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Sample records for active mountain belt

  1. Chemical weathering in active mountain belts controlled by stochastic bedrock landsliding

    NASA Astrophysics Data System (ADS)

    Emberson, Robert; Hovius, Niels; Galy, Albert; Marc, Odin

    2016-01-01

    A link between chemical weathering and physical erosion exists at the catchment scale over a wide range of erosion rates. However, in mountain environments, where erosion rates are highest, weathering may be kinetically limited and therefore decoupled from erosion. In active mountain belts, erosion is driven by bedrock landsliding at rates that depend strongly on the occurrence of extreme rainfall or seismicity. Although landslides affect only a small proportion of the landscape, bedrock landsliding can promote the collection and slow percolation of surface runoff in highly fragmented rock debris and create favourable conditions for weathering. Here we show from analysis of surface water chemistry in the Southern Alps of New Zealand that weathering in bedrock landslides controls the variability in solute load of these mountain rivers. We find that systematic patterns in surface water chemistry are strongly associated with landslide occurrence at scales from a single hillslope to an entire mountain belt, and that landslides boost weathering rates and river solute loads over decades. We conclude that landslides couple erosion and weathering in fast-eroding uplands and, thus, mountain weathering is a stochastic process that is sensitive to climatic and tectonic controls on mass wasting processes.

  2. The Jura Mountains — an active foreland fold-and-thrust belt?

    NASA Astrophysics Data System (ADS)

    Becker, Arnfried

    2000-06-01

    Recently completed in situ stress measurements using the borehole slotter at 33 new test sites within the Swiss and French Jura Mountains, combined with previously published stress data, allow a detailed description of the contemporary state of stress in this fold-and-thrust belt and the adjacent foreland. Five stress provinces can be recognized, with two different general orientations of maximum horizontal stress SH: (1) the Central and Southwest Provinces with a NNW-SSE to NNE-SSW orientation; (2) the East, Northwest and Southeast Provinces with an E-W to NW-SE orientation. Stress magnitudes are in general higher in the southern than in the northern Jura Mountains. Characteristic of the northern Jura is an E-W-trending zone of low stress magnitudes which can be traced from the Bresse Depression south of Besançon to the eastern end of the Jura northwest of Zurich. Boundaries of stress provinces show poor agreement with boundaries of tectonic units in the Jura. In addition, stress provinces extend beyond the boundaries of the Jura Mountains into their foreland. Furthermore, palaeo-stress orientations show large discrepancies with respect to the contemporary stress orientation. These findings are considered to indicate a termination of Jura thin-skinned foreland tectonics, which probably took place some time between 9 and 4 Ma according to palaeontological and tectonic evidence. It is suggested that a new style of tectonics has commenced in the Jura Mountains, deforming both the basement directly below the Jura fold-and-thrust belt and the cover rocks in a similar mode.

  3. Relict landscapes in active mountain belts: their age, interpretation and geodynamic significance

    NASA Astrophysics Data System (ADS)

    van der Beek, Peter

    2010-05-01

    Planar topographic markers have been widely used to infer the topographic and erosional history of mountain belts. During the last two decades, attention has focused on high-elevation low-relief surfaces in orogenic belts, the interpretation of which has generated considerable controversy regarding their age, mechanism of formation and tectonic or climatic significance. I will review three case studies to illustrate these issues. In the Pyrenees, high-elevation, low-relief surfaces have been mapped throughout the mountain belt and were suggested to have developed at high elevations due to significant base-level rise as a result of backfilling of the southern foreland basin, which developed under endorheic conditions between Late Eocene and Late Miocene times. Isolation of these surface remnants has been suggested to result from a more erosive climate since the Pliocene. However, an alternative study suggests that such relict landscape elements are restricted to the Eastern Pyrenees, developed at low elevations during the Miocene and were subsequently tectonically uplifted. This second hypothesis appears to be comforted by a suite of thermochronological, stratigraphic and geophysical data from the Eastern Pyrenees. We have used a thermo-kinematic model integrating the existing thermochronometry data from the central Pyrenees to constrain the amount and timing of base-level change in that area and find that, while significant filling and re-excavation of the southern flank must have occurred, the timing of exhumation is Late Miocene rather than Pliocene-Quaternary and the relationship with hypothetical relict landscape elements in the high chain remains unclear. In the western European Alps, widespread high-elevation low-relief surfaces develop close to the interface between crystalline basement and sedimentary cover in the "external crystalline massifs" (e.g., Pelvoux-Ecrins, Belledonne, Aar). These surfaces clearly appear to be lithologically controlled and to have

  4. Rock glaciers and the sediment dynamics in arid mountain belts

    NASA Astrophysics Data System (ADS)

    Blöthe, Jan Henrik; Höser, Thorsten; Rosenwinkel, Swenja; Korup, Oliver

    2016-04-01

    Rock glaciers are common periglacial features in highest elevations of semiarid to arid mountain ranges. Rock glaciers predominate in realms where precipitation values fall below thresholds that allow for ice glacier formation, then even outranging ice glaciers in size and number. The influence of ice glaciers on high-mountain's sediment dynamics is manifold: ice-glacier-driven erosion produces large amounts of clastic material; ice glaciers act as a conveyor belt for sediments, delivering material from their source regions to their terminus; ice glaciers entering trunk valleys form efficient dams that interrupt sediment delivery. While these mechanisms have been addressed in numerous earlier studies, the role of rock glaciers for the sediment dynamics of arid mountain belts remains elusive. We address this shortcoming by analysing a rock glacier inventory that we compiled for the Himalaya-Karakoram ranges and the Tien Shan ranges in Central Asia. Our inventory comprises more than 1000 specimen, a large number of which form dams of large trunk rivers and minor tributaries, disconnecting the sediment fluxes from upstream. In certain regions that are nearly devoid of ice-glaciers, like the Gamugah surface of NW Pakistan, rock glaciers of >10^4-m length occupy valley bottoms entirely, constituting the only mode of transport for sediments produced in headwaters. In conclusion, we call for a better understanding of the role that rock glaciers take in the sediment dynamics of arid mountain belts.

  5. Economic geology of the Copper Mountain Supracrustal Belt, Owl Creek Mountains, Fremont County, Wyoming

    SciTech Connect

    Hausel, W.D.; Graff, P.J.; Albert, K.G.

    1985-01-01

    The Archean stratigraphy and associated mineral deposits at Copper Mountain were investigated to determine if this supracrustal belt has potential commercial mineral deposits. It was concluded Copper Mountain lacks the stratigraphic and structural character of a classical greenstone belt, exhibits higher metamorphic grade, and may be better classified as a high-grade terrain. However, potential is noted for stratiform Au associated with iron formation, stratiform W associated with gneiss, and Cu-Au mineralization in strike veins. 63 refs., 9 figs., 3 tabs. (ACR)

  6. Unravelling genetics at the top: mountain islands or isolated belts?

    PubMed Central

    García-Fernández, Alfredo; Segarra-Moragues, Jose Gabriel; Widmer, Alex; Escudero, Adrian; Iriondo, José María

    2012-01-01

    Background and Aims In mountain plant populations, local adaptation has been described as one of the main responses to climate warming, allowing plants to persist under stressful conditions. This is especially the case for marginal populations at their lowest elevation, as they are highly vulnerable. Adequate levels of genetic diversity are required for selection to take place, while high levels of altitudinal gene flow are seen as a major limiting factor potentially precluding local adaptation processes. Thus, a compromise between genetic diversity and gene flow seems necessary to guarantee persistence under oncoming conditions. It is therefore critical to determine if gene flow occurs preferentially between mountains at similar altitudinal belts, promoting local adaptation at the lowest populations, or conversely along altitude within each mountain. Methods Microsatellite markers were used to unravel genetic diversity and population structure, inbreeding and gene flow of populations at two nearby altitudinal gradients of Silene ciliata, a Mediterranean high-mountain cushion plant. Key Results Genetic diversity and inbreeding coefficients were similar in all populations. Substantial gene flow was found both along altitudinal gradients and horizontally within each elevation belt, although greater values were obtained along altitudinal gradients. Gene flow may be responsible for the homogeneous levels of genetic diversity found among populations. Bayesian cluster analyses also suggested that shifts along altitudinal gradients are the most plausible scenario. Conclusions Past population shifts associated with glaciations and interglacial periods in temperate mountains may partially explain current distributions of genetic diversity and population structure. In spite of the predominance of gene flow along the altitudinal gradients, local genetic differentiation of one of the lower populations together with the detection of one outlier locus might support the existence

  7. Creating and destroying mountain belts in a sandbox (Invited)

    NASA Astrophysics Data System (ADS)

    Hernandez, M.

    2009-12-01

    M. Hernandez-1, L. Cruz-1, G. Hilley-1, J. Malinski-1, W.A. Take-2 1-Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 2-Department of Civil Engineering, Queen's University, Kingston, Canada This study uses a new experimental approach to model the kinematic response of the Aconcagua fold-and-thrust belt to erosion using a deforming sand wedge that is eroded according to a fluvial bedrock incision rule. Our objective is to thoroughly examine the impact that erosion may have had on the kinematics of this fold-and-thrust belt and test the applicability of our approach. Our experimental apparatus allows for a variety of boundary conditions to be applied to the wedge, including constant displacement rate, time-varying displacement rate, constant loading, and time-varying loading. This setting also includes three digital cameras that are connected to the apparatus to monitor the top and one side of the experimental sandbox. In this new experimental approach, as we deform the sand wedge, or mountain belt, we select specific time intervals to calculate, using a Matlab code, the topographic slope derived from our erosion rule. We then use a linear laser to project the calculated topographic slope into the sand wedge and remove any excess of sand with a vacuum cleaner. We then let the wedge continue to deform and repeat the above process. After the end of each experiment, we use Particle Image Velocimetry (PIV) techniques to analyze the movement of the sand particles throughout the experiment. The use of PIV requires the images from all three cameras to be corrected due to lens distortion. We use available software, such as Photoshop, to correct and crop the images. The results of our constant-displacement rate experiments indicate, based on geometric comparisons against natural topographic measurements, that our erosional rule could be satisfactorily applied to sandbox simulations. Each of the main deformational stages identified in the

  8. Arsenic in groundwaters in the Northern Appalachian Mountain belt: A review of patterns and processes

    NASA Astrophysics Data System (ADS)

    Peters, Stephen C.

    2008-07-01

    Naturally occurring arsenic in the bedrock of the Northern Appalachian Mountain belt was first recognized in the late 19th century. The knowledge of the behavior of arsenic in groundwater in this region has lagged behind nearly a century, with the popular press reporting on local studies in the early 1980s, and most peer-reviewed research articles on regional patterns conducted and written in the late 1990s and early 2000s. Research reports have shown that within this high arsenic region, between 6% and 22% of households using private drinking water wells contain arsenic in excess of 10 µg/L, the United States Environmental Protection Agency's maximum contaminant level. In nearly all reports, arsenic in drinking water was derived from naturally occurring geologic sources, typically arsenopyrite, substituted sulfides such as arsenian pyrite, and nanoscale minerals such as westerveldite. In most studies, arsenic concentrations in groundwater were controlled by pH dependent adsorption to mineral surfaces, most commonly iron oxide minerals. In some cases, reductive dissolution of iron minerals has been shown to increase arsenic concentrations in groundwater, more commonly associated with anthropogenic activities such as landfills. Evidence of nitrate reduction promoting the presence of arsenic(V) and iron(III) minerals in anoxic environments has been shown to occur in surface waters, and in this manuscript we show this process perhaps applies to groundwater. The geologic explanation for the high arsenic region in the Northern Appalachian Mountain belt is most likely the crustal recycling of arsenic as an incompatible element during tectonic activity. Accretion of multiple terranes, in particular Avalonia and the Central Maine Terrane of New England appear to be connected to the presence of high concentrations of arsenic. Continued tectonic activity and recycling of these older terranes may also be responsible for the high arsenic observed in the Triassic rift basins

  9. A Major Out of Sequence Fault in Central Range and Its Implication to Mountain Building Process of Taiwan Orogenic Belt

    NASA Astrophysics Data System (ADS)

    Lee, Y. H.

    2015-12-01

    A Major Out of Sequence Fault in Central Range and Its Implication to Mountain Building Process of Taiwan Orogenic Belt Yuan-Hsi Lee1, Wei Lo2, Wei-Hau Wang1, Tim-Byrne 3, Ruey-Juen Rau 41. Department of Earth and Environmental Sciences, National Chung Cheng University, Taiwan, R.O.C. 2. Department of Materials and Mineral Resources Engineering, Taipei, National Taipei University of Technology, Taiwan, R.O.C. 3. Center for Integrative Geosciences, University of Connecticut, Storrs, CT, USA 4. Department of Earth Science, National Chen-Kung University, Taiwan, R.O.C. Taiwan mountain belt results from collision between Eurasia continental crust and Philippine Sea plate that result in exposing the metamorphic complex with high exhumation rate in eastern Central Range of Taiwan orogenic belt. In this study we combine with field survey, zircon fission track (ZFT), metamorphic grade, and tomography data to identify there exists a major out of sequence fault (MOSF) in eastern Central Range of Taiwan orogenic belt. This MOSF extends from north to south of eastern central Range with several segments and the total length is more than 250 km. The ZFT shows total annealing age of ca.1-3 Ma on the hanging wall and partial annealing ages on the foot wall. The seismicity data indicates the MOSF is still active from central to southern central Range. We consider that the MOSF is related with crustal channel flow in depth. To the western side of crustal flow it shows thrusting mechanism associated with MOSF and the normal faults (or normal shearing zone) develop in eastern side of the crustal channel flow. This crustal channel flow is also related with exposing the metamorphic complex in Central Range that is important mechanism for the mountain building process of Taiwan orogenic belt.

  10. Structural controls on Tertiary orogenic gold mineralization during initiation of a mountain belt, New Zealand

    NASA Astrophysics Data System (ADS)

    Craw, D.; Begbie, M.; MacKenzie, D.

    2006-10-01

    Two types of structurally controlled hydrothermal mineralization have occurred during folding of fissile schist in southern New Zealand: fold-related mineralization and normal fault-related mineralization. Both types have the same mineralogy and textures, and are dominated by quartz-ankerite veins and silicified breccias with ankeritic alteration. Most mineralized zones are thin (centimetre scale), although host schist is commonly impregnated with ankerite up to 20 m away. Thick (up to 5 m wide) mineralized zones are generally gold-bearing and contain pyrite and arsenopyrite with stibnite pods locally. Some of these auriferous zones have been extensively mined historically despite rugged topography and difficult access. Mineralization occurred during regional tectonic compression in the initial stages of development of the Southern Alps mountain belt at the Pacific-Australian plate boundary in the Miocene. Most of the gold-bearing deposits occur in east to south-east, striking normal faults that cut across mesoscopic folds in a belt that coincides with the southern termination of a regional-scale north trending antiform. Mineralized zones have similar structural control and relative timing to a nearby swarm of Miocene lamprophyre dykes and carbonatites. Limited stable isotopic data (C and O) and trace element geochemistry suggest that there was probably no genetic link between the igneous activity and gold mineralization. However, these two types of fluid flow have been controlled by the same tectonically created crustal plumbing system. This Miocene hydrothermal activity and gold deposition demonstrates that orogenic (mesothermal) mineralization can occur during the inception of an orogenic belt, not just in the latter stages as is commonly believed. These Miocene structures have been preserved in the orogen because the locus of uplift has moved northwards, so the early-formed gold deposits have not yet been structurally overprinted or eroded.

  11. Geological respiration of a mountain belt revealed by the trace element rhenium

    NASA Astrophysics Data System (ADS)

    Hilton, Robert G.; Gaillardet, Jérôme; Calmels, Damien; Birck, Jean-Louis

    2014-10-01

    Oxidation of rock-derived, petrogenic, organic carbon (OCpetro) during weathering of sedimentary rocks is a major source of carbon dioxide (CO2) to the atmosphere. This geological respiration is thought to be enhanced by physical erosion, suggesting that mountain belts could release large amounts of CO2 to counter the CO2 sequestration achieved by the erosion, riverine transfer and oceanic burial of organic carbon from the terrestrial biosphere. However, OCpetro oxidation rates in mountain belts have not been quantified. Here we use rhenium (Re) as a proxy to track OCpetro oxidation in mountain river catchments of Taiwan, where existing measurements of physical erosion rate allow the controls on OCpetro oxidation to be assessed. Re has been shown to be closely associated with OCpetro in rocks and following oxidation during chemical weathering forms a soluble oxyanion (ReO4-) which contributes to the dissolved load of rivers. Soils on meta-sedimentary rocks in Taiwan show that Re loss is coupled to OCpetro loss during weathering, confirming previous observations from soil profiles on sedimentary rocks elsewhere. In Taiwan rivers, dissolved Re flux increases with the catchment-average sediment yield, suggesting that physical erosion rate is a major control on OCpetro oxidation. Based on our current understanding of Re mobility during weathering, the dissolved Re flux can be used to quantify an upper bound on the OCpetro oxidation rate and the associated CO2 transfer. The estimated CO2 release from this mountain belt by OCpetro oxidation does not negate estimates of CO2 sequestration by burial of biospheric OC offshore. The findings are compared to OC transfers estimated for the Himalaya, where OCpetro oxidation in the mountain belt remains unconstrained. Together, these cases suggest that mountain building in the tropics can result in a net sink of OC which sequesters atmospheric CO2.

  12. Research on an Active Seat Belt System

    NASA Astrophysics Data System (ADS)

    Kawashima, Takeshi

    In a car crash, permanent injury can be avoided if deformation of an occupant's rib cage is maintained within the allowable value. In order to realize this condition, the occupant's seat belt tension must be instantaneously adjusted by a feedback control system. In this study, a seat belt tension control system based on the active shock control system is proposed. The semi-active control law used is derived from the sliding mode control method. One advantage of this proposed system is that it does not require a large power actuator because the seat belt tension is controlled by a brake mechanism. The effectiveness is confirmed by numerical simulation using general parameters of a human thorax and a passenger car in a collision scenario with a wall at a velocity of 100 km/h. The feasibility is then confirmed with a control experiment using a scale model of about 1/10 scale. The relative displacement of the thorax model approaches the allowable value smoothly along the control reference and settles near this value. Thus, the proposed seat belt tension control system design is established.

  13. First-order control of syntectonic sedimentation on crustal-scale structure of mountain belts

    NASA Astrophysics Data System (ADS)

    Erdős, Zoltán.; Huismans, Ritske S.; Beek, Peter

    2015-07-01

    The first-order characteristics of collisional mountain belts and the potential feedback with surface processes are predicted by critical taper theory. While the feedback between erosion and mountain belt structure has been fairly extensively studied, less attention has been given to the potential role of synorogenic deposition. For thin-skinned fold-and-thrust belts, recent studies indicate a strong control of syntectonic deposition on structure, as sedimentation tends to stabilize the thin-skinned wedge. However, the factors controlling basement deformation below fold-and-thrust belts, as evident, for example, in the Zagros Mountains or in the Swiss Alps, remain largely unknown. Previous work has suggested that such variations in orogenic structure may be explained by the thermotectonic "age" of the deforming lithosphere and hence its rheology. Here we demonstrate that sediment loading of the foreland basin area provides an additional control and may explain the variable basement involvement in orogenic belts. When examining the role of sedimentation, we identify two end-members: (1) sediment-starved orogenic systems with thick-skinned basement deformation in an axial orogenic core and thin-skinned deformation in the bordering forelands and (2) sediment-loaded orogens with thick packages of synorogenic deposits, derived from the axial basement zone, deposited on the surrounding foreland fold-and-thrust belts, and characterized by basement deformation below the foreland. Using high-resolution thermomechanical models, we demonstrate a strong feedback between deposition and crustal-scale thick-skinned deformation. Our results show that the loading effects of syntectonic sediments lead to long crustal-scale thrust sheets beneath the orogenic foreland and explain the contrasting characteristics of sediment-starved and sediment-loaded orogens, showing for the first time how both thin- and thick-skinned crustal deformations are linked to sediment deposition in these

  14. Thermal effects of overthrusting, Little Mountains thrust belt, eastern New York

    SciTech Connect

    Zadins, Z.; Mitra, G.

    1986-05-01

    Thermal models constrained by clay mineral assemblages, vitrinite reflectance, and palinspatic restoration are used to interpret the thermal history of the Appalachian thrust belt of eastern New York. The deformed Appalachian foreland of eastern New York is comprised of two adjacent north-south-trending thrust belts: (1) the Taconic Mountains, allochthons emplaced during the Late Ordovician Taconic orogeny; and (2) Little Mountains thrust belt, faulted and folded Lower Devonian carbonates exhibiting well-developed solution cleavage, deformed during the Devonian Acadian or Pennsylvanian Alleghenian orogeny. Conodont alteration index from the Little Mountains range from 4.0 to 4.5, suggesting temperatures of 190/sup 0/-240/sup 0/C. This thermal imprint may be attributed to burial heating from 8 km of post-Lower Devonian molasse in the Catskill Mountains, whose present thickness is 2.3 km. Elevated temperature-pressure conditions resulting from an overriding thrust sheet would facilitate formation of solution cleavage in the Little Mountains, in a manner similar to that demonstrated in the Idaho-Wyoming thrust belt. X-ray analysis of clay minerals from Catskill shales in the undeformed foreland show: (1) there is little or no discrete smectite; (2) illite predominates, with illite peaks being asymmetric toward lower 28 suggesting a minor component of random interstratified illite-smectite; and (3) illite has decreasing crystallinity with increasing burial depth. These results indicate sedimentary overburden has had little effect on illite crystallinity, as crystallinity should systematically increase with increasing temperatures (i.e., increasing depth). Catskill illites exhibiting decreasing crystallinites may reflect that they are detrital and are derived from progressive erosion of a Taconic thrust sheet, resulting in an inverted illite stratigraphy.

  15. The Rwenzori Mountains, a Palaeoproterozoic crustal shear belt crossing the Albertine rift system

    NASA Astrophysics Data System (ADS)

    Koehn, D.; Link, K.; Sachau, T.; Passchier, C. W.; Aanyu, K.; Spikings, A.; Harbinson, R.

    2015-04-01

    This contribution discusses the development of the Palaeoproterozoic Buganda-Toro belt in the Rwenzori Mountains and its influence on the western part of the East African Rift System in Uganda. The Buganda-Toro belt is composed of several thick-skinned nappes consisting of Archaean Gneisses and Palaeoproterozoic cover units that are thrusted northwards. The high Rwenzori Mountains are located in the frontal unit of this belt with retrograde greenschist facies gneisses towards the north, which are unconformably overlain by metasediments and amphibolites. Towards the south, the metasediments are overthrust by the next migmatitic gneiss unit that belongs to a crustal-scale nappe. The southwards dipping metasedimentary and volcanic sequence in the high Rwenzori Mountains shows an inverse metamorphic grade with greenschist facies conditions in the north and amphibolite facies conditions in the south. Early D1 deformation structures are overgrown by cordierite, which in turn grows into D2 deformation, representing the major northwards directed thrusting event. We argue that the inverse metamorphic gradient develops because higher grade rocks are exhumed in the footwall of a crustal-scale nappe, whereas the exhumation decreases towards the north away from the nappe leading to a decrease in metamorphic grade. The D2 deformation event is followed by a D3 E-W compression, a D4 with the development of steep shear zones with a NNE-SSW and SSE-NNW trend including the large Nyamwamba shear followed by a local D5 retrograde event and D6 brittle reverse faulting. The Palaeoproterozoic Buganda-Toro belt is relatively stiff and crosses the NNE-SSW running rift system exactly at the node where the highest peaks of the Rwenzori Mountains are situated and where the Lake George rift terminates towards the north. Orientation of brittle and ductile fabrics show some similarities indicating that the cross-cutting Buganda-Toro belt influenced rift propagation and brittle fault development

  16. Mountain building processes in intraplate, intracontinental oblique deformation belts: Lessons from the Gobi Altai, Mongolia

    NASA Astrophysics Data System (ADS)

    Cunningham, D.

    2012-04-01

    The Gobi Altai is an intraplate, intracontinental transpressional orogen in southern Mongolia that formed in the Late Cenozoic as a distant response to the Indo-Eurasia collision. The modern range formed within crust constructed by successive terrane accretion and ocean suturing events and widespread granite plutonism throughout the Palaeozoic. Modern reactivation of the Gobi Altai crust and the kinematics of Quaternary faults are fundamentally controlled by Palaeozoic basement structural trends, the location of rigid Precambrian blocks, orientation of SHmax and possible thermal weakening of the lower crust due to an extensive history of Mesozoic-Cenozoic basaltic volcanism in the region, and the presence of thermally elevated asthenosphere under the Hangay Dome to the north. Modern mountain building processes in the Gobi Altai typically involve reactivation of NW-striking basement structures in thrust mode and development of linking E-W left-lateral strike-slip faults which crosscut basement structures within an overall left-lateral transpressional regime. Restraining bends, other transpressional ridges and thrusted basement blocks are the main range type, but are discontinuously distributed and separated by internally drained basins filling with modern alluvial deposits. Unlike a contractional thrust belt, there is no orogenic foreland or hinterland, and thrusts are both NE and SW directed with no evidence for a basal decollement. Normal faults related to widespread Cretaceous rifting in the region are locally thrust reactivated in the NE Gobi Altai, but elsewhere appear to be unfavourably oriented for Late Cenozoic reactivation despite widespread topographic inversion of Cretaceous basin sequences. The diffuse historical seismicity in the region coupled with a complex system of interacting faults showing evidence for Quaternary movements, suggests that faults may be dormant for long periods and then reactivate. Large earthquakes may be episodic and spatially

  17. Proterozoic to mesozoic mobile-belt geology, Pensacola Mountains, Antarctica

    NASA Astrophysics Data System (ADS)

    Schmidt, D. L.

    The Pensacola Mountains consist of four unconformable sequences of: (1) graywacke (oldest), (2) platform, (3) molasses, and (4) continental (youngest) deposits. The first sequence of Middle Proterozoic graywacke deposits (Patuxent Formation) consists of turbidite quartzbearing sandstone and slate and volcanic rocks. The second sequence consist of extensive platform deposits of Lower Cambrian archaeocyathidbearing limestone and Middle Cambrian trilobitebearing limestone (Nelson Limestone) that are overlain by shale (Wiens Formation), and silicic volcanic rocks (Gambacorta Formation) including rhyolitic ignimbrite of caldera origin. The third sequence, The pre-Devonian Neptune Group consists of of basal orogenic conglomerate and more than 1,500 m of quartz-sandstone molasse that resulted from the erosion of the early Paleozoic mountains of the Ross orogeny. The fourth sequence of continental deposits of the Beacon Supergroup consists of Devonian quartz sanstone (Dover Sandstone), Permian glacial tillite (Gale Mudstone), and Permian siltstone and shale (Pecora Formation) containing glossopterid-bearing coal beds. During Early and Middle Jurassic time, and Transantarctic continental rift extensionally split the East Antarctic craton from West Antarctica as Gondwanaland began to break up. The continental rifting was shortly followed, during Late Jurassic time, by more vigorous extension resulting from major transform faulting.

  18. Mountain building and mantle dynamics: a journey through the Tethyan belt (Stephan Mueller Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Faccenna, Claudio

    2014-05-01

    The style of mantle convection beneath large oceanic plates is rather well established. On the other hand, we still have a loose grasp of what happen beneath continental plate, especially beneath mobile and convergent margins, where we expect to have vigorous convection. Here, I present some considerations about the style and evolution of mantle convection beneath convergent/collisional zones as constrained by geological - seismological data and modelling. I will consider the Alpine-Tethyan belt as a case study, exploring the idea that the style of mountain building can be used as a proxy to reconstruct mantle dynamics. The Tertiary evolution of the Tethyan belt indeed offers a unique opportunity to discuss about mountain building and mantle dynamics, as it include region such as the Mediterranean, where collision is still in its incipient stage producing Apennines style orogen, to the Himalayan-Tibetan belt, where collisional process reaches its extreme consequence. We classified those two belts as end members of a wide range of orgen. On one side, the of "slab pull" orogen, where subduction is mainly confined to the upper mantle, and rollback trench motion lead to moderately thick crustal stacks and reduced topographic signal, such as in the Mediterranean. On the other side, the "slab suction" orogen, where whole-mantle convection cells ("conveyor belts") lead to the more extreme expressions of orogeny, such as the largely thickened crust and high plateaus of present-day Tibet. For the slab suction type, deep mantle convection produces the unique conditions to drag plates toward each other, irrespective of their nature and other boundary conditions. Based on mantle circulation modeling and tectonic reconstructions, we surmise that the forces necessary to sustain slab-suction mountain building in those orogens derive, after transient slab ponding, from the mantle drag induced upon slab penetration into the lower mantle, and from an associated surge of mantle

  19. On predicting debris flows in arid mountain belts

    NASA Astrophysics Data System (ADS)

    Stolle, Amelie; Langer, Maria; Blöthe, Jan Henrik; Korup, Oliver

    2015-03-01

    The use of topographic metrics for estimating the susceptibility to, and reconstructing the characteristics of, debris flows has a long research tradition, although largely devoted to humid mountainous terrain. The exceptional 2010 monsoonal rainstorms in the high-altitude mountain desert of Ladakh and Zanskar, NW India, were a painful reminder of how susceptible arid regions are to rainfall-triggered flash floods, landslides, and debris flows. The rainstorms of August 4-6 triggered numerous debris flows, killing 182 people, devastating 607 houses, and more than 10 bridges around Ladakh's capital of Leh. The lessons from this disaster motivated us to revisit methods of predicting (a) flow parameters such as peak discharge and maximum velocity from field and remote sensing data, and (b) the susceptibility to debris flows from catchment morphometry. We focus on quantifying uncertainties tied to these approaches. Comparison of high-resolution satellite images pre- and post-dating the 2010 rainstorm reveals the extent of damage and catastrophic channel widening. Computations based on these geomorphic markers indicate maximum flow velocities of 1.6-6.7 m s- 1 with runout of up to ~ 10 km on several alluvial fans that sustain most of the region's settlements. We estimate median peak discharges of 310-610 m3 s- 1, which are largely consistent with previous estimates. Monte Carlo-based error propagation for a single given flow-reconstruction method returns a variance in discharge similar to one derived from juxtaposing several different flow reconstruction methods. We further compare discriminant analysis, classification tree modelling, and Bayesian logistic regression to predict debris-flow susceptibility from morphometric variables of 171 catchments in the Ladakh Range. These methods distinguish between fluvial and debris flow-prone catchments at similar success rates, but Bayesian logistic regression allows quantifying uncertainties and relationships between potential

  20. Late Pleistocene to Holocene alluvial tableland formation in an intra-mountainous basin in a tectonically active mountain belt ― A case study in the Puli Basin, central Taiwan

    NASA Astrophysics Data System (ADS)

    Tseng, Chia-Han; Lüthgens, Christopher; Tsukamoto, Sumiko; Reimann, Tony; Frechen, Manfred; Böse, Margot

    2016-01-01

    The morphology in Taiwan is a product of high tectonic activity at the convergent margin and East Asian monsoon climate. Tablelands are prominent geomorphic features in the Puli Basin in central Taiwan. These tablelands provide an archive to understand links between past climatic evolution and tectonic events resulting in the formation of the present-day landforms. To establish a geochronological framework for the alluvium underlying the tablelands in the Puli Basin, optically stimulated luminescence dating was applied to obtain burial ages. The numerical data indicate an accumulation phase of alluvial fans in the Late Pleistocene to Early Holocene transition. The study area in the Taomi River catchment, an obvious longer precursor of the Taomi River, originating from west of the Yuchih Basin, transported the sediments forming the present-day southern tablelands. During the Pleistocene-Holocene transition, the climate changed to wetter and warmer conditions, so that slope processes might have changed and an increasing transport in the fluvial system was stimulated. Fluvial and fan terraces in other river catchments in Taiwan also indicate a period of increased fluvial transport and deposition. A geomorphic evolution model in the Puli Basin is reconstructed on the basis of the chronological framework and of sedimentological features. Fluvial processes controlled by climatic change and accompanied by tectonic activities have created the diverse topography in the Puli Basin.

  1. Oroclines - a century of discourse about curved mountain belts (Petrus Peregrinus Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Van der Voo, Rob

    2014-05-01

    Exactly a century ago, in early 2014, a discussion appeared in the Journal of Geology by William H. Hobbs entitled "Mechanics of formation of arcuate mountains". In it, he notes how the concept of nappes "has now overcome all opposition in Switzerland" and, presumably in other countries just as much. With horizontal transport so central to the nappe concept, this must have paved the way for the idea that emplacement of trust sheets may have involved rotations. Where such rotations form a coherent regional pattern, a curved mountain belt may be the result. While the paper by Hobbs does not mention the word orocline, and while the dynamics of the situation is not yet illuminated, one must give credit to him for his foresights. The term "orocline" was introduced by S. Warren Carey of Tasmania in 1955, as part of a kinematic analysis of rhomb- and triangle-shaped basins and curved mountain belts. When the displacements involved in the analysis are undone, as he did, for instance, in the western Mediterranean, a grand scheme of simple convergent and divergent patterns emerges. Noteworthy is, of course, the fact that this mobilistic analysis preceded plate tectonics by more than a decade. From Carey (although not exactly in his words) we have inherited the definition of orocline, as "a thrust belt or orogen that is curved in map-view due to it having been bent or buckled about a vertical axis of rotation". Because oroclinal bending involves rotations, the declinations of paleomagnetic studies can be utilized to support and quantify them, and early efforts were already made in the 1960's and early 1970's to do so (e.g., Krs in the Carpathians; Ries & Shackleton in Cantabria; Roy, Opdyke & Irving in the Central Appalachians; Packer & Stone in Alaska). Curved mountain belts everywhere were subsequently investigated, and typically shown by paleomagnetists to be of the oroclinal variety. Few curved belts turned out to be curved from the start. Because these studies were

  2. Intensity of geomorphological processes in NW sector of Pacific rim marginal mountain belts

    NASA Astrophysics Data System (ADS)

    Lebedeva, Ekaterina; Shvarev, Sergey; Gotvansky, Veniamin

    2014-05-01

    Continental marginal mountains, including the mountain belts of Russian Far East, are characterized by supreme terrain contrast, mosaic structure of surface and crust, and rich complex of modern endogenous processes - volcanism, seismicity, and vertical movements. Unstable state of geomorphological systems and activity of relief forming processes here is caused also by deep dissected topography and the type and amount of precipitation. Human activities further stimulate natural processes and increase the risk of local disasters. So these territories have high intensity (or tension) of geomorphological processes. Intensity in the authors' understanding is willingness of geomorphological system to be out of balance, risk of disaster under external and internal agent, both natural and human. Mapping with quantitative accounting of intensity of natural and human potential impact is necessary for indication the areal distribution trends of geomorphological processes intensity and zones of potential risk of disasters. Methods of map drowning up are based on several criteria analyzing: 1) total terrain-form processes and their willingness to be a hazard-like, 2) existence, peculiarity and zoning of external agents which could cause extreme character of base processes within the territory, 3) peculiarity of terrain morphology which could cause hazard way of terrain-form processes. Seismic activity is one of the most important factors causing activation of geomorphological processes and contributing to the risk of dangerous situations. Earthquake even small force can provoke many catastrophic processes: landslides, mudslides, avalanches and mudflows, tsunami and others. Seismic gravitational phenomenons of different scale accompany almost all earthquakes of intensity 7-8 points and above, and some processes, such as avalanches, activated by seismic shocks intensity about 1-3 points. In this regard, we consider it important selection of high intensity seismic zones in

  3. Structure and evolution of the crust beneath the Scandinavian mountain belt from geophysical data

    NASA Astrophysics Data System (ADS)

    England, Richard; Ben Mansour, Walid; Ebbing, Jörg; Moorkamp, Max

    2015-04-01

    Geophysical data provides an image of the deep sub-subsurface velocity, density or conductivity structure of mountain belts at the present day. However, that present day structure is the result of the evolution of the mountain belt over a period of time and hence the geophysical image represents the cumulative effects of the development of the mountain belt. The Scandinavian mountain belt has a protracted history. While it is best known from studies of the surface geology for preserving the core of the Scandinavian Caledonides, the crust forming the root of that orogen was involved in earlier Fennoscandian and Sveco-Norwegian mountain building and has subsequently been involved in epeirogenic uplift which has led to the present topographic expression. We present the results of 3 onshore geophysical profiles across the south, central and northern parts of the Scandinavian mountains approximately orthogonal to the strike of the Caledonian orogen. Acquired to look for along strike variations in crustal structure that could be related to epeirogenesis and variations in present day topography, these profiles all show very similar features. Moving from East to West: crust between 42 and 45 km thick with a very high velocity (>7.2 km/s) lower crustal layer up to 10 km thick passes into a region beneath the current mountain range of crust of similar thickness but without the high velocity layer. There is no significant orogenic root preserved which could be associated with the Scandinavian Caledonides. A minor root is present to the east of the present topographic high. There is no evidence for the thrust nappes which dominate the near surface geology having a significant geophysical expression. This picture is consistent with the core of the Scandinavian Caledonides being preserved along the Norwegian coastline (which is broadly consistent with the classic Wilson Cycle model) and the bulk of the crust beneath Norway and Sweden being dominated by basement formed by

  4. Paleomagnetic results from the Shasta Bally Plutonic Belt in the Klamath Mountains Province, northern California

    NASA Astrophysics Data System (ADS)

    Mankinen, Edward A.; Irwin, William P.; Grommé, C. Sherman

    1988-01-01

    Available paleomagnetic data show approximately 100° of clockwise rotation for Permian and Triassic strata of the Eastern Klamath terrane. Jurassic strata of this terrane are rotated approximately 60° clockwise, which is comparable to rotations reported for Jurassic plutons that occur elsewhere in the Klamath Mountains province. Paleomagnetic data obtained during the present study from the Shasta Bally belt of Cretaceous plutons indicate 25.7° ± 13.6° of clockwise rotation for the province since Early Cretaceous time (≃ 136 Ma). The waning stages of rotation at the time of emplacement of the Shasta Bally belt plutons, which was closely followed by deposition of basal strata (Lower Cretaceous) of the Great Valley sequence, probably represents completion of accretion of the province to cratonic North America.

