer <span class="hlt">plate</span> motion changes as far back as Miocene time. By accurately predicting observed convergence rates between Nazca and South America <span class="hlt">plates</span> over the last 10 Myrs, we demonstrate for the first time that the topographic load of the Andes increases frictional forces between downgoing and <span class="hlt">overriding</span> <span class="hlt">plates</span> and thus consumes a significant amount of the driving force available for <span class="hlt">plate</span> tectonics. This result suggests a strong feedback between mountain belt growth and <span class="hlt">plate</span> convergence. We then test this notion by performing a numerical inversion of the same model. We use the Automatic Differentiation approach to generate a derivative code that relates convergence of the Nazca/South America <span class="hlt">plates</span> to gross topography of the Andes mountain belt. We test the derivative code in a simple search algorithm to infer an optimal paleotopography of the Andes at 3.2 m.y. from the well-known history of Nazca/South America <span class="hlt">plate</span> convergence. Our modeling result is in good agreement with independent published estimates of Andean paleotopography.</p> <div class="credits"> <p class="dwt_author">Iaffaldano, G.; Bunge, H.; Dixon, T. H.; Buecker, M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">318</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1998ESRv...44...95K"> <span id="translatedtitle">Extending a thickened crustal bulge: toward a new geodynamic evolution model of the paleozoic NW Bohemian Massif, German <span class="hlt">Continental</span> Deep Drilling site (SE Germany)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Fault-bounded (tectonic) metamorphic complexes assembling the NW Bohemian Massif around the German <span class="hlt">Continental</span> Deep Drilling (KTB) site are seen to be extremely heterogeneous in tectonic and metamorphic histories. In current models, the different complexes were supposed to reflect a puzzle of small pre-Devonian microplates, and the related collision events supposedly lasted until the Carboniferous. Opposed to these models, it will be shown that all the boundaries among the complexes were formed by detachment, late in a prolonged overall geodynamic history of a thickened crustal bulge, during extensional tectonics and associated thermal events that outlasted the onset of collision in the Silurian/Lower Devonian by about 70-80 Ma. (Micro-)structures, petrological and geochronological data of individual complexes predominantly preserve the late stages rather than the unbroken record of their tectonometamorphic histories. Such partial histories strongly different among individual complexes, depict diverse snapshots taken at different places in the evolving thickened crustal bulge and at different instants in its overall evolution, and do not define different precollisional microplates. Predominantly P- T and deformation episodes after terrane juxtaposition are preserved. This article presents an integrated view of the structural geology, microscopic fabrics, P- T data and geochronology of such diverse metamorphic complexes. This integrated view provides a new understanding of (1) the tectonic evolution during Upper Silurian/Devonian collision of the Gondwana-derived Central European lithosphere with Laurussia, (2) the postaccretionary events that lasted through the Upper Carboniferous and (3), the earlier (Lower Ordovician) metamorphic and magmatic history, which is only locally recorded. Metamorphic complexes occupying the structurally highest position (upper tectonic complexes) record Devonian and earlier tectonometamorphic and magmatic events. After the Mid-Devonian, such complexes did not experience any metamorphism. The recorded Devonian events consist of subduction and exhumation of HP-rocks and their exhumation involved thrusting and extensional tectonics. Upper tectonic complexes comprise fragments of both the <span class="hlt">plate</span> that was subducted in this period and the <span class="hlt">overriding</span> <span class="hlt">plate</span>. In the footwall, Carboniferous extension has brought upper tectonic complexes against metamorphic complexes that essentially record Lower and Upper Carboniferous tectonometamorphic and magmatic events (lower tectonic complexes). In the lower tectonic complexes, such events are (1) consecutive extensional stages that created at least three sets of ductile normal detachment systems intersecting each other, and various associated thermal pulses, as well as (2) predetachment events that are only recorded as petrologic and structural relics transposed during extension. Inferred as predetachment events are crustal subduction as well as stacking that outlasted thrusting and exhumation of the upper tectonic complexes. In the deeper portion of the thickened crustal bulge represented by the lower tectonic complexes, spatial variations of P- T- t- d histories during decompression occurred as a result of continued differential exhumation on the three sets of detachment systems, and also from various thermal pulses that have affected different parts of this section during progressive shearing and exhumation to various degrees. Whereas the lower tectonic complexes of the Erzgebirge Gneiss Dome preserve the record of a Lower Carboniferous history of HP-metamorphism and crustal thickening followed by extension, in those of the Oberpfalz region (KTB site), a major Upper Carboniferous thermal pulse mostly erased the pre-Upper Carboniferous strain fabrics and metamorphic record. In the Oberpfalz region, ongoing extension emplaced mid-crustal rocks that pervasively equilibrated in the Upper Carboniferous at high temperatures and low pressures (low P/T ratio) against rocks not exposed to high temperatures at that time. In summary, a prolonged postaccretionary history</p> <div class="credits"> <p class="dwt_author">Krohe, Alexander</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">319</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/61323999"> <span id="translatedtitle">Estimated oil and gas reserves Gulf of Mexico outer <span class="hlt">continental</span> shelf and <span class="hlt">continental</span> slope</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Remaining recoverable reserves of oil and gas in the Gulf of Mexico Outer <span class="hlt">Continental</span> Shelf and <span class="hlt">Continental</span> Slope have been estimated to be 4.05 billion barrels of oil and 45.6 trillion cubic feet of gas, as of December 31, 1985. These reserves are recoverable from 549 studied fields located in Federal waters. For any field contained partly in State waters</p> <div class="credits"> <p class="dwt_author">J. E. Hewitt; J. P. Brooke; J. W. Compton; J. H. Knipmeyer</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">320</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60664999"> <span id="translatedtitle">Estimated oil and gas reserves, Gulf of Mexico Outer <span class="hlt">Continental</span> Shelf and <span class="hlt">Continental</span> Slope</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Remaining recoverable reserves of oil and gas in the Gulf of Mexico Outer <span class="hlt">Continental</span> Shelf and <span class="hlt">Continental</span> Slope have been estimated to be about 3.41 billion barrels of oil and 43.7 trillion cubic feet of gas, as of December 31, 1983. These reserves are recoverable from 505 studied fields under the Federal submerged lands off the coasts of Louisiana and</p> <div class="credits"> <p class="dwt_author">J. E. Hewitt; J. P. Brooke; J. H. Knipmeyer</p> <p class="dwt_publisher"></p> <p class="publishDate">1983-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_15");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a style="font-weight: bold;">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_17");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_16 div --> <div id="page_17" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_16");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a style="font-weight: bold;">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_18");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">321</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60421893"> <span id="translatedtitle">Estimated oil and gas reserves, Gulf of Mexico Outer <span class="hlt">Continental</span> Shelf and <span class="hlt">Continental</span> Slope</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Remaining recoverable reserves of oil and gas in the Gulf of Mexico Outer <span class="hlt">Continental</span> Shelf and <span class="hlt">Continental</span> Slope have been estimated to be about 2.98 billion barrels of oil and 39.8 trillion cubic feet of gas, as of December 31, 1982. These reserves are recoverable from 468 studied fields under the Federal submerged lands off the coasts of Louisiana and</p> <div class="credits"> <p class="dwt_author">J. E. Hewitt; J. P. Brooke; J. H. Knipmeyer</p> <p class="dwt_publisher"></p> <p class="publishDate">1983-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">322</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013JGRB..118.1817A"> <span id="translatedtitle">The instability of <span class="hlt">continental</span> passive margins and its effect on <span class="hlt">continental</span> topography and heat flow</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The long geological history of passive margin evolution is complex yet typified by an initial ramp-like tilting of the subaerial surface toward the continent-ocean boundary, followed by episodic uplift and subsidence at a smaller wavelength. We argue that this behavior is due to changes in margin structure brought about by buoyancy-driven lithospheric flow. <span class="hlt">Continental</span> lithosphere is melt-depleted, buoyant, and thick. It will resist convective breakdown into the asthenosphere below, but will be prone to lateral flow due to horizontal density contrasts. Changes in lithosphere thickness at the transition between continent and ocean will nucleate convection cells. Using a numerical model of viscous upper mantle flow, we show that stability or instability of the <span class="hlt">continental</span> lithosphere at a passive margin is a function of the lithospheric rheology and composition. Increased compositional buoyancy leads to oceanward lateral flow of the <span class="hlt">continental</span> lithosphere whereas decreased buoyancy has the opposite effect, causing landward lateral flow of the <span class="hlt">continental</span> lithosphere. In model simulations, a <span class="hlt">continental</span> lithosphere thought typical of Phanerozoic <span class="hlt">continental</span> platforms experiences first a margin-wide ramp-like tilting, followed by topographic fluctuations due to an evolving array of convection cells in the mantle. The timing and magnitude of predicted changes in topography are similar to those observed at the eastern North American margin, suggesting that the tilting and episodic uplift and subsidence at <span class="hlt">continental</span> passive margins are a natural consequence of the evolution of <span class="hlt">continental</span> lithosphere after breakup and during mature seafloor spreading.</p> <div class="credits"> <p class="dwt_author">Armitage, J. J.; Jaupart, C.; Fourel, L.; Allen, P. A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">323</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40847712"> <span id="translatedtitle">The rare gas inventory of the <span class="hlt">continental</span> crust, recovered by the KTB <span class="hlt">Continental</span> Deep Drilling Project</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The rare gas inventory of the <span class="hlt">continental</span> crust as mirrored in the <span class="hlt">continental</span> metamorphic rocks from the “KTB” deep drilling site in NE Bavaria, Germany, has been investigated through systematic isotope analysis of 47 whole-rock samples and 10 mineral separates from the drill core. The measured concentrations confirm a very low crustal inventory of noble gases relative to the atmosphere</p> <div class="credits"> <p class="dwt_author">J. Drescher; T. Kirsten; K. Schäfer</p> <p class="dwt_publisher"></p> <p class="publishDate">1998-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">324</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/60525545"> <span id="translatedtitle">Safety achievements of the <span class="hlt">Continental</span> Mine, <span class="hlt">Continental</span>-Archbald Coal Co. , Scranton, Lackawanna County, Pa</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">This report describing safety achievements and operating methods at the 88-year-old <span class="hlt">Continental</span> mine of the <span class="hlt">Continental</span>--Archbald Coal Co., Scranton, Pa., illustrates (to the coal-mining industry and workers in other hazardous occupations) the results of concerted efforts in preventing fatal accidents.</p> <div class="credits"> <p class="dwt_author">E. H. McCleary; H. A. Schrecengost; A. Clarkson; H. R. Gill</p> <p class="dwt_publisher"></p> <p class="publishDate">1948-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">325</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/11048717"> <span id="translatedtitle">The possible subduction of <span class="hlt">continental</span> material to depths greater than 200 km.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Determining the depth to which <span class="hlt">continental</span> lithosphere can be subducted into the mantle at convergent <span class="hlt">plate</span> boundaries is of importance for understanding the long-term growth of supercontinents as well as the dynamic processes that shape such margins. Recent discoveries of coesite and diamond in regional ultrahigh-pressure (UHP) metamorphic rocks has demonstrated that <span class="hlt">continental</span> material can be subducted to depths of at least 120 km (ref. 1), and subduction to depths of 150-300 km has been inferred from garnet peridotites in orogenic UHP belts based on several indirect observations. But <span class="hlt">continental</span> subduction to such depths is difficult to trace directly in natural UHP metamorphic crustal rocks by conventional mineralogical and petrological methods because of extensive late-stage recrystallization and the lack of a suitable pressure indicator. It has been predicted from experimental work, however, that solid-state dissolution of pyroxene should occur in garnet at depths greater than 150 km (refs 6-8). Here we report the observation of high concentrations of clinopyroxene, rutile and apatite exsolutions in garnet within eclogites from Yangkou in the Sulu UHP metamorphic belt, China. We interpret these data as resulting from the high-pressure formation of pyroxene solid solutions in subducted <span class="hlt">continental</span> material. Appropriate conditions for the Na2O concentrations and octahedral silicon observed in these samples are met at depths greater than 200 km. PMID:11048717</p> <div class="credits"> <p class="dwt_author">Ye, K; Cong, B; Ye, D</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-10-12</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">326</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/urban/activities/22207.html"> <span id="translatedtitle">Discovering <span class="hlt">Plate</span> Boundaries</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">Students are initially assigned to one of four maps of the world: Seismology, Volcanology, Geochronology or Topography. They are also given a map of the world's <span class="hlt">plate</span> boundaries and are asked to classify the boundaries based upon the data from their assigned map. Students are then assigned to a tectonic <span class="hlt">plate</span>, such that each <span class="hlt">plate</span> group contains at least one "expert" on each map. As a group, they must classify their <span class="hlt">plate</span>'s boundaries using data from all four maps. Recent volcanic and seismic events are discussed in the <span class="hlt">plate</span> tectonic context. Has minimal/no quantitative component Uses geophysics to solve problems in other fields</p> <div class="credits"> <p class="dwt_author">Henning, Alison</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">327</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6198169"> <span id="translatedtitle">North Sinai-Levant rift-transform <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The passive <span class="hlt">continental</span> margin of northern Egypt and the Levant coast formed during the Early mesozoic as the relatively small Anatolia <span class="hlt">plate</span> broke away from northern Africa. The oceanic basin of the eastern Mediterranean and the unusual right-angle bend in the North Sinai-Levant shelf margin are both products of <span class="hlt">plate</span> separation along a rift-transform fracture system, the south arm of Tethys. The north-south trending Levant transform margin is considerably narrower than the east-west trending rift margin of northern Egypt. Both exhibit similar facies and depositional histories through the mid-Tertiary. Analysis of subsurface data and published reports of the regional stratigraphy point to a three-stage tectonic evolution of this passive margin. The Triassic through mid-Cretaceous was marked by crustal breakup followed by rapid rotational subsidence of the shelf margins about hinge lines located just south and east of the present shorelines. Reef carbonates localized on the shelf edge separated a deep marine basin to the north from a deltaic-shallow marine platform to the south and east. In the Late Cretaceous-Early Tertiary, inversion of earlier formed half-grabens produced broad anticlinal upwarps of the Syrian Arc on the shelf margin that locally influenced facies patterns. The episode of inversion corresponds with the onset of northward subduction of the Africa <span class="hlt">plate</span> beneath southern Asia. Beginning in the Oligocene and continuing to the present, there has been renewed subsidence of the North Sinai shelf margin beneath thick, outward building clastic wedges. The source of this large volume of sediment is the updomed and erosionally stripped margins of the Suez-Red Sea Rift and the redirected Nile River.