  5. Morphotectonic analysis of the Kaftar lake basin in the High Zagros Mountain Belt, (Fars province, Iran)

    NASA Astrophysics Data System (ADS)

    Farhoudi, Gh.; Samiee Ardabili, J.

    2009-04-01

    The Kaftar lake basin is located in the High Zagros Mountain Belt in the southwest of Namdan plain in the northern part of Fars province (Iran). The studied area surrounded by Gandboi ridge with E-W trend in the north and NW-SE trended Bareaftab anticline in the south. The main faults in the studied area are Moosakhani and Korchool (Kaftar) thrust faults, which are recorded in the Iran aeromagnetic map with T-12 and T-46, respectively. These faults are on the south eastern edge of the Zagros thrust system. With this study, in which we have used automatic lineament extraction algorithm from multi sources, high resolution morphometric data, analysis of morphotectonic elements based on high spatial resolution satellite imagery and digital elevation model, and field study. We have tried to detect the tectonic activities and understand the origin and evolution of the Kaftar lake basin. Based on analysis of existing data and results of this study, Gandboi ridge is a syncline with complex topography uplifted and rotated by Korchool fault. Bareaftab anticline, which is located in the hanging wall of Moosakhani fault, is a fault propagation fold and has also been formed by this fault. Based on the bed rock map of Namdan plain,The Kaftar lake has been produced in a depression within folds caused by Korchool fault. The high tectonic and karstic activities as well as the fact that the lake is not salty, indicatig a drain of the lake, proved that the Kaftar lake is a part of a polje of the karst system of Namdan plain.

  6. Visoelastic relaxation of Venusian coronae and mountain belts: Constraints on global heat flow and tectonism

    NASA Astrophysics Data System (ADS)

    Duncan, I.; Leith, A.

    1992-12-01

    Venus differs from Earth in that water is essentially absent and its surface temperatures are about 470 K higher. The competing effects of high surface temperature and dry lithologies on the long-term history of surface topography have been studied using the finite-element method. The relaxation history of surface topographic features, such as coronae and mountain belts, is a function of thermal gradient, crustal thickness and lithology, regional stresses, and basal tractions applied to the lithosphere. In this study, we have examined the relative effects of these factors over a period of 500 Ma (presumed to be the mean age of the venusian surface).

  7. Visoelastic relaxation of Venusian coronae and mountain belts: Constraints on global heat flow and tectonism

    NASA Technical Reports Server (NTRS)

    Duncan, I.; Leith, A.

    1992-01-01

    Venus differs from Earth in that water is essentially absent and its surface temperatures are about 470 K higher. The competing effects of high surface temperature and dry lithologies on the long-term history of surface topography have been studied using the finite-element method. The relaxation history of surface topographic features, such as coronae and mountain belts, is a function of thermal gradient, crustal thickness and lithology, regional stresses, and basal tractions applied to the lithosphere. In this study, we have examined the relative effects of these factors over a period of 500 Ma (presumed to be the mean age of the venusian surface).

  8. The gabbro-eclogite phase transition and the elevation of mountain belts on Venus

    NASA Technical Reports Server (NTRS)

    Namiki, Noriyuki; Solomon, Sean C.

    1992-01-01

    Among the four mountain belts surrounding Lakshmi Planum, Maxwell Montes is the highest and stands up to 11 km above the mean planetary radius and 7 km above Lakshmi Planum. The bulk composition and radioactive heat production of the crust on Venus, where measured, are similar to those of terrestrial tholeiitic basalt. Because the thickness of the low-density crust may be limited by the gabbro-garnet granulite-eclogite phase transitions, the 7-11 km maximum elevation of Maxwell Montes is difficult to understand except in the unlikely situation that the crust contains a large volume of magma. A possible explanation is that the base of the crust is not in phase equilibrium. It has been suggested that under completely dry conditions, the gabbro-eclogite phase transition takes place by solid-state diffusion and may require a geologically significant time to run to completion. Solid-state diffusion is a strongly temperature-dependent process. In this paper we solve the thermal evolution of the mountain belt to attempt to constrain the depth of the gabbro-eclogite transition and thus to assess this hypothesis quantitatively. The one-dimensional heat equation is solved numerically by a finite difference approximation. The deformation of the horizontally shortening crustal and mantle portions of the thermal boundary layer is assumed to occur by pure shear, and therefore the vertical velocity is given by the product of the horizontal strain rate and depth.

  9. The gabbro-eclogite phase transition and the elevation of mountain belts on Venus

    NASA Astrophysics Data System (ADS)

    Namiki, Noriyuki; Solomon, Sean C.

    1992-12-01

    Among the four mountain belts surrounding Lakshmi Planum, Maxwell Montes is the highest and stands up to 11 km above the mean planetary radius and 7 km above Lakshmi Planum. The bulk composition and radioactive heat production of the crust on Venus, where measured, are similar to those of terrestrial tholeiitic basalt. Because the thickness of the low-density crust may be limited by the gabbro-garnet granulite-eclogite phase transitions, the 7-11 km maximum elevation of Maxwell Montes is difficult to understand except in the unlikely situation that the crust contains a large volume of magma. A possible explanation is that the base of the crust is not in phase equilibrium. It has been suggested that under completely dry conditions, the gabbro-eclogite phase transition takes place by solid-state diffusion and may require a geologically significant time to run to completion. Solid-state diffusion is a strongly temperature-dependent process. In this paper we solve the thermal evolution of the mountain belt to attempt to constrain the depth of the gabbro-eclogite transition and thus to assess this hypothesis quantitatively. The one-dimensional heat equation is solved numerically by a finite difference approximation. The deformation of the horizontally shortening crustal and mantle portions of the thermal boundary layer is assumed to occur by pure shear, and therefore the vertical velocity is given by the product of the horizontal strain rate and depth.

  10. Experimental modeling of role of gravity and lateral shortening in Zagros mountain belt

    SciTech Connect

    Koyi, H.

    1988-11-01

    Dynamically scaled analogs of the geologic structures of the Zagros mountain belt are used to argue that different parts of the Zagros Mountains of Iran record different combinations of the effects of a gravity-driven overturn and a southwest-northeast lateral shortening superimposed on the Zagros overturn. Partially scaled material models have been used to simulate the Zagros geodynamics, which involve layer-parallel compression of a 6 to 7 km-thick Phanerozoic carbonate cover containing a pattern of preshortening diapirs. The folds in the Zagros form rapidly (1.5 mm/yr in a 20 to 30 km-wide zone), reactivate some of the preshortening diapirs, and generate new synshortening listric diapirs. A third set of postshortening diapirs rises from the Hormuz decollement behind the fold-thrust front. Model buckle folds superimposed on diapirs or pillows tend to avoid and curve around preshortening diapirs, which flatten in the synclines. Model profiles show that lateral shortening induces residual salt at depth to flow toward and rise through the anticlinal cores as synshortening or postshortening diapirs. The author suggests that any salt pillows in currently diapir-free zones of the Zagros fold-thrust belt may surface as diapirs through the anticlines in the future. 13 figures, 4 tables.

  11. Petrology and geochemistry of metamorphosed komatiites and basalts from the Sula Mountains greenstone belt, Sierra Leone

    NASA Astrophysics Data System (ADS)

    Rollinson, Hugh

    The Sula Mountains greenstone belt is the largest of the late-Archaean greenstone belts in the West African Craton. It comprises a thick (5km) lower volcanic formation and a thinner (2km) upper metasedimentary formation. Komatiites and basalts dominate the volcanic formation and komatiites form almost half of the succession. All the volcanic rocks are metamorphosed to amphibolite grade and have been significantly chemically altered. Two stages of alteration are recognised and are tentatively ascribed to hydrothermal alteration and later regional amphibolite facies metamorphism. Ratios of immobile trace elements and REE patterns preserve, for the most part, original igneous signatures and these are used to identify five magma types. These are: low-Ti komatiites - depleted in light REE; low-Ti komatiites - with flat REE patterns; high-Ti komatiitic basalts - with flat REE; low-Ti basalts - depleted in light REE; high-Ti basalts - with flat REE patterns. Much of the variation between the magma types can be explained in terms of different melt fractions of the mantle source, although there were two separate mantle sources one light REE depleted, the other not. The interleaving of the basalts and komatiites produced by this melting indicates that the two mantle sources were melted simultaneously. The simplest model with which to explain these complex melting processes is during melting within a rising mantle plume in which there were two different mantle compositions. The very high proportion of komatiites in the Sula Mountains relative to other greenstone belts suggests either extensive deep melting and/or the absence of a thick pre-existing crust which would have acted as a ``filter'' to komatiite eruption.

  12. Late-Cainozoic climate change, erosion, and relief of mountain belts: 20 years of chickens and eggs (Ralph Alger Bagnold Medal Lecture)

    NASA Astrophysics Data System (ADS)

    van der Beek, Peter

    2014-05-01

    Over the last two decades, the geoscience community has realized that surface erosion, considered for over a century to respond passively to tectonic forcing, in fact strongly interacts with tectonic processes to produce the variety of deformation styles and relief forms observed in nature. Multiple feedbacks between tectonics, climate and erosion have been identified. In particular, it has been proposed that Cainozoic uplift of mountain belts such as the Himalaya led to global cooling due to CO2 drawdown from the atmosphere by efficient silicate weathering and organic carbon burial. At the same time, however, late-Cainozoic climate change, characterized by overall cooling and increased climatic variability, has been suggested to be responsible for increased erosion rates as well as uplift of mountain peaks through the isostatic response to erosion. Some active mountain belts have even been argued to respond to late-Cainozoic climate change by tectonic reorganisation. Thus, the relative strengths of the tectonic and climatic controls on mountain-belt relief and erosion rates, and how to discriminate between these, have arisen as central questions in tectonic geomorphology since the start of this century. Pliocene-Pleistocene (post-5 Ma) increases in sediment flux have been reported from many major mountain belts such as the Himalaya and the European Alps. It has been suggested this is a global signal in response to increased climatic instability since the Pliocene, although recent work suggests that at least part of the signal may be intrinsic to the nature of the sedimentary record. Analysis of in-situ thermochronology data from the Alps appeared to support the Pliocene increase in erosion rates, which have been linked to increased precipitation subsequent to the Messinian Salinity Crisis and/or the onset of Gulf-Stream circulation. However, recent more detailed work, based on numerical inverse modelling and the use of new high-resolution thermochronometers

  13. Activating main belt comets by collisions

    NASA Astrophysics Data System (ADS)

    Maindl, T. I.; Haghighipour, N.; Schäfer, C.; Speith, R.

    2016-02-01

    Since their identification as a new class of bodies by Hsieh and Jewitt in 2006 active asteroids (or Main Belt Comets, MBCs) have attracted a great deal of interest. Given that sublimation of volatile material (presumably water-ice) drives MBC activity, these bodies are probable candidates for delivering a significant amount of Earth's water. Dynamical studies suggest in-situ formation of MBCs as the remnants of the break-up of large icy asteroids. Also, collisions between MBCs and small objects might have exposed sub-surface water-ice triggering the cometary activity of these bodies. In order to advance the effort of understanding the nature of MBC activation, we have investigated these collision processes by simulating the impacts in detail using a smooth particle hydrodynamics (SPH) approach that includes material strength and fracture models. Our simulations cover a range of impact velocities (between 0.5 km/s and 5.3 km/s) and angles, allowing m-sized impactors to erode enough of an MBC's surface to expose volatiles and trigger its activation. We also varied the material strength of the active asteroid's surface to study its influence on crater depths and shapes. As expected, depending on the impact energy, impact angle, and MBC's material strength we observe different crater depths. Across all scenarios however, our results show that the crater depths do not exceed a few meters. This implies that if the activity of MBCs is due to sublimating water-ice, ice has to exist in no deeper than a few meters from the surface.

  14. Crustal Deformation around Zhangjiakou-Bohai Seismically Active Belt

    NASA Astrophysics Data System (ADS)

    Jin, H.; Fu, G.; Kato, T.

    2011-12-01

    Zhangjiakou-Bohai belt is a seismically active belt located in Northern China around Beijing, the capital of China. Near such a belt many great earthquakes occurred in the past centuries (e.g. the 1976 Tanshan Ms7.8 earthquake, the 1998 Zhangbei Ms6.2 earthquake, etc). Chinese Government established dense permanent and regional Global Positioning System (GPS) stations in and near the area. We collected and analyzed all the GPS observation data between 1999 and 2009 around Zhangjiakou-Bohai seismic belt, and obtained velocities at 143 stations. At the same time we investigated Zhangjiakou-Bohai belt slip rate for three profiles from northwest to southeast, and constructed a regional strain field on the Zhangjiakou-Bohai seismic belt region by least-square collocation. Based on the study we found that: 1) Nowadays the Zhangjiakou-Bohai seismic belt is creeping with left-lateral slip rate of 2.0mm~2.4mm/a, with coupling depth of 35~50km; 2) In total, the slip and coupling depth of the northwestern seismic belt is less than the one of southeast side; 3) The maximum shear strain is about 3×10-8 at Beijing-Tianjin-Tangshan area.

  15. Geology of the Flat Swamp Mountain caldera and related rocks, Carolina slate belt, central North Carolina

    SciTech Connect

    Butler, J.R. . Dept. of Geology)

    1994-03-01

    The Flat Swamp Member (FSM) of the Cid Formation (Late Proterozoic) and related volcanogenic deposits in the Carolina slate belt of central North Carolina constitute a submarine caldera complex, mildly deformed and metamorphosed to lower greenschist facies. The intracaldera facies, including mudflow breccias, ashfall tuffs, pyroclastic flows and lava flows, are 1.2 to 1.8 km thick in the Denton area. The FSM thins abruptly near Badin, passing laterally into extracaldera facies less than 150 m thick of coarse- to fine-grained crystal-rich ashfall tuffs with an upper unit of extremely fine-grained devitrified vitric tuffs. The thickness and average grainsize decrease to the south and east, until the FSM merges with adjacent mudstones. The Morrow Mountain Rhyolite includes bodies of homogeneous rhyolite as much as several km across emplaced within the FSM and stratigraphically lower units, interpreted to be shallow intrusions and some surface-breaking lava domes, emplaced at depths from 0 to 3 km within the caldera and along the ring-fractures. The FSM has been mapped over an area of about 2,400 km[sup 2], and it forms a time-constant layer useful in elucidating slate belt stratigraphy.

  16. The role of extensional inheritance and surface processes on mountain belt evolution

    NASA Astrophysics Data System (ADS)

    Erdos, Zoltan; Huismans, Ritske S.; van der Beek, Peter

    2015-04-01

    The crustal structure of collisional orogens around the world shows a wide range of deformation styles from narrow, asymmetric doubly vergent wedges like the Pyrenees to wide, plateau-like orogens such as the Zagros mountain belt in Iran. Inherited structures and surface processes are widely regarded as factors playing significant role in the evolution of such mountain belts. These parameters have been studied extensively throughout the last decades, yet questions still remain about their exact effects on the style of orogenic development. We use lithospheric scale plane-strain thermo-mechanical model experiments to study the effects of extensional inheritance and surface processes on the internal structure of contractional orogens and their foreland basins. Extensional inheritance is modeled explicitly by forward modeling the formation of a rift basin before reversing the velocity boundary conditions to model its inversion. Surface processes are modeled through the combination of a simple sedimentation algorithm, where all negative topography is filled up to a prescribed reference level, and an elevation-dependent erosion model. We test the sensitivity of our models to the amount of crustal extension, and to the length of post-rift thermal relaxation. Moreover, the interaction of thin-skinned and thick-skinned tectonics is explored with the use of a shallow frictionally weak detachment at the base of a pre-deformation sedimentary layer. Our results show that extensional inheritance facilitates the propagation of basement deformation in the retro-wedge and increases the width of the orogen. Additionally, sedimentation increases the length-scale of both thin-skinned and thick-skinned thrust sheets and results in a wider orogen while erosion helps to localize deformation resulting in a narrower orogen. However, the length of post-rift thermal relaxation seems to have very little effect on the following mountain building. A comparison of the modeled behaviors to the

  17. Antarctic NAT PSC Belt of June 2003: Observational Validation of the Mountain Wave Seeding Hypothesis

    NASA Technical Reports Server (NTRS)

    Eckermann, S. D.; Hoffmann, L.; Hoepfner, M.; Wu, D. L.; Alexander, M. J.

    2009-01-01

    Satellite observations of polar stratospheric clouds (PSCs) over Antarctica in June 2003 revealed small nitric acid trihydrate (NAT) particles forming suddenly along the vortex edge. Models suggest the trigger was mountain waves over the Antarctic Peninsula (AP) forming ice for NAT nucleation. We test this hypothesis by analyzing perturbations in stratospheric radiances from the Atmospheric Infrared Sounder (AIRS). AIRS data show mountain waves over the AP on 10-14 June, with no resolved wave activity before or after. Peak wave temperature amplitudes derived from independent 40 hPa channels all return values of 10-12 K, in agreement with values used to model this NAT event. These observations support a NAT wake from a small region of mountain wave activity over the AP as the source of this circumpolar NAT outbreak.

  18. The growth of a mountain belt forced by base-level fall: Tectonics and surface processes during the evolution of the Alborz Mountains, N Iran

    NASA Astrophysics Data System (ADS)

    Ballato, Paolo; Landgraf, Angela; Schildgen, Taylor F.; Stockli, Daniel F.; Fox, Matthew; Ghassemi, Mohammad R.; Kirby, Eric; Strecker, Manfred R.

    2015-09-01

    The idea that climatically modulated erosion may impact orogenic processes has challenged geoscientists for decades. Although modeling studies and physical calculations have provided a solid theoretical basis supporting this interaction, to date, field-based work has produced inconclusive results. The central-western Alborz Mountains in the northern sectors of the Arabia-Eurasia collision zone constitute a promising area to explore these potential feedbacks. This region is characterized by asymmetric precipitation superimposed on an orogen with a history of spatiotemporal changes in exhumation rates, deformation patterns, and prolonged, km-scale base-level changes. Our analysis suggests that despite the existence of a strong climatic gradient at least since 17.5 Ma, the early orogenic evolution (from ∼36 to 9-6 Ma) was characterized by decoupled orographic precipitation and tectonics. In particular, faster exhumation and sedimentation along the more arid southern orogenic flank point to a north-directed accretionary flux and underthrusting of Central Iran. Conversely, from ∼6 to 3 Ma, erosion rates along the northern orogenic flank became higher than those in the south, where they dropped to minimum values. This change occurred during a ∼3-Myr-long, km-scale base-level lowering event in the Caspian Sea. We speculate that mass redistribution processes along the northern flank of the Alborz and presumably across all mountain belts adjacent to the South Caspian Basin and more stable areas of the Eurasian plate increased the sediment load in the basin and ultimately led to the underthrusting of the Caspian Basin beneath the Alborz Mountains. This underthrusting in turn triggered a new phase of northward orogenic expansion, transformed the wetter northern flank into a new pro-wedge, and led to the establishment of apparent steady-state conditions along the northern orogenic flank (i.e., rock uplift equal to erosion rates). Conversely, the southern mountain front

  19. Young orogenic gold mineralisation in active collisional mountains, Taiwan

    NASA Astrophysics Data System (ADS)

    Craw, Dave; Upton, Phaedra; Yu, Bing-Sheng; Horton, Travis; Chen, Yue-Gau

    2010-10-01

    Gold-bearing vein systems in the high mountains of Taiwan are part of the youngest tectonic-hydrothermal system on Earth. Tectonic collision initiated in the Pliocene has stacked Eocene-Miocene marine sedimentary rocks to form steep mountains nearly 4 km high. Thinner portions of the sedimentary pile (˜5 km) are currently producing hydrocarbons in a fold and thrust belt, and orogenic gold occurs in quartz veins in thicker parts of the pile (˜10 km) in the Slate Belt that underlies the mountains. Metamorphic fluids (2-5 wt.% NaCl equivalent) are rising from the active greenschist facies metamorphic zone and transporting gold released during rock recrystallisation. Metamorphic fluid flow at the Pingfengshan historic gold mine was focussed in well-defined (4 km3) fracture zones with networks of quartz veins, whereas large surrounding volumes of rock are largely unveined. Gold and arsenopyrite occur in several superimposed vein generations, with ankeritic alteration of host rocks superimposed on chlorite-calcite alteration zones as fluids cooled and became out of equilibrium with the host rocks. Mineralising fluids had δ18O near +10‰, δ13C was between -1‰ and -6‰ and these fluids were in isotopic equilibrium with host rocks at ˜350°C. Ankeritic veins were emplaced in extensional sites in kink fold axial surfaces, formed as the rock mass was transported laterally from compressional to extensional regimes in the orogen. Rapid exhumation (>2 mm/year) of the Slate Belt is causing a widespread shallow conductive thermal anomaly without igneous intrusions. Meteoric water is penetrating into the conductive thermal anomaly to contribute to crustal fluid flow and generate shallow boiling fluids (˜250°C) with fluid temperature greater than rock temperature. The meteoric-hydrothermal system impinges on, but causes only minor dilution of, the gold mineralisation system at depth.

  20. Factors controlling the tectonic inversion of the Pyrenean mountain belt : from observations to modelling

    NASA Astrophysics Data System (ADS)

    Jammes, S.; Huismans, R. S.

    2012-04-01

    Local inherited weaknesses and regional inherited crust and mantle lithosphere structure are expected to control the structural style of tectonic inversion of rift zones and passive margins. However it is still unclear to which extent structural inheritance plays a role during inversion tectonics and contributes to the structural style of inversion. Here we focus in the context of the Topo-Europe project PYRTEC on the Pyrenean-Cantabrian mountain belt, which is very well studied. The moderate inversion, the good preservation of both pre and syn-orogenic strata and the excellent geological and geophysical data set make this chain one of the best candidates to investigate these questions. The influence of inherited crustal heterogeneities, denudation, subcrustal loads and crustal mechanical properties on the deformation style of the Pyrenean chain has been already investigated by Beaumont et al. [2000] with a comparison between observations and geodynamical models. The main conclusion of their study is that the asymmetry of the Pyrenean double wedge and its morphological evolution is a consequence of the asymmetric distribution of inherited crustal heterogeneity suggesting that the tectonic style of the Pyrenees is strongly controlled by the inversion of previous extensional features. Here we use lithosphere scale 2D numerical thermo-mechanical models to investigate the effect of rift inheritance on mountain building style with a procedure coined accordion tectonics. The formation of rift basin margin is explicitly modeled and the results are then used as initial condition for the lithospheric scale inversion. The purpose of our work is to explore to which extent local inherited weaknesses and regional inherited crust and mantle lithosphere structure play a role during inversion tectonics and contribute to the structural style of Pyrenean chain.

  1. Main-belt comets: sublimation-driven activity in the asteroid belt

    NASA Astrophysics Data System (ADS)

    Hsieh, Henry H.

    2016-01-01

    Our knowledge of main-belt comets (MBCs), which exhibit comet-like activity likely due to the sublimation of volatile ices, yet orbit in the main asteroid belt, has increased greatly since the discovery of the first known MBC, 133P/Elst-Pizarro, in 1996, and their recognition as a new class of solar system objects after the discovery of two more MBCs in 2005. I review work that has been done over the last 10 years to improve our understanding of these enigmatic objects, including the development of systematic discovery methods and diagnostics for distinguishing MBCs from disrupted asteroids (which exhibit comet-like activity due to physical disruptions such as impacts or rotational destabilization). I also discuss efforts to understand the dynamical and thermal properties of these objects.

  2. Mountain building processes in intracontinental oblique deformation belts: Lessons from the Gobi Corridor, Central Asia

    NASA Astrophysics Data System (ADS)

    Cunningham, Dickson

    2013-01-01

    amongst a complex network of faults. Therefore, earthquake prediction is likely to be more complex than in plate boundary settings and extrapolation of derived Late Quaternary fault slip rates is not straightforward. Modern mountain building within the Gobi Corridor demonstrates that reactivation of ancient accretionary and collisional orogens within continental interiors can play an important role in continental evolution and the life cycle of orogenic belts.

  3. FCaZm intelligent recognition system for locating areas prone to strong earthquakes in the Andean and Caucasian mountain belts

    NASA Astrophysics Data System (ADS)

    Gvishiani, A. D.; Dzeboev, B. A.; Agayan, S. M.

    2016-07-01

    The fuzzy clustering and zoning method (FCAZm) of systems analysis is suggested for recognizing the areas of the probable generation of the epicenters of significant, strong, and the strongest earthquakes. FCAZm is a modified version of the previous FCAZ algorithmic system, which is advanced by the creation of the blocks of artificial intelligence that develop the system-forming algorithms. FCAZm has been applied for recognizing areas where the epicenters of the strongest ( M ≥ 73/4) earthquakes within the Andes mountain belt in the South America and significant earthquakes ( M ≥ 5) in the Caucasus can emerge. The reliability of the obtained results was assessed by the seismic-history type control experiments. The recognized highly seismic zones were compared with the ones previously recognized by the EPA method and by the initial version of the FCAZ system. The modified FCAZm system enabled us to pass from simple pattern recognition in the problem of recognizing the locations of the probable emergence of strong earthquakes to systems analysis. In particular, using FCAZm we managed to uniquely recognize a subsystem of highly seismically active zones from the nonempty complement using the exact boundary.

  4. Hyperextension, rifted margin geometry and its incorporation into mountain belts: Insights from the western Alps

    NASA Astrophysics Data System (ADS)

    Butler, R.

    2012-12-01

    Collision orogens are the products of inversion of rifted margins, and components of these rifted margins can be recognised in mountain belts. The roles of pre-existing heterogeneities in localising contractional deformation in thrust belts are well-studied. However, the distribution of hyperextended continental lithosphere at rifted margins, especially the presence of substantial tracts of hydrated upper mantle, is likely to have a strong bearing on how orogens evolve. These issues are developed here using examples drawn from the western Alps. Quantifying the magnitude and distribution of crustal thinning prior to orogenesis is critical for crustal balancing and the related prediction of subduction of continental crust. By invoking pre-orogenic hyperextension it is now possible to balance crustal sections western Alps so that the seismically imaged crust is consistent with estimates of orogenic contraction. Hitherto the same sections have required long-term subduction of continental crust - although these inferred subducted tracts have resisted seismic imaging. Transitional parts of the ancestral rifted margin, where there are rapid changes in basin geometry (Dauphine-SubBrianconnais, Vocontian flanks), appear to focus weak inversion ahead of the developing orogen. Furthermore, the style of rifting (depth-heterogeneous vs quasi-uniform kinematics) with the relative importance of lithospheric detachments and hydrated, weak upper mantle can influence the extent to which continental crust can later be subducted. That the continental crust of the internal basement massifs (Dora Maira, Gran Paradiso) experienced transient subduction (HP peaks of 2-4 GPa) implies initially strong coupling with underlying mantle lithosphere (followed by decoupling for exhumation). These parts of the ancestral continental margin are thus likely to have stretched quasi-uniformly. However, those parts of the margin that stretched heterogeneously (rider blocks that rested on hydrated mantle

  5. The Zagros fold-thrust belt : constraints on timing and mountain building

    NASA Astrophysics Data System (ADS)

    Mouthereau, Frederic

    2010-05-01

    The Zagros Mountains form a broad orogenic domain, approximately 2000 km long, in front of the Turkish-Iranian plateau. Its position at the crossroad between Tibet, Africa and the Mediterranean region and its development at times of Tertiary climatic changes make the Zagros fold-belt an exceptional site to study the drivers of global climate changes associated with Africa-Arabia/Eurasia plate convergence. The Zagros fold belt is also particularly well-known for its remarkable large fold train. In this study, we review the recent findings on the Zagros geology as well as the timing and mechanical model constraints on the Zagros mountain building. According to recent magnetostratigraphic dating of the Zagros foreland-basin deposits, collision-related folding of the Arabian margin started ca. 13.9 Ma. U-Th(He) thermochronological data provided consistent age for thrusting in the High Zagros. Because facies/sedimentological studies reveal that the first conglomeratic formation of this age (Bakhtyari Formation) were deposited below sea level, the onset of Zagros uplift together with the southern Iranian Plateau uplift now at ~2000 m asl should necessarily be younger than 13.9 Ma. The latest major erosional-depositional event, roughly dated between 3 Ma to 0.8-0.5 Ma, is outlined by the deposition of conglomerates overlying unconformably the folded cover. In the Fars region river network is characterized by a lack of evidence for transverse rivers cutting through folds. This particular drainage pattern suggests that rivers are strongly controlled by the folds growth. The present-day shortening rates of ~7 mm/Myr across the Zagros, with the minimum age constraints of 13.9 Ma predict ~97 km of total shortening. However, less than half, i.e. 17-45 km can be reconstructed from balanced cross-sections. This could be explained by assuming that shortening was accommodated, for instance, by underplating beneath the Iranian plate or the Iranian plateau. Cover folding appears

  6. Evidence for fluid flow in ductile shear zones, Granite Wash Mountains, Maria fold and thrust belt

    SciTech Connect

    Marin, B.A.; Mosher, S. . Dept. of Geological Sciences)

    1993-04-01

    Synkinematic fluids that accompanied Mesozoic (D2) deformation in the Granite Wash Mountains, eastern Maria fold and thrust belt, had profound effects on the metamorphic mineralogy and deformation mechanisms of Paleozoic metsedimentary rocks. The D2 thrusts are discrete brittle faults that commonly bound highly sheared, ductilely deformed rocks. These low-angle faults cross cut a vertical section of Paleozoic and Mesozoic supracrustal rocks that were multiply repeated and upturned by earlier Mesozoic deformation, D1. Kinematic analysis of a series of these ductile shear zones has confirmed that the dominant sense of motion during thrusting was to the SW, however, some isolated kinematic indicators and indicators along the lowest zone suggest NE-thrusting. Microstructures in samples collected both within D2 ductile shear zones and outside D2 zones show fluids played an important role in D2 deformation. The abundant evidence for fluids along D2 ductile shear zones includes: quartz veins in the Kaibab Fm (a dolomitic marble), zones of metasomatic alteration ( bleached'' zones) within D2 zones, an increase in the abundance of metamorphic minerals within D2 zones, and the presence of synkinematic wollastonite in silicones limestones of the Redwall Fm. The most dramatic and significant effect of synkinematic fluids in on the style of deformation mechanisms operating during thrusting. Evidence for intracrystalline plastic deformation and rotational recrystallization is not well-developed: instead, microstructures are dominated by migrational recrystallization fabrics. In some samples, quartz grain boundaries have migrated over a preexisting foliation defined by aligned micas, indicating that grain boundaries were highly mobile. Fluid-enhanced grain boundary mobility has allowed internally deformed grains or parts of grains to be consumed rapidly with no or little record of the deformation left behind.

  7. The many impacts of building mountain belts on plate tectonics and mantle flow

    NASA Astrophysics Data System (ADS)

    Yamato, Philippe; Husson, Laurent

    2015-04-01

    During the Cenozoic, the number of orogens on Earth increased. This observation readily indicates that in the same time, compression in the lithosphere became gradually more and more important. Such an increase of stresses in the lithosphere can impact on plate tectonics and mantle dynamics. We show that mountain belts at plate boundaries increasingly obstruct plate tectonics, slowing down and reorienting their motions. In turn, this changes the dynamic and kinematic surface conditions of the underlying flowing mantle. Ultimately, this modifies the pattern of mantle flow. This forcing could explain many first order features of Cenozoic plate tectonics and mantle flow. Among these, one can cite the compression of passive margins, the important variations in the rates of spreading at oceanic ridges, or the initiation of subduction, the onset of obduction, for the lithosphere. In the mantle, such change in boundary condition redesigns the pattern of mantle flow and, consequently, the oceanic lithosphere cooling. In order to test this hypothesis we first present thermo-mechanical numerical models of mantle convection above which a lithosphere rests. Our results show that when collision occurs, the mantle flow is highly modified, which leads to (i) increasing shear stresses below the lithosphere and (ii) to a modification of the convection style. In turn, the transition between a 'free' convection (mobile lid) and an 'upset' convection (stagnant -or sluggish- lid) highly impacts the dynamics of the lithosphere at the surface of the Earth. Thereby, on the basis of these models and a variety of real examples, we show that on the other side of a collision zone, passive margins become squeezed and can undergo compression, which may ultimately evolve into subduction or obduction. We also show that much further, due to the blocking of the lithosphere, spreading rates decrease at the ridge, a fact that may explain a variety of features such as the low magmatism of ultraslow

  8. When mountain belts disrupt mantle flow: from natural evidences to numerical modelling

    NASA Astrophysics Data System (ADS)

    Yamato, Philippe; Husson, Laurent; Guillaume, Benjamin

    2016-04-01

    During the Cenozoic, the number of orogens on Earth increased. This observation readily indicates that in the same time, compression in the lithosphere became gradually more and more important. Here, we show that such mountain belts, at plate boundaries, increasingly obstruct plate tectonics, slowing down and reorienting their motions. In turn, it changes the dynamic and kinematic surface conditions of the underlying flowing mantle, which ultimately modifies the pattern of mantle flow. Such forcing could explain many first order features of Cenozoic plate tectonics and mantle flow. Among others, at lithospheric scale, one can cite the compression of passive margins, the important variations in the rates of spreading at oceanic ridges, the initiation of subductions, or the onset of obductions. In the mantle, such changes in boundary conditions redesign the flow pattern and, consequently, disturb the oceanic lithosphere cooling. In order to test this hypothesis we first present thermo-mechanical numerical models of mantle convection above which a lithosphere is resting on top. Our results show that when collision occurs, the mantle flow is strongly modified, which leads to (i) increasing shear stresses below the lithosphere and (ii) a modification of the convection style. In turn, the transition between a "free" convection (mobile lid) and a "disturbed" convection (stagnant - or sluggish - lid) highly impacts the dynamics of the lithosphere at the surface. Thereby, on the basis of these models and a variety of real examples, we show that on the other side of a lithosphere presenting a collision zone, passive margins become squeezed and can undergo compression, which may ultimately evolve into subduction initiation or obduction. We also show that much further, due to the blocking of the lithosphere, spreading rates decrease at the ridge, which may explain a variety of features such as the low magmatism of ultraslow spreading ridges or the departure of slow spreading

  9. Microbial activity at Yucca Mountain

    SciTech Connect

    Horn, J.M.; Meike, A.