</p> <div class="credits"> <p class="dwt_author">Ressetar, R.; Schamel, S.; Travis, C.J.</p> <p class="dwt_publisher"></p> <p class="publishDate">1985-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">328</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/53397831"> <span id="translatedtitle">Nubia-Arabia-Eurasia <span class="hlt">plate</span> motions and the dynamics of Mediterranean and Middle East tectonics</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We use geodetic and <span class="hlt">plate</span> tectonic observations to constrain the tectonic evolution of the Nubia-Arabia-Eurasia <span class="hlt">plate</span> system. Two phases of slowing of Nubia-Eurasia convergence, each of which resulted in an ˜50 per cent decrease in the rate of convergence, coincided with the initiation of Nubia-Arabia <span class="hlt">continental</span> rifting along the Red Sea and Somalia-Arabia rifting along the Gulf of Aden at</p> <div class="credits"> <p class="dwt_author">Robert Reilinger; Simon McClusky</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">329</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010GeoJI.181....1D"> <span id="translatedtitle">Geologically current <span class="hlt">plate</span> motions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We describe best-fitting angular velocities and MORVEL, a new closure-enforced set of angular velocities for the geologically current motions of 25 tectonic <span class="hlt">plates</span> that collectively occupy 97 per cent of Earth's surface. Seafloor spreading rates and fault azimuths are used to determine the motions of 19 <span class="hlt">plates</span> bordered by mid-ocean ridges, including all the major <span class="hlt">plates</span>. Six smaller <span class="hlt">plates</span> with little or no connection to the mid-ocean ridges are linked to MORVEL with GPS station velocities and azimuthal data. By design, almost no kinematic information is exchanged between the geologically determined and geodetically constrained subsets of the global circuit-MORVEL thus averages motion over geological intervals for all the major <span class="hlt">plates</span>. <span class="hlt">Plate</span> geometry changes relative to NUVEL-1A include the incorporation of Nubia, Lwandle and Somalia <span class="hlt">plates</span> for the former Africa <span class="hlt">plate</span>, Capricorn, Australia and Macquarie <span class="hlt">plates</span> for the former Australia <span class="hlt">plate</span>, and Sur and South America <span class="hlt">plates</span> for the former South America <span class="hlt">plate</span>. MORVEL also includes Amur, Philippine Sea, Sundaland and Yangtze <span class="hlt">plates</span>, making it more useful than NUVEL-1A for studies of deformation in Asia and the western Pacific. Seafloor spreading rates are estimated over the past 0.78 Myr for intermediate and fast spreading centres and since 3.16 Ma for slow and ultraslow spreading centres. Rates are adjusted downward by 0.6-2.6mmyr-1 to compensate for the several kilometre width of magnetic reversal zones. Nearly all the NUVEL-1A angular velocities differ significantly from the MORVEL angular velocities. The many new data, revised <span class="hlt">plate</span> geometries, and correction for outward displacement thus significantly modify our knowledge of geologically current <span class="hlt">plate</span> motions. MORVEL indicates significantly slower 0.78-Myr-average motion across the Nazca-Antarctic and Nazca-Pacific boundaries than does NUVEL-1A, consistent with a progressive slowdown in the eastward component of Nazca <span class="hlt">plate</span> motion since 3.16 Ma. It also indicates that motions across the Caribbean-North America and Caribbean-South America <span class="hlt">plate</span> boundaries are twice as fast as given by NUVEL-1A. Summed, least-squares differences between angular velocities estimated from GPS and those for MORVEL, NUVEL-1 and NUVEL-1A are, respectively, 260 per cent larger for NUVEL-1 and 50 per cent larger for NUVEL-1A than for MORVEL, suggesting that MORVEL more accurately describes historically current <span class="hlt">plate</span> motions. Significant differences between geological and GPS estimates of Nazca <span class="hlt">plate</span> motion and Arabia-Eurasia and India-Eurasia motion are reduced but not eliminated when using MORVEL instead of NUVEL-1A, possibly indicating that changes have occurred in those <span class="hlt">plate</span> motions since 3.16 Ma. The MORVEL and GPS estimates of Pacific-North America <span class="hlt">plate</span> motion in western North America differ by only 2.6 +/- 1.7mmyr-1, ~25 per cent smaller than for NUVEL-1A. The remaining difference for this <span class="hlt">plate</span> pair, assuming there are no unrecognized systematic errors and no measurable change in Pacific-North America motion over the past 1-3 Myr, indicates deformation of one or more <span class="hlt">plates</span> in the global circuit. Tests for closure of six three-<span class="hlt">plate</span> circuits indicate that two, Pacific-Cocos-Nazca and Sur-Nubia-Antarctic, fail closure, with respective linear velocities of non-closure of 14 +/- 5 and 3 +/- 1mmyr-1 (95 per cent confidence limits) at their triple junctions. We conclude that the rigid <span class="hlt">plate</span> approximation continues to be tremendously useful, but-absent any unrecognized systematic errors-the <span class="hlt">plates</span> deform measurably, possibly by thermal contraction and wide <span class="hlt">plate</span> boundaries with deformation rates near or beneath the level of noise in <span class="hlt">plate</span> kinematic data.</p> <div class="credits"> <p class="dwt_author">DeMets, Charles; Gordon, Richard G.; Argus, Donald F.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">330</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/1984nasa.reptR....W"> <span id="translatedtitle">Multicolor printing <span class="hlt">plate</span> joining</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">An upper <span class="hlt">plate</span> having ink flow channels and a lower <span class="hlt">plate</span> having a multicolored pattern are joined. The joining is accomplished without clogging any ink flow paths. A pattern having different colored parts and apertures is formed in a lower <span class="hlt">plate</span>. Ink flow channels each having respective ink input ports are formed in an upper <span class="hlt">plate</span>. The ink flow channels are coated with solder mask and the bottom of the upper <span class="hlt">plate</span> is then coated with solder. The upper and lower <span class="hlt">plates</span> are pressed together at from 2 to 5 psi and heated to a temperature of from 295 F to 750 F or enough to melt the solder. After the <span class="hlt">plates</span> have cooled and the pressure is released, the solder mask is removed from the interior passageways by means of a liquid solvent.</p> <div class="credits"> <p class="dwt_author">Waters, W. J.</p> <p class="dwt_publisher"></p> <p class="publishDate">1984-03-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">331</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.rsc.org/Education/Teachers/Resources/jesei/mantle/teachers.pdf"> <span id="translatedtitle">Mantle Convection Moving <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This demonstration models the manner in which the convection currents in the mantle of the Earth cause movement of the <span class="hlt">plates</span>. Convection currents in the mantle were thought, for many years, to be solely responsible for <span class="hlt">plate</span> tectonic movements, with the movement taking rocks down at destructive margins and new rocks forming when <span class="hlt">plates</span> spread. It is now thought likely that there are three possible driving mechanisms for <span class="hlt">plate</span> tectonics. In addition to movement of mantle convection currents as shown in this demonstration, scientists also consider the mass of the subducted <span class="hlt">plate</span> (the sinking slab) at the subduction zone dragging the surface part of the <span class="hlt">plate</span> across the surface and the new <span class="hlt">plate</span> material sliding off the higher oceanic ridges at constructive margins.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">332</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..1412221H"> <span id="translatedtitle">Gravity and Flexure Modelling of Subducting <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The long-term strength of the lithosphere is determined by its flexural rigidity, which is commonly expressed through the effective elastic thickness, Te. Flexure studies have revealed a dependence of Te on thermal age. In the oceans, loads formed on young (70 Ma) seafloor. In the continents, loads on young (1000 Ma) lithosphere. Recent studies have questioned the relationship of Te with age, especially at subduction zones, where oceanic and <span class="hlt">continental</span> lithosphere are flexed downwards by up to ~6 km over horizontal distances of up to ~350 km. We have therefore used free-air gravity anomaly and topography profile data, combined with forward and inverse modelling techniques, to re-assess Te in these settings. Preliminary inverse modelling results from the Tonga-Kermadec Trench - Outer Rise system, where the Pacific <span class="hlt">plate</span> is subducting beneath the Indo-Australian <span class="hlt">plate</span>, show large spatial variations in Te that are unrelated to age. In contrast to the southern end of the system, where Te is determined by the depth to the 600° C and 900° C isotherms, the northern end of the system shows a reduction in strength. Results also suggest a reduction in Te trenchward of the outer rise that is coincident with a region of pervasive extensional faulting visible in swath bathymetry data. In a <span class="hlt">continental</span> setting, the Ganges foreland basin has formed by flexure of the Indo-Australian <span class="hlt">plate</span> in front of the migrating loads of the Himalaya. Preliminary forward modelling results, using the Himalaya as a known surface topographic load, suggest that Te is high - consistent with the great age of Indian cratonic lithosphere. However, results from inverse modelling that solves for unknown loads (vertical shear force and bending moment) show significant scatter and display trade-offs between Te and these driving loads.</p> <div class="credits"> <p class="dwt_author">Hunter, J. A.; Watts, A. B.; SO 215 Shipboard Scientific Party</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">333</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..1512972E"> <span id="translatedtitle"><span class="hlt">Plate</span> tectonics of the Scotia Sea</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The opening of the Scotia Sea ended a period of direct terrestrial connection between Antarctica and South America that had started with the amalgamation of Gondwana, and inaugurated the more recent period during which high latitude oceanic circulation between the Pacific and Atlantic oceans increased. The consequences of these changes have been suggested to include the end of terrestrial biogeographic communication across the region in Paleogene times, and the subsequent onset of southern polar isolation, bottom water formation, and Antarctic glaciation by early Neogene times. These events, responding to the configuration of land and sea, would ultimately have been governed by the configuration of <span class="hlt">continental</span> crustal units around the margins of the Scotia Sea, which in turn responded primarily to <span class="hlt">plate</span> motions and the associated <span class="hlt">plate</span> boundary processes. This presentation will put forward a model for the region's tectonic development that is derived largely from marine and satellite-derived geophysical data within it, and surrounding it. In this model, the Scotia Sea develops by extension of existing <span class="hlt">continental</span> crust and accretion of new oceanic crust around the margins of a core of Jurassic-Cretaceous oceanic crust that formed and was abandoned within the region as a result of large-scale rotation of the South American <span class="hlt">plate</span> around the northern end of the Antarctic Peninsula in Cretaceous times. The later extension and accretion happened in response to the westwards (since ~50 Ma) and eastwards (since ~17 Ma) motions of southernmost South America and the subduction-related ancestral South Sandwich Trench away from its western and eastern edges. Whilst these events are broadly consistent with what is known about disruption of the biogeographic 'Scotia Portal' in the region, they imply that the onset of Pacific to Atlantic oceanographic connectivity pre-dated, and thus cannot have directly influenced, the onset of Antarctic glaciation.</p> <div class="credits"> <p class="dwt_author">Eagles, Graeme</p> <p class="dwt_publisher"></p> <p class="publishDate">2013-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">334</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/7000731"> <span id="translatedtitle">The Atlantic <span class="hlt">continental</span> margin: US</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The Geology of North America series has been prepared to mark the Centennial of The Geological Society of America. It represents the cooperative efforts of more than 1000 individuals from academia, state and federal agencies of many countries, and industry to prepare syntheses that are as current and authoritative as possible about the geology of the North American continent and adjacent oceanic regions. This series is part of the Decade of North American Geology (DNAG) Project which also includes eight wall maps at a scale of 1:5,000,000 that summarize the geology, tectonics, magnetic and gravity anomaly patterns, regional stress fields, thermal aspects, seismicity and neotectonics of North America and its surroundings. Together, the synthesis volumes and maps are the first coordinated effort to integrate all available knowledge about the geology and geophysics of a crustal <span class="hlt">plate</span> on a regional scale. Topics discussed in Volume 1 include stratigraphy, depositional processes, and depositional history; basin synthesis; deep crystal structure; rifting and subsidence theory; geological resources; and environmental hazards. Individual papers were processed separately for the data base.</p> <div class="credits"> <p class="dwt_author">Sheridan, R.E. (Rutgers--the State Univ., New Brunswick, NJ (USA). Dept. of Geological Sciences); Grow, J.A. (eds.) (Geological Survey, Denver, CO (USA))</p> <p class="dwt_publisher"></p> <p class="publishDate">1988-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">335</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2003EAEJA....13069R"> <span id="translatedtitle">GPS constraints on <span class="hlt">continental</span> deformation in the eastern Mediterranean and Caucasus region</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We use GPS observations during the period 1988 - 2002 to investigate deformation within the zone of interaction of the Eurasian, African, and Arabian <span class="hlt">plates</span>. This region is characterized by a wide variety of tectonic and magmatic processes including a young continent-continent collision (Bitlis-Zagros), lithospheric subduction and associated back-arc spreading (Hellenic and Cyprus trenches, Aegean Sea), <span class="hlt">continental</span>-scale strike slip faults (North Anatolian, East Anatolian, Dead Sea), active mountain building (Caucasus, Zagros), regional-scale extension (Gulf of Corinth, western Turkey), and large-scale tectonic "escape" (Anatolia). We constrain present-day motions of the African (Nubian), Arabian, and Eurasian <span class="hlt">plates</span>, regional deformation within the inter-<span class="hlt">plate</span> zone, and slip rates for major faults. Overall, present-day deformation is for the most part consistent in sense and magnitude with estimates based on neotectonic and paleomagnetic observations covering the past 5 Ma, suggesting that the geodetic results can help constrain dynamic processes that have operated in this region during the most recent geologic period. Kinematically, we interpret the deformation field in terms of a block-like response of the <span class="hlt">continental</span> lithosphere including the westward "escape" of <span class="hlt">continental</span> material away from the Arabia-Eurasia collision zone. The eastern Turkey and Lesser Caucasus region may also exhibit block-like behavior, including counterclockwise rotation that results in increasing rates of convergence from west to east along the Main Caucasus thrust. While most earthquakes are confined to block boundary zones, some have occurred within blocks (e.g., 1988, M=6.9, Spitak, Armenia). These intra-<span class="hlt">plate</span> earthquakes and other neotectonic evidence suggest some internal block deformation, but relative motions within blocks are constrained to be less than 1 - 2 mm/yr, substantially less than the motion between adjacent blocks. In addition to the collision of Arabia with Eurasia, regional deformation appears to be influenced by foundering of the subducting African <span class="hlt">plate</span> along the Hellenic trench that facilitates westward motion of Anatolia. Furthermore, the presence of relatively strong ocean lithosphere beneath the Black and Caspian Seas appears to deflect impinging <span class="hlt">continental</span> lithosphere.