    1995-09-25

    The U.S. Department of Energy is engaged in a suitability study for a potential geological repository at Yucca Mountain, Nevada, for the containment and storage of commercially generated spent fuel and defense high-level nuclear waste. There is growing recognition of the role that biotic factors could play in this repository, either directly through microbially induced corrosion (MIC), or indirectly by altering the chemical environment or contributing to the transport of radionuclides. As a first step toward describing and predicting these processes, a workshop was held on April 10-12, 1995, in Lafayette, California. The immediate aims of the workshop were: (1) To identify microbially related processes relevant to the design of a radioactive waste repository under conditions similar to those at Yucca Mountain. (2) To determine parameters that are critical to the evaluation of a disturbed subterranean environment. (3) To define the most effective means of investigating the factors thus identified.

  10. Crustal structure of mountain belts and basins: Industry and academic collaboration at Cornell

    SciTech Connect

    Allmendinger, R.; Barazangi, M.; Brown, L.

    1995-08-01

    Interdisciplinary investigations of the large-scale structure and evolution of key basins and orogenic belts around the world are the focal point of academic-industry interaction at Cornell. Ongoing and new initiatives with significant industry involvement include: Project INDEPTH (Interdisciplinary Deep Profiling of Tibet and the Himalayas), a multinational effort to delineate deep structure across the type example of active continent-continent collision. 300 km of deep reflection profiling was collected across the Himalaya: and southern Tibet Plateau in 1992 and 1994. CAP (Cornell Andes Project), a long-standing interdisciplinary effort to understand the structure and evolution of the Andes, with a focus on Argentina, Chile and Bolivia. A deep reflection profile is tentatively planned for 1997. Intra-plate Orogeny in the Middle East and North Africa is the focus of multidisciplinary regional syntheses of existing seismic reflection and other databases in Syria (Palmyrides)and Morocco (Atlas), with an emphasis on reactivation and inversion tectonics. Project URSEIS (Urals Reflection Seismic Experiment and Integrated Studies) is a collaboration with EUROPROBE to collect 500 km of vibroseis and dynamite deep reflection profiling across the southern Urals in 1995. Project CRATON, an element in COCORP`s systematic exploration of the continental US, is a nascent multi-disciplinary effort to understand the buried craton of the central US and the basins built upon it. Global Basins Research Network (GBRN) is a diversified observational and computational effort to image and model the movement of pore fluids in detail and on a regional scale for a producing oil structure in the Gulf of Mexico.

  11. Measurement of tectonic surface uplift rate in a young collisional mountain belt

    USGS Publications Warehouse

    Abbott, L.D.; Silver, E.A.; Anderson, R. Scott; Smith, R.; Ingle, J.C.; Kling, S.A.; Haig, D.; Small, E.; Galewsky, J.; Sliter, W.

    1997-01-01

    Measurement of the rate of tectonically driven surface uplift is crucial to a complete understanding of mountain building dynamics. The lack of a suitable rock record typically prevents determination of this quantity, but the unusual geology of Papua New Guinea's Finisterre mountains makes measurement of this rate possible. The tectonic surface uplift rate at the Finisterre range is 0.8-2.1 mm yr-1, approximately that expected to arise from crustal thickening.

  12. A New Look at the Lithospheric Structure of the Southern Rocky Mountains and the Cheyenne Belt Suture

    NASA Astrophysics Data System (ADS)

    Rumpfhuber, E.; Keller, G.; Velasco, A. A.

    2008-12-01

    We have used the Southern Rocky Mountains and the Cheyenne belt suture as a test bed for integrating tectonic scale controlled- and passive-source seismic datasets. The CD-ROM 1999 experiment in the western U.S. was an example of a multi-discipline geoscientific experiment, including a 1000 km long controlled-source seismic line that extended from central Wyoming to central New Mexico. In addition, two passive source seismic transacts focusing on the Cheyenne belt and the Jemez lineament were deployed for one year along the controlled-source seismic (CSS) line. For the large-scale refraction/wide-angle reflection seismic dataset, we applied a new picking strategy and forward-modeled and inverted the resulting seismic picks for a 2-D velocity and interface model of the area. Furthermore, we identified and picked the S-wave phases that were present, and established an independent S-wave velocity model, which allowed us to construct the Vp/Vs and Poisson's ratios. We calculated teleseismic receiver functions for the area based on northern passive seismic transect, which targeted the Cheyenne belt. We then applied a slant stacking technique to determine crustal thickness and Vp/Vs ratios, as well as common conversion point (CCP) stacking and migration techniques, which provide us with additional two-dimensional images of the target area. Only the joint interpretation of both the CSS and receiver function results enabled us to undertake a detailed interpretation of the Cheyenne belt area, which constitutes the transition zone between the 2.7 Ga Archean Wyoming craton to the north and the Proterozoic terranes to the south. The crustal structure is distinctively different between these two areas. A strong mid-crustal layer underneath the Wyoming craton was confirmed, which was identified in the earlier Deep Probe seismic experiment. Furthermore, this layer terminates at depth ~100 km north of the Cheyenne belt, which represents the surface expression of the suture. Our

  13. The Kuqa late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains

    NASA Astrophysics Data System (ADS)

    Li, Yue-Jun; Wen, Lei; Zhang, Hong-An; Huang, Tai-Zhu; Li, Hui-Li; Shi, Yuan-Yuan; Meng, Qing-Long; Peng, Geng-Xin; Huang, Shao-Ying; Zhang, Qiang

    2015-10-01

    The Kuqa fold-thrust belt (KFTB), a late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains, consists of several deformation zones trending nearly W-E. The main décollement fault of the KFTB gradually rises southwards. There are three regional main décollement faults in the Triassic dark mudstone, Paleogene gypsum salt (Kumugeliemu Formation), and Neogene gypsum salt (Jidike Formation), respectively, and possibly a fourth in the Jurassic coalbed. Laterally, thin-skinned structures are developed in the main segments of the KFTB, whereas thick-skinned structures are in the root zone. Vertically, the structural deformation above the Cenozoic gypsum-salt layers (Paleogene gypsum salt in the middle segment of the KFTB and Neogene gypsum salt in the eastern segment) is characterized by décollement folding, whereas that below is characterized by thrusting. The KFTB was resulted from the late Cenozoic intra-continental orogeny in the Tian Shan area under the far-field effect of the India-Asia collision. The deformation of KFTB began (folding and thrusting) ca. 23 Ma, when the far-field effect of the India-Asia collision reached the Tian Shan area. The deformation of KFTB accelerated ca. 10, 5-2, and 1-0 Ma. In general, the evolution of the KFTB is forward propagating, and the hinter parts of the KFTB continue to deform, while its front propagates southwards.

  14. The Kuqa late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains

    NASA Astrophysics Data System (ADS)

    Li, Yue-Jun; Wen, Lei; Zhang, Hong-An; Huang, Tai-Zhu; Li, Hui-Li; Shi, Yuan-Yuan; Meng, Qing-Long; Peng, Geng-Xin; Huang, Shao-Ying; Zhang, Qiang

    2016-07-01

    The Kuqa fold-thrust belt (KFTB), a late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains, consists of several deformation zones trending nearly W-E. The main décollement fault of the KFTB gradually rises southwards. There are three regional main décollement faults in the Triassic dark mudstone, Paleogene gypsum salt (Kumugeliemu Formation), and Neogene gypsum salt (Jidike Formation), respectively, and possibly a fourth in the Jurassic coalbed. Laterally, thin-skinned structures are developed in the main segments of the KFTB, whereas thick-skinned structures are in the root zone. Vertically, the structural deformation above the Cenozoic gypsum-salt layers (Paleogene gypsum salt in the middle segment of the KFTB and Neogene gypsum salt in the eastern segment) is characterized by décollement folding, whereas that below is characterized by thrusting. The KFTB was resulted from the late Cenozoic intra-continental orogeny in the Tian Shan area under the far-field effect of the India-Asia collision. The deformation of KFTB began (folding and thrusting) ca. 23 Ma, when the far-field effect of the India-Asia collision reached the Tian Shan area. The deformation of KFTB accelerated ca. 10, 5-2, and 1-0 Ma. In general, the evolution of the KFTB is forward propagating, and the hinter parts of the KFTB continue to deform, while its front propagates southwards.

  15. Modeling of thermo-rheological structure of lithosphere under the foreland basin and mountain belt of Taiwan

    NASA Astrophysics Data System (ADS)

    Zhou, Di; Yu, Ho-Shing; Xu, He-Hua; Shi, Xiao-Bin; Chou, Ying-Wei

    2003-10-01

    The system of Taiwan mountain belt and the West Taiwan foreland basin is a manifestation of the collision between eastern Asian continental margin and the Philippine volcanic arc. It provides an ideal place for the study of the flexure behavior of lithosphere under the mountain-basin system. The paper presents results of thermal and rheological modeling of the system along Profile B, which extends 200 km in a NW-SE direction from the Taiwan Strait across the foreland basin and mountain range to the Longitudinal Valley. Along the profile, the crustal structure is constrained by wide-angle seismic and gravity data as well as P-wave tomography, while the structure of the foreland basin is constrained by multichannel seismic and drilling. Assuming that a steady-state deformation has proceeded in Taiwan since the collision of the Luzon Arc with the SE Eurasian margin at 6.5 Ma, the present-day thermal and rheological structures of the lithosphere are modeled by finite element analysis. The base of lithosphere is assumed to be isothermal, with a temperature of 1300 °C. The interior heat source consists of radiogenic heating, frictional heating on thrust faults and basal decollement, and body heating by internal friction within thrust sheets. In addition to conduction, the heat convection is carried out by the subduction of the Eurasian margin, the exhumation and erosion in the mountain range, and the sedimentation in the foreland basin. Thermal parameters are carefully selected and updated based on available data on surface heat flow, downhole thermal gradient, and thermal conductivity from Taiwan and nearby regions. The mechanical parameters are determined based on regional geology. The resulting thermal model predicts well the elevated surface heat flow in the mountain range and the depressed surface heat flow in the thrust front. A high-temperature core of >500 °C appears in the bottom of thrust sheets and the uppermost upper crust. Sensitivity analysis indicates

  16. The Jamestown Ophiolite Complex, Barberton mountain belt - A section through 3.5 Ga oceanic crust

    NASA Technical Reports Server (NTRS)

    De Wit, Maarten J.; Hart, Roger A.; Hart, Rodger J.

    1987-01-01

    The Jamestown Ophiolite Complex of the Barberton greenstone belt, South Africa, is investigated, and the intrusive nature of mafic-ultramafic units from the Komati and Kromberg formations into overlying pillow lavas and sediments is documented. Evidence is presented for multiple intrusive events within the igneous sections, including crosscutting intrusives, multiple injection of magma in the Komati section, and sheeted intrusions in the Kromberg section. The thinness of the Jamestown complex suggests that, locally at least, the ca 3.5 Ga oceanic crust was also thin, consistent with the regionally extensive metasomatic alteration.

  17. The Satah Mountain and Baldface Mountain volcanic fields: Pleistocene hot spot volcanism in the Anahim Volcanic Belt, west-central British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Kuehn, Christian; Guest, Bernard; Russell, James K.; Benowitz, Jeff A.

    2015-03-01

    The Satah Mountain and Baldface Mountain volcanic fields (SMVF, BMVF) comprise more than three dozen small volcanic centers and erosional remnants thereof. These fields are located in the Chilcotin Highland of west-central British Columbia, Canada, and are spatially associated with the Anahim Volcanic Belt (AVB), a linear feature of alkaline to peralkaline plutonic and volcanic centers of Miocene to Holocene ages. The AVB has been postulated to be the track of a hot spot passing beneath the westward moving Cordilleran lithosphere. We test the AVB hot spot model by applying whole-rock 40Ar/39Ar geochronology ( n = 24) and geochemistry. Whole-rock chemical compositions of volcanic rock samples ( n = 59) from these two fields suggest a strong geochemical affinity with the nearby Itcha Range shield volcano; however, SMVF and BMVF centers are mostly small in volume (<1 km3) and differ in composition from one another, even where they are in close spatial proximity. Trace element and REE patterns of mafic AVB lavas are similar to ocean island basalts (OIB), suggesting a mantle source for these lavas. The age ranges for the SMVF ( n = 11; ~2.21 to ~1.43 Ma) and BMVF ( n = 7; ~3.91 to ~0.91 Ma) are largely coeval with the Itcha Range. The distribution of volcanoes in these two volcanic fields is potentially consistent with the postulated AVB hot spot track. Eruption rates in the SMVF were high enough to build an elongated ridge that deviates from the E-W trend of the AVB by almost 90°. This deviation might reflect the mechanisms and processes facilitating magma generation and ascent through the lithosphere in this tectonically complex region and may also indicate interaction of the potential hot spot with (pre)existing fracture systems in vicinity of the Itcha Range.

  18. The gabbro-eclogite phase transition and the elevation of mountain belts on Venus

    NASA Technical Reports Server (NTRS)

    Namiki, Noriyuki; Solomon, Sean C.

    1993-01-01

    The hypothesis is explored that the crust-mantle boundary of Venus is not in phase equilibrium but rather is rate-limited by the temperature-dependent volume diffusion of the slowest ionic species. The 1D thermal evolution problem is solved assuming that the mountains formed by uniform horizontal shortening of the crust and the lithospheric mantle at a constant rate. The time-dependent density structure and surface elevation are calculated by assuming a temperature-dependent reaction rate and local Airy isostatic compensation. For a horizontal strain rate of 10 exp -15/s or greater, the temperature increase at the base of the crust during mountain formation is modest to negligible, the deepening lower crust is metastable, and the surface elevation increases as the crust thickens. For strain rates less than 10 exp -16/s, crustal temperature increases with time because of internal heat production and the lower crust is more readily transformed to the dense eclogite assemblage. For such models, a maximum elevation is reached during crustal shortening.

  19. New views on the structure and evolution of the Andes-Altiplano orogenic system: Are collision- and subduction-type mountain belts mechanically different?

    NASA Astrophysics Data System (ADS)

    Riesner, M.; Armijo, R.; Lacassin, R.; Simoes, M.; Carrizo, D.; Fuentes, G.

    2014-12-01

    The Andes-Altiplano orogenic system, one of the most significant topographic feature on Earth, is the case example of subduction-type mountain belts. This latter conceptual model considers that the overall structure of the mountain belt forms antithetic to the subduction zone which marks the main plate interface, and as such poses several mechanical issues. Recent studies challenged this view, by proposing a model of the Andes involving an embryonic west-vergent intracontinental subduction, synthetic to the subduction zone and thus geometrically comparable to alpine-type collision belts. Here, we compare these two models of the Andes, by re-evaluating a cross-section of the range at the latitude of Santiago del Chile (33.5 °S). A particular structure, the east-vergent Aconcagua fold-and-thrust belt (AFTB), appears critical in discussing and discriminating between these two views. We revise the structural geometry of the AFTB based on satellite imagery, digital elevation models, existing geological maps and field observations. We propose a new 3D cartography and cross-section of the AFTB and conclude that the AFTB develops over a 2-3 km deep décollement, with a finite shortening of ~13 km. We integrate the AFTB to the well-documented fold and thrust belt forming the western flank of the belt and find that it is a relatively secondary feature of the Andes. From kinematic modelling using Move software (Midland Valley Ltd), we build a crustal-scale evolutionary model showing the progressive shortening of the Andean margin. We find that the AFTB can be modelled as a secondary east-verging structure, passively transported westward atop a basement ramp anticline forming the Frontal Cordillera. This evolutionary model is discussed and constrained in perspective of available thermochronology data. Our model therefore suggests that the Andes orogen can be mechanically modelled as an alpine-type collision belt, challenging our long-standing view of subduction-type mountain-belts.

  20. Mountains

    SciTech Connect

    Fuller, M.

    1989-01-01

    This book covers the following topics: Above the forest: the alpine tundra; Solar energy, water, wind and soil in mountains; Mountain weather; Mountain building and plate tectonics; Mountain walls: forming, changing, and disappearing; Living high: mountain ecosystems; Distribution of mountain plants and animals; On foot in the mountains: how to hike and backpack; Ranges and peaks of the world. Map and guidebook sources, natural history and mountain adventure trips, mountain environmental education centers and programs, and sources of information on trails for the handicapped are included.

  1. Proposed shallow drilling at the interface between the southern Oklahoma aulacogen and Ouachita fold belt, Arbuckle Mountains region, Oklahoma

    SciTech Connect

    Lidiak, E.G. . Dept. of Geology and Planetary Science); Denison, R.E.

    1993-02-01

    Two major tectonic elements in southern North America are the southern Oklahoma aulacogen and the Ouachita foldbelt. The Aulacogen is characterized by basement-cored high-angle fault blocks along which movement occurred throughout much of Paleozoic time. It is one of the most intensely deformed areas in the stable interior platform of the craton. The fold belt, in contrast, consists primarily of thin-skinned compressional structures that formed in Late Paleozoic time. These two prominent tectonic features strike at a high angle to one another and are juxtaposed in southeast Oklahoma where the contact is buried shallowly beneath Cretaceous rocks of the Gulf Coastal Plain. A drilling program comprised of a series of shallow holes drilled across the contact zone will establish the structural and stratigraphic relationships at this important tectonic interface. The results obtained should be critical in elucidating the effect that the transverse aulacogen structures had on the development of the Ouachita frontal zone. Proposed drilling sites are in northern Bryan and Choctaw counties, Oklahoma, along the Tishomingo--Belton anticlines southeast of the basement-cored eastern Arbuckle Mountains. Crystalline rocks in this region are massive middle Proterozoic granitoid rocks overlain by Cretaceous sedimentary rocks. Farther southeast, rocks in the frontal zone consist mainly of Late Paleozoic flysch-type sedimentary rocks. Depths to Paleozoic and older rocks beneath the coastal plain deposits are about 300--500 meters so that targeted structures can easily be reached.

  2. The Role of Lithospheric Delamination in the Evolution of Oroclinal Bending of Mountain Belts: Insights From Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Gogus, O. H.; Faccenna, C.; Houseman, G. A.

    2012-12-01

    In many geological settings, it has been suggested that lithospheric delamination - or any type of lithospheric removal - is associated with oroclinal bending of arcuate mountain belts, however the relationship between these two processes remain uncertain. In this work, we present a series of three-dimensional (3D) physical scaled laboratory experiments to investigate the link between these two processes. In these experiments, an idealized viscously deforming lithosphere-asthenosphere system is configured with silicone putty (representing lithospheric mantle and upper crust) and glucose syrup (representing the upper mantle and lower crust). Our primary focus was to investigate the role of the mantle flow in the physical development of oroclinal bending. Experiments without a crustal layer show that lateral mantle flow around a sinking slab is more vigorous in the center than on the lateral edges of the plate. Experiments that involve lower and upper crustal layers show a well-developed surface curvature of the upper crust when a weak lower crust permits decoupling (or delamination) of mantle lithosphere from crust and re-circulation of the mantle underneath the crust. We identified that the surface curvature of the delamination front is also dependent on the width ratio of crust to underlying mantle lithosphere layer. We present a scaling analysis of this relationship based on our experiments. Our results provide insights into the evolution of oroclinal bending/surface curvature which we relate to the collisional zones of the Mediterranean in cases where mantle lithosphere is thought to have been removed by such processes.

  3. Mapping possible subsurface granitic bodies in the northeastern Taiwan mountain belt using the VLF-EM method

    NASA Astrophysics Data System (ADS)

    Jeng, Yih; Huang, Chu-Lin; Tong, Lun-Tao; Lin, Ming-Juin; Chen, Chih-Sung; Huang, Hsin-Han

    2012-10-01

    Large gneiss bodies have been reported in the metamorphic complex in northern and eastern Taiwan for decades. Some of them are cut or intruded by granitic pegmatite dikes. However, increasing evidence suggests that the gneiss bodies are more likely to be granites or meta-granites. To validate the existence of the granites/meta-granites and propose their potential distribution in the metamorphic complex of northeastern Taiwan, a geological reconnaissance along with a crooked long-distance VLF-EM survey line of 19 km and a 4.4 km controlled experimental line were conducted in the Hoping geological area of the northeastern Taiwan mountain belt. The VLF-EM data were initially processed by using the Fraser linear filter and a nonlinear filtering method based on the ensemble empirical mode decomposition (EEMD) technique to enhance the signal and to evaluate the data quality. A skin-depth added Karous-Hjelt filter was performed to generate the equivalent current density model. With the aid of the 3-D topographic representation, the equivalent current density model clearly indicates that a vast area of granites/meta-granites in the survey area is highly possible. In spite of a large uncertainty of the pseudo-quantitative model, the geological implication of our finding agrees with the tectonic framework that Taiwan and the adjacent southern Ryukyu arc system could be part of the rifted China continental margin before the collision of the Luzon and Ryukyu arcs started in late Cenozoic.

  4. Bouguer gravity trends and crustal structure of the Palmyride Mountain belt and surrounding northern Arabian platform in Syria

    SciTech Connect

    Best, J.A.; Barazangi, M. ); Al-Saad, D.; Sawaf, T.; Gebran, A. )

    1990-12-01

    This study examines the crustal structure of the Palmyrides and the northern Arabian platform in Syria by two- and three-dimensional modeling of the Bouguer gravity anomalies. Results of the gravity modeling indicate that (1) western Syria is composed of at least two different crustal blocks, (2) the southern crustal block is penetrated by a series of crustal-scale, high-density intrusive complexes, and (3) short-wavelength gravity anomalies in the southwest part of the mountain belt are clearly related to basement structure. The crustal thickness in Syria, as modeled on the gravity profiles, is approximately 40{plus minus}4 km, which is similar to crustal thicknesses interpreted from refraction data in Jordan and Saudi Arabia. The different crustal blocks and large-scale mafic intrusions are best explained, though not uniquely, by Proterozoic convergence and suturing and early Paleozoic rifting, as interpreted in the exposed rocks of the Arabian shield. These two processes, combined with documented Mesozoic rifting and Cenozoic transpression, compose the crustal evolution of the northern Arabian platform beneath Syria.

  5. Ouachita Mountain thrust front: An integrated approach to prospect analysis in thrust belts

    SciTech Connect

    Dodge, R.L. ); Keeling, M.A. ); Cassiani, D. )

    1990-05-01

    The thrust front of the Ouachita Mountains in western Arkansas is defined by the prominent asymmetric Washburn anticline. Previously interpreted as a complexly thrust-faulted anticline, the feature has been reinterpreted as a delta or triangle structure based on integration of surface mapping from thematic mapper (TM) data with subsurface interpretation of seismic and well-log cross sections. The northern limb of the Washburn anticline consists of a relatively unfaulted steeply north-dipping sheet above a major north-dipping backthrust. The southern limb consists of several steeply south-dipping thrust sheets that form a duplex zone in the center of the delta structure. Seismic and well-log interpretations suggested the presence of the imbrication in the core of the structure, but poor seismic resolution within the structure made interpretation of the backthrust and duplex geometry difficult. Surface mapping from TM imagery indicates the presence of the backthrust and the extent and geometry of the delta structure. Thrust sheets and horses also crop out, and their geometry is a guide to interpretation of subsurface data sets. The new model of the Ouachita thrust front as a delta structure has aided in subsurface data analysis and has resulted in a better understanding of trap geometry and distribution. This study also demonstrates the application of detailed surface mapping from satellite remote-sensing data to prospect-scale analysis.

  6. Discrimination of hydrothermally altered rocks along the Battle Mountain-Eureka, Nevada, mineral belt using Landsat images

    USGS Publications Warehouse

    Krohn, M. Dennis; Abrams, Michael J.; Rowan, Lawrence C.

    1978-01-01

    Landsat Multispectral Scanner (MSS) images of the northwestern part of the Battle Mountain-Eureki, Nevada mineral belt were evaluated for distinguishing hydrothermally altered rocks associated with porphyry copper and disseminated gold deposits. Detection of altered rocks from Landsat is based on the distinctive spectral reflectance of limonite present at coatings on weathered surfaces Some altered rocks are visible as bleached areas in individual MSS bands; however, they cannot be consistently distinguished from unaltered rocks with high albedo nor from bright areas resulting .from topographic slope. Black-and-white ratio images were generated to subdue .topographic effects, and three ratio images were composited in color to portray spectral radiance differences, forming an image known as a color-ratio composite (CRC). The optimum CRC image for this area has MSS 4/5 as blue, MSS 4/6 as yellow, and MSS 6/7 as magenta, and differs in two respects from most CRC images of arid areas. First, as a result of the increased vegetation cover in the study area, MSS 5/6 was replaced by MSS 4/6 as the yellow layer. Second, 70 mm positive transparencies were replaced by large format images (64 cm), thereby improving the internal registration of the CRC image and the effective spatial resolution. The pattern of limonitic rocks depicted in the CRC closely agrees with the mapped pattern of the alteration zones at the Copper Canyon and Copper Basin porphyry copper deposits. Certain west-facing topographic slopes in the altered areas are depicted as unaltered in the CRC, apparently due to atmospheric scattering, and illustrate the need for atmospheric correction. The disseminated gold deposits at Gold Acres and Tenabo are poorly represented in the CRC because of the general absence of limonite on these deposits. The presence of unaltered limonitic sedimentary and volcanic rocks is the largest obstacle to discriminating altered areas within the mineral belt. Reflectance spectra, made

  7. Study of Magnetic Fabrics and Paleomagnetism Across Northern Transect of Taiwan Mountain Belt and Thier Implications

    NASA Astrophysics Data System (ADS)

    Yeh, E. C.; Peng, X. J.; Tseng, Y. C.; Chou, Y. M.; Lee, T. Q.; Aubourg, C.; Chen, C. C.; Lin, S. T.; Chen, C. T.

    2015-12-01

    Anisotropy of magnetic susceptibility (AMS) can be regarded as a useful tool for understanding the variation of finite strain pattern for regional deformation. In order to evaluate the interrelationship between maximum metamorphic temperature and deformation during mountain building, oriented samples of low-grade metamorphic rocks across the northern Taiwan were collected. In addition to the study of magnetic susceptibility anisotropy, experiments of natural remanent magnetization, hysteresis loop, and temperature-function magnetic susceptibility were also conducted. Results show that K1 orientation of magnetic ellipsoids suggested NW-SE compression, which is consistent with plate convergence direction. Both deformation intensity and anisotropy increase from the west to east with abnormally strong intensity and oblate strain near major faults. Magnetic fabrics have grouped six-stage from Type I to VI upon increasing strain. Study area can be divided into four domain A to D by geological characteristics and distribution of magnetic fabric. Rocks in Domain A begin to be influenced by horizontal tectonic strain. Ellipsoid is oblate and K1 is in northeast-southwest orientation, indicating NW-SW compression. Magnetic fabric belongs to Type II. K3 orientation in Domain B started to be affected by cleavage. The shape of ellipsoid is mainly oblate. Magnetic fabric is classified as Type II-III. The shape of ellipsoid in Domain C gradually converts to prolate. Distribution of K3, influenced by cleavage development, becomes a girdle in NW-SE orientation. It is treated as Type III-IV. In Domain D, though both anisotropy and deformation intensity are increased, the direction of K3 is still concentrated in vertical, not in horizontal. Results might be the reflective of discontinuous strain response to different kinematic mechanisms between the Backbone Range and the Hsueshan Range. Thermopaleogeomagnetic records of pyrrhotite remanence on both limbs of the Chungling Anticline

  8. Structural heterogeneity in mountain belts: rift- vs. subduction-related control.

    NASA Astrophysics Data System (ADS)

    Vitale Brovarone, A.; Malavieille, J.; Beltrando, M.; Beyssac, O.; Molli, G.; Herwartz, D.; Rubatto, D.; Monié, P.; Groppo, C.; Compagnoni, R.; Hermann, J.; Martin, L.; Lagabrielle, Y.; Meresse, F.

    2012-04-01

    In subduction zones, the so-called subduction channel is believed to represent the locus where the primary exhumation of deeply subducted material occurs. It is also considered as a major zone of deformation and tectonic shuffling [1, 2]. The resulting intense deformation that is commonly observed in exhumed subduction terranes is generally considered as the cause for the lithological heterogeneity (e.g. association of continental basement rocks and meta-ophiolites) encountered in highly metamorphosed units [3]. In Alpine Corsica (Western Mediteranean), metamorphism and deformation vary from very low-grade up to lawsonite-eclogite facies conditions. Compared to similar domains of Western Alps [4], deformation in Corsica is often localized, allowing a detailed characterization of primary rift-related vs. subduction-related structures to be done through a wide spectrum of metamorphic conditions [4]. Based on extensive stratigraphic, structural, petrologic (including RSCM and pseudosection) and geochronological (U-Pb zircon; Lu-Hf garnet and lawsonite; Ar-Ar phengite) data, the main tectono-metamorphic units and their evolution from rifting to the final stages of orogenesis have been established. They show a high lithological heterogeneity that is essentially related to primary stratigraphic/tectonic processes occurring prior to subduction during continental break-up and subsequent oceanic extensional tectonics. Otherwise, each unit shows a remarkable metamorphic homogeneity over large areas. These features indicate that large volumes of subducted lithosphere behave as single and coherent tectonostratigraphic units during subduction/exhumation. As a consequence, the number of significant tectono-metamorphic boundaries is limited to the main contacts separating these large volumes of former lithosphere. Our study highlights on the major control exerted by inherited extensional structures during subduction and mountain building in opposition to the formation subduction

  9. An oxygen isotope and geochemical study of meteoric-hydrothermal systems at Pilot Mountain and selected other localities, Carolina slate belt

    USGS Publications Warehouse

    Klein, T.L.; Criss, R.E.

    1988-01-01

    Several epigenetic mineral deposits in the Carolina slate belt are intimately related to meteoric-hydrothermal systems of late Precambrian and early Paleozoic age. At Pilot Mountain, low 18O rocks correlate well with zones of strong silicic alteration and alkali leaching accompanied by high alumina minerals (sericite, pyrophyllite, andalusite ?? topaz) and anomalous concentrations of Cu, Mo, Sn, B, and Au. A magmatic source for much of the sulfur and metal is likely, and a subordinate magmatic water component in the fluid of the central zone is possible. This central zone is surrounded by a >30 km2 peripheral zone of low 18O sericite schists, chlorite-sericite schists, and andesitic volcanic rocks. Reconnaissance studies of other alteration zones in the Carolina slate belt have so far disclosed the involvement of meteoric-hydrothermal fluids at the Snow Camp pyrophyllite deposit, at the Hoover Hill and Sawyer Au mines, and probably at the Haile and Brewer Au mines. -from Authors

  10. Spatial and temporal dynamics of sediment in contrasted mountainous watersheds (Mexican transvolcanic belt and French Southern Alps) combining river gauging, elemental geochemistry and fallout radionuclides

    NASA Astrophysics Data System (ADS)

    Evrard, O.; Navratil, O.; Gratiot, N.; Némery, J.; Duvert, C.; Ayrault, S.; Lefèvre, I.; Legout, C.; Bonté, P.; Esteves, M.

    2009-12-01

    In mountainous environments, an excessive fine sediment supply to the rivers typically leads to an increase in water turbidity, contaminant transport and a rapid filling of reservoirs. This situation is particularly problematic in regions where water reservoirs are used to provide drinking water to large cities (e.g. in central Mexico) or where stream water is used to run hydroelectric power plants (e.g. in the French Southern Alps). In such areas, sediment source areas first need to be delineated and sediment fluxes between hillslopes and the river system must be better understood before implementing efficient erosion control measures. In this context, the STREAMS (« Sediment Transport and Erosion Across MountainS ») project funded by the French National Research Agency (ANR) aims at understanding the spatial and temporal dynamics of sediment at the scale of mountainous watersheds (between 500 - 1000 km2) located in contrasted environments. This 3-years study is carried out simultaneously in a volcanic watershed located in the Mexican transvolcanic belt undergoing a subhumid tropical climate, as well as in a sedimentary watershed of the French Southern Alps undergoing a transitional climate with Mediterranean and continental influences. One of the main specificities of this project consists in combining traditional monitoring techniques (i.e. installation of river gauges, turbidimeters and sediment samplers in several sub-catchments) and sediment fingerprinting using elemental geochemistry (measured by Instrumental Neutron Activation Analysis - INAA - and Inductively Coupled Plasma - Mass Spectrometry - ICP-MS) and fallout radionuclides (measured by gamma spectrometry). In the French watershed, geochemical analysis allows outlining different sediment sources (e.g. the contribution of calcareous vs. marl-covered sub-watersheds). Radionuclide ratios (e.g.Be-7/Cs-137) allow identifying the dominant erosion processes occurring within the watershed. Areas mostly

  11. Mountain Biking with Groups: A "Safe" Activity?

    ERIC Educational Resources Information Center

    Allen, Terry

    2001-01-01

    A survey mailed to 200 British mountain bike leaders found that rates of cycling accidents and injuries were greater in forests and woodlands than on terrain where a license is required to lead groups of young cyclists. Excessive speed was mentioned in most accidents, coupled with poor use of breaks in many cases. (SV)

  12. Long-Period Ground Motion in the Arabian Gulf from Earthquakes in the Zagros Mountains Thrust Belt

    NASA Astrophysics Data System (ADS)

    Pitarka, Arben; Al-Amri, Abdullah; Pasyanos, Michael E.; Rodgers, Arthur J.; Mellors, Robert J.

    2015-10-01

    The Arabian Gulf is adjacent to the Zagros Mountains, one of the most seismically active regions in the world. We observe that broadband seismic records of Zagros earthquakes recorded on the Arabian side of the Gulf display long-duration surface waves. While shorter periods (<1 s) are attenuated from crossing the deep sediments (>10 km) of the Gulf basin, the long-period energy is enhanced and transmitted efficiently. Consequently, large earthquakes in the Zagros could result in amplified ground motions at long periods (2-10 s) relative to average behavior. Such ground motions are of concern for large engineered structures, such as tall buildings and long bridges with resonant periods in the same period range. Here we present results of investigations of the characteristics of ground motions recorded on the western shore of the Gulf from selected earthquakes in the Zagros Mountains region. Exceptionally, long-duration seismic waves, as compared with standard models, are shown to occur with periods of 2-10 s. This may be due to waveguide effects in the deep sedimentary basin structure of the Arabian Platform. In addition to analyzing recorded ground motion we performed 3D wave propagation simulations using a finite difference method and experimental velocity models of the Gulf, with different shallow sedimentary layers structures. The simulation results confirm our hypothesis that long-period waves with extremely long duration and relatively large amplitudes are caused by the geometry of the basin sedimentary layers and, to some extent, by shallow earthquake depths. Combined effects of basin edge geometry with sharp velocity contrasts and shallow sources (<10 km) on the eastern side of the Arabian Gulf can cause large long-period ground motion on the western side of the Gulf. In contrast, the short-period content of ground motion (<2 s) at long distances is relatively weak. This is mainly due to wave propagation scattering and attenuation in the shallow sedimentary

  13. Evidence for synchronous thin-skinned and basement deformation in the Cordilleran fold-thrust belt: the Tendoy Mountains, southwestern Montana

    NASA Astrophysics Data System (ADS)

    McDowell, Robin John

    1997-01-01

    The Tendoy Mountains contain the easternmost thin-skinned thrust sheets in the Cordilleran fold-thrust belt of southwestern Montana, and are in the zone of tectonic overlap between the Rocky Mountain foreland and the Cordilleran fold-thrust belt. The three frontal thrust sheets of the Tendoy Mountains are from north to south, the Armstead, McKenzie, and Tendoy sheets. Near the southeastern terminus of the Tendoy thrust sheet is a lateral ramp in which the Tendoy thrust climbs along strike from the Upper Mississippian Lombard Limestone to lower Cretaceous rocks. This ramp coincides with the southeastern side of the Paleozoic Snowcrest trough and projection of the range-flanking basement thrust of the Blacktail-Snowcrest uplift, suggesting either basement or stratigraphic control on location of the lateral ramp. Axes of major folds on the southern part of the Tendoy thrust sheet are parallel to the direction of thrust transport and to the trend of the Snowcrest Range. They are a result of: (1) Pre-thrust folding above basement faults; (2) Passive transportation of the folds from a down-plunge position; (3) Minor reactivation of basement faults; and (4) Emplacement of blind, sub-Tendoy, thin-skinned thrust faults. The Tendoy sheet also contains a major out-of-sequence thrust fault that formed in thick Upper Mississippian shales and created large, overturned, foreland-verging folds in Upper Mississippian to Triassic rocks. The out-of-sequence fault can be identified where stratigraphic section is omitted, and by a stratigraphic separation diagram that shows it cutting down section in the direction of transport. The prominent lateral ramp at the southern terminus of the Tendoy thrust sheet is a result of fault propagation through strata folded over the edge of the Blacktail-Snowcrest uplift.