</p> <div class="credits"> <p class="dwt_author">Reilinger, R.; McClusky, S.; E. Mediterranean Gps Consortium</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">336</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFMEP53C..04F"> <span id="translatedtitle">Deciphering the history and causes of the cryptic rise and fall of <span class="hlt">continental</span> interiors using low temperature thermochronology</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Low amplitude, long wavelength "epeirogenic" vertical motions in <span class="hlt">continental</span> interiors are not easily explained by <span class="hlt">plate</span> tectonic theory. The extent to which dynamic topography induced by deep mantle buoyancy forces can account for these cryptic <span class="hlt">continental</span> displacements is a subject of increasing study. Testing the vertical motions predicted by mantle dynamic models is challenging, however, because it can be difficult to discriminate between <span class="hlt">continental</span> elevation change and eustatic sea level fluctuations in the geologic record of <span class="hlt">continental</span> interiors. This problem is reflected in a longstanding debate over the relative importance of epeirogeny and eustasy in causing repeated Phanerozoic <span class="hlt">continental</span> flooding and associated deposition of thick sedimentary rock sequences across the cratonic interior of North America. Here we use a new approach to address this problem by applying low temperature thermochronology to exposed Proterozoic and Archean basement samples to better resolve the thermal imprint, thickness, spatial extent, and evolution of missing portions of the Phanerozoic sedimentary record across an ~1300 km region of the western Canadian shield. The sensitivity of apatite (U-Th)/He and fission-track data to 120-30 °C temperatures allows resolution of shallow (1-6 km) depositional and erosional episodes with which to infer subsidence and uplift phases even if the strata associated with those events are no longer preserved in the rock record. The data indicate that a far more extensive region of the continent was inundated in the Paleozoic than is recorded by the rock record, and reveal coherent spatial variability in the thickness and history of the missing Paleozoic sequences. The Paleozoic-Mesozoic history of burial and unroofing recorded by the data does not correlate with eustatic sea level chronologies, and the similarity of depositional and erosional patterns at this <span class="hlt">continental</span> scale in this <span class="hlt">plate</span> interior setting is not easily explained by <span class="hlt">plate</span> margin tectonism. We therefore explore whether dynamic topography provides a viable explanation for these results. A three-dimensional model of thermochemical convection coupled with the <span class="hlt">plate</span> motion history is used to predict the post-400 Ma change in dynamic topography for the western Canadian shield. The predicted history of elevation change compares well with the Paleozoic history of burial and unroofing inferred from the thermochronology data. Burial may be due to cold mantle downwellings that caused subsidence during Pangea assembly, with subsequent unroofing driven by development of warm mantle upwellings after Pangea amalgamation. We conclude that dynamic topography is a plausible first-order cause of long-wavelength elevation change in this <span class="hlt">continental</span> interior. This result demonstrates a new approach for deciphering mantle and surface process interactions deep in Earth history.</p> <div class="credits"> <p class="dwt_author">Flowers, R. M.; Ault, A. K.; Kelley, S.; Zhang, N.; Zhong, S.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">337</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012Sci...335.1334D"> <span id="translatedtitle">A Change in the Geodynamics of <span class="hlt">Continental</span> Growth 3 Billion Years Ago</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Models for the growth of <span class="hlt">continental</span> crust rely on knowing the balance between the generation of new crust and the reworking of old crust throughout Earth’s history. The oxygen isotopic composition of zircons, for which uranium-lead and hafnium isotopic data provide age constraints, is a key archive of crustal reworking. We identified systematic variations in hafnium and oxygen isotopes in zircons of different ages that reveal the relative proportions of reworked crust and of new crust through time. Growth of <span class="hlt">continental</span> crust appears to have been a continuous process, albeit at variable rates. A marked decrease in the rate of crustal growth at ~3 billion years ago may be linked to the onset of subduction-driven <span class="hlt">plate</span> tectonics.</p> <div class="credits"> <p class="dwt_author">Dhuime, Bruno; Hawkesworth, Chris J.; Cawood, Peter A.; Storey, Craig D.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-03-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">338</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/22422979"> <span id="translatedtitle">A change in the geodynamics of <span class="hlt">continental</span> growth 3 billion years ago.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Models for the growth of <span class="hlt">continental</span> crust rely on knowing the balance between the generation of new crust and the reworking of old crust throughout Earth's history. The oxygen isotopic composition of zircons, for which uranium-lead and hafnium isotopic data provide age constraints, is a key archive of crustal reworking. We identified systematic variations in hafnium and oxygen isotopes in zircons of different ages that reveal the relative proportions of reworked crust and of new crust through time. Growth of <span class="hlt">continental</span> crust appears to have been a continuous process, albeit at variable rates. A marked decrease in the rate of crustal growth at ~3 billion years ago may be linked to the onset of subduction-driven <span class="hlt">plate</span> tectonics. PMID:22422979</p> <div class="credits"> <p class="dwt_author">Dhuime, Bruno; Hawkesworth, Chris J; Cawood, Peter A; Storey, Craig D</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-03-16</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">339</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUSMDI74A..04I"> <span id="translatedtitle">Feedback Between Mountain Belt Growth and <span class="hlt">Plate</span> Convergence Revealed by Forward and Inverse Tectonic Models</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">While it is generally assumed that global <span class="hlt">plate</span> motions are driven by the pattern of convection in the Earth's mantle, the details of that linkage remain obscure. Bouyancy forces associated with subduction of cool, dense lithosphere at convergent zones are thought to provide significant driving force, but the relative magnitudes of other driving and resisting forces are less clear. The ability to consider past as well as present <span class="hlt">plate</span> motions provides significant additional constraints, because changes in <span class="hlt">plate</span> motion must be necessarily driven by changes in one or more driving or resisting forces, which may be inferred from independent data. Here we first exploit the capabilities of forward global tectonic models focused on the Andean region to infer <span class="hlt">plate</span> motion changes as far back as Miocene time. By accurately predicting observed convergence rates between Nazca and South America <span class="hlt">plates</span> over the past 10 Myrs, we demonstrate that the topographic load of the Andes increases resistive forces between downgoing and <span class="hlt">overriding</span> <span class="hlt">plates</span> and thus consumes a significant amount of the driving force available for <span class="hlt">plate</span> tectonics. This result suggests a strong feedback between mountain belt growth and <span class="hlt">plate</span> convergence. We then test this notion by performing a numerical inversion of the same model. We use the Automatic Differentiation approach to generate a derivative code that relates convergence of the Nazca/South America <span class="hlt">plates</span> to gross topography of the Andes mountain belt. We test the derivative code in a simple search algorithm to infer an optimal paleotopography of the Andes at 3.2 Myrs from the well-known history of Nazca/South America <span class="hlt">plate</span> convergence. Our modeling result is in good agreement with independent published estimates of Andean paleotopography.</p> <div class="credits"> <p class="dwt_author">Iaffaldano, G.; Buecker, M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-05-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">340</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6685339"> <span id="translatedtitle">Gas hydrates of outer <span class="hlt">continental</span> margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Gas hydrates are crystalline substances in which a rigid framework of water molecules traps molecules of gas, mainly methane. Gas-hydrate deposits are common in <span class="hlt">continental</span> margin sediment in all major oceans at water depths greater than about 300 m. Thirty-three localities with evidence for gas-hydrate occurrence have been described worldwide. The presence of these gas hydrates has been inferred mainly from anomalous lacoustic reflectors seen on marine seismic records. Naturally occurring marine gas hydrates have been sampled and analyzed at about tensites in several regions including <span class="hlt">continental</span> slope and rise sediment of the eastern Pacific Ocean and the Gulf of Mexico. Except for some Gulf of Mexico gas hydrate occurrences, the analyzed gas hydrates are composed almost exclusively of microbial methane. Evidence for the microbial origin of methane in gas hydrates includes (1) the inverse relation between methane occurence and sulfate concentration in the sediment, (2) the subparallel depth trends in carbon isotopic compositions of methane and bicarbonate in the interstitial water, and (3) the general range of {sup 13}C depletion ({delta}{sub PDB}{sup 13}C = {minus}90 to {minus}60 {per thousand}) in the methane. Analyses of gas hydrates from the Peruvian outer <span class="hlt">continental</span> margin in particular illustrate this evidence for microbially generated methane. The total amount of methane in gas hydrates of <span class="hlt">continental</span> margins is not known, but estimates of about 10{sup 16} m{sup 3} seem reasonable. Although this amount of methane is large, it is not yet clear whether methane hydrates of outer <span class="hlt">continental</span> margins will ever be a significant energy resource; however, these gas hydrates will probably constitute a drilling hazard when outer <span class="hlt">continental</span> margins are explored in the future.</p> <div class="credits"> <p class="dwt_author">Kvenvolden, K.A. (Geological Survey, Menlo Park, CA (USA))</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-05-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_16");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a style="font-weight: bold;">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_18");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_17 div --> <div id="page_18" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_17");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a style="font-weight: bold;">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_19");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">341</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6103231"> <span id="translatedtitle">Tectonic evolution of Brazilian equatorial <span class="hlt">continental</span> margin basins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The structural style and stratigraphic relationships of sedimentary basins along the Brazilian Equatorial Atlantic <span class="hlt">Continental</span> Margin were used to construct an empirical tectonic model for the development of ancient transform margins. The model is constrained by detailed structural and subsidence analyses of several basins along the margin. The structural framework of the basins was defined at shallow and deep levels by the integration of many geophysical and geological data sets. The Barreirinhas and Para-Maranhao Basins were divided in three tectonic domains: the Tutoia, Caete, and Tromai subbasins. The Caete area is characterized by northwest-southeast striking and northeast-dipping normal faults. A pure shear mechanism of basin formation is suggested for its development. The structure of the Tutoia and Tromai subbasins are more complex and indicative of a major strike-slip component with dextral sense of displacement, during early stages of basin evolution. These two later subbasins were developed on a lithosphere characterized by an abrupt transition (<50 km wide) from an unstretched continent to an oceanic lithosphere. The subsidence history of these basins do not comply with the classical models developed for passive margins or <span class="hlt">continental</span> rifting. The thermo-mechanical model proposed for the Brazilian equatorial margin includes heterogeneous stretching combined with shearing at the <span class="hlt">plate</span> margin. The tectonic history comprises: (1) Triassic-Jurassic limited extension associated with the Central Atlantic evolution; (2) Neocomian intraplate deformation consisting of strike-slip reactivation of preexisting shear zones; (3) Aptian-Cenomanian two-phase period of dextral shearing; and (4) Late Cretaceous-Cenozoic sea-floor spreading.</p> <div class="credits"> <p class="dwt_author">Azevedo, R.P. (Petrobas, Salvador, Bahia (Brazil))</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-02-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">342</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/43799689"> <span id="translatedtitle">Breakup of Pangaea and <span class="hlt">plate</span> kinematics of the central Atlantic and Atlas regions</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">A new central Pangaea fit (type A) is proposed for the late Ladinian (230 Ma), together with a <span class="hlt">plate</span> motions model for the subsequent phases of rifting, <span class="hlt">continental</span> breakup and initial spreading in the central Atlantic. This model is based on: (1) a reinterpretation of the process of formation of the East Coast Magnetic Anomaly along the eastern margin of</p> <div class="credits"> <p class="dwt_author">Antonio Schettino; Eugenio Turco</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">343</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40426100"> <span id="translatedtitle">Unroofing history of Late Paleozoic magmatic arcs within the “Turan <span class="hlt">Plate</span>” (Tuarkyr, Turkmenistan)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Stratigraphic, sedimentologic and petrographic data collected on the Kizilkaya sedimentary succession (Western Turkmenistan) demonstrate that the “Turan <span class="hlt">Plate</span>” consists in fact of an amalgamation of Late Paleozoic to Triassic <span class="hlt">continental</span> microblocks separated by ocean sutures. In the Kizilkaya area, an ophiolitic sequence including pyroxenite, gabbro, pillow basalt and chert, interpreted as the oceanic crust of a back-arc or intra-arc basin,</p> <div class="credits"> <p class="dwt_author">E. Garzanti; M Gaetani</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">344</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/1660975"> <span id="translatedtitle"><span class="hlt">Plate</span> tectonics and convection in the Earth's mantle: toward a numerical simulation</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Numerical models of mantle convection are starting to reproduce many of the essential features of <span class="hlt">continental</span> drift and <span class="hlt">plate</span> tectonics. The authors show how such methods can integrate a wide variety of geophysical and geological observations. The goal is to combine the Stokes and energy equations with a realistic rheology, thereby letting us understand the complex dynamic coupling that occurs</p> <div class="credits"> <p class="dwt_author">LOUIS MORESI; MICHAEL GURNIS; Shijie Zhong</p> <p class="dwt_publisher"></p> <p class="publishDate">2000-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">345</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.agu.org/journals/jb/v079/i032/JB079i032p04845/JB079i032p04845.pdf"> <span id="translatedtitle">A Model of Convergent <span class="hlt">Plate</span> Margins Based on the Recent Tectonics of Shikoku, Japan</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Displacements generated by a (viscoelastic finite element) <span class="hlt">plate</span> tectonic model are compared with and found to be compatible with geodetic survey data taken on the island of Shikoku, Japan. The model indicates that prior to the 1946 Nankaid0 earthquake, large vertical displacements occurred along the <span class="hlt">continental</span> slope, increasing in magnitude toward and approaching a maximum of 7 m at the</p> <div class="credits"> <p class="dwt_author">Richard Edward Bischke</p> <p class="dwt_publisher"></p> <p class="publishDate">1974-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">346</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://folk.uio.no/torgeir/pdfpapers/eduction.pdf"> <span id="translatedtitle">Subduction and eduction of <span class="hlt">continental</span> crust: major mechanisms during continent-continent collision and orogenic extensional collapse, a model based on the south Norwegian Caledonides</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">During <span class="hlt">continental</span> collision in the middle Silurian, the thickness of the lithosphere under the Caledonides of S. Norway was doubled by subduction of the western margin of Baltica, including the Western Gneiss Region, under Laurentia. Crustal rocks of the Baltic <span class="hlt">plate</span> reached sub- Moho depths of near 100 km or more as inferred from the presence of coesite in eclogites.</p> <div class="credits"> <p class="dwt_author">Torgeir B. Andersen; Bjørn Jamtveit; John F. Dewey; Eivind Swensson</p> <p class="dwt_publisher"></p> <p class="publishDate">1991-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">347</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T13C2228Y"> <span id="translatedtitle">A numerical model of mantle convection with deformable, mobile <span class="hlt">continental</span> lithosphere within three-dimensional spherical geometry</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A new numerical simulation model of mantle convection with a compositionally and rheologically heterogeneous, deformable, mobile <span class="hlt">continental</span> lithosphere is presented for the first time by using three-dimensional regional spherical-shell geometry (Yoshida, 2010, Earth Planet. Sci. Lett.). The numerical results revealed that one of major factor that realizes the supercontinental breakup and subsequent <span class="hlt">continental</span> drift is a pre-existing, weak (low-viscosity) <span class="hlt">continental</span> margin (WCM) in the supercontinent. Characteristic tectonic structures such as young orogenic belts and suture zones in a continent are expected to be mechanically weaker than the stable part of the <span class="hlt">continental</span> lithosphere with the cratonic root (or cratonic lithosphere) and yield lateral viscosity variations in the <span class="hlt">continental</span> lithosphere. In the present-day Earth's lithosphere, the pre-existing, mechanically weak zones emerge as a diffuse <span class="hlt">plate</span> boundary. However, the dynamic role of the WCM in the stability of <span class="hlt">continental</span> lithosphere has not been understood in terms of geophysics. In my numerical model, a compositionally buoyant and highly viscous <span class="hlt">continental</span> assemblage with pre-existing WCMs, analogous to the past supercontinent, is modeled and imposed on well-developed mantle convection whose vigor of convection, internal heating rate, and rheological parameters are appropriate for the Earth's mantle. The visco-plastic oceanic lithosphere and the associated subduction of oceanic <span class="hlt">plates</span> are incorporated. The time integration of the advection of <span class="hlt">continental</span> materials with zero chemical diffusion is performed by a tracer particle method. The time evolution of mantle convection after setting the model supercontinent is followed over 800 Myr. Earth-like <span class="hlt">continental</span> drift is successfully reproduced, and the characteristic thermal interaction between the mantle and the continent/supercontinent is observed in my new numerical model. Results reveal that the WCM protects the cratonic lithosphere from being stretched by the convecting mantle and may play a significant role in the stability of the cratonic lithosphere during the geological timescale because it acts as a buffer that prevents the cratonic lithosphere from undergoing global deformation. From geological evidence that a cratonic root survives at the surface for billions of years, the WCM may have existed in the past supercontinent throughout the Earth's geologic history. The preliminary model presented here should represent an important step toward realizing a more realistic model that could be used to address many outstanding geodynamic problems about the thermal and mechanical feedbacks between the mantle and continents and the temporal evolution of the Earth's mantle structure.</p> <div class="credits"> <p class="dwt_author">Yoshida, M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">348</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..1211149G"> <span id="translatedtitle">New magnetic anomaly map of the East Antarctic <span class="hlt">continental</span> margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Marine magnetic survey coverage of the southern part of Indian Ocean is to a certain extent limited for defining the magnetic pattern of the <span class="hlt">continental</span> margin of East Antarctica. The USA research vessels collected the bulk of the marine magnetic data in the beginning of 1960's. During the succeeding years Australian, German, Japanese, Russian and other international scientific programs made major contributions to the network of marine magnetic data. Since the beginning of new century only two nations (Russian and Australian) have acquired the marine magnetic data in the southern part of Indian Ocean. The marine surveys in the Cosmonaut Sea, the western part of the Cooperation Sea in the Davis and Mawson Seas were accomplished by the PMGRE in 2000-2009 field seasons. The marine magnetic data collected during two seasons (2001-2002) within the AASOPP Project which was established in early 2000 to define the outer limits of the <span class="hlt">continental</span> shelf offshore of the Australian Antarctic Territory (AAT) covered the full length of the AAT from 40OE to 160OE. The new magnetic anomaly map of the East Antarctic <span class="hlt">continental</span> margin incorporates all available data acquired by the international community since the IGY 1957-58 through to 2009. Results of the compilation do not radically alter recent models describing first-order motions between the Antarctic, Australian and Indian <span class="hlt">plates</span>, but they help to resolve uncertainties in early break-up history of opening between these <span class="hlt">plates</span>. The timing and direction of early seafloor spreading in the area off the Antarctic margin, once conjugate to part of the Southern Greater Indian margin and to Australian margin, along the largely unknown region of the Enderby Basin, Davis Sea and Mawson Sea has been analyzed by many authors using different data sets. It is highly likely that spreading in the Enderby Basin occurred around the same time as the well documented M-sequence (anomalies M10 to M0) off the Perth Basin, Western Australia (Powell et al. 1988). The history of the early spreading is complicated further by the likelihood of one or several ridge jumps in which most early seafloor crust was transferred to the Antarctic <span class="hlt">plate</span> and the Elan Bank micro-continent was isolated from the Indian continent (Muller et al. 2001). Additionally, a large amount of the seafloor crust is now probably overprinted by igneous activity associated with the Kerguelen Plume, which began forming the Kerguelen LIP from about 120-110 Ma. However all available results of interpretations do not match to the magnetic anomaly pattern which can be distinguished by the newly compiled map. Our observations suggest that this is especially correct to the Enderby Basin and to lesser degree for the region that was conjugate to Australia. The prominent magnetic anomaly boundary signal and sharp basement step correlated with the MacRobertson Coast Anomaly or the Enderby Basin Anomaly (Golynsky et al., 2007) is not observed elsewhere in the Enderby Basin, Princess Elizabeth Trough or Davis Sea. In the central Enderby Basin there some evidences for an abandoned ‘fossil' spreading centre that might continue to the west of the Kerguelen Plateau, east of Gunnerus Ridge. The estimated timing of its extinction corresponding to the early surface expression of the Kerguelen Plume at the Southern Kerguelen Plateau around 120 Ma and the subsequent formation of the Elan Bank microcontinent. Alternatively, the ridge jump occurred only in the central Enderby basin, due to the proximity of the Kerguelen plateau, whereas seafloor spreading continued in the western Enderby basin and conjugate south of Sri Lanka basin.</p> <div class="credits"> <p class="dwt_author">Golynsky, Alexander; Ivanov, Sergey; Kazankov, Andrey</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">349</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2007jena.confE..79T"> <span id="translatedtitle">WFPDB: European <span class="hlt">Plate</span> Archives</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Wide-Field <span class="hlt">Plate</span> Database (WFPDB) gives an inventory of all wide-field (>~ 1 sq. deg) photographic observations archived in astronomical institutions over the world. So it facilitates and stimulates their use and preservation as a valuable source of information for future investigations in astronomy. At present WFPDB manages <span class="hlt">plate</span>-index information for 25% of all existing <span class="hlt">plates</span> providing on-line access from Sofia (http://www.skyarchive.org/search) and in CDS, Strasbourg. Here we present the new development of WFPDB as an instrument for searching of long term brightness variations of different sky objects stressing on the European photographic <span class="hlt">plate</span> collections (from existing 2 million wide-field <span class="hlt">plates</span> more than 55% are in Europe: Germany, Russia, Ukraine, Italy, Czech Republic, etc.). We comment examples of digitization (with flatbed scanners) of the European <span class="hlt">plate</span> archives in Sonneberg, Pulkovo, Asiago, Byurakan, Bamberg, etc. and virtual links of WFPDB with European AVO, ADS, IBVS.</p> <div class="credits"> <p class="dwt_author">Tsvetkov, Milcho</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-08-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">350</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2002E%26PSL.196...17S"> <span id="translatedtitle">A <span class="hlt">plate</span> tectonic model for the Paleozoic and Mesozoic constrained by dynamic <span class="hlt">plate</span> boundaries and restored synthetic oceanic isochrons</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We developed a <span class="hlt">plate</span> tectonic model for the Paleozoic and Mesozoic (Ordovician to Cretaceous) integrating dynamic <span class="hlt">plate</span> boundaries, <span class="hlt">plate</span> buoyancy, ocean spreading rates and major tectonic and magmatic events. <span class="hlt">Plates</span> were constructed through time by adding/removing oceanic material, symbolized by synthetic isochrons, to major continents and terranes. Driving forces like slab pull and slab buoyancy were used to constrain the evolution of paleo-oceanic domains. This approach offers good control of sea-floor spreading and <span class="hlt">plate</span> kinematics. This new method represents a distinct departure from classical <span class="hlt">continental</span> drift reconstructions, which are not constrained, due to the lack of <span class="hlt">plate</span> boundaries. This model allows a more comprehensive analysis of the development of the Tethyan realm in space and time. In particular, the relationship between the Variscan and the Cimmerian cycles in the Mediterranean-Alpine realm is clearly illustrated by numerous maps. For the Alpine cycle, the relationship between the Alpides senso stricto and the Tethysides is also explicable in terms of <span class="hlt">plate</span> tectonic development of the Alpine Tethys-Atlantic domain versus the NeoTethys domain.</p> <div class="credits"> <p class="dwt_author">Stampfli, G. M.; Borel, G. D.</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-02-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">351</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/visualization/examples/58014.html"> <span id="translatedtitle">Visualizing Earthquakes at Divergent <span class="hlt">Plate</span> Margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This screenshot from the visualization shows both <span class="hlt">continental</span> rift zones, and ocean spreading centers, both types of divergent <span class="hlt">plate</span> boundaries. The visualization shows how earthquakes at all types of divergent margins are shallow and have a low-magnitude. Click the image to enlarge or view the MP4 movie (MP4 Video 79.3MB Aug22 11).The purpose of this activity is to introduce students to the distribution and characteristics of earthquakes associated with divergent <span class="hlt">plate</span> boundaries. Students will learn about how the magnitude and distribution of earthquakes at divergent boundaries are related to processes that occur at these boundaries and to the geometry and position of the two diverging <span class="hlt">plates</span>. Because the depth of earthquakes can be difficult for students to visualize in 2D representations, this activity allows students to visualize the 3D distribution of earthquakes within Earth's surface, which is essential for understanding how different types of earthquakes occur in different tectonic settings. Locations featured in the visualization include the Mid-Atlantic Ridge, the East Pacific Rise, and the East African Rift Zone. Talking points and questions are included to facilitate using this visualization as part of an interactive lecture. In addition to playing back the visualization, instructors can also download the visualization software and data set and explore it themselves.</p> <div class="credits"> <p class="dwt_author">Harwood, Cara</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">352</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/visualization/examples/58013.html"> <span id="translatedtitle">Visualizing Earthquakes at Convergent <span class="hlt">Plate</span> Margins</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This screenshot shows the Fiji subduction zone, one of the featured convergent margins in this visualization. The visualization shows how earthquakes at this margin occur at depth, and define the slope of the subducting <span class="hlt">plate</span>. This visualization also includes other examples of subduction zones and <span class="hlt">continental</span> convergent margins (Himalayas). Click the image to enlarge or view the MP4 movie (MP4 Video 30.3MB Dec20 11). The purpose of this activity is to introduce students to the distribution and characteristics of earthquakes associated with convergent <span class="hlt">plate</span> boundaries. Students will learn about how the magnitude and distribution of earthquakes at convergent boundaries are related to processes that occur at these boundaries and to the geometry and position of the two converging <span class="hlt">plates</span>. Because the depth of earthquakes can be difficult for students to visualize in 2D representations, this activity allows students to visualize the 3D distribution of earthquakes within Earth's surface, which is essential for understanding how different types of earthquakes occur in different tectonic settings. Locations featured in the visualization include the Chile-Peru Subduction Zone, the Aleutian Islands, the Fiji Subeuction Zone, and the Himalayas. Talking points and questions are included to use this visualization as part of an interactive lecture. In addition to playing back the visualization, instructors can also download the visualization software and data set and explore it themselves.</p> <div class="credits"> <p class="dwt_author">Harwood, Cara</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">353</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012EGUGA..1410283F"> <span id="translatedtitle">Evaluating the effect of rheology on the evolution of <span class="hlt">continental</span> collision: Application to the Zagros orogen.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">We explore the impact of thermo-rheological structure of the lithosphere on the transition from oceanic to <span class="hlt">continental</span> subduction and evolution of the <span class="hlt">continental</span> collision at moderate convergence rates. We have designed large-scale (3082×590 km), high-resolution fully coupled thermo-mechanical numerical models to (1) study the evolution of continent-continent collision and (2) draw some parallels with the tectonic evolution of the Zagros, where collision between the Arabian craton and the Eurasian lithosphere resulted in the rise of the Iranian plateau. This collision zone is of particular interest due to its disputed resemblance to the faster Himalayan collision between the Indian craton and Eurasia, which gave birth to the vast Tibetan plateau. Our models implement free upper surface boundary, surface erosion, rheological stratification (upper crust, lower crust, lithospheric mantle and asthenosphere), brittle-elastic-ductile rheology, metamorphic phase changes (density and physical properties), and account for the specific crustal and thermal structure of the Arabian and Iranian <span class="hlt">continental</span> lithospheres. The initial model geometry corresponds to the pre-<span class="hlt">continental</span> collision phase, with an oceanic, Neotethyan subducting lithosphere still separating the two continents. In the experiments we investigate different thermo-rheological structures for both the lower and upper <span class="hlt">plate</span>, going from wet to dry olivine (plus Peierls) rheology for the mantle parts and from two-layer to three-layer crustal structures with all possible granite, diorite, granulate and diabase rheologies. As in some previous Himalayan studies, the experiments suggest that, whatever the crustal rheology, the <span class="hlt">continental</span> subduction occurs only in the case of relatively strong mantle lithospheres with dry olivine rheologies (for the lower <span class="hlt">plate</span>, temperature at Moho depth, Tm < 550° C) and high initial convergence rates (>1.5-5 cm/yr). Depending on the lower-crustal rheology (strong or weak), either the whole (upper and lower) crust or only the lower crust is involved in subduction. In case of weak metamorphic rheologies, phase changes and progressive densification along the subduction zone improve chances for stable subduction. In general, exhumation of UHP-HP rocks to the surface is favored if the crustal rheological profile is characterized by two internal ductile decollement levels (between the upper and lower or intermediate crust and the lower crust and mantle lithosphere). On the other hand, the formation of the Iranian plateau is compatible with the assumption of rather weak mantle and crustal rheology. Hence, the models show that only a relatively narrow range of rheological parameters is compatible with the evolution of Zagros collision, which in turn allows us to further constrain the long-term rheology of the <span class="hlt">continental</span> lithosphere.