  14. Relief Evolution in Tectonically Active Mountain Ranges

    NASA Technical Reports Server (NTRS)

    Whipple, Kelin X.

    2004-01-01

    The overall aims of this 3-yr project, as originally proposed were to: (1) investigate quantitatively the roles of fluvial and glacial erosion in the evolution of relief in mountainous regions, and (2) test rigorously the quality and accuracy of SRTM topographic data in areas of rugged relief - both the most challenging and of greatest interest to geomorphic, neotectonic, and hazards applications. Natural laboratories in both the western US and the Southern Alps of New Zealand were identified as most promising. The project has been both successful and productive, despite the fact that no SRTM data for our primary field sites in New Zealand were released on the time frame of the work effort. Given the delayed release of SRTM data, we pursued the scientific questions of the roles of fluvial and, especially, glacial erosion in the evolution of relief in mountainous regions using available digital elevation models (DEMs) for the Southern Alps of New Zealand (available at both 25m and 50m pixel sizes), and USGS 10m and 30m DEMs within the Western US. As emphasized in the original proposal, we chose the emphasis on the role of glacial modification of topographic relief because there has been little quantitative investigation of glacial erosion processes at landscape scale. This is particularly surprising considering the dramatic sculpting of most mid- and high-latitude mountain ranges, the prodigious quantities of glacially-derived sediment in terrestrial and marine basins, and the current cross-disciplinary interest in the role of denudational processes in orogenesis and the evolution of topography in general. Moreover, the evolution of glaciated landscapes is not only a fundamental problem in geomorphology in its own right, but also is at the heart of the debate over Late Cenozoic linkages between climate and tectonics.

  15. Climatic belt dynamics on a tropical mountain under strong anthropogenic and zoogenic impact: Mt Tsebet (3946 m a.s.l.) in East Africa

    NASA Astrophysics Data System (ADS)

    Nyssen, Jan; Frankl, Amaury; Gebrehiwot, Kindeya; Yirga, Gidey; Guyassa, Etafa; de Mûelenaere, Stephanie; Poesen, Jean; Hemp, Andreas; Haile, Mitiku

    2010-05-01

    The links between decreasing size and volume of the glaciers in East Africa's tropical mountains and the position of climatic belts on the one hand and global warming on the other have led to various interpretations on the occurrence of global warming and its magnitude and impacts in this part of the world. Here, we investigate the existence of temperature changes in East Africa and their impacts in high mountain regions by analyzing the position of climatically determined vegetation belts on Mt. Tsebet (12°52'N, 39°30'E, 3946 m a.s.l.) in northern Ethiopia between 1986 and 2010. This 27 km² massif, which was first surveyed and photographed in 1868, was chosen as a study area because, unlike Simien Mountains or Bale Mts. (Ethiopia), the antropogenic and zoogenic impact on the environment has not been reduced through time. By choosing Tsebet, we avoided areas that have become recently protected (such as the above-mentioned national parks); there, trees that newly grow more upslope might be ascribed to the protected status. In protected areas, the position of upper cropland limits may be controlled by regulations that prevent farmers from expanding farmlands upslope, even if climatic and topographic conditions would allow doing so. On Tsebet, where direct human and zoogenic impact exists up to the highest elevations, we will establish the position of two temperature-linked vegetation limits (i.e. Erica arborea and Hordeum vulgare or barley) in 1986, 1994 and 2010, through fieldwork (February 2010) and aerial photo interpretation. Changes in population density in the villages around Mt. Tsebet will be analysed through house counting on aerial photographs. The fieldwork will include a stay in mountain villages, during which interviews will be done on dates and reasons for shifting of the cultivation limit. The results will be analysed through geostatistical methods and will provide a better understanding of the magnitude of air temperature and possibly precipitation

  16. Vernal Point and Seismic Activity in Tibet Mountains and Andes Mountains

    NASA Astrophysics Data System (ADS)

    Chavez-Sumarriva, Israel; Chavez-Campos, Teodosio; Chavez S, Nadia

    2014-05-01

    The gravitational influence of the sun and moon on the equatorial bulges of the mantle of the rotating earth causes the precession of the earth. The retrograde motion of the vernal point through the zodiacal band is 26,000 years and passes through each constellation in an average of 2000 years (Milankovitch subcycle). The vernal point retrogrades one precessional degree approximately in 72 years (Gleissberg-cycle), and approximately enters into the Aquarius constellation (declination 11.5° S) on March 20, 1940. On earth this entry was verify through: a) stability of the magnetic equator in the south central zone of Peru and in the north zone of Bolivia (11.5º South latitude) since 1940 b) the greater intensity of equatorial electrojet (EEJ) in Peru and Bolivia since 1940. Besides, there was a long history of studies of coupling between earthquake-ionosphere. In IUGG (Italy-2007), Cusco was proposed as a prime meridian that was based on: (1) the new prime meridian (72º W == 0º) was parallel to the Andes and its projection the meridian (108° E == 180º) intersects the Tibetan plate (Asia). (2) On earth these two areas present the greatest thickness of the crust with an average depth of 70 kilometers. The aim was to synchronize the earth sciences phenomena (e.g. geology, geophysics, etc.). The coordinate system had the vernal point from meridian (72º W== 0º) and March 20, 1940. The retrograde movement of the vernal point was the first precessional degree (2012 = 1940 + 72). The west coast of South America (parallel to meridian 72º W== 0º) was a segment of the circum-pacific seismic belt where more than two thirds of major earthquakes in the world happened. During the first precessional degree (1940 +72 ==2012) seismic activity were: (a) near the new prime meridian (72° W == 0°) occurs in: (a1) Haiti (18.4° N, 72.5° W), January 12, 2010 with magnitude of 7.0 Mw. (a2) Chile (36.28° S, 73.23° W), February 27, 2010 with Magnitude of 8.8 Mw. (a3) Chile (35

  17. A comparison of species composition and community assemblage of secondary forests between the birch and pine-oak belts in the mid-altitude zone of the Qinling Mountains, China

    PubMed Central

    Chai, Zongzheng

    2016-01-01

    The mid-altitude zone of the Qinling Mountains in China was once dominated by birch and pine-oak belts but are now mainly covered by secondary growth following large-scale deforestation. Assessing the recovery and sustainability of these forests is essential for their management and restoration. We investigated and compared the tree species composition and community assemblages of secondary forests of the birch and pine-oak belts in the Huoditang forest region of the Qinling Mountains after identical natural recoveries. Both types of belts had rich species compositions and similar floristic components but clearly different community structures. Tree diversity was significantly higher for the birch than the pine-oak belt. Niche and neutral processes simultaneously influenced the species distribution and community dynamics of the belts, and these forests were able to maintain stable development during natural recoveries. The conservation and management of these forests should receive more attention to protect biodiversity and the forest resources in the Qinling Mountains. PMID:27123377

  18. Climate dominated topography in a tectonically active mountain range

    NASA Astrophysics Data System (ADS)

    Adams, B. A.; Ehlers, T. A.

    2015-12-01

    Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The broad spatial trend in channel steepness values suggests that the locus of high rock uplift rates is coincident with the rugged range core, in a similar position as high temperature and pressure lithologies, but not in the low lying foothills as has been previously suggested by low-temperature thermochronometry. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns. We demonstrate the same topographic effects are recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on topography makes the argument of mountain range steadiness untenable in significantly glaciated settings. Furthermore, our results suggest that most glaciated Cenozoic ranges are likely still in a mode of readjustment as fluvial systems change topography and erosion rates to equilibrate with rock uplift rates.

  19. Style and magnitude of Mesozoic thrust faulting in the hinterland of the Sevier thrust belt Pequop Mountains-Wood Hills-East Humboldt Range region, northeast Nevada

    SciTech Connect

    Camilleri, P.A. . Dept. of Geology and Geophysics)

    1993-04-01

    The Pequop Mountains (PM), Wood Hills (WH) and East Humboldt Range (EHR), NE Nevada, provide evidence that the hinterland of the Sevier thrust belt experienced large-magnitude Mesozoic shortening ([>=]55 km) and crustal thickening ([>=] 30 km). These ranges expose a structurally continuous crustal cross section of unmetamorphosed to high pressure upper amphibolite facies Triassic to Precambrian miogeoclinal strata. This sequence lies structurally beneath unmetamorphosed extensional klippen that omit metamorphic grade and crustal section, but also repeat stratigraphic units. Because they repeat stratigraphic units, the underlying miogeoclinal section, or footwall, must have once lain beneath a thrust fault (herein named the Windermere thrust). The footwall of the Windermere thrust was exhumed by two generations of top-to-the-W-NW low-angle normal faults that are distinguished by whether they are depositionally overlapped by Eocene volcanic rocks or if they cut the volcanic rocks in their hanging walls. The latter phase is associated with development of the mid-Tertiary extensional mylonitic shear zone in the EHR. An integration of geobarometric, metamorphic, and map data suggest (1) a NW dip of the footwall of the Windermere thrust with metamorphic facies belts trending perpendicular to dip direction and metamorphic grade increasing down dip, and (2) a top-to-the-SE sense-of-slip for the Windermere thrust. Assuming that the Windermere thrust comprised a flat on the youngest rocks exposed in the footwall (Triassic), the Mesozoic depth to the Windermere thrust in the northern PM is [>=] 7 km, in WH is [approximately]10--16 km, and in the EHR[>=]30 km. The Windermere thrust accommodated a minimum of 50 km of shortening associated with the Independence thrust is [>=] 5 km. These data indicate that the amount of hinterland shortening in NE Nevada greatly exceeds that to the south in the Eureka belt.

  20. Proton Radiation Belt Dynamics in Low Earth Orbits Interrelated with Solar Activity

    NASA Astrophysics Data System (ADS)

    Malakhov, Vitaly; Aleksandrin, Sergey; Mikhailov, Vladimir; Bakaldin, Alexey; Mayorov, Andrey; Mayorova, Marina; Koldashov, Sergey; Sharonova, Nadezhda; Galper, Arkady; Zharaspaev, Temir; Batischev, Alexey

    Existing empirical radiation belt models do not able to calculate trapped particle fluxes with taking into account changing solar activity. Widely using AP-8 model allows to evaluate proton fluxes just in two cases: for minimum or maximum of a solar cycle. New AP-9 model is under developing. Also new additional possibilities for experimental study of radiation belt dynamics is opened up. Since 2006 year PAMELA and ARINA experiments onboard satelite RESURS-DK1 are carried out. PAMELA is in the first place spectrometer to study antiparticles in cosmic rays. The ARINA instrument is intended studying high-energy charged particle bursts in the magnetosphere. Along with such fundamental goals these instruments give opportunity to carry out measurements of trapped particles in the inner radiation belt. Complex of two mentioned instruments covers proton energy range from 30 MeV up to energy limit for trapping (~2 GeV). Continuous measurements with PAMELA and ARINA include falling and rising phases of 23/24 solar cycles. In this report we present temporal profile of proton fluxes in the inner zone of the radiation belt (1.11activity (sunspot number) was revealed. At that it was shown that proton fluxes of energies >30MeV at the solar minimum several times greater than at the solar maximum.

  1. tEffect of the brittle-ductile transition on the topography of compressive mountain belts on Earth and Venus

    NASA Astrophysics Data System (ADS)

    Williams, Charles A.; Connors, Chris; Dahlan, F. A.; Price, Evelyn J.; Suppe, John

    1994-10-01

    The Coulomb critical taper model has been very successful in explaining the large-scale topography of a number of terrestrial accretionary wedges; however, this model is limited to cases of purely brittle-frictional deformation. In this paper we extend te range of applicability of the critical taper model by explicity including the effects of temperature-dependent ductile deformation. The new model includes temperature-dependent power law flow, an assumed velocity field, and linear thermal gradients in the atmosphere and within the crust. Flexural isostasy is also incorporated so that the decollement geometry is computed as a response to the applied load of the wedge material. We assume that ductile deformation within the wedge itself is controlled primarily by duffusin flow, whereas ductile deformation within the wedge itself is controlled by dislocation creep. We have applied the model to two fold-and-thrust belts on Venus (Maxwell Montes and Uorsar Rypes) and to the Andes on Earth, and we find good agreement between observed and predicted topography using reasonable parameter values. The model accounts for the observed positive correlation between relief and elevation of Venusian fold-and-thrust belts on the basis of different thermal environments at different elevations. It is also able to explain the first-order difference between terrestrial and Venusian fold-and-thrust belts; fundamentally, this difference is due to a combination of the lower temperatures and the presence of water on Earth.

  2. Glacial reorganization of topography in a tectonically active mountain range

    NASA Astrophysics Data System (ADS)

    Adams, Byron; Ehlers, Todd

    2016-04-01

    Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns, and not tectonic rock uplift rates. Alpine glaciers drastically altered the relief structure of the Olympic Mountains. The details of these relief changes are recorded in channel profiles as overdeepenings, reduced slopes, and associated knickpoints. We find the position of these relief changes within the orogen is dependent on the position of the Pleistocene ELA. While alpine glaciers overdeepened valleys in regions near the Pleistocene ELA (which has a tendency to increase relief), headward erosion of west and north flowing glacier systems captured significant area from opposing systems and caused drainage divide lowering. This divide lowering reduced relief throughout the range. We demonstrate similar topographic effects recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on

  3. Late Quaternary tectonic activity and crustal shortening rate of the Bogda mountain area, eastern Tian Shan, China

    NASA Astrophysics Data System (ADS)

    Wu, Chuanyong; Wu, Guodong; Shen, Jun; Dai, Xunye; Chen, Jianbo; Song, Heping

    2016-04-01

    The Bogda mountain range is the highest range among the northern Tian Shan mountains. Based on geologic and geomorphologic field surveys, trench excavation and optically stimulated luminescence (OSL) dating, we targeted the active Fukang fault along the Bogda mountain range and identified the late Quaternary deformation characteristics of this area. We found that the Fukang fault dislocated different geomorphic surfaces of the northern Bogda piedmont. The vertical fault displacement corresponds to the topographic relief of the Bogda over long time scales. Since the late Quaternary, the crustal shortening rate was estimated to be 0.90 ± 0.20 mm/yr, which is less than that of the western segment of the northern Tian Shan. We interpret the Bogda fold and thrust belt to be a thick-skinned structure, since a high angle thrust fault bounds the Bogda mountain range and the foreland basin. The deformation characteristics of this region have been dominated by vertical uplift, and the component of propagation toward the basin has been very limited. This tectonic deformation is evidenced as vertical growth. Although the deformation rate is small, the uplift amplitude is very significant in this region.

  4. Regional Observation of Seismic Activity in Baekdu Mountain

    NASA Astrophysics Data System (ADS)

    Kim, Geunyoung; Che, Il-Young; Shin, Jin-Soo; Chi, Heon-Cheol

    2015-04-01

    Seismic unrest in Baekdu Mountain area between North Korea and Northeast China region has called attention to geological research community in Northeast Asia due to her historical and cultural importance. Seismic bulletin shows level of seismic activity in the area is higher than that of Jilin Province of Northeast China. Local volcanic observation shows a symptom of magmatic unrest in period between 2002 and 2006. Regional seismic data have been used to analyze seismic activity of the area. The seismic activity could be differentiated from other seismic phenomena in the region by the analysis.

  5. Sediment yield along the Andes: continental budget, regional variations, and comparisons with other basins from orogenic mountain belts

    NASA Astrophysics Data System (ADS)

    Latrubesse, Edgardo M.; Restrepo, Juan D.

    2014-07-01

    We assess the sediment yield at 119 gauging stations distributed from Colombia to Patagonia, covering the different morphotectonic and morphoclimatic settings of the Andes. The most productive areas are the Meta River basin within the northern Andes and the Bolivian and northern Argentina-Chaco systems, which produce an average of 3345, 4909 and 2654 t km2 y- 1 of sediment, respectively. The rivers of the northern and central Andes (excluding the Pacific watersheds of Peru, northern Chile, and central Argentina) have a weighted mean sediment yield of 2045 t km- 2 y- 1 and produce 2.25 GTy- 1 of total sediment. A major constraint estimating the Andean continental budget of sediment yield lies in the lack of gauging data for the Peruvian region. Using the available gauge stations, the regional sediment yield appears underestimated. Assuming a higher value of sediment yield for the Peruvian Andes, the total budget for the whole central Andes could range between 2.57 GT y- 1 and 3.44 GT y- 1. A minimum of ~ 0.55 GT y- 1 and a probable maximum of ~ 1.74 GT y- 1 of sediment are deposited in the intramontane and surrounding proximal sedimentary basins. The magnitude of sediment yield in the Andes is comparable to other rivers draining orogenic belts around the world.

  6. Pelvic Belt Effects on Pelvic Morphometry, Muscle Activity and Body Balance in Patients with Sacroiliac Joint Dysfunction

    PubMed Central

    Soisson, Odette; Lube, Juliane; Germano, Andresa; Hammer, Karl-Heinz; Josten, Christoph; Sichting, Freddy; Winkler, Dirk; Milani, Thomas L.; Hammer, Niels

    2015-01-01

    Introduction The sacroiliac joint (SIJ) is frequently involved in low back and pelvic girdle pain. However, morphometrical and functional characteristics related to SIJ pain are poorly defined. Pelvic belts represent one treatment option, but evidence still lacks as to their pain-reducing effects and the mechanisms involved. Addressing these two issues, this case-controlled study compares morphometric, functional and clinical data in SIJ patients and healthy controls and evaluates the effects of short-term pelvic belt application. Methods Morphometric and functional data pertaining to pelvic belt effects were compared in 17 SIJ patients and 17 controls. Lumbar spine and pelvis morphometries were obtained from 3T magnetic resonance imaging. Functional electromyography data of pelvis and leg muscles and center of pressure excursions were measured in one-leg stance. The numerical rating scale was used to evaluate immediate pain-reducing effects. Results Pelvic morphometry was largely unaltered in SIJ patients and also by pelvic belt application. The angle of lumbar lateral flexion was significantly larger in SIJ patients without belt application. Muscle activity and center of pressure were unaffected by SIJ pain or by belt application in one-leg stance. Nine of 17 patients reported decreased pain intensities under moderate belt application, four reported no change and four reported increased pain intensity. For the entire population investigated here, this qualitative description was not confirmed on a statistical significant level. Discussion Minute changes were observed in the alignment of the lumbar spine in the frontal plane in SIJ patients. The potential pain-decreasing effects of pelvic belts could not be attributed to altered muscle activity, pelvic morphometry or body balance in a static short-term application. Long-term belt effects will therefore be of prospective interest. PMID:25781325

  7. An Early Cretaceous garnet pressure-temperature path recording synconvergent burial and exhumation from the hinterland of the Sevier orogenic belt, Albion Mountains, Idaho

    NASA Astrophysics Data System (ADS)

    Kelly, Eric D.; Hoisch, Thomas D.; Wells, Michael L.; Vervoort, Jeffrey D.; Beyene, Mengesha A.

    2015-08-01

    Rocks may undergo complex pressure-temperature ( P- T) histories during orogenesis in response to alternating episodes of synconvergent burial and exhumation. In this study, chemical zoning in garnets combined with textural and chemical evidence from the schist of Willow Creek in the Albion Mountains of south-central Idaho (USA), reveals a complex P- T path during the early stages of Sevier orogenesis. The distribution of quartz inclusions combined with internal resorption features establishes a hiatus in garnet growth. Chemical zoning was simulated using a G-minimization approach to yield a P- T path consisting of three distinct pressure changes during increasing temperature, defining an "N" shape. Lu-Hf isochron ages from multiple garnet fractions and whole-rock analyses in two samples are 132.1 ± 2.4 and 138.7 ± 3.5 Ma. The samples were collected from the hanging wall of the Basin-Elba thrust fault and yielded results similar to those previously obtained from the footwall. This leads to several conclusions: (1) Both the hanging wall and footwall experienced the same metamorphic event, (2) the paths document a previously unrecognized crustal thickening and synorogenic extension cycle that fills an important time gap in the shortening history of the Sevier retroarc, suggesting progressive eastward growth of the orogen rather than a two-stage history, and (3) episodes of extensional exhumation during protracted convergent orogenesis are increasingly well recognized and highlight the dynamic behavior of orogenic belts.

  8. Geomorphic assessment of the tectonic activity of Qiulitagh fold-belt, Kuqa foreland basin, Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Saint Carlier, Dimitri; Graveleau, Fabien; Delcaillau, Bernard; Hurtrez, Jean-Emmanuel; Vendeville, Bruno

    2014-05-01

    The Qiulitagh fold belt is an anticline structure located in the Kuqa fold-and-thrust belt (southern Tian Shan, China), whose active folding is well documented by structural and palaeomagnetic studies (Chen et al., 2007; Hubert-Ferrari et al., 2007; Li et al., 2012; Wang et al., 2011). The topography of Quilitagh fold belt can be divided into two SW-NE parallel ridges: 1) a 90 km long northern ridge, composed of the Northern Qiulitagh anticline and the Yakelike anticline, and 2) a 165km long southern ridge, composed of the Southern Qiulitagh anticline and the Mishikantage anticline. Due to the current absence of vegetation and relative homogeneity of outcropping lithologies (mainly Neogene detrital sandstone and silstone), these anticlines provide exceptional field cases for investigating the dynamic relationships between fold growth mechanisms, the subsurface structures, the geomorphic entities and the drainage network evolution. We used free topographic and satellite image datasets to carry out a morphometric study of the Quilitagh fold-belt and investigate the kinematics of active folding. Topographic datasets include Digital Elevation Models (DEM) from the NASA SRTM V.4.0 and ASTER programs, whereas satellite images are extracted from Landsat 7 shots and Google Earth. These datasets were incorporated in GIS software where three scales of observation were investigated: 1) a global fold scale, 2) a drainage basin scale and 3) a valley scale. At the drainage basin scale, we selected about 250 items and quantified several geomorphic indices of relative active tectonic growth. These are the basin mean slope, hypsometric integral, basin asymmetry and local relief. We also used published seismic profiles to link the 3D subsurface geometry of the salt-related Qiulitagh fold belt with the geomorphic signal. Results indicate that the morphometry of Quilitagh drainage basins (hypsometry, drainage basin asymmetry, local relief, valley incision, steepness index) change

  9. Holocene glacier activity in the British Columbia Coast Mountains, Canada

    NASA Astrophysics Data System (ADS)

    Mood, Bryan J.; Smith, Dan J.

    2015-11-01

    The Coast Mountains flank the Pacific Ocean in western British Columbia, Canada. Subdivided into the southern Pacific Ranges, central Kitimat Ranges and northern Boundary Ranges, the majority of large glaciers and icefields are located in the Boundary and Pacific ranges. Prior descriptions of the Holocene glacial history of this region indicate the Holocene was characterized by repeated episodes of ice expansion and retreat. Recent site-specific investigations augment our understanding of the regional character and duration of these events. In this paper, previously reported and new radiocarbon evidence is integrated to provide an updated regional assessment. The earliest evidence of glacier expansion in the Coast Mountains comes from the Boundary Ranges at 8.9 and 7.8 ka and in the Pacific Ranges at 8.5-8.2 ka, with the latter advance corresponding to an interval of rapid, global climate deterioration. Although generally warm and dry climates from 7.3 to 5.3 ka likely limited the size of glaciers in the region, there is radiocarbon evidence for advances over the interval from 7.3 to 6.0 and at 5.4-5.3 ka in the Pacific Ranges. Following these advances, glaciers in the Pacific Ranges expanded down valley at 4.8-4.6, 4.4-4.0, 3.5-2.6, 1.4-1.2, and 0.8-0.4 ka, while glaciers in Boundary Ranges were advancing at 4.1-4.0, 3.7-3.4, 3.1-2.8, 2.3, 1.7-1.1, and 0.8-0.4 ka. After 0.4 ka, it appears that most glaciers in the Coast Mountains continued to expand to attain their maximum Holocene extents by the early 18th to late 19th centuries. This enhanced record of Holocene glacier activity highlights the temporal synchrony in the Coast Mountains. Individual expansion events in the mid-to late Holocene broadly correspond to intervals of regional glacier activity reported in the Canadian Rocky Mountains, in Alaska, and on high-elevation volcanic peaks in Washington State.

  10. Potential Future Igneous Activity at Yucca Mountain, Nevada

    SciTech Connect

    M. Cline; F. Perry; G. Valentine; E. Smistad

    2005-05-26

    Location, timing, and volumes of post-Miocene volcanic activity, along with expert judgment, provide the basis for assessing the probability of future volcanism intersecting a proposed repository for nuclear waste at Yucca Mountain, Nevada. Analog studies of eruptive centers in the region that may represent the style and extent of possible future igneous activity at Yucca Mountain have aided in defining the consequence scenarios for intrusion into and eruption through a proposed repository. Modeling of magmatic processes related to magma/proposed repository interactions has been used to assess the potential consequences of a future igneous event through a proposed repository at Yucca Mountain. Results of work to date indicate future igneous activity in the Yucca Mountain region has a very low probability of intersecting the proposed repository. Probability of a future event intersecting a proposed repository at Yucca Mountain is approximately 1.7 x 10{sup -8} per year. Since completion of the Probabilistic Volcanic Hazard Assessment (PVHA) in 1996, anomalies representing potential buried volcanic centers have been identified from aeromagnetic surveys. A re-assessment of the hazard is currently underway to evaluate the probability of intersection in light of new information and to estimate the probability of one or more volcanic conduits located in the proposed repository along a dike that intersects the proposed repository. US Nuclear Regulatory Commission regulations for siting and licensing a proposed repository require that the consequences of a disruptive event (igneous event) with annual probability greater than 1 x 10{sup -8} be evaluated. Two consequence scenarios are considered: (1) igneous intrusion-poundwater transport case and (2) volcanic eruptive case. These scenarios equate to a dike or dike swarm intersecting repository drifts containing waste packages, formation of a conduit leading to a volcanic eruption through the repository that carries the

  11. The Consequences of Uniform High Temperatures in the Cordillera and Other Subduction Backarc Mountain Belts Compared to Cratons

    NASA Astrophysics Data System (ADS)

    Hyndman, R. D.

    2012-12-01

    Many if not most continental areas have experienced a period of being in the subduction zone backarc. The thermal regime of the Cordillera and other current and recent subduction backarcs is concluded to be remarkably uniformly hot, 800-900C at Moho, in contrast to cratons, 400-500C at Moho. Constraints come from: heat flow-heat generation models; mantle tomography velocities; xenolith pressure (depth)-temperatures, Te (effective elastic lithosphere thickness); seismic and electrical thickness of lithosphere; maximum depth of seismicity; depth of Curie temperature; and thermal elevation. The consequences of these high temperatures are reviewed: (1) In the Cordillera there is a surprisingly constant 1,600 m elevation contribution due to thermal isostasy compared to the cratons. The thermal expansion contribution results in the Cordillera having a high elevation in spite of having an average thin crust (~35 km), compared to the cratons (~40 km). (2) Weak mobile belts like the Cordillera are a consequence of their high temperatures. Plate boundary forces and elevation potential are sufficient for ongoing lithosphere deformation. Cratons are cold and strong. (3) In the Cordillera and most other back arcs, the lower crust is very weak and commonly acts as a detachment over long distances. Lower crust horizontal reflectors may mark the detachment. Also, foreland basal thrusting often detaches into the backarc lower crust. (4) In backarcs, high metamorphic temperature gradients (e.g., Barrovian metamorphism) predate collision orogeny; there is no "heat of orogeny" required. (5) Cordillera earthquakes occur only in the brittle upper crust, 10-15 km. When subduction terminates, backarcs cool with a time constant of about 300 m.y. and approach a cold craton thermal regime by ~1 Ga. As an example, the former Appalachian backarc has now substantially cooled.

  12. Discrimination of hydrothermally altered rocks along the Battle Mountain-Eureka, Nevada mineral belt using LANDSAT images

    NASA Technical Reports Server (NTRS)

    Krohn, M. D.; Abrams, M. J.; Rowan, L. C. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. Limonitic alteration halos associated with two copper prophyry deposits were successfully mapped at Battle Mountain. Alteration halos from both a hypogene system at Copper Canyon and a supergene system at Copper Basin are recognizable in the composite. Both copper porphyry deposits are located in sedimentary rock units that commonly have ferruginous coatings; yet, in most cases, the hydrothermally derived limonite was distinguishable in the CRC from sedimentary limonite. Large format playback images with pixel sizes from 200 to 400 micron m provided details of spatial resolution and color separation unachievable on enlargements from 70 mm film chips. Details of the alteration halos could be resolved only in the large format images. Two aspects of the alteration halos of the porphyry copper deposits were not mapped on the CRC. The optimum CRC image for the area studied consists of MSS 4/5 as blue, MSS 4/6 as yellow, and MSS 6/7 as magenta using diazo films. The disseminated gold deposits at Gold Acres are not depicted in the CRC image.

  13. Factors limiting microbial activity in volcanic tuff at Yucca Mountain

    SciTech Connect

    Kieft, T.L.; Kovacik, W.P.; Taylor, J.

    1996-09-01

    Samples of tuff aseptically collected from 10 locations in the Exploratory Shaft Facility at the site of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada Test Site were analyzed for microbiological populations, activities, and factors limiting microbial activity. Radiotracer assays ({sup 14}C-labeled organic substrate mineralization), direct microscopic counts, and plate counts were used. Radiolabeled substrates were glucose, acetate, and glutamate. Radiotracer experiments were carried out with and without moisture and inorganic nutrient amendments to determine factors limiting to microbial activities. Nearly all samples showed the presence of microorganisms with the potential to mineralize organic substrates. Addition of inorganic nutrients stimulated activities in a small number of samples. The presence of viable microbial communities within the tuff has implications for transport of contaminants.

  14. CHARACTERIZATION OF ACTIVE MAIN BELT OBJECT P/2012 F5 (GIBBS): A POSSIBLE IMPACTED ASTEROID

    SciTech Connect

    Stevenson, R.; Kramer, E. A.; Bauer, J. M.; Masiero, J. R.; Mainzer, A. K.

    2012-11-10

    In this work, we characterize the recently discovered active main belt object P/2012 F5 (Gibbs), which was discovered with a dust trail >7' in length in the outer main belt, 7 months prior to aphelion. We use optical imaging obtained on UT 2012 March 27 to analyze the central condensation and the long trail. We find B-band and R-band apparent magnitudes of 20.96 {+-} 0.04 mag and 19.93 {+-} 0.02 mag, respectively, which give an upper limit on the radius of the nucleus of 2.1 km. The geometric scattering cross-section of material in the trail was {approx}4 Multiplication-Sign 10{sup 8} m{sup 2}, corresponding to a mass of {approx}5 Multiplication-Sign 10{sup 7} kg. Analysis of infrared images taken by the Wide-field Infrared Survey Explorer in 2010 September reveals that the object was below the detection limit, suggesting that it was less active than it was during 2012, or possibly inactive, just six months after it passed through perihelion. We set a 1{sigma} upper limit on its radius during this time of 2.9 km. P/2012 F5 (Gibbs) is dynamically stable in the outer main belt on timescales of {approx}1 Gyr, pointing toward an asteroidal origin. We find that the morphology of the ejected dust is consistent with it being produced by a single event that occurred on UT 2011 July 7 {+-} 20 days, possibly as the result of a collision with a small impactor.

  15. Long-Period Ground Motion In the Arabian Gulf From Earthquakes in the Zagros Mountains Thrust Belt

    NASA Astrophysics Data System (ADS)

    Pitarka, A.; Al-Amri, A. M.; Rodgers, A. J.; Pasyanos, M.; Mellors, R. J.

    2013-12-01

    We will compare observed and modeled ground motions recorded in the western shore of the Arabian Gulf from selected earthquakes in the Zagros Mountains region. Exceptionally long-duration seismic waves with very large amplitude, as compared with ground motion prediction equations developed by Campbell and Bozorgnia (2008) and Boore and Atkinson (2006), are found to occur with periods of 2-10 seconds. These long-period waves may have implications for large structures near the Gulf and therefore it is important to understand the cause. In contrast, the short-period content of ground motion (<2s) at long distances is relatively weak. The long-period waves may be due to waveguide effects in the deep sedimentary basin structure of the Arabian Gulf. Therefore, we performed 3D wave propagation simulations using a finite difference method. Several different velocity models of the Gulf, were tested. The simulation results confirm our hypothesis that long period waves with extremely long duration and relatively large amplitudes are caused by the geometry of the basin sedimentary layers. The depth of the earthquakes is also a factor. Combined effects of basin edge geometry with sharp velocity contrast and shallow sources (< 10km) on the east part of the Arabian Gulf can cause large long period ground motion on the west part of the Gulf. The reduced amplitude of the short-period waves is due to wave propagation scattering and attenuation in the shallow sedimentary layers of the Gulf basin. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

  16. 3D Fault modeling of the active Chittagong-Myanmar fold belt, Bangladesh

    NASA Astrophysics Data System (ADS)

    Peterson, D. E.; Hubbard, J.; Akhter, S. H.; Shamim, N.

    2013-12-01

    The Chittagong-Myanmar fold belt (CMFB), located in eastern Bangladesh, eastern India and western Myanmar, accommodates east-west shortening at the India-Burma plate boundary. Oblique subduction of the Indian Plate beneath the Burma Plate since the Eocene has led to the development of a large accretionary prism complex, creating a series of north-south trending folds. A continuous sediment record from ~55 Ma to the present has been deposited in the Bengal Basin by the Ganges-Brahmaputra-Meghna rivers, providing an opportunity to learn about the history of tectonic deformation and activity in this fold-and-thrust belt. Surface mapping indicates that the fold-and-thrust belt is characterized by extensive N-S-trending anticlines and synclines in a belt ~150-200 km wide. Seismic reflection profiles from the Chittagong and Chittagong Hill Tracts, Bangladesh, indicate that the anticlines mapped at the surface narrow with depth and extend to ~3.0 seconds TWTT (two-way travel time), or ~6.0 km. The folds of Chittagong and Chittagong Hill Tracts are characterized by doubly plunging box-shaped en-echelon anticlines separated by wide synclines. The seismic data suggest that some of these anticlines are cored by thrust fault ramps that extend to a large-scale décollement that dips gently to the east. Other anticlines may be the result of detachment folding from the same décollement. The décollement likely deepens to the east and intersects with the northerly-trending, oblique-slip Kaladan fault. The CMFB region is bounded to the north by the north-dipping Dauki fault and the Shillong Plateau. The tectonic transition from a wide band of E-W shortening in the south to a narrow zone of N-S shortening along the Dauki fault is poorly understood. We integrate surface and subsurface datasets, including topography, geological maps, seismicity, and industry seismic reflection profiles, into a 3D modeling environment and construct initial 3D surfaces of the major faults in this

  17. Late Holocene activity and historical earthquakes of the Qiongxi thrust fault system in the southern Longmen Shan fold-and-thrust belt, eastern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Wang, Maomao; Jia, Dong; Lin, Aiming; Shen, Li; Rao, Gang; Li, Yiquan

    2013-01-01

    The 12 May 2008 Wenchuan earthquake (Mw 7.9) generated a 285-km-long surface rupture zone along the Longmen Shan fold-and-thrust belt (LSFTB) on the eastern margin of Tibetan Plateau. The Wenchuan earthquake did not rupture into the southwestern Longmen Shan, along which there is no evidence for large paleo- or historical earthquakes. Seismic reflection profiles and field investigations reveal that the 50-km-long Qiongxi thrust fault (QTF) of the southern LSFTB is currently active. The QTF consists of three west-dipping ramp segments overlain by fault-bend folds rooted in a regional detachment that transfers shortening from the mountain belt into the Sichuan basin. Trench investigations, coupled with interpretations of seismic reflection profiles and radiocarbon results, show that a recent surface-rupturing earthquake occurred on the QTF during the Late Ming to Qing Dynasty, between AD 1600 and 1800. In addition, seismic reflection profile and topographic analysis indicate the presence of a subtle topographic, produced by kink-band migration folding above a fault bend at about 5 km depth. These findings confirm that the QTF is a significant seismic hazard, and that it should be incorporated into current regional seismic hazard models for the densely populated Sichuan basin.