</p> <div class="credits"> <p class="dwt_author">François, T.; Burov, E.; Agard, P.; Meyer, B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-04-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">354</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17916729"> <span id="translatedtitle">Major Australian-Antarctic <span class="hlt">plate</span> reorganization at Hawaiian-Emperor bend time.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">A marked bend in the Hawaiian-Emperor seamount chain supposedly resulted from a recent major reorganization of the <span class="hlt">plate</span>-mantle system there 50 million years ago. Although alternative mantle-driven and <span class="hlt">plate</span>-shifting hypotheses have been proposed, no contemporaneous circum-Pacific <span class="hlt">plate</span> events have been identified. We report reconstructions for Australia and Antarctica that reveal a major <span class="hlt">plate</span> reorganization between 50 and 53 million years ago. Revised Pacific Ocean sea-floor reconstructions suggest that subduction of the Pacific-Izanagi spreading ridge and subsequent Marianas/Tonga-Kermadec subduction initiation may have been the ultimate causes of these events. Thus, these <span class="hlt">plate</span> reconstructions solve long-standing <span class="hlt">continental</span> fit problems and improve constraints on the motion between East and West Antarctica and global <span class="hlt">plate</span> circuit closure. PMID:17916729</p> <div class="credits"> <p class="dwt_author">Whittaker, J M; Müller, R D; Leitchenkov, G; Stagg, H; Sdrolias, M; Gaina, C; Goncharov, A</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-10-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">355</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5846905"> <span id="translatedtitle">Acceleration of metal <span class="hlt">plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">High-explosive charges have been used to accelerate stainless steel <span class="hlt">plates</span> to velocities of 6-7 km/s. A two-stage system has been used in which the first stage is a plane-wave detonating system that accelerates the <span class="hlt">plate</span> down a short barrel. The second stage consists of a hollow cylindrical charge through which the moving <span class="hlt">plate</span> passes. After an adjustable delay this charge is detonated on the outer circumference of the entry side of the charge. Flash radiographs and witness <span class="hlt">plates</span> show no breakup in the first stage but bowing and frequent breakup in the second stage. 6 figs.</p> <div class="credits"> <p class="dwt_author">Marsh, S.P.; McQueen, R.G.; Tan, T.H.</p> <p class="dwt_publisher"></p> <p class="publishDate">1989-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">356</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.unavco.org/community_science/science-support/crustal_motion/dxdt/model.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Motion Calculator</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This program calculates tectonic <span class="hlt">plate</span> motion at any location on Earth using one or more <span class="hlt">plate</span> motion models. The possible <span class="hlt">plate</span> motion models are GSRM v1.2 (2004), CGPS (2004), HS3-NUVEL1A, REVEL 2000, APKIM2000.0, HS2-NUVEL1A, NUVEL 1A, NUVEL 1, and two models for ITRF2000. <span class="hlt">Plates</span> or frames are selected from dropdown lists or can be entered by the user. Position coordinates can be entered in geographic coordinates (decimal degrees, or degrees/minutes/seconds) or in WGS84 cartesian XYZ, as either a single point or multiple points.</p> <div class="credits"> <p class="dwt_author">Estey, Lou</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">357</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/doepatents/details.jsp?query_id=0&page=0&ostiID=4192376"> <span id="translatedtitle">CALUTRON FACE <span class="hlt">PLATE</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p class="result-summary">The construction of a removable cover <span class="hlt">plate</span> for a calutron tank is described. The <span class="hlt">plate</span> is fabricated of a rectangular frame member to which is welded a bowed or dished <span class="hlt">plate</span> of thin steel, reinforced with transverse stiffening ribs. When the tank is placed between the poles of a magnet, the <span class="hlt">plate</span> may be pivoted away from the tank and magnet and is adapted to support the ion separation mechanism secured to its inner side as well as the vacuum load within the tank.</p> <div class="credits"> <p class="dwt_author">Brobeck, W.M.</p> <p class="dwt_publisher"></p> <p class="publishDate">1959-08-25</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">358</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/6950781"> <span id="translatedtitle">Surface preparation and <span class="hlt">plating</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">This chapter covers electroplating and electroless nickel <span class="hlt">plating</span> since coatings of this type play an important role in diamond turning technology. Items to be discussed include preparation of substrates prior to coating, <span class="hlt">plating</span> defects such as pits and nodules and their influence on optics, the influence of stress in coatings, <span class="hlt">plating</span> details for copper, gold, silver, and electroless nickel, and the importance of additives and their influence on grain size and structure of deposits. Some comments are made on future challenges that could be presented to the <span class="hlt">plating</span> community to further improve the quality of coatings applied for diamond turning purposes. 60 references, 8 figures, 9 tables.</p> <div class="credits"> <p class="dwt_author">Dini, J.W.; Waldrop, F.B.; Reno, R.W.</p> <p class="dwt_publisher"></p> <p class="publishDate">1982-10-06</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">359</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/doepatents/details.jsp?query_id=0&page=0&ostiID=4309469"> <span id="translatedtitle"><span class="hlt">PLATES</span> WITH OXIDE INSERTS</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p class="result-summary">Planar-type fuel assemblies for nuclear reactors are described, particularly those comprising fuel in the oxide form such as thoria and urania. The fuel assembly consists of a plurality of parallel spaced fuel <span class="hlt">plate</span> mennbers having their longitudinal side edges attached to two parallel supporting side <span class="hlt">plates</span>, thereby providing coolant flow channels between the opposite faces of adjacent fuel <span class="hlt">plates</span>. The fuel <span class="hlt">plates</span> are comprised of a plurality of longitudinally extending tubular sections connected by web portions, the tubular sections being filled with a plurality of pellets of the fuel material and the pellets being thermally bonded to the inside of the tubular section by lead.</p> <div class="credits"> <p class="dwt_author">West, J.M.; Schumar, J.F.</p> <p class="dwt_publisher"></p> <p class="publishDate">1958-06-10</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">360</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=N7676745"> <span id="translatedtitle">Mineral Resource Management of the Outer <span class="hlt">Continental</span> Shelf.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">The discussion of the management of the mineral resources of the Outer <span class="hlt">Continental</span> Shelf leads to the following conclusions: The oil and gas production from the Outer <span class="hlt">Continental</span> Shelf represents an increasing percentage of the total United States product...</p> <div class="credits"> <p class="dwt_author">A. E. LaPointe C. B. John M. V. Adams R. F. Kelley R. W. Meurer</p> <p class="dwt_publisher"></p> <p class="publishDate">1976-01-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_17");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a style="font-weight: bold;">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_19");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_18 div --> <div id="page_19" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_18");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a style="font-weight: bold;">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_20");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">361</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=233772"> <span id="translatedtitle">Notice of Release of '<span class="hlt">Continental</span>' Basin Wildrye</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p class="result-summary">'<span class="hlt">Continental</span>' basin wildrye (Leymus cinereus [Scribn. & Merr.] A. Love) has been released as a cultivar for use in rangeland seedings. It was developed from a hybrid between an induced octoploid (2n=56), generated from the natural tetraploid 'Trailhead' (2n=28), and the natural octoploid 'Magnar' (...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">362</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2009CEJG....1..176M"> <span id="translatedtitle"><span class="hlt">Continental</span> and oceanic precipitation régime in Europe</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">This work considers <span class="hlt">continentality</span> from the point of view of an annual course of precipitation. It assesses <span class="hlt">continentality</span> according to percentage of precipitation in summer and winter half year, ratio of precipitation in summer to winter half year and the period of half year precipitation in the area of WMO Region VI (Europe). Region VI can be divided into five main regions according to their annual course of precipitation. These regions are: Northwestern Europe with precipitation in all seasons, a predominance of winter precipitation and maximum precipitation in December and January; Central Europe with precipitation in all seasons, a predominance of summer precipitation and maximum precipitation in July; Eastern Europe with less precipitation over the year than in Northwestern Europe, a predominance of summer precipitation and maximum precipitation in July; the Mediterranean region with a predominance of winter precipitation, a dry season in summer and maximum precipitation in November and December; and Western Asia with a variable climate, a predominance of winter precipitation and maximum precipitation in December and January. <span class="hlt">Continentality</span> from the point of view of precipitation rises towards the east. In comparison with thermal <span class="hlt">continentality</span>, according to Gorczynski, it unexpectedly reaches its maximum in the centre of Europe (especially in northeast of the Czech Republic and south of Poland).</p> <div class="credits"> <p class="dwt_author">Mikolaskova, Katerina</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">363</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/42010189"> <span id="translatedtitle"><span class="hlt">Continental</span> thermal isostasy: 1. Methods and sensitivity</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary"><span class="hlt">Continental</span> elevations result from a combination of compositional and thermal buoyancy and geodynamic forces. Thermal effects are often masked by compositional variations to crustal density and thickness that produce equal or greater relief. We have developed a method by which compositional variations in the crust may be removed, thereby isolating the thermal contribution to elevation. This isostatic correction normalizes the</p> <div class="credits"> <p class="dwt_author">Derrick Hasterok; David S. Chapman</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">364</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17741070"> <span id="translatedtitle">Elephant teeth from the atlantic <span class="hlt">continental</span> shelf.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Teeth of mastodons and mammoths have been recovered by fishermen from at least 40 sites on the <span class="hlt">continental</span> shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, anz relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25,000 years. PMID:17741070</p> <div class="credits"> <p class="dwt_author">Whitmore, F C; Emery, K O; Cooke, H B; Swift, D J</p> <p class="dwt_publisher"></p> <p class="publishDate">1967-06-16</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">365</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ntis.gov/search/product.aspx?ABBR=DE98751569"> <span id="translatedtitle">Discoveries on the Norwegian <span class="hlt">continental</span> shelf.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ntis.gov/search/index.aspx">National Technical Information Service (NTIS)</a></p> <p class="result-summary">As discussed in this document, there are 108 discoveries on the Norwegian <span class="hlt">continental</span> shelf which so far have not been approved for development. The oil and gas resources of the Norwegian Sea and the Barents Sea are mostly found in discoveries containing ...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">1997-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">366</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/54165898"> <span id="translatedtitle"><span class="hlt">Continental</span> water storage variations in Africa</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We investigate temporal and spatial variations of <span class="hlt">continental</span> water storage in Africa as recovered by the GRACE (Gravity Recovery and Climate Experiment) mission. Mass variations are directly inverted from only KBRR (K-band range rate) data using a mascon approach. We compare our solutions to classical spherical harmonic solutions and also to different global hydrology models, and regional models in the</p> <div class="credits"> <p class="dwt_author">Jean-Paul Boy; Claudia Carabajal; Scott Luthcke; David Rowlands; Frank Lemoine; Terence Sabaka</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">367</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52180181"> <span id="translatedtitle"><span class="hlt">Continental</span> water storage variations in Africa</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">We investigate the temporal and spatial variations of <span class="hlt">continental</span> water storage in Africa as recovered by the NASA\\/DLR Gravity Recovery and Climate Experiment (GRACE) mission. Mass variations are directly inverted from the K-band range rate using the mascon approach. We compare our solution to global different hydrological models. We solve the water mass balance equation, using different precipitation datasets from</p> <div class="credits"> <p class="dwt_author">J. Boy; C. C. Carabajal; S. B. Luthcke; D. D. Rowlands; F. G. Lemoine; T. J. Sabaka</p> <p class="dwt_publisher"></p> <p class="publishDate">2009-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">368</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.cmos.ca/Ao/articles/v210206.pdf"> <span id="translatedtitle">Circulation on the newfoundland <span class="hlt">continental</span> shelf</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The circulation on the Newfoundland <span class="hlt">Continental</span> Shelf derived from a review of different data sources generally agrees with the classical description of the flow in this area given by Smith et al. (1937). Hydrological, surface and bottom drifter, satellite?tracked buoy, ships drift, current meter and sea?level observations are used to estimate mean flows, transports, and fluctuating currents and to define</p> <div class="credits"> <p class="dwt_author">Brian Petrie; Carl Anderson</p> <p class="dwt_publisher"></p> <p class="publishDate">1983-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">369</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/40562865"> <span id="translatedtitle">Two long geological records of <span class="hlt">continental</span> ecosystems</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The early Paleogene <span class="hlt">continental</span> sequence of northwestern Wyoming and south central Montana (USA) and the Neogene Siwalik sequence of northern Pakistan are exceptionally long, fossiliferous, and well studied in terms of geology, paleontology, mammalian evolution, paleoecology, and paleoclimatology. Each record spans about 15 myr of alluvial deposition in a foreland basin. The fluvial systems differed in size, drainage of floodplains,</p> <div class="credits"> <p class="dwt_author">Catherine Badgley; Anna K. Behrensmeyer</p> <p class="dwt_publisher"></p> <p class="publishDate">1995-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">370</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/14993325"> <span id="translatedtitle">Do the Pyramids Show <span class="hlt">Continental</span> Drift?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The mystery of the orientation of the Great Pyramids of Giza has remained unexplained for many decades. The general alignment is 4 minutes west of north. It is argued that this is not a builders' error but is caused by movement over the centuries. Modern theories of <span class="hlt">continental</span> drift do not predict quite such large movements, but other causes of</p> <div class="credits"> <p class="dwt_author">G. S. Pawley; N. Abrahamsen</p> <p class="dwt_publisher"></p> <p class="publishDate">1973-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">371</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/19902820"> <span id="translatedtitle">Lithosphere Deformation by <span class="hlt">Continental</span> Ice Sheets</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">In treating problems of mantle deformation, a common assumption of convenience is that deformation is viscous or viscoelastic. An important consequence of this assumption is the unproven prediction that the lithosphere is depressed far beyond the margins of steady-state <span class="hlt">continental</span> ice sheets at the time of their maximum extent. Depression beyond the margins of shrinking ice sheets is proven by</p> <div class="credits"> <p class="dwt_author">T. Hughes</p> <p class="dwt_publisher"></p> <p class="publishDate">1981-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">372</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/52291834"> <span id="translatedtitle">Elephant Teeth from the Atlantic <span class="hlt">Continental</span> Shelf</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Teeth of mastodons and mammoths have been recovered by fishermen from at least 40 sites on the <span class="hlt">continental</span> shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, and relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25,000 years.</p> <div class="credits"> <p class="dwt_author">Frank C. Whitmore Jr.; K. O. Emery; H. B. S. Cooke; Donald J. P. Swift</p> <p class="dwt_publisher"></p> <p class="publishDate">1967-01-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">373</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.geohazards.buffalo.edu/documents/ValentineandGregg2008.pdf"> <span id="translatedtitle"><span class="hlt">Continental</span> basaltic volcanoes — Processes and problems</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">Monogenetic basaltic volcanoes are the most common volcanic landforms on the continents. They encompass a range of morphologies from small pyroclastic constructs to larger shields and reflect a wide range of eruptive processes. This paper reviews physical volcanological aspects of <span class="hlt">continental</span> basaltic eruptions that are driven primarily by magmatic volatiles. Explosive eruption styles include Hawaiian and Strombolian (sensu stricto) and</p> <div class="credits"> <p class="dwt_author">G. A. Valentine; T. K. P. Gregg</p> <p class="dwt_publisher"></p> <p class="publishDate">2008-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">374</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2012IJEaS.tmp...62V"> <span id="translatedtitle">Morphology and geology of the <span class="hlt">continental</span> shelf and upper slope of southern Central Chile (33°S-43°S)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The <span class="hlt">continental</span> shelf and slope of southern Central Chile have been subject to a number of international as well as Chilean research campaigns over the last 30 years. This work summarizes the geologic setting of the southern Central Chilean <span class="hlt">Continental</span> shelf (33°S-43°S) using recently published geophysical, seismological, sedimentological and bio-geochemical data. Additionally, unpublished data such as reflection seismic profiles, swath bathymetry and observations on biota that allow further insights into the evolution of this <span class="hlt">continental</span> platform are integrated. The outcome is an overview of the current knowledge about the geology of the southern Central Chilean shelf and upper slope. We observe both patches of reduced as well as high recent sedimentation on the shelf and upper slope, due to local redistribution of fluvial input, mainly governed by bottom currents and submarine canyons and highly productive upwelling zones. Shelf basins show highly variable thickness of Oligocene-Quaternary sedimentary units that are dissected by the marine continuations of upper <span class="hlt">plate</span> faults known from land. Seismic velocity studies indicate that a paleo-accretionary complex that is sandwiched between the present, relatively small active accretionary prism and the <span class="hlt">continental</span> crust forms the bulk of the <span class="hlt">continental</span> margin of southern Central Chile.</p> <div class="credits"> <p class="dwt_author">Völker, David; Geersen, Jacob; Contreras-Reyes, Eduardo; Sellanes, Javier; Pantoja, Silvio; Rabbel, Wolfgang; Thorwart, Martin; Reichert, Christian; Block, Martin; Weinrebe, Wilhelm Reimer</p> <p class="dwt_publisher"></p> <p class="publishDate">2012-06-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">375</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/FR-2013-05-29/pdf/2013-12679.pdf"> <span id="translatedtitle">78 FR 32183 - Importation of Avocados From <span class="hlt">Continental</span> Spain</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013</a></p> <p class="result-summary">...APHIS-2012-0002] RIN 0579-AD63 Importation of Avocados From <span class="hlt">Continental</span> Spain AGENCY: Animal...rule that would allow the importation of avocados from <span class="hlt">continental</span> Spain (excluding the...regulations to allow the importation of avocados from <span class="hlt">continental</span> Spain (excluding...</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2013-05-29</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">376</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.math.montana.edu/%7Enmp/materials/ess/geosphere/inter/activities/plate_calc/index.html"> <span id="translatedtitle">The Moving <span class="hlt">Plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This lesson focuses on relative versus absolute velocity. Students can use a program (must be connected to the internet) to calculate the different types of velocities for different points along <span class="hlt">plate</span> boundaries. A very brief description of the earth's <span class="hlt">plates</span> is given, with links to additional information and images. Includes discussion questions.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">377</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://academic.research.microsoft.com/Publication/59185534"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics with GIS</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p class="result-summary">The concept of <span class="hlt">Plate</span> Tectonics involves piecing together a wide variety of evidence to build a picture. This includes the location of earthquakes, volcanoes, mountains, fossils, and other paleoclimate data. The theory of <span class="hlt">Plate</span> Tectonics is driven by information that is attached to a location. Even further, the theory is driven by looking and analyzing all these pieces of information</p> <div class="credits"> <p class="dwt_author">Nate Ruder</p> <p class="dwt_publisher"></p> <p class="publishDate">2006-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">378</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.windows.ucar.edu/tour/link=/earth/interior/how_plates_move.html"> <span id="translatedtitle">How Do <span class="hlt">Plates</span> Move?</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">The representation shows the circulation of convection cells in the mantle related to <span class="hlt">plate</span> movement. A static cross-sectional diagram and accompanying text illustrates the how material heated by the core rises and then sinks when it eventually cools down and attributes this cycle of heating and cooling to tectonic <span class="hlt">plate</span> movement.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">379</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFMPP42A..05J"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics and Terrestrial Carbon Isotope Records</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">In 2001, we reported a negative excursion in early-Aptian atmospheric ?13CO2 (? = -3.6 to -6.5‰), based on ?13C analyses of organic matter and land-plant isolates from coarsely-sampled Colombian estuarine and near-shore sediments. Here we present similar results for an Aptian section of the Arundel Clay (Potomac Group, central Maryland), which is well-known for its exceptional preservation of terrestrial plant materials. Sampling across 13 meters of sediment at ~10-cm intervals revealed a clear shift in the ?13C of terrestrial organic matter (n=153) and land-plant isolates (n=33) of ? = -2.3 and -2.9 ‰, respectively. The shift was observed within palynological Zone I, which is temporally well-correlated with our previous work. Using an empirical relationship between ?13Cplant and ?13Catm, we calculated ??13Catm = -2.1 to -2.6 ‰ during the early Aptian from the Arundel Clay shift. Given the probable composition of the early Cretaceous atmosphere, mass balance calculations favor a methane hydrate release as the cause of this excursion. In consideration of a mechanism for methane release, we calculated changes in global subduction indicated by the well-established and rapid 2-fold increase in seafloor production that was unique within the early Aptian compared to the last 144 million years. We show that increased frictional interaction between <span class="hlt">overriding</span> and subducting <span class="hlt">plates</span> caused uplift and compression sufficient to continuously destabilize a portion of the probable methane hydrate reservoir, thus creating a perturbation in the C-isotope record of the Aptian atmosphere, as reflected in the ?13C of terrestrial photosynthesizers. The Aptian methane release is a new example of mechanistic coupling between major tectonic events and the global biosphere.</p> <div class="credits"> <p class="dwt_author">Jahren, H.; Conrad, C.; Arens, N.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">380</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFM.T14C..04D"> <span id="translatedtitle">Episodic vs. Continuous Accretion in the Franciscan Accretionary Prism and Direct <span class="hlt">Plate</span> Motion Controls vs. More Local Tectonic Controls on Prism Evolution</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Subduction at the Franciscan trench began ?170-165 Ma and continues today off Oregon-Washington. <span class="hlt">Plate</span> motion reconstructions, high-P metamorphic rocks, and the arc magmatic record suggest that convergence and thus subduction were continuous throughout this period, although data for 170 to 120 Ma are less definitive. About 25% of modern subduction zones are actively building an accretionary prism, whereas 75% are nonaccretionary, in which subduction erosion is gradually removing the prism and/or forearc basement. These contrasting behaviors in modern subduction zones suggest that the Franciscan probably fluctuated between accretionary and nonaccretionary modes at various times and places during its 170 million year lifespan. Accumulating geochronologic data are beginning to clarify certain accretionary vs. nonaccretionary intervals. (1) The oldest Franciscan rocks are high-P mafic blocks probably metamorphosed in a subophiolitic sole during initiation of subduction. They yield garnet Lu-Hf and hornblende Ar/Ar ages from ?169 to 147 Ma. Their combined volume is extremely small and much of the Franciscan was probably in an essentially nonaccretionary mode during this period. (2) The South Fork Mountain Schist forms the structural top of the preserved wedge in northern California and thus was apparently the first genuinely large sedimentary body to accrete. This occurred at ?123 Ma (Ar/Ar ages), suggesting major accretion was delayed a full ?45 million years after the initiation of subduction. The underlying Valentine Spring Fm. accreted soon thereafter. This shift into an accretionary mode was nearly synchronous with the end of the Early Cretaceous magmatic lull and the beginning of the prolonged Cretaceous intensification of magmatism in the Sierra Nevada arc. (3) The Yolla Bolly terrane has generally been assigned a latest Jurassic to earliest Cretaceous age. Detrital zircon data confirm that some latest Jurassic sandstones are present, but they may be blocks in olistotromes and the bulk of the terrane may be mid-Cretaceous trench sediments. (4) New data from the Central mélange belt are pending. (5) Detrital zircon ages suggest much of the voluminous Coastal belt was deposited in a short, rapid surge in the Middle Eocene, coincident with major extension, core complex development, volcanism, and erosion in sediment source areas in Idaho-Montana. Rapid Tyee Fm deposition in coastal Oregon occurred at virtually the same time from the same sources. (6) Exposed post-Eocene Franciscan rocks are rare. It is tempting to ascribe subduction zone tectonic events directly to changes in relative motions between the subducting and <span class="hlt">overriding</span> lithospheric <span class="hlt">plates</span>. However, in modern subduction zones, varying sediment supply to the trench appears to be a more important control on accretionary prism evolution and this seems to be the case in the Franciscan as well. Franciscan accretion was apparently influenced primarily by complex <span class="hlt">continental</span> interior tectonics controlling sediment supply from the North American Cordillera (which may in part reflect <span class="hlt">plate</span> motion changes), rather than directly by changes in the motions of tectonic <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Dumitru, T. A.; Ernst, W. G.; Wakabayashi, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2011-12-01</p> </div> </div> </div> </div> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_18");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a style="font-weight: bold;">19</a> <a onClick='return showDiv("page_20");' href="#">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_20");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> </div><!-- page_19 div --> <div id="page_20" class="hiddenDiv"> <div id="filter_results_form" class="filter_results_form floatContainer" style="visibility: visible;"> <div style="width:100%" id="PaginatedNavigation" class="paginatedNavigationElement"> <a id="FirstPageLink" onclick='return showDiv("page_1");' href="#" title="First Page"> <img id="FirstPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.first.18x20.png" alt="First Page" /></a> <a id="PreviousPageLink" onclick='return showDiv("page_19");' href="#" title="Previous Page"> <img id="PreviousPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.previous.18x20.png" alt="Previous Page" /></a> <span id="PageLinks" class="pageLinks"> <span> <a onClick='return showDiv("page_1");' href="#">1</a> <a onClick='return showDiv("page_2");' href="#">2</a> <a onClick='return showDiv("page_3");' href="#">3</a> <a onClick='return showDiv("page_4");' href="#">4</a> <a onClick='return showDiv("page_5");' href="#">5</a> <a onClick='return showDiv("page_6");' href="#">6</a> <a onClick='return showDiv("page_7");' href="#">7</a> <a onClick='return showDiv("page_8");' href="#">8</a> <a onClick='return showDiv("page_9");' href="#">9</a> <a onClick='return showDiv("page_10");' href="#">10</a> <a onClick='return showDiv("page_11");' href="#">11</a> <a onClick='return showDiv("page_12");' href="#">12</a> <a onClick='return showDiv("page_13");' href="#">13</a> <a onClick='return showDiv("page_14");' href="#">14</a> <a onClick='return showDiv("page_15");' href="#">15</a> <a onClick='return showDiv("page_16");' href="#">16</a> <a onClick='return showDiv("page_17");' href="#">17</a> <a onClick='return showDiv("page_18");' href="#">18</a> <a onClick='return showDiv("page_19");' href="#">19</a> <a style="font-weight: bold;">20</a> <a onClick='return showDiv("page_21");' href="#">21</a> <a onClick='return showDiv("page_22");' href="#">22</a> <a onClick='return showDiv("page_23");' href="#">23</a> <a onClick='return showDiv("page_24");' href="#">24</a> <a onClick='return showDiv("page_25");' href="#">25</a> </span> </span> <a id="NextPageLink" onclick='return showDiv("page_21");' href="#" title="Next Page"> <img id="NextPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.next.18x20.png" alt="Next Page" /></a> <a id="LastPageLink" onclick='return showDiv("page_25.0");' href="#" title="Last Page"> <img id="LastPageLinkImage" class="Icon" src="http://www.science.gov/scigov/images/icon.last.18x20.png" alt="Last Page" /></a> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">381</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://web.ics.purdue.edu/~braile/edumod/flipbook/flipbook.htm"> <span id="translatedtitle">Voyage Through Time: <span class="hlt">Plate</span> Tectonics Flipbook</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This activity will enable students to view the breakup of the super-continent Pangaea over the past 190 million years and chart the subsequent movement of land masses, and to better understand <span class="hlt">plate</span> tectonics. Students are provided with copies of map sheets with frames which are reconstructed maps of the land masses that existed on Earth at a specific time. Beginning with frame 20 and working backwards students identify the land masses listed in an available table. By assigning different land masses to different groups, the students will be able to share their results when the flipbooks are completed and several different <span class="hlt">continental</span> movements and tectonic interactions will be illustrated on the different flipbooks. All required maps and tables are provided at this site.</p> <div class="credits"> <p class="dwt_author">Braile, Larry; Braile, Sheryl</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">382</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5883610"> <span id="translatedtitle">Sizing <span class="hlt">plate</span> heat exchangers</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Since their commercial debut in the 1930s, <span class="hlt">plate</span> heat exchangers have found widespread use in the chemical process industries (CPI). Today, more than two dozen firms market this space-saving and highly efficient type of heat exchanger. One reason for the popularity of <span class="hlt">plate</span> heat exchangers is that their overall heat-transfer coefficient (U) is superior to that of shell-and-tube heat exchangers [1,2,3,4]. In clean water-to-water service, for example, a shell-and-tube heat exchanger has a U value of 350 Btu/ft[sup 2]-h-F, much lower than the 1,000 of a <span class="hlt">plate</span> design at the same pressure drop. However, the <span class="hlt">plate</span> heat exchanger's much higher U values also mean that fouling factors have a much greater effect on calculations of exchanger surface area. The right fouling factor is the key to specifying <span class="hlt">plate</span> heat exchanger areas correctly.