  18. Sublimation-Driven Activity in Main-Belt Comet 313p/Gibbs

    NASA Astrophysics Data System (ADS)

    Hsieh, Henry H.; Hainaut, Olivier; Novaković, Bojan; Bolin, Bryce; Denneau, Larry; Fitzsimmons, Alan; Haghighipour, Nader; Kleyna, Jan; Kokotanekova, Rosita; Lacerda, Pedro; Meech, Karen J.; Micheli, Marco; Moskovitz, Nick; Schunova, Eva; Snodgrass, Colin; Wainscoat, Richard J.; Wasserman, Lawrence; Waszczak, Adam

    2015-02-01

    We present an observational and dynamical study of newly discovered main-belt comet 313P/Gibbs. We find that the object is clearly active both in observations obtained in 2014 and in precovery observations obtained in 2003 by the Sloan Digital Sky Survey, strongly suggesting that its activity is sublimation-driven. This conclusion is supported by a photometric analysis showing an increase in the total brightness of the comet over the 2014 observing period, and dust modeling results showing that the dust emission persists over at least three months during both active periods, where we find start dates for emission no later than 2003 July 24 ± 10 for the 2003 active period and 2014 July 28 ± 10 for the 2014 active period. From serendipitous observations by the Subaru Telescope in 2004 when the object was apparently inactive, we estimate that the nucleus has an absolute R-band magnitude of HR = 17.1 ± 0.3, corresponding to an effective nucleus radius of re ∼ 1.00 ± 0.15 km. The object’s faintness at that time means we cannot rule out the presence of activity, and so this computed radius should be considered an upper limit. We find that 313P’s orbit is intrinsically chaotic, having a Lyapunov time of Tl = 12,000 yr and being located near two three-body mean-motion resonances with Jupiter and Saturn, 11J-1S-5A and 10J+12S-7A, yet appears stable over >50 Myr in an apparent example of stable chaos. We furthermore find that 313P is the second main-belt comet, after P/2012 T1 (PANSTARRS), to belong to the ∼155 Myr old Lixiaohua asteroid family.

  19. SUBLIMATION-DRIVEN ACTIVITY IN MAIN-BELT COMET 313P/GIBBS

    SciTech Connect

    Hsieh, Henry H.; Hainaut, Olivier; Novaković, Bojan; Bolin, Bryce; Denneau, Larry; Haghighipour, Nader; Kleyna, Jan; Meech, Karen J.; Schunova, Eva; Wainscoat, Richard J.; Fitzsimmons, Alan; Kokotanekova, Rosita; Snodgrass, Colin; Lacerda, Pedro; Micheli, Marco; Moskovitz, Nick; Wasserman, Lawrence; Waszczak, Adam

    2015-02-10

    We present an observational and dynamical study of newly discovered main-belt comet 313P/Gibbs. We find that the object is clearly active both in observations obtained in 2014 and in precovery observations obtained in 2003 by the Sloan Digital Sky Survey, strongly suggesting that its activity is sublimation-driven. This conclusion is supported by a photometric analysis showing an increase in the total brightness of the comet over the 2014 observing period, and dust modeling results showing that the dust emission persists over at least three months during both active periods, where we find start dates for emission no later than 2003 July 24 ± 10 for the 2003 active period and 2014 July 28 ± 10 for the 2014 active period. From serendipitous observations by the Subaru Telescope in 2004 when the object was apparently inactive, we estimate that the nucleus has an absolute R-band magnitude of H{sub R} = 17.1 ± 0.3, corresponding to an effective nucleus radius of r{sub e} ∼ 1.00 ± 0.15 km. The object’s faintness at that time means we cannot rule out the presence of activity, and so this computed radius should be considered an upper limit. We find that 313P’s orbit is intrinsically chaotic, having a Lyapunov time of T{sub l} = 12,000 yr and being located near two three-body mean-motion resonances with Jupiter and Saturn, 11J-1S-5A and 10J+12S-7A, yet appears stable over >50 Myr in an apparent example of stable chaos. We furthermore find that 313P is the second main-belt comet, after P/2012 T1 (PANSTARRS), to belong to the ∼155 Myr old Lixiaohua asteroid family.

  20. Spacing of Rocky Mountain foreland arches and Laramide magmatic activity

    SciTech Connect

    Schmidt, C.J.; Evans, J.P.; Fletcher, R.C.; Spang, J.H.

    1985-01-01

    First-order Late Cretaceous and Paleocene folds in the Rocky Mountain foreland have a spacing (S) ranging from 45 to 300 km. Spacing of folds and major mountain flank thrusts was controlled in part by the depth of the brittle-ductile transition (BDT). Analysis of folding of a brittle layer of thickness H above a ductile substrate suggests S/H approx. = 4-6. Experimental data indicate that the BDT in quartz rich rock occurs at 300/sup 0/ +/- 50/sup 0/C and therefore its depth depends on geothermal gradient. Regions with high Laramide geothermal gradients should have had a shallower depth to the BDT and a shorter spacing of first-order folds than regions with low gradients. A regional compilation for the Montana and Wyoming foreland shows a correlation between the value of S and syntectonic magmatic activity. The mean S value for southwestern Montana, where Late Cretaceous and Paleocene magmatic activity was widespread, is 65 km. This value of S indicates a relatively shallow (11-16 km) depth of the BDT and suggests a relatively high (16-32/sup 0/C/km) Laramide geothermal gradient. The mean S value for the Wyoming foreland, where no syntectonic magmatic activity is indicated, is 150 km. Measurements of S may allow some predictions of depth to rheologically-controlled mid-crustal decoupling zones. They may also indicate areas where the depth to the BDT was not a major control on S. Structures with S < 40 km correspond to inadmissably shallow BDT zones and were probably controlled by other factors such as preexisting fault zones or basement lithology.

  1. Active mountain building in Taiwan in comparison to the early postcollisional evolution of the Alps

    NASA Astrophysics Data System (ADS)

    Ustaszewski, K.; Suppe, J.; Wu, Y.-M.; Huang, S.-T.

    2009-04-01

    Taiwan represent the subaerial part of an active, bivergent thrust belt resulting from the oblique collision between the Luzon island arc of the Philippine Sea Plate and the passive margin of the Eurasian Plate since about 4 to 6.5 Ma. This collision followed the initially intraoceanic subduction of the South China Sea lithosphere below the Philippine Sea Plate, which commenced c. 15 Ma ago and which still prevails south of Taiwan in the Manila accretionary wedge. Considering the collision between Eurasia and the Luzon island arc as one between a large continental plate and a microplate, many analogies can be inferred between currently ongoing mountain building processes in Taiwan and those that occurred in the Alps following closure of the Alpine Tethys in the late Palaeogene. Based on new crustal-scale cross-sections and high-resolution earthquake tomography, we provide an overview of Taiwan's kinematics and compare this to the late Palaeogene evolution of the Alps, a time that marked its transition from an accretionary to a collisional, bivergent orogen. The Taiwan fold-and thrust belt is characterised by actively growing topography, crustal accretion by thrust propagation towards the foreland, a subsiding foreland basin and ongoing tectonic exhumation of metamorphosed continental basement and cover in the retrowedge. Exhumation is controlled by the development of a crustal-scale backfold that overprints earlier fabrics related to foreland-facing transport. Backthrusts within the Eurasian basement that were active at greenschist-facies conditions facilitated exhumation. 40Ar/39Ar ages on synkinematically deformed biotites suggest that backthrusting started as early as between ca. 3-4 Ma, i.e. shortly after or concomitant with the onset of collision between Eurasian passive margin and Luzon island arc. At the internal side of the backfold, blueschist-facies units that likely represent subducted forearc lithosphere are preserved. This structural setting bears some

  2. Geomorphic signature of active tectonics in the southern Abruzzi Periadriatic hilly belt (Central Italy)

    NASA Astrophysics Data System (ADS)

    Racano, Simone; Fubelli, Giandomenico; Centamore, Ernesto; Dramis, Francesco

    2016-04-01

    The geo-structural setting of the southern Abruzzi hilly belt that stretches from the northeastern front of the Maiella Massif to the Adriatic coast is characterized by deep-seated northeast verging thrusts masked by a thick cover of Late Pliocene-Middle Pleistocene marine deposits. Most authors consider this area tectonically inactive while only few of them support the hypothesis of its recent activity from the analysis of the river network pattern. Geological and geomorphological investigations carried out in the area have clearly shown the occurrence of surface deformations resulting from the continued activity of compressive tectonics up to recent times. The analysis of the study area by of a 10 m resolution DTM (using the open-source QGIS software) confirmed and supplemented field observations. Particularly significant in this context is the topographic setting of the alluvial strath terraces in the river valleys that develop transversally to the buried thrusts. In correspondence of these structures, topographic highs have grown up displacing the middle-Pleistocene planation surface developed on top of the hilly belt, from the Maiella piedmont to the coastal zone, and diverting laterally the river courses uphill. In the same places, as along the Alento and Foro rivers that cross by antecedence the grown up topographic highs, the long profiles of terraces bend eastward and the height difference between the terrace orders, essentially related all around the area to the Quaternary regional uplift, strongly increases. In some cases, surficial faults have lowered the terraces into graben troughs or have displaced them until assuming an uphill trend. This recent tectonic activity should be taken in account in assessing the seismic hazard of the study area.

  3. Muscle activation patterns are bilaterally linked during split-belt treadmill walking in humans

    PubMed Central

    Ivanenko, Y. P.; Massaad, F.; Bruijn, S. M.; Duysens, J.; Lacquaniti, F.

    2014-01-01

    There is growing evidence that human locomotion is controlled by flexibly combining a set of basic muscle activity patterns. To explore how these patterns are modified to cope with environmental constraints, 10 healthy young adults 1st walked on a split-belt treadmill at symmetric speeds of 4 and 6 km/h for 2 min. An asymmetric condition was then performed for 10 min in which treadmill speeds for the dominant (fast) and nondominant (slow) sides were 6 and 4 km/h, respectively. This was immediately followed by a symmetric speed condition of 4 km/h for 5 min. Gait kinematics and ground reaction forces were recorded. Electromyography (EMG) was collected from 12 lower limb muscles on each side of the body. Nonnegative matrix factorization was applied to the EMG signals bilaterally and unilaterally to obtain basic activation patterns. A cross-correlation analysis was then used to quantify temporal changes in the activation patterns. During the early (1st 10 strides) and late (final 10 strides) phases of the asymmetric condition, the patterns related to ankle plantar flexor (push-off) of the fast limb and quadriceps muscle (contralateral heel contact) of the slow limb occurred earlier in the gait cycle compared with the symmetric conditions. Moreover, a bilateral temporal alignment of basic patterns between limbs was still maintained in the split-belt condition since a similar shift was observed in the unilateral patterns. The results suggest that the temporal structure of these locomotor patterns is shaped by sensory feedback and that the patterns are bilaterally linked. PMID:24478155

  4. Igneous Activity at Yucca Mountain: Technical Basis for Decision Making

    NASA Astrophysics Data System (ADS)

    Hinze, W.; Marsh, B.; Weiner, R.; Coleman, N.

    2007-12-01

    Eighty thousand years ago a small-volume basaltic volcano erupted 20 km south of the Department of Energy's (DOE) proposed high-level radioactive waste repository at Yucca Mountain, Nevada. Lathrop Wells is one of the infrequent basaltic volcanoes that have occurred near Yucca Mountain during the past 10 million years. The Advisory Committee on Nuclear Waste and Materials (ACNW&M) has prepared a summary and analysis of the technical views on the nature, likelihood and potential consequences of future igneous activity at the proposed repository. The technical views have been abstracted from public literature and agency reports. Alternate views reflect uncertainties of the igneous processes that have occurred in the region and those that are likely to occur, as well as the interaction of these processes with the proposed repository. There is general agreement that either extrusive or intrusive igneous activity may occur. The extrusive scenario is likely to cause a larger risk and the effect is greatest within the first thousand years. The nature of igneous activity that could occur will probably be similar in composition, structure, and style to the Lathrop Wells volcano. Certain styles of volcanism, like explosive phreatic eruptions (maar volcanism) are not expected because conditions necessary for these do not exist at Yucca Mountain. The volcanic record, particularly during the past 5 million years, suggests a variety of models for evaluating the probability of future igneous activity. The anticipated range of probability of an igneous event intersecting the proposed repository is low, between 1E-9 and 1E-7/yr. An ongoing DOE expert elicitation incorporating the latest geophysical and drilling data will provide an up-to-date, credible estimate of the probability of volcanic intersection. An understanding of the processes involved in interaction between magma and drifts, waste packages, and waste is evolving and providing new insights. As a result, there is limited

  5. WATER-ICE-DRIVEN ACTIVITY ON MAIN-BELT COMET P/2010 A2 (LINEAR)?

    SciTech Connect

    Moreno, F.; Ortiz, J. L.; Cabrera-Lavers, A.; Augusteijn, T.; Liimets, T.; Lindberg, J. E.; Pursimo, T.; RodrIguez-Gil, P.; Vaduvescu, O.

    2010-08-01

    The dust ejecta of Main-Belt Comet P/2010 A2 (LINEAR) have been observed with several telescopes at the Observatorio del Roque de los Muchachos on La Palma, Spain. Application of an inverse dust tail Monte Carlo method to the images of the dust ejecta from the object indicates that a sustained, likely water-ice-driven, activity over some eight months is the mechanism responsible for the formation of the observed tail. The total amount of the dust released is estimated to be 5 x 10{sup 7} kg, which represents about 0.3% of the nucleus mass. While the event could have been triggered by a collision, this cannot be determined from the currently available data.

  6. Anatomy and growth of a mountain belt: a look at the Alps from the earth's surface down into the mantle.

    NASA Astrophysics Data System (ADS)

    Schmid, S. M.

    2009-04-01

    is characterized by an impressive amount of Cenozoic N-S-shortening that amounts to some 500km according to kinematic retrodeformations. Thrusting is asymmetric and top-N initially, but completely reworked into a bivergent orogen during Oligocene back thrusting and retro thrusting that pre-dominates during the Miocene. A very thick pile of Austroalpine nappes characterizes the easternmost Alps, floating on European crust. This nappe stack formed during 2 subsequent orogenies, a Cretaceous one that is followed by a Cenozoic one, the two being separated by an extensional phase related to the formation of the Gosau basins. The Cretaceous cycle is related to the closure of a branch of Neotethys, namely the Meliata branch in the east, triggering intra-continental subduction in the Eastern Alps. This event affected the Austroalpine nappe stack only. The Cenozoic cycle, on the other hand, led to the closing of the Alpine Tethys, parts of which are preserved within the Penninic nappe stack; the former Cretaceous orogen now forms the upper plate. However, presently this entire Alpine nappe stack is found in an upper plate position with respect to the eastern part of the Southern Alps where foreland-directed thrusting, linked to that within the external Dinarides, is still active. Hence Cretaceous and Cenozoic Alpine nappe stacking were followed by a third episode, when the easternmost Alps became part of the Dinaridic orogen, within which they presently occupy an upper-plate position.

  7. Export of earthquake-triggered landslides in active mountain ranges: insights from 2D morphodynamic modelling.

    NASA Astrophysics Data System (ADS)

    Croissant, Thomas; Lague, Dimitri; Davy, Philippe; Steer, Philippe

    2016-04-01

    . The model is then applied to a high resolution (5-10 m) digital elevation model of the Poerua catchment in New Zealand which has been impacted by the effect of a large landslide during the last 15 years. We investigate several plausible Alpine Faults earthquake scenarios to study the propagation of the sediment along a complex river network. We characterize and quantify the sediment pulse export time and mechanism for this river configuration and show its impact on the alluvial plain evolution. Our findings have strong implications for the understanding of aggradation rates and the temporal persistence of induced hazards in the alluvial plain as well as of sediment transfers in active mountain belts.

  8. Construction monitoring activities in the Yucca Mountain ESF Starter Tunnel

    SciTech Connect

    Pott, J.; Costin, L.S.; Brechtel, C.E

    1993-12-31

    An underground test facility known as the Exploratory Studies Facility (ESF) is planned as part of the characterization of a site for a potential high-level nuclear waste repository at Yucca Mountain, NV. The first part of the ESF that will be constructed is the North Ramp Starter Tunnel (NRST), which will provide a facility for launching the tunnel-boring machine to be used in the construction of the ESF. Geotechnical monitoring activities are planned for the NRST to provide for the collection of data to confirm design concepts and to enhance safety during construction. This paper describes the activities to be conducted and their objectives. The construction monitoring activities are part of a study defined in the In Situ Design Verification Study Plan. The objectives of this study are to (1) monitor and observe the long-term behavior of openings in a range of ground conditions in the repository host rock, and (2) to observe and evaluate the construction of the ESF with respect to implications for repository construction and performance. Initiating geotechnical monitoring activities in the NRST will allow geotechnical data required to confirm adequate design, construction and long term performance to be collected from the very beginning of underground construction. In addition, the planned monitoring is consistent with standard practice for assuring quality and safety during similar rock excavation for civil construction. The geotechnical monitoring activities addressed by this experiment plan are grouped into three tasks: (1) evaluation of mining methods, (2) monitoring of ground support systems and (3) monitoring drift stability. A general description of each of the tasks is presented below.

  9. Mountains versus valleys: Semiannual variation of geomagnetic activity

    NASA Astrophysics Data System (ADS)

    Cliver, E. W.; Kamide, Y.; Ling, A. G.

    2000-02-01

    The semiannual variation in geomagnetic activity is generally attributed to the Russell-McPherron effect. In that picture, enhancements of southward field Bs near the equinoxes account for the observed higher geomagnetic activity in March and September. In a contrary point of view, we argue that the bulk of the semiannual variation results from an equinoctial effect (based on the ψ angle between the solar wind flow direction and Earth's dipole axis) that makes Bs coupling less effective (by ~25% on average) at the solstices. Thus the semiannual variation is not simply due to ``mountain building'' (creation of Bs) at the equinoxes but results primarily from ``valley digging'' (loss of coupling efficiency) at the solstices. We estimate that this latter effect, which clearly reveals itself in the diurnal variation of the am index, is responsible for ~65% of the semiannual modulation. The characteristic imprint of the equinoctial hypothesis is also apparent in hourly/monthly averages of the time-differential Dst index and the AE index.

  10. Characterize Framework for Igneous Activity at Yucca Mountain, Nevada

    SciTech Connect

    F. Perry; B. Youngs

    2000-11-06

    The purpose of this Analysis/Model (AMR) report is twofold. (1) The first is to present a conceptual framework of igneous activity in the Yucca Mountain region (YMR) consistent with the volcanic and tectonic history of this region and the assessment of this history by experts who participated in the Probabilistic Volcanic Hazard Analysis (PVHA) (CRWMS M&O 1996). Conceptual models presented in the PVHA are summarized and extended in areas in which new information has been presented. Alternative conceptual models are discussed as well as their impact on probability models. The relationship between volcanic source zones defined in the PVHA and structural features of the YMR are described based on discussions in the PVHA and studies presented since the PVHA. (2) The second purpose of the AMR is to present probability calculations based on PVHA outputs. Probability distributions are presented for the length and orientation of volcanic dikes within the repository footprint and for the number of eruptive centers located within the repository footprint (conditional on the dike intersecting the repository). The probability of intersection of a basaltic dike within the repository footprint was calculated in the AMR ''Characterize Framework for Igneous Activity at Yucca Mountain, Nevada'' (CRWMS M&O 2000g) based on the repository footprint known as the Enhanced Design Alternative [EDA II, Design B (CRWMS M&O 1999a; Wilkins and Heath 1999)]. Then, the ''Site Recommendation Design Baseline'' (CRWMS M&O 2000a) initiated a change in the repository design, which is described in the ''Site Recommendation Subsurface Layout'' (CRWMS M&O 2000b). Consequently, the probability of intersection of a basaltic dike within the repository footprint has also been calculated for the current repository footprint, which is called the 70,000 Metric Tons of Uranium (MTU) No-Backfill Layout (CRWMS M&O 2000b). The calculations for both footprints are presented in this AMR. In addition, the

  11. WISE/NEOWISE OBSERVATIONS OF ACTIVE BODIES IN THE MAIN BELT

    SciTech Connect

    Bauer, James M.; Mainzer, A. K.; Masiero, Joseph R.; Blauvelt, Erin K.; Cherry, De'Andre; Grav, Tommy; Walker, Russell G.; McMillan, Robert S.; Scotti, James V.; Fernandez, Yan R.; Kramer, Emily; Meech, Karen J.; Tholen, David J.; Riesen, Timm; Urban, Laurie; Khayat, Alain; Lisse, Carey M.; Cutri, Roc M.; Dailey, John W.; Pearman, George; Collaboration: WISE Team; and others

    2012-03-01

    We report results based on mid-infrared photometry of five active main belt objects (AMBOs) detected by the Wide-field Infrared Survey Explorer (WISE) spacecraft. Four of these bodies, P/2010 R2 (La Sagra), 133P/Elst-Pizarro, (596) Scheila, and 176P/LINEAR, showed no signs of activity at the time of the observations, allowing the WISE detections to place firm constraints on their diameters and albedos. Geometric albedos were in the range of a few percent, and on the order of other measured comet nuclei. P/2010 A2 was observed on 2010 April 2-3, three months after its peak activity. Photometry of the coma at 12 and 22 {mu}m combined with ground-based visible-wavelength measurements provides constraints on the dust particle mass distribution (PMD), dlog n/dlog m, yielding power-law slope values of {alpha} = -0.5 {+-} 0.1. This PMD is considerably more shallow than that found for other comets, in particular inbound particle fluence during the Stardust encounter of comet 81P/Wild 2. It is similar to the PMD seen for 9P/Tempel 1 in the immediate aftermath of the Deep Impact experiment. Upper limits for CO{sub 2} and CO production are also provided for each AMBO and compared with revised production numbers for WISE observations of 103P/Hartley 2.

  12. The Last Glacial Maximum in the Northern European loess belt: Correlations between loess-paleosol sequences and the Dehner Maar core (Eifel Mountains)

    NASA Astrophysics Data System (ADS)

    Zens, Joerg; Krauß, Lydia; Römer, Wolfgang; Klasen, Nicole; Pirson, Stéphane; Schulte, Philipp; Zeeden, Christian; Sirocko, Frank; Lehmkuhl, Frank

    2016-04-01

    The D1 project of the CRC 806 "Our way to Europe" focusses on Central Europe as a destination of modern human dispersal out of Africa. The paleo-environmental conditions along the migration areas are reconstructed by loess-paleosol sequences and lacustrine sediments. Stratigraphy and luminescence dating provide the chronological framework for the correlation of grain size and geochemical data to large-scale climate proxies like isotope ratios and dust content of Greenland ice cores. The reliability of correlations is improved by the development of precise age models of specific marker beds. In this study, we focus on the (terrestrial) Last Glacial Maximum of the Weichselian Upper Pleniglacial which is supposed to be dominated by high wind speeds and an increasing aridity. Especially in the Lower Rhine Embayment (LRE), this period is linked to an extensive erosion event. The disconformity is followed by an intensive cryosol formation. In order to support the stratigraphical observations from the field, luminescence dating and grain size analysis were applied on three loess-paleosol sequences along the northern European loess belt to develop a more reliable chronology and to reconstruct paleo-environmental dynamics. The loess sections were compared to newest results from heavy mineral and grain size analysis from the Dehner Maar core (Eifel Mountains) and correlated to NGRIP records. Volcanic minerals can be found in the Dehner Maar core from a visible tephra layer at 27.8 ka up to ~25 ka. They can be correlated to the Eltville Tephra found in loess section. New quartz luminescence ages from Romont (Belgium) surrounding the tephra dated the deposition between 25.0 + 2.3 ka and 25.8 + 2.4 ka. In the following, heavy minerals show an increasing importance of strong easterly winds during the second Greenland dust peak (~24 ka b2k) correlating with an extensive erosion event in the LRE. Luminescence dating on quartz bracketing the following soil formation yielded ages of

  13. Characterize Framework for Igneous Activity at Yucca Mountain, Nevada

    SciTech Connect

    F. Perry; R. Youngs

    2004-10-14

    The purpose of this scientific analysis report is threefold: (1) Present a conceptual framework of igneous activity in the Yucca Mountain region (YMR) consistent with the volcanic and tectonic history of this region and the assessment of this history by experts who participated in the probabilistic volcanic hazard analysis (PVHA) (CRWMS M&O 1996 [DIRS 100116]). Conceptual models presented in the PVHA are summarized and applied in areas in which new information has been presented. Alternative conceptual models are discussed, as well as their impact on probability models. The relationship between volcanic source zones defined in the PVHA and structural features of the YMR are described based on discussions in the PVHA and studies presented since the PVHA. (2) Present revised probability calculations based on PVHA outputs for a repository footprint proposed in 2003 (BSC 2003 [DIRS 162289]), rather than the footprint used at the time of the PVHA. This analysis report also calculates the probability of an eruptive center(s) forming within the repository footprint using information developed in the PVHA. Probability distributions are presented for the length and orientation of volcanic dikes located within the repository footprint and for the number of eruptive centers (conditional on a dike intersecting the repository) located within the repository footprint. (3) Document sensitivity studies that analyze how the presence of potentially buried basaltic volcanoes may affect the computed frequency of intersection of the repository footprint by a basaltic dike. These sensitivity studies are prompted by aeromagnetic data collected in 1999, indicating the possible presence of previously unrecognized buried volcanoes in the YMR (Blakely et al. 2000 [DIRS 151881]; O'Leary et al. 2002 [DIRS 158468]). The results of the sensitivity studies are for informational purposes only and are not to be used for purposes of assessing repository performance.

  14. Threshold bedrock channels in tectonically active mountains with frequent mass wasting

    NASA Astrophysics Data System (ADS)

    Korup, O.; Hayakawa, Y. S.; Codilean, A.; Oguchi, T.

    2013-12-01

    Models of how mountain belts grow and erode through time largely rely on the paradigm of fluvial bedrock incision as the main motor of response to differences in rock uplift, thus setting base levels of erosion in tectonically active landscapes. Dynamic feedbacks between rock uplift, bedrock river geometry, and mass wasting have been encapsulated within the concept of threshold hillslopes that attain a mechanically critical inclination capable of adjusting to fluvial incision rates via decreased stability and commensurately more frequent landsliding. Here we provide data that challenge the widely held view that channel steepness records tectonic forcing more faithfully than hillslope inclination despite much robust empirical evidence of such links between bedrock-river geometry and hillslope mass wasting. We show that the volume mobilized by mass wasting depends more on local topographic relief and the sinuosity of bedrock rivers than their mean normalized channel steepness. We derive this counterintuitive observation from an unprecedented inventory of ~300,000 landslides covering the tectonically active Japanese archipelago with substantial differences in seismicity, lithology, vertical surface deformation, topography, and precipitation variability. Both total landslide number and volumes increase nonlinearly with mean local relief even in areas where the fraction of steepest channel segments attains a constant threshold well below the maximum topographic relief. Our data document for the first time that mass wasting increases systematically with preferential steepening of flatter channel segments. Yet concomitant changes in mean channel steepness are negligible such that it remains a largely insensitive predictor of landslide denudation. Further, minute increases in bedrock-river sinuosity lead to substantial reduction in landslide abundance and volumes. Our results underline that sinuosity (together with mean local relief) is a key morphometric variable for

  15. Discovery and characteristics of the rapidly rotating active asteroid (62412) 2000 SY178 in the main belt

    SciTech Connect

    Sheppard, Scott S.; Trujillo, Chadwick

    2015-02-01

    We report a new active asteroid in the main belt of asteroids between Mars and Jupiter. Object (62412) 2000 SY178 exhibited a tail in images collected during our survey for objects beyond the Kuiper Belt using the Dark Energy Camera on the CTIO 4 m telescope. We obtained broadband colors of 62412 at the Magellan Telescope, which, along with 62412's low albedo, suggests it is a C-type asteroid. 62412's orbital dynamics and color strongly correlate with the Hygiea family in the outer main belt, making it the first active asteroid known in this heavily populated family. We also find 62412 to have a very short rotation period of 3.33 ± 0.01 hours from a double-peaked light curve with a maximum peak-to-peak amplitude of 0.45 ± 0.01 mag. We identify 62412 as the fastest known rotator of the Hygiea family and the nearby Themis family of similar composition, which contains several known main belt comets. The activity on 62412 was seen over one year after perihelion passage in its 5.6 year orbit. 62412 has the highest perihelion and one of the most circular orbits known for any active asteroid. The observed activity is probably linked to 62412's rapid rotation, which is near the critical period for break-up. The fast spin rate may also change the shape and shift material around 62412's surface, possibly exposing buried ice. Assuming 62412 is a strengthless rubble pile, we find the density of 62412 to be around 1500 kg m{sup −3}.

  16. Discovery and Characteristics of the Rapidly Rotating Active Asteroid (62412) 2000 SY178 in the Main Belt

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott S.; Trujillo, Chadwick

    2015-02-01

    We report a new active asteroid in the main belt of asteroids between Mars and Jupiter. Object (62412) 2000 SY178 exhibited a tail in images collected during our survey for objects beyond the Kuiper Belt using the Dark Energy Camera on the CTIO 4 m telescope. We obtained broadband colors of 62412 at the Magellan Telescope, which, along with 62412's low albedo, suggests it is a C-type asteroid. 62412's orbital dynamics and color strongly correlate with the Hygiea family in the outer main belt, making it the first active asteroid known in this heavily populated family. We also find 62412 to have a very short rotation period of 3.33 ± 0.01 hours from a double-peaked light curve with a maximum peak-to-peak amplitude of 0.45 ± 0.01 mag. We identify 62412 as the fastest known rotator of the Hygiea family and the nearby Themis family of similar composition, which contains several known main belt comets. The activity on 62412 was seen over one year after perihelion passage in its 5.6 year orbit. 62412 has the highest perihelion and one of the most circular orbits known for any active asteroid. The observed activity is probably linked to 62412's rapid rotation, which is near the critical period for break-up. The fast spin rate may also change the shape and shift material around 62412's surface, possibly exposing buried ice. Assuming 62412 is a strengthless rubble pile, we find the density of 62412 to be around 1500 kg m-3.

  17. Connecting the Yakima fold and thrust belt to active faults in the Puget Lowland, Washington

    USGS Publications Warehouse

    Blakely, R.J.; Sherrod, B.L.; Weaver, C.S.; Wells, R.E.; Rohay, A.C.; Barnett, E.A.; Knepprath, N.E.

    2011-01-01

    High-resolution aeromagnetic surveys of the Cascade Range and Yakima fold and thrust belt (YFTB), Washington, provide insights on tectonic connections between forearc and back-arc regions of the Cascadia convergent margin. Magnetic surveys were measured at a nominal altitude of 250 m above terrain and along flight lines spaced 400 m apart. Upper crustal rocks in this region have diverse magnetic properties, ranging from highly magnetic rocks of the Miocene Columbia River Basalt Group to weakly magnetic sedimentary rocks of various ages. These distinctive magnetic properties permit mapping of important faults and folds from exposures to covered areas. Magnetic lineaments correspond with mapped Quaternary faults and with scarps identified in lidar (light detection and ranging) topographic data and aerial photography. A two-dimensional model of the northwest striking Umtanum Ridge fault zone, based on magnetic and gravity data and constrained by geologic mapping and three deep wells, suggests that thrust faults extend through the Tertiary section and into underlying pre-Tertiary basement. Excavation of two trenches across a prominent scarp at the base of Umtanum Ridge uncovered evidence for bending moment faulting possibly caused by a blind thrust. Using aeromagnetic, gravity, and paleoseismic evidence, we postulate possible tectonic connections between the YFTB in eastern Washington and active faults of the Puget Lowland. We suggest that faults and folds of Umtanum Ridge extend northwestward through the Cascade Range and merge with the Southern Whidbey Island and Seattle faults near Snoqualmie Pass 35 km east of Seattle. Recent earthquakes (MW ≤ 5.3) suggest that this confluence of faults may be seismically active today.

  18. Connecting the Yakima fold and thrust belt to active faults in the Puget Lowland, Washington

    NASA Astrophysics Data System (ADS)

    Blakely, Richard J.; Sherrod, Brian L.; Weaver, Craig S.; Wells, Ray E.; Rohay, Alan C.; Barnett, Elizabeth A.; Knepprath, Nichole E.

    2011-07-01

    High-resolution aeromagnetic surveys of the Cascade Range and Yakima fold and thrust belt (YFTB), Washington, provide insights on tectonic connections between forearc and back-arc regions of the Cascadia convergent margin. Magnetic surveys were measured at a nominal altitude of 250 m above terrain and along flight lines spaced 400 m apart. Upper crustal rocks in this region have diverse magnetic properties, ranging from highly magnetic rocks of the Miocene Columbia River Basalt Group to weakly magnetic sedimentary rocks of various ages. These distinctive magnetic properties permit mapping of important faults and folds from exposures to covered areas. Magnetic lineaments correspond with mapped Quaternary faults and with scarps identified in lidar (light detection and ranging) topographic data and aerial photography. A two-dimensional model of the northwest striking Umtanum Ridge fault zone, based on magnetic and gravity data and constrained by geologic mapping and three deep wells, suggests that thrust faults extend through the Tertiary section and into underlying pre-Tertiary basement. Excavation of two trenches across a prominent scarp at the base of Umtanum Ridge uncovered evidence for bending moment faulting possibly caused by a blind thrust. Using aeromagnetic, gravity, and paleoseismic evidence, we postulate possible tectonic connections between the YFTB in eastern Washington and active faults of the Puget Lowland. We suggest that faults and folds of Umtanum Ridge extend northwestward through the Cascade Range and merge with the Southern Whidbey Island and Seattle faults near Snoqualmie Pass 35 km east of Seattle. Recent earthquakes (MW ≤ 5.3) suggest that this confluence of faults may be seismically active today.

  19. Earthquake related VLF activity and Electron Precipitation as a Major Agent of the Inner Radiation Belt Losses

    NASA Astrophysics Data System (ADS)

    Anagnostopoulos, Georgios C.; Sidiropoulos, Nikolaos; Barlas, Georgios

    2015-04-01

    The radiation belt electron precipitation (RBEP) into the topside ionosphere is a phenomenon which is known for several decades. However, the inner radiation belt source and loss mechanisms have not still well understood, including PBEP. Here we present the results of a systematic study of RBEP observations, as obtained from the satellite DEMETER and the series of POES satellites, in comparison with variation of seismic activity. We found that a type of RBEP bursts lasting for ~1-3 min present special characteristics in the inner region of the inner radiation belt before large (M >~7, or even M>~5) earthquakes (EQs), as for instance: characteristic (a) flux-time profiles, (b) energy spectrum, (c) electron flux temporal evolution, (d) spatial distributions (e) broad band VLF activity, some days before an EQ and (f) stopping a few hours before the EQ occurrence above the epicenter. In this study we present results from both case and statistical studies which provide significant evidence that, among EQs-lightings-Earth based transmitters, strong seismic activity during a substorm makes the main contribution to the long lasting (~1-3 min) RBEP events at middle latitudes.

  20. Scenarios constructed for basaltic igneous activity at Yucca Mountain and vicinity; Yucca Mountain Site Characterization Project

    SciTech Connect

    Barr, G.E.; Dunn, E.; Dockery, H.; Barnard, R.; Valentine, G.; Crowe, B.

    1993-08-01

    Basaltic volcanism has been identified as a possible future event initiating a release of radionuclides from a potential repository at the proposed Yucca Mountain high-level waste repository site. The performance assessment method set forth in the Site Characterization Plan (DOE, 1988) requires that a set of scenarios encompassing all significant radionuclide release paths to the accessible environment be described. This report attempts to catalogue the details of the interactions between the features and processes produced by basaltic volcanism in the presence of the presumed groundwater flow system and a repository structure, the engineered barrier system (EBS), and waste. This catalogue is developed in the form of scenarios. We define a scenario as a well-posed problem, starting from an initiating event or process and proceeding through a logically connected and physically possible combination or sequence of features, events, and processes (FEPs) to the release of contaminants.

  1. Active Prompting to Decrease Cell Phone Use and Increase Seat Belt Use while Driving

    ERIC Educational Resources Information Center

    Clayton, Michael; Helms, Bridgett; Simpson, Cathy

    2006-01-01

    Automobile crashes are the leading cause of death for those aged 3 to 33, with 43,005 (118 per day) Americans killed in 2002 alone. Seat belt use reduces the risk of serious injury in an accident, and refraining from using a cell phone while driving reduces the risk of an accident. Cell phone use while driving increases accident rates, and leads…

  2. Active Fault Mapping of Naga-Disang Thrust (Belt of Schuppen) for Assessing Future Earthquake Hazards in NE India

    NASA Astrophysics Data System (ADS)

    Kumar, A.

    2014-12-01

    We observe the geodynamic appraisal of Naga-Disang Thrust North East India. The Disang thrust extends NE-SW over a length of 480 km and it defines the eastern margin of Neogene basin. It branches out from Haflong-Naga thrust and in the NE at Bulbulia in the right bank of Noa Dihing River, it is terminated by Mishmi thrust, which extends into Myanmar as 'Sagaing fault,which dip generally towards SE. It extends between Dauki fault in the SW and Mishmi thrust in the NE. When the SW end of 'Belt of Schuppen' moved upwards and towards east along the Dauki fault, the NE end moved downwards and towards west along the Mishmi thrust, causing its 'S' shaped bending. The SRTM generated DEM is used to map the topographic expression of the schuppen belt, where these thrusts are significantly marked by topographic break. Satellite imagery map also shows presence lineaments supporting the post tectonic activities along Naga-Disang Thrusts. The southern part of 'Belt of Schuppen' extends along the sheared western limb of southerly plunging Kohima synform, a part of Indo Burma Ranges (IBR) and it is seismically active.The crustal velocity at SE of Schuppen is 39.90 mm/yr with a azimuth of 70.780 at Lumami, 38.84 mm/yr (Azimuth 54.09) at Senapati and 36.85 mm/yr (Azimuth 54.09) at Imphal. The crustal velocity at NW of Schuppen belt is 52.67 mm/yr (Azimuth 57.66) near Dhauki Fault in Meghalaya. It becomes 43.60 mm/yr (Azimuth76.50) - 44.25 (Azimuth 73.27) at Tiding and Kamlang Nagar around Mishmi thrust. The presence of Schuppen is marked by a change in high crustal velocity from Indian plate to low crustal velocity in Mishmi Suture as well as Indo Burma Ranges. The difference in crustal velocities results in building up of strain along the Schuppen which may trigger a large earthquake in the NE India in future. The belt of schuppean seems to be seismically active, however, the enough number of large earthquakes are not recorded. These observations are significant on Naga

  3. Status of data, major results, and plans for geophysical activities, Yucca Mountain Project

    SciTech Connect

    Oliver, H.W.; Hardin, E.L.; Nelson, P.H.

    1990-07-01

    This report describes past and planned geophysical activities associated with the Yucca Mountain Project and is intended to serve as a starting point for integration of geophysical activities. This report relates past results to site characterization plans, as presented in the Yucca Mountain Site Characterization Plan (SCP). This report discusses seismic exploration, potential field methods, geoelectrical methods, teleseismic data collection and velocity structural modeling, and remote sensing. This report discusses surface-based, airborne, borehole, surface-to-borehole, crosshole, and Exploratory Shaft Facility-related activities. The data described in this paper, and the publications discussed, have been selected based on several considerations; location with respect to Yucca Mountain, whether the success or failure of geophysical data is important to future activities, elucidation of features of interest, and judgment as to the likelihood that the method will produce information that is important for site characterization. 65 refs., 19 figs., 12 tabs.

  4. Modelling "reality" in tectonics: Simulation of the mechanical evolution of the Jura Mountains-Molasse Basin system, and routes to forward-inverse modelling of fold thrust belts.

    NASA Astrophysics Data System (ADS)

    Hindle, David; Kley, Jonas

    2016-04-01

    The ultimate validation of any numerical model of any geological process comes when it can accurately forward model a case study from the geological record. However, as the example of the Jura-Molasse fold thrust belt demonstrates, geological information on even the most basic aspects of the present day state of such systems is highly incomplete and usually known only with large uncertainties. Fold thrust-belts are studied and understood by geologists in an iterative process of constructing their subsurface geometries and structures (folds, faults, bedding etc) based on limited subsurface information from boreholes, tunnels or seismic data where available, and surface information on outcrops of different layers and their dips. This data is usually processed through geometric models which involve conservation of line length of different beds over the length of an entire cross section. Constructing such sections is the art of cross section balancing. A balanced cross section can be easily restored to its pre-deformation state, assuming (usually) originally horizontal bedding to remove the effects of folding and faulting. Such a pre-deformation state can then form an initial condition for a forward mechanical model of the section. A mechanical model introduces new parameters into the system such as rock elasticity, cohesion, and frictional properties. However, a forward mechanical model can also potentially show the continuous evolution of a fold thrust belt, including dynamic quantities like stress. Moreover, a forward mechanical model, if correct in most aspects, should match in its final state, the present day geological cross section it is simulating. However, when attempting to achieve a match between geometric and mechanical models, it becomes clear that many more aspects of the geodynamic history of a fold thrust belt have to be taken into account. Erosion of the uppermost layers of an evolving thrust belt is the most obvious one of these. This can potentially

  5. Tomographic image of a seismically active volcano: Mammoth Mountain, California

    USGS Publications Warehouse

    Dawson, Phillip B.; Chouet, Bernard A.; Pitt, Andrew M.

    2016-01-01

    High-resolution tomographic P wave, S wave, and VP/VS velocity structure models are derived for Mammoth Mountain, California, using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (5.1 × 109 to 5.9 × 1010m3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ∼2 km below sea level. We infer that the reduction in seismic wave velocities is due to the presence of CO2 distributed in oblate spheroid pores with mean aspect ratio α = 1.6 × 10−3 to 7.9 × 10−3 (crack-like pores) and mean gas volume fraction ϕ = 8.1 × 10−4 to 3.4 × 10−3. The pore density parameter κ = 3ϕ/(4πα) = na3=0.11, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to be 4.6 × 109 to 1.9 × 1011 kg. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 500 tons day−1, the reservoir could supply the emission of CO2 for ∼25–1040 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  6. Tomographic image of a seismically active volcano: Mammoth Mountain, California

    NASA Astrophysics Data System (ADS)

    Dawson, Phillip; Chouet, Bernard; Pitt, Andrew

    2016-01-01

    High-resolution tomographic P wave, S wave, and VP/VS velocity structure models are derived for Mammoth Mountain, California, using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (5.1 × 109 to 5.9 × 1010m3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ˜2 km below sea level. We infer that the reduction in seismic wave velocities is due to the presence of CO2 distributed in oblate spheroid pores with mean aspect ratio α = 1.6 × 10-3 to 7.9 × 10-3 (crack-like pores) and mean gas volume fraction ϕ = 8.1 × 10-4 to 3.4 × 10-3. The pore density parameter κ = 3ϕ/(4πα) = na3=0.11, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to be 4.6 × 109 to 1.9 × 1011 kg. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 500 tons day-1, the reservoir could supply the emission of CO2 for ˜25-1040 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  7. Tomographic Image of a Seismically Active Volcano: Mammoth Mountain, California

    NASA Astrophysics Data System (ADS)

    Dawson, P. B.; Chouet, B. A.; Pitt, A. M.

    2015-12-01

    High-resolution tomographic P wave, S wave, and VP /VS velocity structure models are derived for Mammoth Mountain, California using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (˜50 km3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ˜2 km below sea level. We infer that the reduction in seismic wave velocities is primarily due to the presence of CO2 distributed in oblate-spheroid pores with mean aspect ratio α ˜8 x 10-4 (crack-like pores) and gas volume fraction φ ˜4 x 10-4. The pore density parameter κ = 3φ / (4πα) = na3 = 0.12, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to range up to ˜1.6 x 1010 kg if the pores exclusively contain CO2, although he presence of an aqueous phase may lower this estimate by up to one order of magnitude. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 5 x 105 kg day-1, the reservoir could supply the emission of CO2 for ˜8 to ˜90 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  8. Pn anisotropic tomography under the entire Tienshan orogenic belt

    NASA Astrophysics Data System (ADS)

    Zhou, Zhigang; Lei, Jianshe

    2015-11-01

    We present a new anisotropic tomography of the uppermost mantle under the Tienshan orogenic belt and surrounding regions using a number of Pn arrival-time data hand-picked from portable seismic stations and chosen from the Xinjiang provincial observation bulletins and the EHB datasets. Our results exhibit prominent lateral heterogeneities in the study region. Distinct low-velocity anomalies are visible under the tectonically active regions, such as the Tienshan orogenic belt and western Kunlun Mountains, whereas pronounced high-velocity anomalies are imaged beneath the stable blocks, such as the Kazakh shield, the Junggar, Tarim, Qaidam, and Turpan-Hami basins, and the Tajik depression. Most strong earthquakes (Ms > 7.0) are mainly distributed along the transition zone of high to low velocity anomalies, suggesting a possible correlation between the strong earthquakes and the upper mantle structure. The fast directions of Pn anisotropy beneath the Tienshan orogenic belt are generally parallel to its striking orientation, whereas those beneath Pamir show a northward arc-shaped distribution. The Pn fast-velocity directions on the boundaries of the Kazakh shield and the Tarim and Junngar basins are approximately perpendicular to the strike of the Tienshan orogenic belt. By integrating with previous findings, our results suggest that the Tarim and Kazakh lithospheric materials could have underthrusted beneath the Tienshan orogenic belt that leads to the hot mantle material upwelling under the Tienshan orogenic belt, which is attributable to the Indo-Asian collision. These dynamic processes could play important roles in the Tienshan mountain building.

  9. Atmospheric Research and Public Outreach Activities at Grandfather Mountain, North Carolina

    NASA Astrophysics Data System (ADS)

    Perry, B.; Pope, J.; Kelly, G.; Sherman, J. P.; Taubman, B.

    2012-12-01

    Promoting scientific and public understanding of mountain meteorological processes, particularly in the context of climate variability and change, remains a formidable challenge. Mountain environments present considerable difficulties in the collection of surface and atmospheric observations due to complex topography and resulting high spatial and temporal variability of the atmospheric processes. A collaborative partnership between Appalachian State University (ASU) and the Grandfather Mountain Stewardship Foundation (GMSF) in the southern Appalachian Mountains of North Carolina has provided an outstanding opportunity to integrate atmospheric research and outreach activities. The NASA-funded Climate Action Network through Direct Observations and Outreach (CAN-DOO) project directly supports the research and education activities and places them in the context of climate variability and change. This paper introduces the manual observations and citizen science activities, automated meteorological measurements, and public outreach initiatives on Grandfather Mountain and presents preliminary findings. In support of project objectives, GMSF staff makes daily measurements of precipitation, snow water equivalent, snow depth, and aerosol optical depth, while also encouraging citizen scientists to participate in the daily meteorological measurements. Team members have developed real-time displays of meteorological conditions for the two main visitor's centers and website, and have also created interactive climate science public displays. ASU scientists and GMSF staff have worked together to install and operate two research-quality meteorological stations at 1609 m asl that measure temperature, relative humidity, wind speed and direction, pressure, precipitation, and present weather. Preliminary results of research activities suggest that extreme wind gusts >50 m s -1 and severe icing due to riming and freezing rain are a frequent occurrence on Grandfather Mountain

  10. Active Faulting and Pore-Fluid Pressure in the Taiwan Thrust Belt

    NASA Astrophysics Data System (ADS)

    Yue, L.; Suppe, J.

    2004-12-01

    compaction trend shown by sonic log data using standard petroleum techniques that show the magnitude of uplift and erosion and the fossil and present pore-fluid pressures. The fossil top of the overpressured zone in several wells drilled through major thrusts and eroded anticlines is at a substantially higher (~1-2 km) stratigraphic level than the present top of fluid pressures, but never reaches the level of the Pliocene Chinshui Shale. It implies uplift and erosion of the active fold-and-thrust belt causes a major drop in fluid pressures in the formerly overpressured zone. Finally, a preliminary estimate of Hubbert-Rubey fluid pressure ratio needed to slide the Chelungpu thrust sheet (and also the Changhua thrust) using normal Byerlee's Law friction is about 0.8 (which is higher than any observed fluid pressures even within the deeper overpressured zone). Therefore the Hubbert and Rubey mechanism of static excess fluid pressure does not appear to be important for major thrusts such as the Chelungpu thrust that slipped in the Chi-Chi earthquake. The many other proposed non-Hubbert-Rubey mechanisms of reduction of fault strength should be considered, including dynamical mechanisms, fluid-pressure transients and non Byerlee coefficients of friction.

  11. The Mountain West and the World: International Connections and Alternative Futures. A Handbook of 15 Activities for Secondary Classrooms.

    ERIC Educational Resources Information Center

    Smith, Gary R.; Bienstock, Eric M.

    Activities to supplement secondary school global or future studies courses in the 10 state Mountain West region are presented in this teacher handbook. Material is divided into 3 sections. Section 1, an introduction to international connectedness, contains 7 activities focusing on the Mountain West's interdependence with the rest of the world. A…

  12. Provenance of Marine Sediment in the Gulf of Alaska, IODP Expedition 341: Links Between Sediment Derivation, Glacial Systems, and Exhumation of the Coastal Mountain Belts

    NASA Astrophysics Data System (ADS)

    Allen, W. K.; Dunn, C. A.; Enkelmann, E.; Ridgway, K.; Colliver, L.

    2015-12-01

    Provenance analysis of Neogene sand and diamict beds from marine boreholes drilled by the IODP Expedition 341 provides a marine sedimentary record of the interactions between tectonics, climate and sediment deposition along a glaciated convergent margin. The 341 boreholes represent a cross-margin transect that sampled the continental shelf, slope, and deep sea Surveyor Fan of the Gulf of Alaska. Our dataset currently consists of ~ 650 detrital zircons selected for double dating method utilizing both detrital zircon fission track (FT) and U-Pb analysis from sand and diamict beds, as well as zircon U-Pb geochronology and apatite FT from igneous and gneissic clasts. Detrital zircon U-Pb geochronology of sand records dominant peak ages of 53, 62, 70, and 98 Ma with minor populations of 117, 154, and 170 Ma. Most of these ages can be correlated to primary igneous sources in the Coast Plutonic Complex, the Chugach Metamorphic Complex, the plutonic rocks of Wrangellia, and the Sanak-Baranoff plutonic belt. All samples analyzed to date, covering a 10 Myr range, share nearly identical detrital zircon populations suggesting similar primary sediment sources and reworking of sediment in thrust belts and accretionary prisms along this convergent margin. Plutonic and gneissic clasts collected from the boreholes on the shelf have already been double dated. These clasts have general U-Pb zircon crystallization ages of 52-54 Ma and apatite fission track cooling ages of 10-12 Ma. These results, along with previous published studies, indicate that these clasts were derived from the Chugach Metamorphic Complex and were eroded and transported by the Bagley Ice Field and Bering Glacier. Future results using this approach should allow us to pinpoint which parts of the exhumed onshore ranges and which glacial systems provided sediment to marine environments in the Gulf of Alaska.

  13. Incipient Crustal Stretching across AN Active Collision Belt: the Case of the Siculo-Calabrian Rift Zone (central Mediterranean)

    NASA Astrophysics Data System (ADS)

    Catalano, S.; Tortorici, G.; Romagnoli, G.; Pavano, F.

    2012-12-01

    In the Central Mediterranean, the differential roll-back of the subducting Nubia Plate caused the Neogene-Quaternary extrusion of the Calabrian arc onto the oceanic Ionian slab, and the opening of the oceanic Tyrrhenian Basin, in the overriding Eurasia Plate. The differential motion at the edges of the arc was largely accommodated along transform faults that propagated across the orogenic belt. Since the Late Quaternary, the southern edge of the arc has been replaced by the roughly N-S oriented Siculo-Calabrian Rift Zone (SCRZ) that formed as the NNW-directed normal faults of NE Sicily, crossing the orogenic belt, have linked the NNE-oriented Tyrrhenian margin of southern Calabria with the NNW-trending Africa-Ionian boundary of southeastern Sicily. Our study focused on the Sicily shoulder of the SCRZ, where the transition zone between the extensional belt and the still active Nubia-Eurasia convergent margin is characterized by two distinct mobile crustal wedges, both lying on an upwarped Mantle, where a re-orientations of the σ1 is combined with volcanism (e.g. Etna, Aeolian islands) and a huge tectonic uplift. In southeastern Sicily, the Hyblean-Etnean region evolved, since about 0.85 Ma, as an indipendent crustal wedge, moving towards the NNW and pointing to the active Mt. Etna volcano. A local ENE crustal stretching accompanied the traslation of the block and pre-dated the ESE-oriented extension governing the propagation of the southernmost branch of the SCR, which started at about 330 ka B.P.. Similarly, the Peloritani-Aeolian region, flanked by the 125 ka-old NE-Sicily branch of the rift zone, represents a mostly submerged crustal wedge that migrates towards the NE, diverging from the rest of the Sicily collision zone and pointing to the Stromboli volcano. The Peloritani-Aeolian block is characterized by the occurrence of a wide central NE-oriented collapsed basin contoured by an actively uplifting region, whose tectonic boundaries are evidenced by a sharp

  14. Effect of lunar phase on summer activity budgets of Rocky Mountain elk (Cervus elaphus nelsonii)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rocky Mountain elk (Cervus elaphus) exist in a complex biological and social environment that is marked by necessary diurnal activities such as foraging, ruminating, and resting. It has long been understood that elk demonstrate circadian rhythms. One of the most predictable variables that could af...

  15. Mountain-Plains Master Course List. Curriculum Areas: Job Titles: Learning Activity Packages: Courses: Units.

    ERIC Educational Resources Information Center

    Mountain-Plains Education and Economic Development Program, Inc., Glasgow AFB, MT.

    The document contains a master listing of all Mountain-Plains curriculum, compiled by job title, course, unit and LAP (Learning Activity Package), and arranged in numerical order by curriculum area. Preceding each curriculum area is a page of explanatory notes describing the curriculum area and including relevant job descriptions. Where a job…

  16. The world mountain Damavand: documentation and monitoring of human activities using remote sensing data

    NASA Astrophysics Data System (ADS)

    Kostka, Robert

    The use of different remote sensing data is demonstrated by example of the world mountain, Mt. Damavand (5671 m) in the Alborz Mountains, Iran. Several types of satellite data were required to master the complex task of preparing a monograph of this mountain: SSEOP images of NASA, Russian KFA-1000 pictures, CORONA panoramic images of NASA and Russian KVR-1000 orthoimages. Examples of climatic studies, transportation routes, water resources, conservation areas and relicts of human land-use are presented in order to show the potential of remote sensing data. The right choice of image data is a top priority in applied remote sensing in order to obtain significant results in the documentation and monitoring of human activities.

  17. Three dimensional visualization in support of Yucca Mountain Site characterization activities

    SciTech Connect

    Brickey, D.W.

    1992-02-01

    An understanding of the geologic and hydrologic environment for the proposed high-level nuclear waste repository at Yucca Mountain, NV is a critical component of site characterization activities. Conventional methods allow visualization of geologic data in only two or two and a half dimensions. Recent advances in computer workstation hardware and software now make it possible to create interactive three dimensional visualizations. Visualization software has been used to create preliminary two-, two-and-a-half-, and three-dimensional visualizations of Yucca Mountain structure and stratigraphy. The three dimensional models can also display lithologically dependent or independent parametric data. Yucca Mountain site characterization studies that will be supported by this capability include structural, lithologic, and hydrologic modeling, and repository design.

  18. Crustal differentiation due to partial melting of granitic rocks in an active continental margin, the Ryoke Belt, Southwest Japan

    NASA Astrophysics Data System (ADS)

    Akasaki, Eri; Owada, Masaaki; Kamei, Atsushi

    2015-08-01

    The continental margin of Pacific Asia is dominated by the voluminous Cretaceous to Paleogene granitic rocks. The Ryoke granitoids that occur in the Ryoke Belt in the Southwest Japan Arc are divided into the older and younger granites. The high-K Kibe Granite represents the younger granitic intrusion and is exposed in the Yanai area in the western part of Ryoke Belt. The Kibe Granite is associated with the coeval Himurodake Quartz Diorite and their intrusive age is 91 Ma. However, the Gamano-Obatake Granodiorite, the older granite, intruded the host Ryoke gneisses at 95 Ma. The Gamano-Obatake Granodiorite is characterized by the localized development of migmatitic structure attributed to the intrusion of the Himurodake Quartz Diorite into the granodiorite. Leucocratic pools and patches occur in the granodiorite in the vicinity of the quartz diorite. The Sr and Nd isotopic compositions of the Gamano-Obatake Granodiorite corrected to 91 Ma are plotted within those of the Kibe Granite. Geochemical modeling suggests that partial melting took place in the Gamano-Obatake Granodiorite and resulted in the formation of the Kibe Granite magma. The Himurodake Quartz Diorite is believed to be a heat source for this event. This can be considered as an essential process for the formation of the evolved younger Ryoke granite and for the crustal differentiation in the active continental margin.

  19. Feedback between erosion and active deformation: geomorphic constraints from the frontal Jura fold-and-thrust belt (eastern France)

    NASA Astrophysics Data System (ADS)

    Madritsch, Herfried; Fabbri, Olivier; Hagedorn, Eva-Marie; Preusser, Frank; Schmid, Stefan M.; Ziegler, Peter A.

    2010-10-01

    A regional tectono-geomorphic analysis indicates a Pliocene to recent rock uplift of the outermost segment of the Jura fold-and-thrust belt, which spatially coincides with the intra-continental Rhine-Bresse Transfer Zone. Elevated remnants of the partly eroded Middle Pliocene Sundgau-Forêt de Chaux Gravels identified by heavy mineral analyses allow for a paleo-topographic reconstruction that yields minimum regional Latest Pliocene to recent rock uplift rates of 0.05 ± 0.02 mm/year. This uplift also affected the Pleistocene evolution of the Ognon and Doubs drainage basins and is interpreted as being tectonically controlled. While the Ognon River was deflected from the uplifted region the Doubs deeply incised into it. Focused incision of the Doubs possibly sustained ongoing deformation along anticlines which were initiated during the Neogene evolution of the thin-skinned Jura fold-and-thrust belt. At present, this erosion-related active deformation is taking place synchronously with thick-skinned tectonics, controlling the inversion of the Rhine-Bresse Transfer Zone. This suggests local decoupling between seismogenic basement faulting and erosion-related deformation of the Mesozoic cover sequences.

  20. The “Main-Belt Comets” are not comets, nor active asteroids; they are temporary shaken asteroids

    NASA Astrophysics Data System (ADS)

    Tancredi, Gonzalo

    2015-08-01

    Several objects in asteroidal orbits have presented comaes and tails similar to the ones presented by comets for short period of times. There are at present 16 objects in this group. Several hypotheses have been proposed to explain the activity of this object [Jewitt 2012]. Among them, the most accepted scenario for many objects is the ice sublimation and the ejection of dust, in a similar way as the cometary activity. Therefore several authors have coined these objects “Main Belt Comets” [Hsieh & Jewitt 2006]. Nevertheless, in some cases, some authors have concluded that the ejection of dust must be due to an impact.We propose an alternative model for the formation of the dusty comaes and tails.The impact of a small body against a larger one initially produces a crater and the ejection of dust at high velocity (>100 m/s). The dust is rapidly dispersed and it should be only observable just after the impact. In addition the impact generates a shock wave, which propagates to the body interior. The asteroid is globally shaken. Material is ejected at low velocities from the entire surface, similar to the low escape velocities at the surface. The particles move away from the asteroid due to the solar radiation pressure, forming the thin tails aligned with the orbital plane. These tails could persist for various months, as they have been seen in these objects.In addition, chunks of rock could be ejected in suborbital flights lasting for days; which, at return they would induce a new low-velocity ejection of particles. This process can explain some of the long-lasting events.The recurrence of the activity for some objects could be explained due to the collision with a dense meteor shower present in the main-belt.The so-called “Main Belt Comets” could be explained with a hypothesis that does not require the presence of ice on the surface of these objects. We also do not favor the term “Activated asteroids”, because it implies some kind of endogenous process

  1. [Modeling of species distribution using topography and remote sensing data, with vascular plants of the Tukuringra Range low mountain belt (Zeya state Nature Reserve, Amur Region) as a case study].

    PubMed

    Dudov, S V

    2016-01-01

    On the basis of maximum entropy method embedded in MaxEnt software, the cartographic models are designed for spatial distribution of 63 species of vascular plants inhabiting low mountain belt of the Tukuringra Range. Initial data for modeling were actual points of a species occurrence, data on remote sensing (multispectral space snapshots by Landsat), and a digital topographic model. It is found out that the structure of factors contributing to the model is related to species ecological amplitude. The distribution of stenotopic species is determined, mainly, by the topography, which thermal and humidity conditions of habitats are associated with. To the models for eurytopic species, variables formed on the basis of remote sensing contribute significantly, those variables encompassing the parameters of the soil-vegetable cover. In course of the obtained models analyzing, three principal groups of species are revealed that have similar distribution pattern. Species of the first group are restricted in their distribution by the slopes of the. River Zeya and River Giluy gorges. Species of the second group are associated with the southern macroslope of the range and with southern slopes of large rivers' valleys. The third group incorporates those species that are distributed over the whole territory under study. PMID:27266017

  2. Change in biochemical and morphological characteristics of Lonicera caerulea in tectonically active zone of the Dzhazator River Valley (Altai Mountains)

    NASA Astrophysics Data System (ADS)

    Boyarskikh, I. G.; Khudyaev, S. A.; Platonova, S. G.; Kolotukhin, S. P.; Shitov, A. V.; Kukushkina, T. A.; Chankina, O. V.

    2012-12-01

    Local geophysical and geochemical anomalies affect the polymorphism of taste variations, berry shape, and content of some biologically active substances in Lonicera caerulea leaves in the tectonically active Altai Mountains (Dzhazator River basin).

  3. The Presence of a Stable Block bounded by Active Zones (Mobile Belts) in the southwestern North American Proterozoic craton

    NASA Astrophysics Data System (ADS)

    Goodell, P.; Martinez P, C.; Mahar, M. A.

    2014-12-01

    Bouguer gravity data, initial Sr isotope values, zircon U-Pb, and multiple occurrences of felsic Proterozoic rocks, have revealed an elevated, less deformed, felsic cratonic block in the northern Mexico. The block is situated in western Chihuahua and is bounded by active zones or mobile belts on three sides, and is here referred to as the Western Chihuahua Cratonic Block (WCCB). Bouguer gravity data clearly indicate a region of a highly negative anomaly (< -200 mgal) in contrast to adjoining areas. The region is large and the anomaly is relatively smooth over broad areas; the WCCB appears as a smaller version of the Colorado Plateau. The block is characterized by high initial Sr isotope ratios (<0.706). Several occurrences of Proterozoic rocks are located within or next to the WCCB, and they reveal the character of the Bouguer anomaly. On the east, at Los Filtros, Proterozoic rocks crop out in a basement cored uplift interpreted to having been derived from the WCCB during the Ouachita orogeny. At Sierra La Mojina boulders of 1.1 Ga granites are found in Permian conglomerates. And at Basasiachic, xenoliths of 1.1 Ga granites are present in ash flow tuffs. Establishment of the Precambrian character of the WCCB is of importance, and these multiple occurrences are evidence. Prior studies of the Sierra Madre Occidental suggest that the region was uplifted because of a vast Cenozoic batholith presumed to lie under the SLIP (Silicic Large Igneous Province), the Upper Volcanic Series. The present study challenges that conclusion and maintains the SMO is underlain by Proterozoic silicic crust. The geology of age dated samples supports this. The WCCB is surrounded on three sides by Active Zones or Mobile Belts, which have been active extensional and translational zones periodically over a long period of time. On the east are the Paleozoic Pedrogosa Basin, Mesozoic Chihuahua Trough and Cenozoic Rio Grande Rift, the first two of which also continue around the northern border

  4. Geologic evolution of the Jemez Mountains and their potential for future volcanic activity

    SciTech Connect

    Burton, B.W.

    1982-01-01

    Geophysical and geochemical data and the geologic history of the Rio Grande rift and the vicinity of the Jemez Mountains are summarized to determine the probability of future volcanic activity in the Los Alamos, New Mexico area. The apparent cyclic nature of volcanism in the Jemez Mountains may be related to intermittent thermal inputs into the volcanic system beneath the region. The Jemez lineament, an alignment of late Cenozoic volcanic centers that crosses the rift near Los Alamos, has played an important role in the volcanic evolution of the Jemez Mountains. Geophysical data suggest that there is no active shallow magma body beneath the Valles caldera, though magma probably exists at about 15 km beneath this portion of the rift. The rate of volcanism in the Jemez Mountains during the last 10 million years has been 5 x 10/sup -9//km/sup 2//y. Lava or ash flows overriding Laboratory radioactive waste disposal sites would have little potential to release radionuclides to the environment. The probability of a new volcano intruding close enough to a radioactive waste disposal site to effect radionuclide release is 2 x 10/sup -7//y.

  5. Ambient tremors in a collisional orogenic belt

    USGS Publications Warehouse

    Chuang, Lindsay Yuling; Chen, Kate Huihsuan; Wech, Aaron G.; Byrne, Timothy; Peng, Wei

    2014-01-01

    Deep-seated tectonic tremors have been regarded as an observation tied to interconnected fluids at depth, which have been well documented in worldwide subduction zones and transform faults but not in a collisional mountain belt. In this study we explore the general features of collisional tremors in Taiwan and discuss the possible generation mechanism. In the 4 year data, we find 231 ambient tremor episodes with durations ranging from 5 to 30 min. In addition to a coseismic slip-induced stress change from nearby major earthquake, increased tremor rate is also highly correlated with the active, normal faulting earthquake swarms at the shallower depth. Both the tremor and earthquake swarm activities are confined in a small, area where the high attenuation, high thermal anomaly, the boundary between high and low resistivity, and localized veins on the surfaces distributed, suggesting the involvement of fluids from metamorphic dehydration within the orogen.

  6. Tectonics of the Tongbai-Dabie fold belt

    NASA Astrophysics Data System (ADS)

    Wenpu, Ma

    The Qinling fold belt is the northernmost branch of the Paleozoic and Mesozoic Tethys in eastern Asia and contains all the inter-reacting records of the North China Block (NCB) and the South China Block (SCB). The Tongbai-Dabie fold belt is its eastern section. The Qinling belt was a collage of two orogens. The north Qinling is a late Paleozoic collision orogen, which started with Proterozoic rifting, transforming into active continental margin during the middle Ordovician. The intermitten ophiolite fragments indicate the existence of an oceanic crust at that time. The collision that occurred in the Devonian was an east-west diachronous process. The main suture zone is marked by ophiolitic melange extending nearly 500 km. The late Mesozoic molasse, volcano-plutonic activity and huge imbricate thrust system all respond to the further shortening of the crust and adjustment of the intracontinental strain. The south Qinling east of the Nanyang Basin is located to the south of Tongbai mountain. A pile of thick Sinian-Silurian volcanic and marine clastic deposits imply another marine incursion. Its history in south Shaanxi could continue to the Mesozoic. The flysch trough represented by Xinyang group may be the key area for revealing the relationship between north and south Qinling. The discussion in the paper is mainly focused on the nature and evolution of the Tongbai-Dabie fold belt.

  7. Barberton greenstone belt volcanism: Succession, style and petrogenesis

    NASA Technical Reports Server (NTRS)

    Byerly, G. R.; Lowe, D. R.

    1986-01-01

    The Barberton Mountain Land is an early Archean greenstone belt along the eastern margin of the Kaapvaal Craton of southern Africa. Detailed mapping in the southern portion of the belt leads to the conclusion that a substantial thickness is due to original deposition of volcanics and sediments. In the area mapped, a minimum thickness of 12km of predominantly mafic and ultramafic volcanics comprise the Komati, Hooggenoeg, and Kromberg Formations of the Onverwacht Group, and at least one km of predominantly pyroclastic and epiclastic sediments derived from dacitic volcanics comprise the Fig Tree Group. The Barberton greenstone belt formed primarily by ultramafic to mafic volcanism on a shallow marine platform which underwent little or no concurrent extension. Vents for this igneous activity were probably of the non-constructional fissure type. Dacitic volcanism occurred throughout the sequence in minor amounts. Large, constructional vent complexes were formed, and explosive eruptions widely dispersed pyroclastic debris. Only in the final stages of evolution of the belt did significant thrust-faulting occur, generally after, though perhaps overlapping with, the final stage of dacitic igneous activity. A discussion follows.

  8. Correlation of the Applegate Group in the Oregon Klamath Mountains with terranes of the western Paleozoic and Triassic belt in California

    SciTech Connect

    Barnes, C.G.; Tomlinson, S.L. . Dept. of Geosciences); Donato, M.M. )

    1993-04-01

    F.G. Wells' 1955 definition (U.S.G.S map MF-38) of the Applegate Group encompasses all metamorphic rocks in the western Paleozoic and Triassic belt (TrPz) in Oregon. In an attempt to understand the nature and origin of the Applegate Group, the authors have mapped two adjacent areas in southernmost Oregon and have geochemically analyzed representative metavolcanic and metasedimentary rocks. They recognize two lithologic units within the Applegate Group: (1) interbedded volcanogenic metasandstone and argillite, and (2) block-on-block ophiolitic melange that contains metaserpentinite, marble, metabasite, metagabbro, and siliceous metasedimentary rocks. In the Bolan Lake area, the volcanogenic rocks structurally overlie ophiolitic melange along a thrust fault and occupy a N-S trending graben that developed prior to 153 Ma. In both areas the volcanogenic units are characterized by crystal-lithic arenites and conglomerates. Plagioclase, clinopyroxene, and brown hornblende occurs as phenocrysts in lithic clasts and as individual detrital grains. Low-Ca pyroxene is absent. They interpret the volcanogenic units to represent submarine fan deposits on the basis of graded bedding, partial Bouma sequences, rip-up clasts, and channelized conglomerates. Geochemical compositions of the volcanogenic rocks from both areas are identical, with higher Zr/Ti and P/Ti ratios than those of the orphiolitic melange. The volcanogenic rocks are lithologically and compositionally identical to the western Hayfork terrane, which structurally overlies the Rattlesnake Creek terrane in California. The lithology and geochemistry of the ophiolitic melange are identical to those of the Rattlesnake Creek terrane in California. Therefore they correlate the Applegate Group south of approximately 42 [degree] 15[prime]N with these terranes in the TrPz in California.

  9. Predicting mountain lion activity using radiocollars equipped with mercury tip-sensors

    USGS Publications Warehouse

    Janis, Michael W.; Clark, Joseph D.; Johnson, Craig

    1999-01-01

    Radiotelemetry collars with tip-sensors have long been used to monitor wildlife activity. However, comparatively few researchers have tested the reliability of the technique on the species being studied. To evaluate the efficacy of using tip-sensors to assess mountain lion (Puma concolor) activity, we radiocollared 2 hand-reared mountain lions and simultaneously recorded their behavior and the associated telemetry signal characteristics. We noted both the number of pulse-rate changes and the percentage of time the transmitter emitted a fast pulse rate (i.e., head up) within sampling intervals ranging from 1-5 minutes. Based on 27 hours of observations, we were able to correctly distinguish between active and inactive behaviors >93% of the time using a logistic regression model. We present several models to predict activity of mountain lions; the selection of which to us would depend on study objectives and logistics. Our results indicate that field protocols that use only pulse-rate changes to indicate activity can lead to significant classification errors.

  10. [Changes in arterial pressure and adrenergic activity during a holiday at a mountain at low altitude].

    PubMed

    Palatini, P; Businaro, R; Berton, G; Rossi, G P; Zanin, L; Bongiovì, S; Casiglia, E; Pessina, A C; Dal Palù, C

    1989-05-01

    To answer the question often asked by hypertensive patients whether it is advisable for them to spend a holiday in the mountains for fear of a rise in blood pressure, 12 untreated mild hypertensive and 12 normotensive subjects underwent 24-hour non-invasive blood pressure monitoring, plasma catecholamines assay (HPLC) and plasma renin activity determination at home (sea level) and in a mountain resort (1210 m). The 2 evaluations (at home and in the mountains) were performed in a cross-over fashion. The ICR Spacelabs Pressuromaster and the Del Mar Avionics Pressurometer IV were used: blood pressure was measured every 8 minutes during daytime and every 15 minutes during sleep. Blood pressure was also recorded during a 1.5 to 3 hour excursion by cable-car to a height of 3006 m. Average 24-hour blood pressure at sea level was 134/86.7 mmHg in the hypertensive subjects and 115.8/73.6 mmHg in the normotensive ones. At 1210 m, it rose to 140.6/90.2 mmHg (n.s.) and to 120.8/74.9 mmHg (n.s.) respectively. Twenty-four-hour profiles showed that the blood pressure difference was present only during waking hours, while during sleep blood pressure levels were similar at sea level and in the mountains.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2767378

  11. Aspects of igneous activity significant to a repository at Yucca Mountain, Nevada

    SciTech Connect

    Krier, D. J.; Perry, F. V.