</p> <div class="credits"> <p class="dwt_author">Kerner, J. (Alberts and Associates, Inc., Philadelphia, PA (United States))</p> <p class="dwt_publisher"></p> <p class="publishDate">1993-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">383</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFMGP43C..03M"> <span id="translatedtitle">The Seismicity and Crustal Structure of <span class="hlt">Continental</span> Eastern Russia</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Regional networks were established under the Former Soviet Union to monitor seismic activity and evaluate seismic hazards. In eastern Russia, these networks were deployed starting in the early 1960s. The networks generally operated analog short-period instruments, with some base stations having long-period sensors. Approximately 50,000 events have been located on the <span class="hlt">continental</span> part of eastern Russia. These earthquakes define the boundaries between three major (Pacific, North America, Eurasia), and several minor (Bering, Okhotsk, Amur, Primoria) <span class="hlt">plates</span>. The zones of seismic activity are diffuse and indicate that deformation between these <span class="hlt">plates</span> is distributed over a large number of faults. Major strike-slip faults can be identified both by linear trends in the larger seismicity and in satellite imagery; examples include the Ulakhan fault system, between North America and Okhotsk, the Ketanda fault system between Okhotsk and Eurasia, and a system of faults in southern Yakutia and the Stanovoi Range between Eurasia and Amur. Regional arrivals at Russian seismic stations were used to determine crustal P- and S-wave velocities. A grid search method conducted along a moving window through eastern Russia to find best-fit velocities for minimizing travel-time residuals yields a model that is consistent with the tectonic setting (cratons, rift zones). Preliminary ground-truth experiments in the Magadan district show a good fit between the determined best-fit velocities and those from industrial explosions, as do those from previous Russian seismic surveys. Earthquake relocations using these best-fit velocities, and combining data from between networks, reveal linear trends and clusters which can be associated with active faults. Considerable contamination of the Russian seismicity catalog by industrial explosions has also occurred.</p> <div class="credits"> <p class="dwt_author">Mackey, K. G.; Nichols, M. L.; Fujita, K.; Gounbina, L. V.; Koz'min, B. M.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">384</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2001AGUFM.T51C0892D"> <span id="translatedtitle">Ophiolites and <span class="hlt">Continental</span> Margins of the Mesozoic Western U.S. Cordillera</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The Mesozoic tectonic history of the western U.S. Cordillera records evidence for multiple episodes of accretionary and collisional orogenic events and orogen-parallel strike-slip faulting. Paleozoic-Jurassic volcanic arc complexes and subduction zone assemblages extending from Mexico to Canada represent an East-Pacific magmatic arc system and an accretionary-type orogen evolved along the North American <span class="hlt">continental</span> margin. Discontinuous exposures of Paleozoic upper mantle rocks and ophiolitic units structurally beneath this magmatic arc system are remnants of the Panthalassan oceanic lithosphere, which was consumed beneath the North American continent. Pieces of this subducted Panthalassan oceanic lithosphere that underwent high-P metamorphism are locally exposed in the Sierra Nevada foothills (e.g. Feather River Peridotite) indicating that they were subsequently (during the Jurassic) educted in an oblique convergent zone along the <span class="hlt">continental</span> margin. This west-facing <span class="hlt">continental</span> margin arc evolved in a broad graben system during much of the Jurassic as a result of extension in the upper <span class="hlt">plate</span>, keeping pace with slab rollback of the east-dipping subduction zone. Lower to Middle Jurassic volcanoplutonic complexes underlain by an Upper Paleozoic-Lower Mesozoic polygenetic ophiolitic basement currently extend from Baja California-western Mexico through the Sierra-Klamath terranes to Stikinia-Intermontane Superterranes in Canada and represent an archipelago of an east-facing ensimatic arc terrane that developed west and outboard of the North American <span class="hlt">continental</span> margin arc. The Smartville, Great Valley, and Coast Range ophiolites (S-GV-CR) in northern California are part of this ensimatic terrane and represent the island arc, arc basement, and back-arc tectonic settings, respectively. The oceanic Josephine-Rogue-Chetco-Rattlesnake-Hayfork tectonostratigraphic units in the Klamath Mountains constitute a west-facing island arc system in this ensimatic terrane as a counterpart of the east-facing S-GV-CR system to the south. The Guerrero intra-oceanic island arc system in Mexico was also part of the ensimatic arc terrane. Incorporation of this super arc terrane into the North American continent occurred diachronously along the irregular <span class="hlt">continental</span> margin in the Middle Jurassic (in the north) through Early Cretaceous (in the south) during an arc-continent collision, marking a collisional orogenic episode in the North American Cordilleran history. Rifting of this accreted arc in the Late Jurassic (155-148 Ma) might have resulted from a sinistral transtensional deformation associated with the rapid NW motion of North America. Magmas generated during this rifting event probably migrated through the accreted arc crust and the <span class="hlt">continental</span> margin units in the tectonic lower <span class="hlt">plate</span>. The Franciscan subduction zone dipping eastwards beneath the continent was established in the latest Jurassic, following the collisional event and restoring the North American Cordillera back into an accretionary-type, Andean-style orogen. Different episodes of orogen-parallel intra-<span class="hlt">continental</span> strike-slip faulting facilitated lateral dispersion of accreted terranes and <span class="hlt">continental</span> margin units during the Early Cretaceous and transpressional deformation and batholithic magmatism in the Sierra Nevada magmatic arc in the Late Cretaceous. A Jurassic-Cretaceous island arc system (Wrangellia-Insular Superterrane) that had developed west of the Jurassic archipelago collapsed into the edge of North America during Late Cretaceous-Tertiary time and underwent northward lateral translation along the <span class="hlt">continental</span> margin. These observations and interpretations have strong implications for the tectonic evolution of Central America and the Caribbean region.</p> <div class="credits"> <p class="dwt_author">Dilek, Y.</p> <p class="dwt_publisher"></p> <p class="publishDate">2001-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">385</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://dx.doi.org/10.1016/j.epsl.2007.09.025"> <span id="translatedtitle">Petrology and tectonics of Phanerozoic continent formation: From island arcs to accretion and <span class="hlt">continental</span> arc magmatism</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p class="result-summary">Mesozoic <span class="hlt">continental</span> arcs in the North American Cordillera were examined here to establish a baseline model for Phanerozoic continent formation. We combine new trace-element data on lower crustal xenoliths from the Mesozoic Sierra Nevada Batholith with an extensive grid-based geochemical map of the Peninsular Ranges Batholith, the southern equivalent of the Sierras. Collectively, these observations give a three-dimensional view of the crust, which permits the petrogenesis and tectonics of Phanerozoic crust formation to be linked in space and time. Subduction of the Farallon <span class="hlt">plate</span> beneath North America during the Triassic to early Cretaceous was characterized by trench retreat and slab rollback because old and cold oceanic lithosphere was being subducted. This generated an extensional subduction zone, which created fringing island arcs just off the Paleozoic <span class="hlt">continental</span> margin. However, as the age of the Farallon <span class="hlt">plate</span> at the time of subduction decreased, the extensional environment waned, allowing the fringing island arc to accrete onto the <span class="hlt">continental</span> margin. With continued subduction, a <span class="hlt">continental</span> arc was born and a progressively more compressional environment developed as the age of subducting slab continued to young. Refinement into a felsic crust occurred after accretion, that is, during the <span class="hlt">continental</span> arc stage, wherein a thickened crustal and lithospheric column permitted a longer differentiation column. New basaltic arc magmas underplate and intrude the accreted terrane, suture, and former <span class="hlt">continental</span> margin. Interaction of these basaltic magmas with pre-existing crust and lithospheric mantle created garnet pyroxenitic mafic cumulates by fractional crystallization at depth as well as gabbroic and garnet pyroxenitic restites at shallower levels by melting of pre-existing lower crust. The complementary felsic plutons formed by these deep-seated differentiation processes rose into the upper crust, stitching together the accreted terrane, suture and former <span class="hlt">continental</span> margin. The mafic cumulates and restites, owing to their high densities, eventually foundered into the mantle, leaving behind a more felsic crust. Our grid-based sampling allows us to estimate an unbiased average upper crustal composition for the Peninsular Ranges Batholith. Major and trace-element compositions are very similar to global <span class="hlt">continental</span> crust averaged over space and time, but in detail, the Peninsular Ranges are slightly lower in compatible to mildly incompatible elements, MgO, Mg#, V, Sc, Co, and Cr. The compositional similarities suggest a strong arc component in global <span class="hlt">continental</span> crust, but the slight discrepancies suggest that additional crust formation processes are also important in continent formation as a whole. Finally, the delaminated Sierran garnet pyroxenites have some of the lowest U/Pb ratios ever measured for silicate rocks. Such material, if recycled and stored in the deep mantle, would generate a reservoir with very unradiogenic Pb, providing one solution to the global Pb isotope paradox. ?? 2007 Elsevier B.V. All rights reserved.</p> <div class="credits"> <p class="dwt_author">Lee, C. -T. A.; Morton, D. M.; Kistler, R. W.; Baird, A. K.</p> <p class="dwt_publisher"></p> <p class="publishDate">2007-01-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">386</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010JGRB..115.5306R"> <span id="translatedtitle">USArray observations of quasi-Love surface wave scattering: Orienting anisotropy in the Cascadia <span class="hlt">plate</span> boundary</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Quasi-Love (QL) surface wave anomalies are observed along multiple great circle paths crossing the Pacific and through the mid-ocean ridge and subduction zone associated with the Juan de Fuca <span class="hlt">plate</span>. The long-period QL waves observed on the USArray component of EarthScope arrive immediately after the fundamental Love wave arrival, suggesting that the QL waves were generated close to USArray and near the <span class="hlt">plate</span> boundary. The dense USArray network allows the analysis of the azimuthal dependence of the QL surface wave scattering to determine the horizontal anisotropic axes of symmetry in Earth's upper mantle. We focus on the location, 42.5°N and 127.5°W just offshore of the southern Oregon coastline near the Gorda Ridge, and we analyze the QL scattering along 14 different great circle paths crossing through this location. We low-pass filter the data to suppress overtones and crustal effects. QL amplitude and polarity constrains an anisotropic axis of symmetry that correlates well with the hot spot referenced Juan de Fuca <span class="hlt">plate</span> motion and regional shear wave splitting. QL observations at multiple periods (50, 75, 100, 150, and 200 s) suggest a maximum Love-to-Rayleigh scattering at 100 s period, which is consistent with anisotropic lateral gradients in the asthenosphere beneath the Juan de Fuca and Gorda <span class="hlt">plates</span>. Our observations do not follow the predictions of slab rollback and suggest the entrainment of asthenosphere with the <span class="hlt">overriding</span> Juan de Fuca and Gorda <span class="hlt">plates</span>.</p> <div class="credits"> <p class="dwt_author">Rieger, D. M.; Park, J.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-05-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">387</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.pbs.org/wgbh/aso/tryit/tectonics/intro.html"> <span id="translatedtitle">Intro to <span class="hlt">Plate</span> Tectonic Theory</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This website from PBS provides information about the <span class="hlt">plate</span> tectonics, the theory that the Earth's outer layer is made up of <span class="hlt">plates</span>, which have moved throughout time. The four types of <span class="hlt">plate</span> boundaries are described and illustrated with animations. The first page of <span class="hlt">plate</span> tectonics also provides a <span class="hlt">plate</span> tectonics activity and information about related people and discoveries.</p> <div class="credits"> <p class="dwt_author"></p> <p class="dwt_publisher"></p> <p class="publishDate">2008-05-28</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">388</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/146023"> <span id="translatedtitle">Paleozoic <span class="hlt">plate</span>-tectonic evolution of the Tarim and western Tianshan regions, western China</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">The <span class="hlt">plate</span>-tectonic evolution of the Tarim basin and nearby western Tianshan region during Paleozoic time is reconstructed in an effort to further constrain the tectonic evolution of Central Asia, providing insights into the formation and distribution of oil and gas resources. The Tarim <span class="hlt">plate</span> developed from <span class="hlt">continental</span> rifting that progressed during early Paleozoic time into a passive <span class="hlt">continental</span> margin. The Yili terrane (central Tianshan) broke away from the present eastern part of Tarim and became a microcontinent located somewhere between the Junggar ocean and the southern Tianshan ocean. The southern Tianshan ocean, between the Tarim craton and the Yili terrane, was subducting beneath the Yili terrane from Silurian to Devonian time. During the Late Devonian-Early Carboniferous, the Tarim <span class="hlt">plate</span> collided with the Yili terrane by sinistral accretional docking that resulted in a late Paleozoic deformational episode. Intracontinental shortening (A-type subduction) continued through the Permian with the creation of a magmatic belt. 21 refs., 7 figs., 1 tab.</p> <div class="credits"> <p class="dwt_author">Yangshen, S.; Huafu, L.; Dong, J. [Nanjing Univ. (China)] [and others</p> <p class="dwt_publisher"></p> <p class="publishDate">1994-11-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">389</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2002AGUFM.S11A1099H"> <span id="translatedtitle">Plumes do not Exist: <span class="hlt">Plate</span> Circulation is Confined to Upper Mantle</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Plumes from deep mantle are widely conjectured to define an absolute reference frame, inaugurate rifting, drive <span class="hlt">plates</span>, and profoundly modify oceans and continents. Mantle properties and composition are assumed to be whatever enables plumes. Nevertheless, purported critical evidence for plume speculation is false, and all data are better interpreted without plumes. Plume fantasies are made ever more complex and ad hoc to evade contradictory data, and have no predictive value because plumes do not exist. All plume conjecture derives from Hawaii and the guess that the Emperor-Hawaii inflection records a 60-degree change in Pacific <span class="hlt">plate</span> direction at 45 Ma. Paleomagnetic latitudes and smooth Pacific spreading patterns disprove any such change. Rationales for other fixed plumes collapse when tested, and hypotheses of jumping, splitting, and gyrating plumes are specious. Thermal and physical properties of Hawaiian lithosphere falsify plume predictions. Purported tomographic support elsewhere represents artifacts and misleading presentations. Asthenosphere is everywhere near solidus temperature, so melt needs a tensional setting for egress but not local heat. Gradational and inconsistent contrasts between MORB and OIB are as required by depth-varying melt generation and behavior in contrasted settings and do not indicate systematically unlike sources. MORB melts rise, with minimal reaction, through hot asthenosphere, whereas OIB melts react with cool lithosphere, and lose mass, by crystallizing refractories and retaining and assimilating fusibles. The unfractionated lower mantle of plume conjecture is contrary to cosmologic and thermodynamic data, for mantle below 660 km is more refractory than that above. Subduction, due to density inversion by top-down cooling that forms oceanic lithosphere, drives <span class="hlt">plate</span> tectonics and upper-mantle circulation. It organizes <span class="hlt">plate</span> motions and lithosphere stress, which controls <span class="hlt">plate</span> boundaries and volcanic chains. Hinge rollback is the key to kinematics. Arcs advance and collide, fast-spreading Pacific shrinks, etc. A fore-arc basin atop an <span class="hlt">overriding</span> <span class="hlt">plate</span> shows that hinge and non-shortening <span class="hlt">plate</span> front there track together: velocities of rollback and advance are equal. Convergence velocity commonly also equals rollback velocity but often is greater. Slabs sinking broadside push upper mantle back under incoming <span class="hlt">plates</span> and force rapid Pacific spreading, whereas <span class="hlt">overriding</span> <span class="hlt">plates</span> flow forward with retreating hinges. Backarc basins open behind island arcs migrating with hinges. Slabs settle on uncrossable 660-km discontinuity. (Contrary tomographic claims reflect sampling and smearing artifacts, notably due to along-slab raypaths.) <span class="hlt">Plates</span> advance over sunken slabs and mantle displaced rearward by them, and ridges spread where advancing <span class="hlt">plates</span> pull away. Ridges migrate over asthenosphere, producing geophysical and bathymetric asymmetry, and tap fresh asthenosphere into which slab material is recycled upward. Sluggish deep-mantle circulation is decoupled from rapid upper-mantle circulation, so <span class="hlt">plate</span> motions can be referenced to semistable lower mantle. Global <span class="hlt">plate</span> motions make kinematic sense if Antarctica, almost ringed by departing ridges and varying little in Cenozoic paleomagnetic position, is stationary: hinges roll back, ridges migrate, and directions and velocities of <span class="hlt">plate</span> rotations accord with subduction, including sliding and crowding of oceanic lithosphere toward free edges, as the dominant drive. (The invalid hotspot and no-net-rotation frames minimize motions of hinges and ridges, and their <span class="hlt">plate</span> motions lack kinematic sense.) Northern Eurasia also is almost stationary, Africa rotates very slowly counterclockwise toward Aegean and Zagros, Pacific <span class="hlt">plate</span> races toward surface-exit subduction systems, etc.