    2004-01-01

    Location, timing, volume, and eruptive style of post-Miocene volcanoes have defined the volcanic hazard significant to a proposed high-level radioactive waste (HLW) and spent nuclear fuel (SNF) repository at Yucca Mountain, Nevada, as a low-probability, high-consequence event. Examination of eruptive centers in the region that may be analogueues to possible future volcanic activity at Yucca Mountain have aided in defining and evaluating the consequence scenarios for intrusion into and eruption above a repository. The probability of a future event intersecting a repository at Yucca Mountain has a mean value of 1.7 x 10{sup -8} per year. This probability comes from the Probabilistic Volcanic Hazard Assessment (PVHA) completed in 1996 and updated to reflect change in repository layout. Since that time, magnetic anomalies representing potential buried volcanic centers have been identified fiom magnetic surveys; however these potential buried centers only slightly increase the probability of an event intersecting the repository. The proposed repository will be located in its central portion of Yucca Mountain at approximately 300m depth. The process for assessing performance of a repository at Yucca Mountain has identified two scenarios for igneous activity that, although having a very low probability of occurrence, could have a significant consequence should an igneous event occur. Either a dike swarm intersecting repository drifts containing waste packages, or a volcanic eruption through the repository could result in release of radioactive material to the accessible environment. Ongoing investigations are assessing the mechanisms and significance of the consequence scenarios. Lathrop Wells Cone ({approx}80,000 yrs), a key analogue for estimating potential future volcanic activity, is the youngest surface expression of apparent waning basaltic volcanism in the region. Cone internal structure, lavas, and ash-fall tephra have been examined to estimate eruptive volume

  12. Tracking small mountainous river derived terrestrial organic carbon across the active margin marine environment

    NASA Astrophysics Data System (ADS)

    Childress, L. B.; Blair, N. E.; Orpin, A. R.

    2015-12-01

    Active margins are particularly efficient in the burial of organic carbon due to the close proximity of highland sources to marine sediment sinks and high sediment transport rates. Compared with passive margins, active margins are dominated by small mountainous river systems, and play a unique role in marine and global carbon cycles. Small mountainous rivers drain only approximately 20% of land, but deliver approximately 40% of the fluvial sediment to the global ocean. Unlike large passive margin systems where riverine organic carbon is efficiently incinerated on continental shelves, small mountainous river dominated systems are highly effective in the burial and preservation of organic carbon due to the rapid and episodic delivery of organic carbon sourced from vegetation, soil, and rock. To investigate the erosion, transport, and burial of organic carbon in active margin small mountainous river systems we use the Waipaoa River, New Zealand. The Waipaoa River, and adjacent marine depositional environment, is a system of interest due to a large sediment yield (6800 tons km-2 yr-1) and extensive characterization. Previous studies have considered the biogeochemistry of the watershed and tracked the transport of terrestrially derived sediment and organics to the continental shelf and slope by biogeochemical proxies including stable carbon isotopes, lignin phenols, n-alkanes, and n-fatty acids. In this work we expand the spatial extent of investigation to include deep sea sediments of the Hikurangi Trough. Located in approximately 3000 m water depth 120 km from the mouth of the Waipaoa River, the Hikurangi Trough is the southern extension of the Tonga-Kermadec-Hikurangi subduction system. Piston core sediments collected by the National Institute of Water and Atmospheric Research (NIWA, NZ) in the Hikurangi Trough indicate the presence of terrestrially derived material (lignin phenols), and suggest a continuum of deposition, resuspension, and transport across the margin

  13. Six hundred years of agricultural activity in the Gorce Mountains (Polish Carpathians)

    NASA Astrophysics Data System (ADS)

    Bucała, Anna

    2016-04-01

    The role of human activity on agricultural land use were studied in the Ochotnica village (105 km2) with Jaszcze and Jamne catchments (the Gorce Mountains in Polish Carpathians) from the beginning of human settlement to present-day with special emphasise on the period 1846-2009. The visual interpretation of cadastral maps and air photos, combined with palynological and radiocarbon data as well as analysis of historical and census reports indicates more permanent conversion of land-cover of the Gorce Mountains were started by the expansion of Wallachian shepherds at the turn of the 14th and 15th centuries. In the years 1846-2009, there was an increase in the forest area of Ochotnica by 77%, and in the Jaszcze and Jamne catchment by 29% and 43%, respectively. The arable land decreased in that period by 94% in both catchments. The period of 163 years shows diverging trends and dynamics of land use, referring to the three stages of the socio-economic development observed in the Polish Carpathians. Until World War II, agriculture was the main source of income of the growing rural population. The contribution of the agricultural land was approximately 70% in the 1930s., reaching the highest level in the history of human activity in the Gorce Mountains. After World War II, because of a shortage of food in the communist economy, the pressure on land cultivation resulted in the keep of the land use structure inherited from the past. The transition from the communist economy to a free market after 1989 and the accession of Poland to the European Union, forced a rapid increase in forest area at the expense of the agricultural land. They were the most significant land use changes from the time of the Wallachians' colonization of the Gorce Mountains. The changes in land use contributed to a decrease in the intensity of soil erosion on the slopes and an increase of channel incision in the both streams and Ochotnica river, draining the area of 107.6 km2 of the Gorce Mountains

  14. The effects of video-based and activity-based instruction on high school students' knowledge, attitudes, and behavioral intentions related to seat belt use

    NASA Astrophysics Data System (ADS)

    Jones, Tudor Griffith, III

    The purpose of this study was to determine the effect of video-based science instruction and accompanying activity-based instruction on the knowledge, attitudes, and behavioral intentions of high school students' use of seat belts. Secondarily, the purpose was to determine order effects and interactions between the two treatments used in the study: video-based instruction and hands-on activity-based instruction. The study used Ajzen and Fishbein's theory of reasoned action to investigate the factors influencing high school students' behavioral intentions regarding seat belt use. This study used a pretest-posttest-posttest treatment design. Data were collected on 194 students in high school introductory biology and chemistry classes in Gainesville, Florida. Ten intact high school science classes (eight treatment and two control) took pretests and posttests measuring physics knowledge, attitudes, and behavioral intentions toward seat belt use prior to and after participating in the two treatments. The treatment group students participated in at least 500 minutes of instructional time divided among five lessons over 10 instructional days. All participants were pretested on physics knowledge, attitudes, and behavioral intentions toward seat belt use prior to two treatments. Treatment A was defined as participating in one 50-minute video-based instructional lesson. Treatment B was defined as participating in four hands-on science activities regarding crash-related physics concepts. Cronbach's coefficient alpha was used for analysis of the researcher-designed instruments, and ANOVA was used to analyze the data. The results of the analyses (p < .004) revealed that students who participated in either treatment showed significant differences in knowledge gains on 75% of the test items. The sequence of treatments did not produce significant differences in groups' posttest 2 knowledge mean scores. Combining the treatments resulted in higher mean knowledge scores than either

  15. An exhumed Late Paleozoic canyon in the rocky mountains

    USGS Publications Warehouse

    Soreghan, G.S.; Sweet, D.E.; Marra, K.R.; Eble, C.F.; Soreghan, M.J.; Elmore, R.D.; Kaplan, S.A.; Blum, M.D.

    2007-01-01

    Landscapes are thought to be youthful, particularly those of active orogenic belts. Unaweep Canyon in the Colorado Rocky Mountains, a large gorge drained by two opposite-flowing creeks, is an exception. Its origin has long been enigmatic, but new data indicate that it is an exhumed late Paleozoic landform. Its survival within a region of profound late Paleozoic orogenesis demands a reassessment of tectonic models for the Ancestral Rocky Mountains, and its form and genesis have significant implications for understanding late Paleozoic equatorial climate. This discovery highlights the utility of paleogeomorphology as a tectonic and climatic indicator. ?? 2007 by The University of Chicago. All rights reserved.

  16. Chemical weathering within high mountain depositional structures

    NASA Astrophysics Data System (ADS)

    Emberson, R.; Hovius, N.; Hsieh, M.; Galy, A.

    2013-12-01

    Material eroded from active mountain belts can spend extended periods in depositional structures within the mountain catchments before reaching its final destination. This can be in the form of colluvial fills, debris fans, or alluvial valley fills and terraces. The existence of these landforms is testament to the catastrophic nature of the events that lead to their formation. Sourced by landslides or debris flows, the material that forms them is in many cases either unweathered or incompletely weathered (e.g. Hsieh and Chyi 2010). Due to their porosity and permeability, these deposits likely serve as locations for extensive chemical weathering within bedrock landscapes. Recent studies considering the weathering flux from active mountain belts (e.g. Calmels et al. 2011) have distinguished between shallow and deep groundwater in terms of the contribution to the solute budget from a catchment; in this study we have attempted to more tightly constrain the sources of these groundwater components in the context of the previously mentioned depositional structures. We have collected water samples from a large number of sites within the Chen-you-lan catchment (370 km2) in central west Taiwan to elucidate the location of chemical weathering as well as how the sourcing of weathering products varies depending on the meteorological conditions. Central Taiwan has good attributes for this work considering both the extremely active tectonics and tropical climate, (including extensive cyclonic activity) which stimulate both extensive physical erosion (Dadson et al. 2003) and chemical weathering (Calmels et al. 2011). The Chen-you-lan catchment in particular contains some of the largest alluvial deposits inside the Taiwan mountain belt (Hsieh and Chyi 2010). Our preliminary results suggest that weathering within intramontane deposits may be a significant source of solutes, with the hyporheic systems within mountain rivers of particular import. This input of solutes occurs over

  17. Effects of a Pelvic Belt on the EMG Activity of the Abdominal Muscles during a Single-leg Hold in the Hook-lying Position on a Round Foam Roll.

    PubMed

    Kim, Yu-Ri; Kim, Ji-Won; An, Duk-Hyun; Yoo, Won-Gyu; Oh, Jae-Seop

    2013-07-01

    [Purpose] This study investigated the effects of a pelvic belt on the electromyography (EMG) activity of the abdominal muscles during a single-leg hold in the hook-lying position on a round foam roll. [Subjects] Seventeen healthy female volunteers were recruited for this study. [Methods] The participants performed single-leg-hold exercises on a round foam roll with and without a pelvic belt. Surface EMG was recorded from the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) bilaterally. [Results] The EMG activity of the bilateral RA, EO, and IO was significantly lower when the pelvic belt applied. [Conclusions] Our finding that the bilateral EO, IO, and RA muscles were less active with a pelvic belt during trunk-stabilizing exercises on an unstable surface suggests that the pelvic belt provided "form closure". PMID:24259855

  18. Lifespan of mountain ranges scaled by feedbacks between landsliding and erosion by rivers.

    PubMed

    Egholm, David L; Knudsen, Mads F; Sandiford, Mike

    2013-06-27

    An important challenge in geomorphology is the reconciliation of the high fluvial incision rates observed in tectonically active mountain ranges with the long-term preservation of significant mountain-range relief in ancient, tectonically inactive orogenic belts. River bedrock erosion and sediment transport are widely recognized to be the principal controls on the lifespan of mountain ranges. But the factors controlling the rate of erosion and the reasons why they seem to vary significantly as a function of tectonic activity remain controversial. Here we use computational simulations to show that the key to understanding variations in the rate of erosion between tectonically active and inactive mountain ranges may relate to a bidirectional coupling between bedrock river incision and landslides. Whereas fluvial incision steepens surrounding hillslopes and increases landslide frequency, landsliding affects fluvial erosion rates in two fundamentally distinct ways. On the one hand, large landslides overwhelm the river transport capacity and cause upstream build up of sediment that protects the river bed from further erosion. On the other hand, in delivering abrasive agents to the streams, landslides help accelerate fluvial erosion. Our models illustrate how this coupling has fundamentally different implications for rates of fluvial incision in active and inactive mountain ranges. The coupling therefore provides a plausible physical explanation for the preservation of significant mountain-range relief in old orogenic belts, up to several hundred million years after tectonic activity has effectively ceased. PMID:23803847

  19. The variety of subaerial active salt deformations in the Kuqa fold-thrust belt (China) constrained by InSAR

    NASA Astrophysics Data System (ADS)

    Colón, Cindy; Webb, A. Alexander G.; Lasserre, Cécile; Doin, Marie-Pierre; Renard, François; Lohman, Rowena; Li, Jianghai; Baudoin, Patrick F.

    2016-09-01

    Surface salt bodies in the western Kuqa fold-thrust belt of northwestern China allow study of subaerial salt kinematics and its possible correlations with weather variations. Ephemeral subaerial salt exposure during the evolution of a salt structure can greatly impact the subsequent development and deformation of its tectonic setting. Here, we present a quantitative time-lapse survey of surface salt deformation measured from interferometric synthetic aperture radar (InSAR) using Envisat radar imagery acquired between 2003 and 2010. Time series analysis and inspection of individual interferograms confirm that the majority of the salt bodies in western Kuqa are active, with significant InSAR observable displacements at 3 of 4 structures studied in the region. Subaerial salt motion toward and away from the satellite at rates up to 5 mm/yr with respect to local references. Rainfall measurements from the Tropical Rainfall Measuring Mission (TRMM) and temperature from a local weather station are used to test the relationship between seasonality and surface salt motion. We observe decoupling between surface salt motion and seasonality and interpret these observations to indicate that regional and local structural regimes exert primary control on surface salt displacement rates.

  20. Rates of Periglacial Activity Along an Elevational Gradient, White Mountains, California

    NASA Astrophysics Data System (ADS)

    Schmid, G. L.; Wilkerson, F. D.

    2009-12-01

    Periglacial research has been conducted in the alpine zone of the White Mountains since 1991 and has been integrated with the international Global Observation Research Initiative in Alpine Environments (GLORIA) project since 2005. Study sites range from 3200 m at the southern end of the research area to 4250 m near the summit of White Mountain Peak. This elevation range includes measurements on a variety of lithologies and across several micro-climates. Wooden dowels are used to measure annual vertical movement and surface markers are used to measure horizontal movement. Dowels and markers are placed in grid patterns in a variety of active small-scale sorted circles (frost boils) that often lie within large-scale relict sorted polygons. Rates of vertical movement have decreased since measurements began with an average of 16.8 cm in 1991-1992 decreasing to an average of 10.6 cm between 2005-2009. Surface markers are more consistent with an average of between 31 to 56% of markers being overturned depending upon site location. Temperature (frequency of freeze-thaw cycles) and available water are the driving mechanisms for the surface movement with wet years showing greater rates of activity than dry years. Climate change has significantly decreased activity in the lower elevations, while high elevation sites near the summit remain highly active.

  1. Laterally bendable belt conveyor

    DOEpatents

    Peterson, William J.

    1985-01-01

    An endless, laterally flexible and bendable belt conveyor particularly adapted for coal mining applications in facilitating the transport of the extracted coal up- or downslope and around corners in a continuous manner is disclosed. The conveying means includes a flat rubber belt reinforced along the middle portion thereof along which the major portion of the belt tension is directed so as to cause rotation of the tubular shaped belt when trammed around lateral turns thus preventing excessive belt bulging distortion between adjacent belt supports which would inhibit belt transport. Pretension induced into the fabric reinforced flat rubber belt by conventional belt take-up means supports the load conveyed when the belt conveyor is making lateral turns. The carrying and return portions of the belt are supported and formed into a tubular shape by a plurality of shapers positioned along its length. Each shaper is supported from above by a monorail and includes clusters of idler rollers which support the belt. Additional cluster rollers in each shaper permit the belt supporting roller clusters to rotate in response to the belt's operating tension imposed upon the cluster rollers by induced lateral belt friction forces. The freely rotating roller clusters thus permit the belt to twist on lateral curves without damage to itself while precluding escape of the conveyed material by effectively enclosing it in the tube-shaped, inner belt transport length.

  2. TOSPAC calculations in support of the COVE 2A benchmarking activity; Yucca Mountain Site Characterization Project

    SciTech Connect

    Gauthier, J.H.; Zieman, N.B.; Miller, W.B.

    1991-10-01

    The purpose of the the Code Verification (COVE) 2A benchmarking activity is to assess the numerical accuracy of several computer programs for the Yucca Mountain Site Characterization Project of the Department of Energy. This paper presents a brief description of the computer program TOSPAC and a discussion of the calculational effort and results generated by TOSPAC for the COVE 2A problem set. The calculations were performed twice. The initial calculations provided preliminary results for comparison with the results from other COVE 2A participants. TOSPAC was modified in response to the comparison and the final calculations included a correction and several enhancements to improve efficiency. 8 refs.

  3. Collision and mountain building

    NASA Astrophysics Data System (ADS)

    Trifonov, V. G.

    2016-01-01

    The spatial, chronological, and genetic relationships of recent (Late Alpine) collisions to mountain building are considered at three levels of scale: (i) in separate zones of the Arabian-Caucasus segment of the Alpine-Himalayan Orogenic Belt, (ii) throughout the central segment of this belt from the Alps to the Himalalayas, and (iii) in Central Asia and other mountain belts of continents. Three stages of mountain building are distinguished at all three levels. The first stage starts with widespread collision and similar plate interactions from the end of the Eocene to the middle Miocene and is expressed in the formation of uplifts, commonly no higher than the moderately elevated level in regions that concentrate deformations of transverse shortening induced by compression. The second short stage, which embraces the Pliocene-Quaternary and occasionally the end of the Miocene, differs in general, though differentiated in the value and intensification of vertical movements, when the height of mountains increases by 2-3 times. Elevations are spread over certain platform territories and even frameworks of rift zones. This is related not so much to the intensity of compression and shortening as to the compositional transformation of the upper mantle and the lower crust, leading to their decompaction. Comparison with the Hercynian and Caledonian orogenic stages shows that the second phase, predetermined by widespread collision, reflects a more important geodynamic event expressed in a change of the global plate interaction system and its deep-seated sources.

  4. Bat activity in harvested and intact forest stands in the allegheny mountains

    USGS Publications Warehouse

    Owen, S.F.; Menzel, M.A.; Edwards, J.W.; Ford, W.M.; Menzel, J.M.; Chapman, B.R.; Wood, P.B.; Miller, K.V.

    2004-01-01

    We used Anabat acoustical monitoring devices to examine bat activity in intact canopy forests, complex canopy forests with gaps, forests subjected to diameter-limit harvests, recent deferment harvests, clearcuts and unmanaged forested riparian areas in the Allegheny Mountains of West Virginia in the summer of 1999. We detected eight species of bats, including the endangered Indiana bat (Myotis sodalis). Most bat activity was concentrated in forested riparian areas. Among upland habitats, activity of silver-haired bats (Lasionycteris noctivagans) and hoary bats (Lasiurus cinereus) was higher in open, less cluttered vegetative types such as recent deferment harvests and clearcuts. Our results suggest that bat species in the central Appalachians partially segregate themselves among vegetative conditions based on differences in body morphology and echolocation call characteristics. From the standpoint of conserving bat foraging habitat for the maximum number of species in the central Appalachians, special emphasis should be placed on protecting forested riparian areas.

  5. The Effects of Site Characterization Activities on the Abundance of Ravens (Corvus corax) in the Yucca Mountain Area

    SciTech Connect

    P.E. Lederle

    1998-05-08

    In response to the Nuclear Waste Policy Act of 1982 and the Nuclear Waste Policy Amendments Act of 1987, the U.S. Department of Energy (DOE) developed and is implementing the Yucca Mountain Site Characterization Project. Raven abundance was measured from August 1991 through August 1995 along treatment and control routes to evaluate whether site characterization activities resulted in increased raven abundance at Yucca Mountain. This study fulfills the requirement set forth in the incidental take provisions of the Biological Opinion that DOE monitor the abundance of ravens at Yucca Mountain. Ravens were more abundant at Yucca Mountain than in the control area, and raven abundance in both areas increased over time. However, the magnitude of differences between Yucca Mountain and control surveys did not change over time, indicating that the increase in raven abundance observed during this study was not related to site characterization activities. Increases over time on both Yucca Mountain and control routes are consistent with increases in raven abundance in the Mojave Desert reported by the annual Breeding Bird Survey of the US. Fish and Wildlife Service. Evidence from the Desert Tortoise Monitoring Program at Yucca Mountain suggests that ravens are not a significant predator of small tortoises in this locale. Carcasses of small tortoises (less than 110 mm in length) collected during the study showed little evidence of raven predation, and 59 radiomarked hatchlings that were monitored on a regular basis were not preyed upon by ravens. Overall, no direct evidence of raven predation on tortoises was observed during this study. Small tortoises are probably encountered so infrequently by ravens that they are rarely exploited as a food source. This is likely due to the relatively low abundance of both desert tortoises and ravens in the Yucca Mountain area.

  6. The Yakima Fold and Thrust Belt - a paradigm for active shortening in the Columbia embayment from Pasco to the Pacific Ocean (Invited)

    NASA Astrophysics Data System (ADS)

    Wells, R. E.; Blakely, R. J.; Sherrod, B. L.; Weaver, C. S.

    2009-12-01

    The Yakima Fold Belt (YFB), a series of nearly east-west trending folds and associated thrusts, accommodates N-S shortening in the 16-6 Ma Columbia River Basalt Group (CRBG) and younger strata in the western Columbia Plateau. The folds are commonly asymmetric and north verging, with broad, south dipping back limbs and short, steep, fore-limbs. The YFB lies within the Columbia embayment, an oroclinal bend in the Mesozoic orogen between the Klamath Mountains and the North Cascades, long considered to be the result of northwest motion of California in late Cenozoic time. YFB-style deformation is not restricted to the YFB; it fans westward across the Cascades and is superimposed on the subduction-related arc, Puget-Willamette trough, and Coast Range. New geophysical data link the YFB across the Cascades to the active South Whidbey Island and Seattle Faults in the Puget Lowland, generally along the broadly defined Olympic-Wallowa Lineament (OWL). South of Puget Sound, the east-west Doty Fault, the Columbia River Syncline (controlling the location of the Columbia River across the Coast Range), and the post-CRBG folding in the northern Willamette Valley are all late Cenozoic YFB-related structures accommodating N-S shortening in the forearc. This geologic evidence indicates that the Columbia embayment is the locus of extensive post middle Miocene shortening, and there is abundant paleoseismic evidence for large Holocene earthquakes on these structures in Puget Lowland and in the YFB. Seismicity in the embayment is characterized by thrust and strike slip focal mechanisms, with P axes oriented approximately N-S. GPS results of McCaffrey et al. (2007) indicate that folding in the embayment is driven by the clockwise rotation of Oregon about a pole near the OR-WA-ID border, compressing Washington against slow-moving Canada. The folds fan westward from this pole of rotation, and shortening increases to the west to about 7.1 mm/yr between Astoria and Penticton, BC. Shortening

  7. Influence of Traffic Activity on Heavy Metal Concentrations of Roadside Farmland Soil in Mountainous Areas

    PubMed Central

    Zhang, Fan; Yan, Xuedong; Zeng, Chen; Zhang, Man; Shrestha, Suraj; Devkota, Lochan Prasad; Yao, Tandong

    2012-01-01

    Emission of heavy metals from traffic activities is an important pollution source to roadside farmland ecosystems. However, little previous research has been conducted to investigate heavy metal concentrations of roadside farmland soil in mountainous areas. Owing to more complex roadside environments and more intense driving conditions on mountainous highways, heavy metal accumulation and distribution patterns in farmland soil due to traffic activity could be different from those on plain highways. In this study, design factors including altitude, roadside distance, terrain, and tree protection were considered to analyze their influences on Cu, Zn, Cd, and Pb concentrations in farmland soils along a mountain highway around Kathmandu, Nepal. On average, the concentrations of Cu, Zn, Cd, and Pb at the sampling sites are lower than the tolerable levels. Correspondingly, pollution index analysis does not show serious roadside pollution owing to traffic emissions either. However, some maximum Zn, Cd, and Pb concentrations are close to or higher than the tolerable level, indicating that although average accumulations of heavy metals pose no hazard in the region, some spots with peak concentrations may be severely polluted. The correlation analysis indicates that either Cu or Cd content is found to be significantly correlated with Zn and Pb content while there is no significant correlation between Cu and Cd. The pattern can be reasonably explained by the vehicular heavy metal emission mechanisms, which proves the heavy metals’ homology of the traffic pollution source. Furthermore, the independent factors show complex interaction effects on heavy metal concentrations in the mountainous roadside soil, which indicate quite a different distribution pattern from previous studies focusing on urban roadside environments. It is found that the Pb concentration in the downgrade roadside soil is significantly lower than that in the upgrade soil while the Zn concentration in the

  8. Regional Tectonic Framework and Human Activities on the North Central Part of The Mexican Volcanic Belt.

    NASA Astrophysics Data System (ADS)

    Nieto-Obregon, J.

    2001-12-01

    Faults and fractures northeasterly oriented dipping NW and SE, with slips mainly normal with a slight left lateral component, affect a suite of rocks of Mesozoic to Pleistocene age, in the area of El Bajio, in the states of Queretaro, Guanajuato, Michoacan, and Aguascalientes. The faults and fractures have affected the infrastructure of the cities and surroundings of Queretaro, Celaya, Salamanca, Irapuato, Silao, Leon and Aguascalientes. In the city of Queretaro, the Tlacote-Balvanera active fault has developed a scarp and its motion may potentially affect life lines of great importance. In Celaya City a N-S trending fault traverses the city and has produced a step wise scarp more than 1.80 m high, damaging houses, streets and life lines. In Salamanca, a fault trending N 60oE, dipping to the SE extends from Cerro Gordo to the SW traversing the city and affecting with a varying degree its infrastructure. Displacements observed within the urban area reach as much as 50 cm. Close to Irapuato City, in a quarry near La Valencianita village, a N 45oE trending fault dipping to the NW affects a lacustrine sequence bearing calcareous horizons. The fault exhibits a throw of 10 m and passes north of the urban area. A similarly oriented fault traverses the city of Irapuato, and near the Traffic Circle of Puente de Guadalupe, changes its strike to the SE and continues to the city limits. In the city of Silao, a fault oriented N 60oE, traverses the city and continues to the SW up to the localities of Venta de Ramales and La Aldea. Important displacements in urban and rural areas reach more than 60 cm. Outside the city of Leon in the junction of the highways to Aguascalientes and Guadalajara a normal fault plane NE oriented and dipping SE shows striations compatible with a normal left lateral motion. Faulting is associated with old buried scarps controlled by pre existing faults, and over exploited aquifers. Some of these faults however are considered potentially active based on

  9. Belt attachment and system

    DOEpatents

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  10. Manganese formations in the accretionary belts of Japan: Implications for subduction-accretion process in an active convergent margin

    NASA Astrophysics Data System (ADS)

    Nakagawa, M.; Santosh, M.; Maruyama, S.

    2011-08-01

    In the accretionary complexes of Japan, many bedded manganese and iron-manganese ore deposits occur, especially in the Jurassic complexes such as the Chichibu, Tamba, Mino, Ashio and Northern Kitakami belts. The manganese ores in these Jurassic accretionary complexes probably formed from manganese nodule/crust-bearing siliceous sediments on deep-sea floor and were subsequently converted to the manganese ores by metamorphism during the subduction-accretion process. Some of the deposits also show the signatures of younger granitic intrusions. The manganese formations now incorporated within these belts are marker beds of accretionary tectonics associated with plate tectonic processes in convergent margins.

  11. Intense Auroral Activity (HILDCAAs) Observation as a Predictor of Radiation Belt Relativistic Electrons

    NASA Astrophysics Data System (ADS)

    Hajra, R.; Tsurutani, B.; Echer, E.

    2015-12-01

    Relativistic (E > 0.6, > 2.0, and > 4.0 MeV) electrons at geosynchronous orbit during solar cycle 23 are well-correlated with the intervals of high-intensity, long-duration, continuous AE activity (HILDCAA) events. Cluster-4 passes were examined for electromagnetic chorus waves in the 5 < L < 10 and 0 < MLT < 12 region. All the HILDCAA events under study were found to be characterized by enhanced whistler-mode chorus waves and flux enhancements of magnetospheric relativistic electrons of all three energies compared to the pre-event flux levels. CIR magnetic storms followed by HILDCAA events show almost the same relativistic electron signatures. It is concluded that the CIR storms have little to do with the acceleration of relativistic electrons. The response of the energetic electrons to HILDCAAs was found to vary with solar cycle phase. The initial electron fluxes were lower for events occurring during the ascending and solar maximum (AMAX) phases than for events occurring during the descending and solar minimum (DMIN) phases. The flux increases for the DMIN-phase events were > 50% larger than for the AMAX-phase events. It is concluded that electrons are accelerated to relativistic energies most often and most efficiently during the DMIN-phases of the solar cycle. Enhanced E > 0.6 MeV electron fluxes at geosynchronous orbit were first detected ~1 day after the statistical onset of HILDCAAs, E > 2.0 MeV electrons after ~1.5 days, and E > 4.0 MeV electrons after ~2.5 days. It is proposed that relativistic electrons are bootstrapped from high energy electrons: the E > 0.6 MeV electrons are accelerated from HILDCAA-injected E ~100 keV electrons, the E > 2.0 MeV electrons from the E > 0.6 MeV electron population, and consequently the E > 4.0 MeV electrons are accelerated from the E > 2.0 MeV population, etc. Relativistic electron acceleration and decay timescales will be provided for wave-particle investigators to attempt to match their models to empirically derived

  12. Investigating geomagnetic activity dependent sources of 100s of keV electrons in Earth's inner radiation belt using Van Allen Probes observations

    NASA Astrophysics Data System (ADS)

    Turner, D. L.; O'Brien, T. P., III; Fennell, J. F.; Claudepierre, S. G.; Blake, J. B.; Baker, D. N.; Henderson, M. G.; Reeves, G. D.

    2015-12-01

    By providing an unprecedented level of reliability in particle flux observations at low L-shells, NASA's Van Allen Probes mission has yielded a series of discoveries and unanswered questions concerning the inner electron radiation belt. Two such discoveries are: 1) a sharp cutoff in the energy distribution of electrons at ~900 keV, such that fluxes of electrons with energies greater than ~900 keV are below the detectability threshold of the Van Allen Probes' MagEIS instruments and consistent with upper flux limits of multi-MeV electrons calculated using the Van Allen Probes' REPT instruments, and 2) that impulsive injections of up to several hundred keV electrons may act as an activity-dependent source of electrons in the slot and inner radiation belt. In this presentation, we discuss results from phase space density (PSD) analysis of inner zone electrons. Such analysis, which examines PSD as a function of the three adiabatic invariants, effectively removes adiabatic variations in the particle observations allowing one to better identify source and loss processes ongoing in the system. We demonstrate that impulsive injections do indeed act as a source of inner radiation belt electrons and, when combined with losses in the slot region, can result in peaked radial distributions of electron PSD in the inner zone. We briefly discuss the nature of these low-L injections, which penetrate inside the plasmasphere and display strong energy and species dependencies. By examining such injections throughout the Van Allen Probes era, we also i) determine the occurrence rate of injections as a function of electron energy (and first adiabatic invariant), geomagnetic activity level, and L-shell; ii) estimate the contribution of such injections to the inner belt population; and iii) investigate how such injections disrupt coherent banded flux structures in the inner zone known as "zebra stripes".

  13. River Mediated Development of an Active Extensional Culmination: the Yulong Mountains, Southwestern China

    NASA Astrophysics Data System (ADS)

    Studnicki-Gizbert, C.; Whipple, K.; Burchfiel, B. C.

    2008-12-01

    The Yulong Xueshan (Jade Dragon Snow Mountains) are an isolated range of anomalously high and steep mountains bisected by the Jinsha (Yangzi) river in Western Yunnan province, in the eastern Tibetan borderlands. The range is defined and bounded by a closed network of active transtensional faults, whose most recent major rupture was a M 7.0 quake in 1997. Some of the deepest regional structural and stratigraphic levels are exposed in a domal culmination in the footwalls of these faults and at the bottom of the nearly 4km deep gorge cut by the Jinsha river. Within the gorge, the Jinsha river becomes extremely narrow and steep, suggesting adjustment to anomalously high rates of surface uplift. Geomorphic arguments suggest erosion rates of between 1 to 5 mm/yr. These rates are consistent with independently derived estimates of ~3 mm/yr based on stratigraphic and structural evidence. We argue that the anomalous exhumation and uplift rates we infer for the Yulong mountains are the result of the interaction of (1) vigorous river incision controlled erosional processes that balance rock uplift rates; (2) a closed network of normal faults that accommodate differential rock uplift rates; (3) weak middle to lower crust that flows in response to imposed surface loads. Localized uplift probably began in response to unloading along the range bounding faults, but high erosion rates are responsible for sustaining the anomalous, localized rock uplift that continues to the present. Unlike other described examples where localized exhumation along a major river is associated with a river capture event, in the Yulong mountains the closed network of normal faults permit the range to respond independently of its surroundings (and therefore have effectively no flexural strength) and accommodates localized uplift. A final key characteristic of this system is that it is superimposed upon a landscape that was already characterized by the significant incision and entrenchment of the major

  14. Polysaccharides from Umbilicaria esculenta cultivated in Huangshan Mountain and immunomodulatory activity.

    PubMed

    Du, Yi-Qun; Liu, Yong; Wang, Jun-Hui

    2015-01-01

    Umbilicaria esculenta cultivated in Huangshan Mountain (HSSE) is precious edible and medicinal lichen. In this study, four polysaccharide fractions designated as UEP1, UEP2, UEP3, and UEP4 were isolated from HSSE with water extraction at different temperature. The physico-chemical properties and immunomodulatory activities of polysaccharide fractions were investigated. The results indicated that UEP1, UEP2, UEP3 and UEP4 were acid polysaccharide with 0.50%, 0.62%, 0.63%, and 0.83% of uronic acid contents, respectively. Four polysaccharide fractions were mainly composed of glucose, galactose and mannose with different molar ratio. In the in vitro immunomodulatory assay, all the polysaccharide fractions (20-500 μg/mL) could increase the NO production and phagocytic activity of RAW 264.7 cells in a dose-dependent manner. This work demonstrated that the polysaccharides from HSSE could be used as potential biological response modifier. PMID:25316425

  15. Seismic activity triggered by the interaction of ice sheet flow with the Sør Rondane Mountains, East-Antarctica

    NASA Astrophysics Data System (ADS)

    Camelbeeck, Thierry; Lombardi, Denis; Martin, Henri; Rapagnani, Giovanni

    2015-04-01

    The interactions of the Antarctic ice sheet with the various marginal orogenic belts is poorly understood. To make up for this lack of knowledge we installed in early 2014 in the Sør Rondane Mountains of eastern Queen Maud Land, five new broadband seismic stations, in addition to an existing permanent station setting up a 90 x 30 km wide seismic network. All stations are set up to be year-round autonomously powered, all but one being on rock outcrops. Despite technical problems encountered during winter, several months of data were collected and so far about 1 month of this dataset has been processed. The background seismic noise is found to be low to extremely low with seasonal variations suggesting influence from meteorological conditions. In addition to teleseismic events, a lot of local seismicity is observed and so far 155 local quakes were detected and localized using manual picking and 2 localization methods (Hypo and NonLinLoc). The inferred locations indicate 2 major source regions for these quakes: at the border between the ice sheet and outcropping mountains and within the fastest moving ice flow suggesting that the detected seismicity is correlated with the ice flow dynamics. Further information regarding the quake focal depths and the inferred crustal model will be discussed.

  16. Evaluation of the US DOE's conceptual model of hydrothermal activity at Yucca Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Dublyansky, Y. V.

    2014-08-01

    A unique conceptual model describing the conductive heating of rocks in the thick unsaturated zone of Yucca Mountain, Nevada by a silicic pluton emplaced several kilometers away is accepted by the US Department of Energy (DOE) as an explanation of the elevated depositional temperatures measured in fluid inclusions in secondary fluorite and calcite. Acceptance of this model allowed the DOE to keep from considering hydrothermal activity in the performance assessment of the proposed high-level nuclear waste disposal facility. The evaluation presented in this paper shows that no computational modeling results have yet produced a satisfactory match with the empirical benchmark data, specifically with age and fluid inclusion data that indicate high temperatures (up to ca. 80 °C) in the unsaturated zone of Yucca Mountain. Auxiliary sub-models complementing the DOE model, as well as observations at a natural analog site, have also been evaluated. Summarily, the model cannot be considered as validated. Due to the lack of validation, the reliance on this model must be discontinued and the appropriateness of decisions which rely on this model must be re-evaluated.