</p> <div class="credits"> <p class="dwt_author">Hamilton, W. B.</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">390</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/12037564"> <span id="translatedtitle">An inverted <span class="hlt">continental</span> Moho and serpentinization of the forearc mantle.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Volatiles that are transported by subducting lithospheric <span class="hlt">plates</span> to depths greater than 100 km are thought to induce partial melting in the overlying mantle wedge, resulting in arc magmatism and the addition of significant quantities of material to the overlying lithosphere. Asthenospheric flow and upwelling within the wedge produce increased lithospheric temperatures in this back-arc region, but the forearc mantle (in the corner of the wedge) is thought to be significantly cooler. Here we explore the structure of the mantle wedge in the southern Cascadia subduction zone using scattered teleseismic waves recorded on a dense portable array of broadband seismometers. We find very low shear-wave velocities in the cold forearc mantle indicated by the exceptional occurrence of an 'inverted' <span class="hlt">continental</span> Moho, which reverts to normal polarity seaward of the Cascade arc. This observation provides compelling evidence for a highly hydrated and serpentinized forearc region, consistent with thermal and petrological models of the forearc mantle wedge. This serpentinized material is thought to have low strength and may therefore control the down-dip rupture limit of great thrust earthquakes, as well as the nature of large-scale flow in the mantle wedge. PMID:12037564</p> <div class="credits"> <p class="dwt_author">Bostock, M G; Hyndman, R D; Rondenay, S; Peacock, S M</p> <p class="dwt_publisher"></p> <p class="publishDate">2002-05-30</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">391</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/14534583"> <span id="translatedtitle">Growth of early <span class="hlt">continental</span> crust by partial melting of eclogite.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">The tectonic setting in which the first <span class="hlt">continental</span> crust formed, and the extent to which modern processes of arc magmatism at convergent <span class="hlt">plate</span> margins were operative on the early Earth, are matters of debate. Geochemical studies have shown that felsic rocks in both Archaean high-grade metamorphic ('grey gneiss') and low-grade granite-greenstone terranes are comprised dominantly of sodium-rich granitoids of the tonalite-trondhjemite-granodiorite (TTG) suite of rocks. Here we present direct experimental evidence showing that partial melting of hydrous basalt in the eclogite facies produces granitoid liquids with major- and trace-element compositions equivalent to Archaean TTG, including the low Nb/Ta and high Zr/Sm ratios of 'average' Archaean TTG, but from a source with initially subchondritic Nb/Ta. In modern environments, basalts with low Nb/Ta form by partial melting of subduction-modified depleted mantle, notably in intraoceanic arc settings in the forearc and back-arc regimes. These observations suggest that TTG magmatism may have taken place beneath granite-greenstone complexes developing along Archaean intraoceanic island arcs by imbricate thrust-stacking and tectonic accretion of a diversity of subduction-related terranes. Partial melting accompanying dehydration of these generally basaltic source materials at the base of thickened, 'arc-like' crust would produce compositionally appropriate TTG granitoids in equilibrium with eclogite residues. PMID:14534583</p> <div class="credits"> <p class="dwt_author">Rapp, Robert P; Shimizu, Nobumichi; Norman, Marc D</p> <p class="dwt_publisher"></p> <p class="publishDate">2003-10-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">392</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFMGP34A..02B"> <span id="translatedtitle">An Amphibious Magnetotelluric Study at the South Chilean <span class="hlt">Continental</span> Margin</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">A large network of long-period magnetotelluric sites was operated in the southern Chilean Andes between latitudes 37.5--41°S. It consists of 3 profiles from the coast of the Pacific Ocean to the volcanic arc, several connecting sites and more detailed investigations around active Villarrica and Llaima volcanoes. In 2004/2005 one profile was extended with sea-bottom stations across the trench towards the Pacific <span class="hlt">plate</span> as part of the multi-disciplinary TIPTEQ programme. While analysis of offshore data is still ongoing, the onshore data display an unexpected first-order effect: without exception real induction vectors at all sites point consistently NE for long periods over the whole study area, overprinting any other effect which might be connected to conductivity anomalies along the N10°E striking <span class="hlt">continental</span> margin. While 3-D models with realistic geometries cannot account for this highly anomalous behavior of tippers, quite simple 2-D models incorporating anisotropy explain the data at least qualitatively. The ocean (modeled with crude bathymetry) accounts for the large tipper magnitudes, while an anisotropic layer in the upper-middle crust is responsible for the deflection of vectors. The direction of the highly conductive axis is NW-SE, in good agreement with the multitude of fault systems observed at the surface in the forearc and arc regions. The South Chilean crust has thus to be considered as deeply fractured with far-reaching consequences for migration of fluids and melts, where appropriate conditions exist.</p> <div class="credits"> <p class="dwt_author">Brasse, H.; Kapinos, G.; Li, Y.; Chave, A.</p> <p class="dwt_publisher"></p> <p class="publishDate">2005-12-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">393</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T31E..08M"> <span id="translatedtitle">Blocks or Continuous Deformation in Large-Scale <span class="hlt">Continental</span> Geodynamics: Ptolemy Versus Copernicus, Kepler, and Newton (Invited)</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">The enhanced precision and resolution of GPS velocity fields within active <span class="hlt">continental</span> regions have highlighted two views of how best to describe these fields: (1) as relative movements of effectively rigid (or elastic) blocks, essentially <span class="hlt">plate</span> tectonics with many <span class="hlt">plates</span>, or (2) as continuous deformation of a (non-Newtonian) viscous fluid in a gravity field. The operative question is not: Are there blocks? Of course, there are. It is: Do blocks help us understand the deformation? Dan McKenzie used to say, 40 years ago, that the reason <span class="hlt">plate</span> tectonics was accepted so easily was that the kinematics of <span class="hlt">plate</span> motion could be analyzed separately from the dynamics that underlies that motion. No such separation seems to work for <span class="hlt">continental</span> tectonics, where crust thickens or thins, and where the dynamics, both stresses and the gravitational body force, and kinematics are intimately connected via a constitutive relation that links strain rate to stress. Treating <span class="hlt">continental</span> deformation in terms of blocks is like treating planetary orbits in terms of Ptolemaic epicycles; such a treatment provides an accurate description of the kinematics, but obscures dynamics. (Sea captains in the 15th Century would have been wise to use Ptolemy’s epicycles, not yet a Copernican system, to navigate their ships). A description in terms of blocks, however, seems unlikely to reveal insights into the dynamic processes and the viscosity structure of the deforming lithosphere. In Tibet, most hypothesized blocks are cut by obvious faults and must deform, if GPS measurements are not yet accurate enough to resolve such deformation. Presumably as the number of GPS control points and the precision of their velocities increase, so will numbers of blocks needed to describe the velocity field, with numbers of GPS points and numbers of blocks obeying a fractal relationship. The important unanswered question concerns how best to describe the constitutive equation for <span class="hlt">continental</span> lithosphere? The Tibetan Plateau illustrates this failing of <span class="hlt">plate</span> tectonics (or crustal blocks) especially well. In particular, because of the large lateral variations in gravitational potential energy, it offers the best region in which to study dynamics of <span class="hlt">continental</span> deformation.</p> <div class="credits"> <p class="dwt_author">Molnar, P. H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2010-12-01</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">394</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://adsabs.harvard.edu/abs/2004JPhD...37.2607S"> <span id="translatedtitle">Pixelated neutron image <span class="hlt">plates</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p class="result-summary">Neutron image <span class="hlt">plates</span> (NIPs) have found widespread application as neutron detectors for single-crystal and powder diffraction, small-angle scattering and tomography. After neutron exposure, the image <span class="hlt">plate</span> can be read out by scanning with a laser. Commercially available NIPs consist of a powder mixture of BaFBr : Eu2+ and Gd2O3 dispersed in a polymer matrix and supported by a flexible polymer sheet. Since BaFBr : Eu2+ is an excellent x-ray storage phosphor, these NIPs are particularly sensitive to ggr-radiation, which is always present as a background radiation in neutron experiments. In this work we present results on NIPs consisting of KCl : Eu2+ and LiF that were fabricated into ceramic image <span class="hlt">plates</span> in which the alkali halides act as a self-supporting matrix without the necessity for using a polymeric binder. An advantage of this type of NIP is the significantly reduced ggr-sensitivity. However, the much lower neutron absorption cross section of LiF compared with Gd2O3 demands a thicker image <span class="hlt">plate</span> for obtaining comparable neutron absorption. The greater thickness of the NIP inevitably leads to a loss in spatial resolution of the image <span class="hlt">plate</span>. However, this reduction in resolution can be restricted by a novel image <span class="hlt">plate</span> concept in which a ceramic structure with square cells (referred to as a 'honeycomb') is embedded in the NIP, resulting in a pixelated image <span class="hlt">plate</span>. In such a NIP the read-out light is confined to the particular illuminated pixel, decoupling the spatial resolution from the optical properties of the image <span class="hlt">plate</span> material and morphology. In this work, a comparison of experimentally determined and simulated spatial resolutions of pixelated and unstructured image <span class="hlt">plates</span> for a fixed read-out laser intensity is presented, as well as simulations of the properties of these NIPs at higher laser powers.</p> <div class="credits"> <p class="dwt_author">Schlapp, M.; Conrad, H.; von Seggern, H.</p> <p class="dwt_publisher"></p> <p class="publishDate">2004-09-01</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">395</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/intro/activities/29360.html"> <span id="translatedtitle"><span class="hlt">Plate</span> Tectonics Jigsaw</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p class="result-summary">This activity is a slight variation on an original activity, Discovering <span class="hlt">Plate</span> Boundaries, developed by Dale Sawyer at Rice University. I made different maps, including more detail in all of the datasets, and used a different map projection, but otherwise the general progression of the activity is the same. More information about jigsaw activities in general can be found in the Jigsaws module. The activity occurs in several sections, which can be completed in one or multiple classes. In the first section, students are divided into "specialist" groups, and each group is given a global map with a single dataset: global seismicity, volcanoes, topography, age of the seafloor, and free-air gravity. Each student is also given a map of <span class="hlt">plate</span> boundaries. Their task in the specialist group is to become familiar with their dataset and develop categories of <span class="hlt">plate</span> boundaries based only on their dataset. Each group then presents their results to the class. In the second section, students reorganize into groups with 1-2 of each type of specialist per group. Each new group is given a <span class="hlt">plate</span>, and they combine their different datasets on that one <span class="hlt">plate</span> and look for patterns. Again, each <span class="hlt">plate</span> group presents to the class. The common patterns and connections between the different datasets quickly become apparent, and the final section of the activity involves a short lecture from the instructor about types of <span class="hlt">plate</span> boundaries and why the common features are generated at those <span class="hlt">plate</span> boundaries. A follow-up section or class involves using a problem-solving approach to explain the areas that don't "fit" into the typical boundary types - intra-<span class="hlt">plate</span> volcanism, earthquakes in the Eastern California Shear Zone, etc.</p> <div class="credits"> <p class="dwt_author">Egger, Anne</p> <p class="dwt_publisher"></p> <p class="publishDate"></p> </div> </div> </div> </div> <div class="floatContainer result " lang="en"> <div class="resultNumber element">396</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17794568"> <span id="translatedtitle">A budget for <span class="hlt">continental</span> growth and denudation.</span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p class="result-summary">Oceanic crustal material on a global scale is re-created every 110 million years. From the data presented it is inferred that potential sialic material is formed at a rate of about 1.35 cubic kilometers per year, including hemipelagic volcanic sediments that accumulate at a rate of about 0.05 cubic kilometer per year. It is estimated that the influx of 1.65 cubic kilometers per year of terrigenous and biogenic sediment is deposited on the deep ocean, and this represents <span class="hlt">continental</span> denudation. Because all this material is brought into a subduction zone, <span class="hlt">continental</span> accretion rates, which could include all this material, may be as high as 3.0 cubic kilometers per year with a potential net growth for continents of 1.35 cubic kilometers per year. PMID:17794568</p> <div class="credits"> <p class="dwt_author">Howell, D G; Murray, R W</p> <p class="dwt_publisher"></p> <p class="publishDate">1986-07-25</p> </div> </div> </div> </div> <div class="floatContainer result odd" lang="en"> <div class="resultNumber element">397</div> <div class="resultBody element"> <p class="result-title"><a target="resultTitleLink" href="http://science.gov/scigov/link.html?type=RESULT&redirectUrl=http://www.osti.gov/scitech/biblio/5787852"> <span id="translatedtitle">High loading uranium <span class="hlt">plate</span></span></a>  </p> <div class="result-meta"> <p class="source"><a target="_blank" id="logoLink" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p class="result-summary">Two embodiments of a high uranium fuel <span class="hlt">plate</span> are disclosed which contain a meat comprising structured uranium compound confined between a pari of diffusion bonded ductile metal cladding <span class="hlt">plates</span> uniformly covering the meat, the meat hiving a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel <span class="hlt">plates</span> are fabricated by a hot isostatic pressing process.</p> <div class="credits"> <p class="dwt_author">Wiencek, T.C.; Domagala, R.F.; Thresh, H.R.</p> <p class="dwt_publisher"></p> <p class="publishDate">1990-10-16</p> </div> </div> </div> </div> <div class="floatContainer result " lang="en">