  17. Yucca Mountain program summary of research and technical review activities, July 1988--June 1989

    SciTech Connect

    1989-11-01

    The Desert Research Institute (DRI), through its Water Resources Center (WRC), since 1984 has supported the State of Nevada Nuclear Waste Project Office`s activities related to the proposed high-level radioactive waste repository at Yucca Mountain on the Nevada Test Site (NTS). This effort is directed at providing the State Office with an unbiased evaluation of the Yucca Mountain Project (YMP) investigations performed by the US Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC). The overall objective is to determine independently whether or not the site meets the performance criteria defined by the Nuclear Waste Policy Act of 1982 and amendments for isolating and containing the wastes during emplacement and the proposed life of the repository. A particularly important area of concern with the proposed repository is the site`s hydrology. The faculty of the DRI have long been involved with research throughout the State and have particular expertise in groundwater studies related to radionuclide migration and hydrologic safety of underground nuclear testing by DOE and predecessor agencies. In addition, we utilize laboratory personnel for chemical and isotopic analyses in both of the DRI-WMC water chemistry laboratories.

  18. Using Digital Topography to Differentiate Erosionally Exhumed and Tectonically Active Mountains Fronts

    NASA Astrophysics Data System (ADS)

    Frankel, K. L.; Pazzaglia, F. J.

    2003-12-01

    Mountain ranges in the southern Rocky Mountains have departed on unique landscape evolutionary pathways in the late Cenozoic that are directly dependent upon the degree of post-orogenic tectonic activity they have experienced. The topography of Sierra Nacimiento, a Laramide uplift in west-central New Mexico lacking an active range-front fault, is shaped primarily by erosional exhumation that is continuous, but not steady, being driven by distal base level fall from Rio Grande incision and resultant south to north knickpoint migration. In contrast, the topography of the Taos Range, a rift flank uplift in north-central New Mexico is shaped by contrasting active stream incision and aggradation astride an active range front normal fault. The distinction between exhumation-dominated and tectonically-dominated mountain fronts is best quantified by analyses of a new metric we call the drainage basin volume to drainage basin area ratio (V-A ratio) as well as the gradients of first-order streams. Drainage basin volume and area are calculated by constructing topographic envelope maps from 10 m resolution digital elevation models (DEM). The envelope maps are pinned by the watershed divide and cover the maximum elevations in each drainage basin. Subtracting the original DEM from the maximum elevation envelope map produces a topographic residual map from which area and volume data can be obtained. The erosionally exhumed Sierra Nacimiento has a mean V-A ratio of 88 m while the tectonically active Taos Range has a mean V-A ratio of 140 m. Similarly, there are systematic differences in the gradients of first order streams measured both in the range block and approximately 5 km of adjacent piedmont. Streams were defined and subsequently Strahler ordered by a flow accumulation threshold of 250 water-equivalent grid cell units. First order stream channel long profiles were extracted from the DEM at 30 meter increments and gradients were calculated by a FORTRAN program. Gradients of

  19. The role of EUV/X-ray solar activity and electron precipitations from radiation belts in the climate changes

    NASA Astrophysics Data System (ADS)

    Avakyan, Sergey; Voronin, Nikolai; Baranova, Lubov

    The authors associate the recently observed climate warming and carbon dioxide concentration growth in lower atmospheric layers with variations of the solar-geomagnetic activity contribution to global cloud formation and with significant decrease of carbon dioxide accumulation in forests in the process of photosynthesis. The contribution of the greenhouse effect of carbon-bearing gases to global warming turns out to be insignificant. We consider the impact of microwave emissions of the ionosphere disturbed by solar flares and magnetic storms on the troposphere and suggest the radio-optical trigger mechanism of the solar influence on weather and climate of the Earth, which consists of the following three stages: - the ionosphere absorbs the ionizing solar radiation and corpuscles from the radiation belts and transforms these into microwaves through the excitation of Rydberg states by electron impact (ionospheric photoelectron, secondary and Auger electrons); - the rates of formation and destruction of water cluster ions in the troposphere are regulated by the microwave radiation; - the clusters contribute to formation of clouds, which affects the energy flux of solar radiation through the troposphere and the flux of outgoing heat from the underlying surface. All stages of the proposed mechanism were strictly confirmed: amplification of ionospheric microwave radiation during solar flares and magnetic storms was detected; the regulation of humidity at altitude above 2 km by solar microwave emission during solar flares was registered; an influence of solar flares and magnetic storms on the cloudiness is distinctly registered at least in some geographic areas; a direct influence of solar-geomagnetic activity on the global total cloud cover in latest maximum of secular variability (in 1985 - in electromagnetic solar activity, and in 2003 - in geomagnetic activity) was discovered. Basing on analysis of satellite data on global cloud cover and radiation balance the

  20. Geometry, evolution, and tectonic framework of the Skeena Fold Belt, north central British Columbia

    NASA Astrophysics Data System (ADS)

    Evenchick, Carol A.

    1991-06-01

    The Intermontane Belt of the Canadian Cordillera has long been viewed as a passive, relatively rigid block between two metamorphic-plutonic belts, the Coast Plutonic Complex and the Omineca Belt. However, the Skeena Fold Belt, which spans most of the width of the northern Intermontane Belt, exhibits shortening comparable with that in the Rocky Mountain Fold and Thrust Belt. The Skeena Fold Belt has many features of thin-skinned fold and thrust belts, such as thrust faults which sole into a detachment, a wide variety of structural styles which depend on rock type, a foreland basin which was cannibalized by continued deformation, a frontal triangle zone, and a hinterland of metamorphic and plutonic rocks (Coast Plutonic Complex). The Skeena Fold Belt thus is comparable with the Rocky Mountain Fold and Thrust Belt, but rather than deforming a continental terrace wedge, it developed in a terrane (Stikinia) which had accreted to North America in the early Mesozoic, and in Jurassic and Cretaceous clastic successions (Bowser Lake and Sustut groups) which overlie Stikinia. Structural and stratigraphic relationships show that the earliest deformation occurred between Oxfordian and Albian time and that the last folds developed in latest Cretaceous or early Tertiary time. As much as 160 km of northeastward shortening in the Skeena Fold Belt was broadly contemporaneous with crustal thickening in the Coast Plutonic Complex and Omineca Belt, with dextral strike-slip faulting east of the Skeena Fold Belt, and with shortening in the Rocky Mountain Fold and Thrust Belt. Therefore, between latest Jurassic and early Tertiary times, horizontal shortening occured across most of the width of the northern Canadian Cordillera. Concurrent shortening across the Cordillera suggests that a common detachment (or detachments) fed all of these zones as far east as the Rocky Mountain Fold and Thrust Belt.

  1. Sources and evolution of cloud-active aerosol in California's Sierra Nevada Mountains

    NASA Astrophysics Data System (ADS)

    Roberts, G. C.; Corrigan, C.; Noblitt, S.; Creamean, J.; Collins, D. B.; Cahill, J. F.; Prather, K. A.; Collett, J. L.; Henry, C.

    2011-12-01

    To assess the sources of cloud-active aerosol and their influence on the hydrological cycle in California, the CalWater Experiment took place in winter 2011 in the foothills of the Sierra Nevada Mountains. During this experiment, we coupled the capabilities of demonstrated miniaturized instrumentation - cloud condensation nuclei (CCN), water condensation nuclei (WCN) and microchip capillary electrophoresis (MCE) - to provide direct chemical measurements of cloud active aerosols. Ion concentrations of CCN droplets attribute the anthropogenic, marine and secondary organic contributions to cloud-active aerosols. Detailed spectra from an Aerosol-Time-of-Flight Mass Spectrometer provide additional information on the sources of aerosol. Storm fronts and changes in atmospheric boundary layer brought aerosol and anions associated with Central Valley pollution to the field site with CCN concentrations reaching several thousand cm-3. Hygroscopicity parameters indicate aging of the organic fraction during aerosol transport from the Central Valley to the mountains. Otherwise, CCN concentrations were low when high pressure systems prevented boundary layer development and intrusion of the Central Valley pollution to the site. MCE results show that nitrates and sulfates comprise most of the fraction of the aerosol anion mass (PM1). During the passage of storm fronts, which transported pollution from the Central Valley upslope, nitrate concentrations peaked at several μ g m-3. Low supersaturation CCN concentrations coincide with increases in aerosol nitrate, which suggests that nitrate has a role in cloud formation of giant CCN and, furthermore, in precipitation processes in the Sierra Nevada. CCN spectra show large variations depending on the aerosol sources and sometimes exhibit bi-modal distributions with minima at 0.3% Sc -- similar to the so-called 'Hoppel minima' associated to number size distributions. During these bi-modal events, sulfate also increases supporting the

  2. Determining importance and grading of items and activities for the Yucca Mountain Project

    SciTech Connect

    DeKlever, R.; Verna, B.

    1993-12-31

    Raytheon Services Nevada (RSN), in support of the Department of Energy`s (DOE) Yucca Mountain Project, has been responsible for the Title 2 designs of the initial structures, systems, and components for the Exploratory Studies Facility (ESF), and the creation of the design output documents for the Surface-Based Testing (SBT) programs. The ESF and SBT programs are major scientific contributors to the overall site characterization program which will determine the suitability of Yucca Mountain to contain a proposed High Level Nuclear Waste (HLNW) repository. Accurate, traceable and objective characterization and testing documentation that is germane to the protection of public health and safety, and the environment, and that satisfies all the requirements of 10 CFR Part 60(1), must be established, evaluated and accepted. To assure that these requirements are satisfied, specific design functions and products, including items and activities depicted within respective design output documents, are subjected to the requirements of an NRC and DOE-approved Quality Assurance (QA) program. An evaluation (classification) is applied to these items and activities to determine their importance to radiological safety (ITS) and waste isolation (ITWI). Subsequently, QA program controls are selected (grading) for the items and activities. RSN has developed a DOE-approved classification process that is based on probabilistic risk assessment (PRA) techniques and that uses accident/impact scenarios. Results from respective performance assessment and test interference evaluations are also integrated into the classification analyses for various items. The methodology and results of the RSN classification and grading processes, presented herein, relative to ESF and SBT design products, demonstrates a solid, defensible methodological basis for classification and grading.

  3. Quaternary slip-rates of the Kazerun and the Main Recent Faults: active strike-slip partitioning in the Zagros fold-and-thrust belt

    NASA Astrophysics Data System (ADS)

    Authemayou, Christine; Bellier, Olivier; Chardon, Dominique; Benedetti, Lucilla; Malekzade, Zaman; Claude, Christelle; Angeletti, Bernard; Shabanian, Esmaeil; Abbassi, Mohammad Reza

    2009-07-01

    The aim of this work is to constrain the Late Quaternary activity of two major dextral strike-slip faults of the Zagros fold-and-thrust belt of Southern Iran, within the framework of right-oblique convergence between Arabia and Eurasia. The NW-trending Main Recent fault marks the rear of the belt along two thirds of its length. Its southeastern tip connects to the northern termination of the N-trending Kazerun Fault, which affects the entire width of the belt. Horizontal slip rates have been estimated on these two faults over the last 140 ka from lateral offsets of streams and fans and in situ cosmogenic 36Cl exposure dating of cobbles sampled on the surface of these geomorphic features. Compared to GPS data, the obtained minimum slip rate of 3.5-12.5 mm yr-1 on the Main Recent Fault implies strike-slip partitioning of the convergence along this fault. Minimum slip rate of the Kazerun Fault is 2.5-4 mm yr-1 for its northern strand, 1.5-3.5 mm yr-1 for its central segment and is negligible for its southern segment. These results are consistent with southward distribution of the slip from along the Main Recent Fault to the longitudinal thrusts and folds of the fold-and-thrust belt through the Kazerun Fault, with a decrease of slip from the southeastern tip of the Main Recent Fault towards the southern termination of the Kazerun Fault. The Kazerun and associated faults form the horsetail termination of the Main Recent fault and may be seen as the propagating southeastern front of the fault system that accommodates indentation of Eurasia by Arabia.

  4. Influence of human activity patterns on epidemiology of plague in Western Usambara Mountains, Tanzania.

    PubMed

    Hubeau, Marianne; Gulinck, Hubert; Kimaro, Didas N; Hieronimo, Proches; Meliyo, Joel

    2014-07-01

    Human plague has been a recurring public health threat in some villages in the Western Usambara Mountains, Tanzania, in the period between 1980 and 2004. Despite intensive past biological and medical research, the reasons for the plague outbreaks in the same set of villages remain unknown. Plague research needs to broaden its scope and formulate new hypotheses. This study was carried out to establish relationships between the nature and the spatial extent of selected human activities on one hand, and the reported plague cases on the other hand. Three outdoor activities namely, fetching water, collecting firewood and going to the market, were selected. Through enquiries the activity patterns related to these activities were mapped in 14 villages. Standard deviation ellipses represent the extent of action spaces. Over 130 activity types were identified and listed. Of these, fetching water, collecting firewood and going to the market were used for further analysis. The results indicate a significant correlation between the plague frequency and the size of these action spaces. Different characteristics of land use and related human activities were correlated with the plague frequency at village and hamlet levels. Significant relationships were found between plague frequency and specific sources of firewood and water, and specific market places. PMID:26867274

  5. Impacts of seismic activity on long-term repository performance at Yucca Mountain

    SciTech Connect

    Gauthier, J.H.; Wilson, M.L.; Borns, D.J.; Arnold, B.W.

    1995-12-31

    Several effects of seismic activity on the release of radionuclides from a potential repository at Yucca Mountain are quantified. Future seismic events are predicted using data from the seismic hazard analysis conducted for the Exploratory Studies Facility (ESF). Phenomenological models are developed, including rockfall (thermal-mechanical and seismic) in unbackfilled emplacement drifts, container damage caused by fault displacement within the repository, and flow-path chance caused by changes in strain. Using the composite-porosity flow model (relatively large-scale, regular percolation), seismic events show little effect on total-system releases; using the weeps flow model (episodic pulses of flow in locally saturated fractures), container damage and flow-path changes cause over an order of magnitude increase in releases. In separate calculations using, more realistic representations of faulting, water-table rise caused by seismically induced changes in strain are seen to be higher than previously estimated by others, but not sufficient to reach a potential repository.

  6. Evaluation of the US DOE's conceptual model of hydrothermal activity at Yucca Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Dublyansky, Y. V.

    2012-11-01

    A unique conceptual model envisaging conductive heating of rocks in the thick unsaturated zone of Yucca Mountain, Nevada by a silicic pluton emplaced several kilometers away is accepted by the US Department of Energy (DOE) as an explanation of the elevated depositional temperatures measured in fluid inclusions in secondary fluorite and calcite. Acceptance of this model allowed the DOE not to consider hydrothermal activity in the performance assessment of the proposed high-level nuclear waste disposal facility. Evaluation shows that validation of the model by computational modeling and by observations at a natural analog site was unsuccessful. Due to the lack of validation, the reliance on this model must be discontinued and the scientific defensibility of decisions which rely on this model must be re-evaluated.

  7. Physicochemical properties and antioxidant activities of polysaccharide from floral mushroom cultivated in Huangshan Mountain.

    PubMed

    Wang, Jun-Hui; Xu, Jin-Long; Zhang, Jing-Cheng; Liu, Yong; Sun, Han-Ju; Zha, Xueqiang

    2015-10-20

    In this paper, a polysaccharide fraction (FMPS) was purified from the floral mushroom cultivated in Huangshan Mountain for the first time. Physicochemical properties and antioxidant activities of FMPS were investigated. FMPS had an average molecular weight of 7.2×10(5)Da and was composed of glucose. On the basis of FT-IR, NMR and methylation analysis, the repeating unit of FMPS was established as (1→3)-linked β-d-glucopyranosyl backbone with 1-linked β-d-glucopyranosyl branches substituted at O-6 position of (1→3)-linked β-d-glucopyranosyl residues. The advanced structure studies indicated that FMPS was a triple-helical polysaccharide. The main hydrodynamic radius (Rh) of FMPS was 23.4nm and it could form a stable system with water in 1.2×10(-2)g/mL solutions. In addition, FMPS exhibited high DPPH radical scavenging activities (79.46% at 5mg/mL) and hydroxyl radical scavenging activities (74.18% at 5mg/mL), as well as Fe(2+)chelating activities and ABTS radical scavenging activities to some extent. PMID:26256181

  8. Intracaldera volcanic activity, Toledo caldera and embayment, Jemez Mountains, New Mexico

    SciTech Connect

    Heiken, G.; Goff, F.; Stix, J.; Shafiqullah, M.; Garcia, S.; Hagan, R.

    1986-02-10

    The Toledo caldera was formed at 1.47 +- 0.06 Ma during the catastrophic eruption of the lower member, Bandelier Tuff. The caldera was obscured at 1.12 +- 0.03 Ma during eruption of the equally voluminous upper member of the Bandelier Tuff that led to formation of the Valles caldera. Earlier workers interpreted a 9-km-diameter embayment, located NE of the Valles caldera (Toledo embayment), to be a remnant of the Toledo caldera. Drill hole data and new K-Ar dates of Toledo intracaldera domes redefine the position of Toledo caldera, nearly coincident with and of the same dimensions as the younger Valles caldera. the Toledo embayment may be of tectonic origin or a small Tschicoma volcanic center caldera. This interpretation is consistent with distribution of the lower member of the Bandelier Tuff and with several other field and drilling-related observations. Explosive activity associated with Cerro Toledo Rhyolite domes is recorded in tuff deposits located between the lower and upper members of the Bandelier Tuff on the northeast flank of the Jemez Mountains. Recorded in the tuff deposits are seven cycles of explosive activity. Most cycles consists of phreatomagmatic tuffs that grade upward into Plinian pumice beds. A separate deposit, of the same age and consisting of pyroclastic surges and flows, is associated with Rabbit Mountain, located on the southeast rim of the Valles-Toledo caldera complex. These are the surface expression of what may be a thicker, more voluminous intracaldera tuff sequence. The combined deposits of the lower and upper members of the Bandelier Tuff, Toledo and Valles intracaldera sediments, tuffs, and dome lavas form what we interpret to be a wedge-shaped caldera fill. This sequence is confirmed by deep drill holes and gravity surveys.

  9. Deformational stress fields of Casper Mountain, Wyoming

    SciTech Connect

    Burfod, A.E.; Gable, D.J.

    1985-01-01

    Casper Mountain is an east-west-trending Laramide feature located immediately west of the north termination of the Laramie Mountains in central Wyoming. Precambrian rocks are exposed as its core; off-dipping Paleozoic and Mesozoic strata characterize the flanks and ends. The north side is abruptly downthrown along a major east-west fault or faults. A complex of stress fields of Precambrian and younger ages is indicated by high-angle shears and shear zones, steep-dip foliations, and multiple joint systems. One or more of the indicated Precambrian stress fields may be equivalent to that of the Cheyenne belt of the southern Laramie Mountains. In addition, at least two well-developed Laramide stress fields were active during the formation of the mountain structure. The principal maximum compressive stress of each was oriented north-south; the mean compressive axis of one was vertical whereas in the other the minimum compressive axis was vertical. Some structural features of Precambrian age, faulting in particular, appear to have influenced structures of younger ages. Prominent east-northeast-trending, high-angle faults lie approximately parallel to the Precambrian structural grain; they offset structural features of Laramide age and may be of late Laramide and/or post-Laramide age.

  10. Segmentation and kinematics of the Kazerun fault system (southern Iran): Implications for active deformation partitioning within the Zagros fold-and-thrust belt

    NASA Astrophysics Data System (ADS)

    Authemayou, C. A.; Bellier, O. B.; Chardon, D. C.; Malekzade, Z. M.; Abbassi, M. A.

    2003-04-01

    Iran is located within the interaction zone between the Arabian and Eurasian plates that currently converge at 30 mm/yr. Since the Miocene, continental collision resulted in the formation of the NW-trending Zagros fold-and-thrust belt that accommodates c.a. 10 mm/yr of NNE-trending shortening. The southeastern part of the thrust belt is affected by the north-trending, right lateral Kazerun Fault System (KFS) stretching from the Main Reverse Fault (i.e., the back-stop of the fold-and-thrust belt) in the vicinity of Borujen, in the North, to the Persian Gulf coast near Kormuj, in the south. Reconnaissance tectonic and geomorphic observations, combined with SPOT satellite image analyses allows characterising the KFS active trace geometry and kinematics as well as its relations with the folds and the thrust faults. This further allows evaluating the transfer process from right-lateral slip along the KSF to the fold-and-thrust system. The KFS consists in three North-trending fault zones of equivalent lengths (100 km) that show evidence for a northward increasing activity. The southern terminations of the fault zones are bent towards SE strikes and are generally connected westward with WNW-trending thrusts and ramp anticlines. Those terminations display a horsetail splay fault geometry associated with an eastward decrease of both the strike-slip and dip-slip component of finite offsets. Fault slip-vectors analyses indicate a consistent right-lateral strike-slip tectonic regime all along the KFS associated with a regionally homogeneous NNE-trending 1 direction. The central and northern fault zones show evidence for systematic Quaternary right-lateral offsets of geomorphic features such as stream beds and alluvial fans, as well as shutter ridges and faceted spurs. The northern termination of the KFS shows the most obvious criteria for active slip and the highest geomorphic offsets. This fault zone connects the southeastern tip of the Main Recent Fault, the major active

  11. Hypolipidemic and antioxidant activity of mountain celery (Cryptotaenia japonica Hassk) seed essential oils.

    PubMed

    Cheng, Ming-Ching; Lin, Li-Yun; Yu, Tung-Hsi; Peng, Robert Y

    2008-06-11

    Mountain celery seed essential oils (MC-E) contained 109 compounds, including mainly nine kinds of monoterpenoids, 31 kinds of of sesquiterpenoids, and 22 kinds of alcohols. A successive gel column adsorption with solvent fractionation yielded four fractionates. The pentane fractionate revealed potent hypolipidemic but poor antioxidant activities. The ether fractionate exhibited strong hypolipidemic activity in addition to excellent 1,1-diphenyl-2-picrylhydrazyl free radical- and superoxide anion-scavenging capabilities. The third acetone fractionate only showed moderate superoxide anion-scavenging activity. Finally, the fourth methanol fractionate having a rather high content of gamma-selinene, 2-methylpropanal, and Z-9-octadecenamide uniquely revealed very strong superoxide anion-scavenging capability. All MC diets except the MC-E-added diet simultaneously exhibited both significant hypolipidemic and high-density lipoprotein-cholesterol (HDL-C)-elevating capabilities. However, all diets totally failed to affect the hepatic phospholipid levels. Conclusively, the MC-E can be fractionated by such a separation technology to produce products uniquely possessing hypolipidemic and HDL-C-elevating activities. PMID:18473476

  12. Diurnal activity of Rocky Mountain elk (Cervus elaphus) and beef cattle (Bos taurus) grazing a northeastern Oregon summer range

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rocky Mountain elk (Cervus elaphus) and beef cattle (Bos taurus) exist in a complex social environment that is marked by diurnal activities such as periods of foraging, ruminating, resting, and sheltering. Elk unlike cattle, must be continually alert to potential predators. We hypothesize that elk...

  13. The upper Pleistocene on the northern face of the Guadarrama Mountains (central Spain): Palaeoclimatic phases and glacial activity

    NASA Astrophysics Data System (ADS)

    Bullón, Teresa

    2016-09-01

    The present paper provides new information on Pleistocene glacial activity in a mountainous area of the Iberian Central System. A sediment analysis associated with Pleistocene modelling was carried out using: (1) granulometric and morphometric procedures, (2) quartz grain microtexture techniques (SEM) to discriminate between glacial and no glacial origins of sediments, (3) clay X-ray diffraction study to determine intra-Pleistocene climate variability, and (4) optically stimulated luminescence (OSL) absolute dating. The results show that the sediments were formed in two different phases associated with glacial dynamics, one of them was 35-30 ky BP and another was 25-20 ky BP, separated by a short intermediate warm-wet period. Identification of glacial phenomena is new for the northern slopes of the Guadarrama Mountains (facing the north Meseta, Duero basin), although they are not unusual within the general context of the Iberian Central System. From the data provided, we deduce that glaciation in these mountains was much more intense and widespread than had previously been thought because, on the northern slopes, glaciers occupied large areas reaching the base of the mountains. The evidence favours new interpretations of Pleistocene morphology in the centre of the Iberian Peninsula and, by extension, on the southwestern edge of Europe; it also highlights the sensitivity of mountainous areas with regard to Quaternary climate changes.

  14. Waning buoyancy in the crustal roots of old mountains.

    PubMed

    Fischer, Karen M

    2002-06-27

    When mountains form through the collision of lithospheric plates, uplift of the Earth's surface is accompanied by thickening of the crust, and the buoyancy of these deep crustal roots (relative to the surrounding mantle) is thought to contribute to the support of mountain topography. Once active tectonism ceases, continuing erosion will progressively wear away surface relief. Here I provide new constraints on how crustal roots respond to erosional unloading over very long timescales. In old collisional mountain belts, ratios of surface relief to the thickness of the underlying crustal root are observed to be smaller than in young mountains. On the basis of gravity data, this trend is best explained by a decrease in the buoyancy of the crustal root with greater age since the most recent mountain-building episode which is consistent with metamorphic reactions produced by long-term cooling. An approximate balance between mountain and root mass anomalies suggests that the continental lithosphere remains weak enough to permit exhumation of crustal roots in response to surface erosion for hundreds of millions of years. The amount of such uplift, however, appears to be significantly reduced by progressive loss of root buoyancy. PMID:12087400

  15. Cytotoxic activity of Alpinia murdochii Ridl.: A mountain ginger species from Peninsular Malaysia

    PubMed Central

    Sim, Kae Shin; Ibrahim, Halijah; Malek, Sri Nurestri Abdul; Syamsir, Devi Rosmy; Awang, Khalijah

    2014-01-01

    Background: Alpinia murdochii (Zingiberaceae) is a wild ginger species restricted to mountain areas of Peninsular Malaysia. Due to rapid development and deforestation activities, this species is becoming rare. This is the first report of the cytotoxic activity of A. murdochii. Objective: The present study aimed to investigate the cytotoxic effect of leaves and rhizomes of A. murdochii against selected human cancer cell lines by using in vitro cytotoxicity assay. Materials and Methods: The leaves and rhizomes of A. murdochii were extracted in hexane, dichloromethane (CH2Cl2), and methanol (MeOH) prior to cytotoxic activity assessment against selected human cancer cell lines, namely MCF7 (hormone dependent breast carcinoma cell line), HT29 (colon carcinoma cell line), and SKOV-3 (ovarian cancer cell line) by using in vitro neutral red cytotoxicity assay. Results: The hexane and CH2Cl2 extracts of both leaves and rhizomes exhibited remarkable cytotoxic effect against SKOV-3 cells with the IC50 values in the range of 5.2-16.7 μg/ml. Conclusion: Based on the preliminary data obtained in the present study, the leaves and rhizomes of A. murdochii may be viable therapeutic or preventive candidates for the treatment of ovarian cancer. PMID:24695515

  16. Applications of radiation belt research

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Louis J.

    2011-10-01

    When Arthur Clark and John Pierce proposed geosynchronous and low-Earth-orbiting (GEO and LEO) communications satellites, respectively, they did not envision that the environment in which their concepts would fly would be anything but benign. Discovery of the Van Allen radiation belts in 1958 fundamentally altered understanding of Earth's near-space environment and its impacts on technologies. Indeed, the first commercial telecommunications satellite, Telstar 1, in LEO, failed some 6 months after launch (10 July 1962) due to trapped radiation that had been enhanced from the Starfish Prime high-altitude nuclear test on the day prior to launch. Today radiation trapped in the geomagnetic field, as well as solar energetic particles that can access the magnetosphere, forms critical constraints on the design and operations of satellite systems. These considerations were important factors in the planning of the AGU Chapman Conference on radiation belts that was hosted in July 2011 by the Memorial University of Newfoundland in St. John's, Canada (see "Chapman Conference on Radiation Belts and the Inner Magnetosphere," page 4). The conference presentations, discussions, and hallway conversations illuminated current understanding of Earth's radiation belts and critical issues remaining. Certainly, fundamental understanding of radiation belt origins remains elusive. The relative roles of adiabatic processes, geomagnetic storm injections, and wave heating, among other considerations, are central topics of intense debate and of competing modeling regimes by numerous active groups.

  17. Mountains: A Drama Exploration. ArtsEdge Curricula, Lessons and Activities.

    ERIC Educational Resources Information Center

    Bauernschub, Mary Beth

    This lesson plan for grade 3 intends for students to use creative dramatics to demonstrate an understanding of three ways a mountain can be formed; students will also explore the effects of elevation on plant and animal life and on weather in the regions on both sides of a mountain. The lesson should take two to four days to implement. It provides…

  18. Effects of Recurring Droughts on Extracellular Enzyme Activity in Mountain Grassland

    NASA Astrophysics Data System (ADS)

    Fuchslueger, L.; Bahn, M.; Kienzl, S.; Hofhansl, F.; Schnecker, J.; Richter, A.

    2015-12-01

    Water availability is a key factor for biogeochemical processes and determines microbial activity and functioning, and thereby organic matter decomposition in soils by affecting the osmotic potential, soil pore connectivity, substrate diffusion and nutrient availability. Low water availability during drought periods therefore directly affects microbial activity. Recurring drought periods likely induce shifts in microbial structure that might be reflected in altered responses of microbial turnover of organic matter by extracellular enzymes. To study this we measured a set of potential extracellular enzyme activity rates (cellobiohydrolase CBH; leucine-amino-peptidase LAP; phosphatase PHOS; phenoloxidase POX), in grassland soils that were exposed to extreme experimental droughts during the growing seasons of up to five subsequent years. During the first drought period after eight weeks of rain exclusion all measured potential enzyme activities were significantly decreased. In parallel, soil extractable organic carbon and nitrogen concentrations increased and microbial community structure, determined by phospholipid fatty acid analysis, changed. In soils that were exposed to two and three drought periods only PHOS decreased. After four years of drought again CBH, PHOS and POX decreased, while LAP was unaffected; after five years of drought PHOS and POX decreased and CBH and LAP remained stable. Thus, our results suggest that recurring extreme drought events can cause different responses of extracellular enzyme activities and that the responses change over time. We will discuss whether and to what degree these changes were related to shifts in microbial community composition. However, independent of whether a solitary or a recurrent drought was imposed, in cases when enzyme activity rates were altered during drought, they quickly recovered after rewetting. Overall, our data suggest that microbial functioning in mountain grassland is sensitive to drought, but highly

  19. In a dynamic lifting task, the relationship between cross-sectional abdominal muscle thickness and the corresponding muscle activity is affected by the combined use of a weightlifting belt and the Valsalva maneuver.

    PubMed

    Blanchard, Trevor W; Smith, Camille; Grenier, Sylvain G

    2016-06-01

    It has been shown that under isometric conditions, as the activity of the abdominal muscles increases, the thicknesses of the muscles also increase. The purpose of this experiment was to determine whether change in muscle thickness could be used as a measure of muscle activity during a deadlift as well as determining the effect of a weightlifting belt and/or the Valsalva maneuver on the muscle thicknesses. The Transversus Abdominis (TrA) and Internal Obliques (IO) muscles were analyzed at rest and during a deadlift. Muscle thickness was measured using ultrasound imaging and muscle activity was simultaneously recorded using electromyography. Each subject performed deadlift under normal conditions, while performing the Valsalva maneuver, while wearing a weightlifting belt and while both utilizing the belt and the Valsalva maneuver. There was no relationship between change in muscle thickness and muscle activity for both the TrA and IO (R(2)<0.13 for all conditions). However it was found that the Valsalva maneuver increased abdominal muscle thickness whereas the belt limited muscle expansion; each with an increase in activity. These results indicate that ultrasound cannot be used to measure muscle activity for a deadlift and that the belt affects how the IO and TrA function together. PMID:27093137

  20. 33 CFR 142.42 - Safety belts and lifelines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety belts and lifelines. 142... § 142.42 Safety belts and lifelines. (a) Except when moving from one location to another, personnel engaged in an activity where there is a hazard of falling 10 or more feet shall wear a safety belt...

  1. 33 CFR 142.42 - Safety belts and lifelines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Safety belts and lifelines. 142... § 142.42 Safety belts and lifelines. (a) Except when moving from one location to another, personnel engaged in an activity where there is a hazard of falling 10 or more feet shall wear a safety belt...

  2. 33 CFR 142.42 - Safety belts and lifelines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety belts and lifelines. 142... § 142.42 Safety belts and lifelines. (a) Except when moving from one location to another, personnel engaged in an activity where there is a hazard of falling 10 or more feet shall wear a safety belt...

  3. 33 CFR 142.42 - Safety belts and lifelines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety belts and lifelines. 142... § 142.42 Safety belts and lifelines. (a) Except when moving from one location to another, personnel engaged in an activity where there is a hazard of falling 10 or more feet shall wear a safety belt...

  4. Earthquake cluster activity beneath the Tanzawa Mountains region, Japan: Migration of hypocenters and low stress drop

    NASA Astrophysics Data System (ADS)

    Yamada, T.; Yukutake, Y.

    2013-12-01

    An earthquake cluster activity was observed beneath the Tanzawa Mountains region, Japan with a depth of 20 km in the end of January, 2012. Japan Meteorological Agency (JMA) determined hypocenters of 76 earthquakes with M > 2 in the area within 50 hours. Five of them had magnitudes greater than 4 and the largest one was 5.4. Four out of the five earthquakes had the reverse-type focal mechanisms with the P axis in the NW-SE direction. First we relocated hypocenters of the activity following the method of Yukutake et al. (2012). We estimated relative arrival times of P and S waves by calculating the coefficients of the cross correlation and relocated hypocenters with the double-difference relocation method (Waldhauser and Ellsworth, 2000). We found that the cluster activity showed a migration from the first earthquake of the activity. The parabolic migration speed was consistent with the migration speed of the deep tremor sources (Ide et al., 2010) for which the fluid activity would play an important role. We then analyzed stress drops of 17 earthquakes with M > 3.5 that occurred from January, 2000 to June, 2012 in the area of the cluster activity. We calculated empirical Green's functions from waveforms of earthquakes with magnitudes of 3.0 to 3.2 and estimated stress drops of the earthquakes assuming that the source spectra can be expressed as the omega-squared model. We found that earthquakes of the cluster activity had smaller stress drops by an order of magnitude than the values of earthquakes that occurred in the same area before the cluster activity. These results suggest that the fluid played an important role for the earthquake cluster activity. That is, the fluid increased the pore pressure, decreased the effective normal stress and triggered the cluster activity. The difference of the rupture speed and the change of the rigidity might also be candidates that account for our results. They, however, can hardly explain the results quantitatively. Fig

  5. Palaeo-pollution from mining activities in the Vosges Mountains: 1000 years and still bioavailable.

    PubMed

    Mariet, Anne-Lise; de Vaufleury, Annette; Bégeot, Carole; Walter-Simonnet, Anne-Véronique; Gimbert, Frédéric

    2016-07-01

    Mining and smelting activities have contaminated the environment with trace metals (TMs) at a worldwide scale for at least two millennia. A combination of chemical approaches and active biomonitoring was performed to analyse the environmental availability and bioavailability of TM palaeo-pollution in a former PbAg mining district in the Vosges Mountains, France. Along a soil TM contamination gradient that covered eight stations, including two archaeological mining sites, the toxicokinetics of six TMs (Pb, Cd, As, Ag, Co, Sb) in the snail Cantareus aspersus revealed that palaeo-pollution from the studied sites remains bioavailable. This study provides the first data on the accumulation kinetics of Ag and Co for C. aspersus. The environmental availability of the TMs was estimated with three chemical extraction methods (aqua regia, EDTA 50 mM, CaCl2 10 mM). Univariate regression analyses showed that EDTA extraction is the best method for estimating the bioavailability of Pb, As, Ag, Co and Sb to snails. None of the three extractants was efficient for Cd. A multivariate analysis of bioaccumulation data revealed that TM bioavailability and transfer were modulated by exposure sources (soil, humus and vegetation) rather than by soil physico-chemical characteristics. Hence, although the deposition of mining wastes dates back several centuries, these wastes still represent a source of contamination that must be considered to develop relevant site management and environmental risk assessment. PMID:27131817

  6. Air quality monitoring during building demolition activities at the Rocky Mountain Arsenal

    SciTech Connect

    Armstrong, J.A.; Ley, T.J.; Edson, H.; Edrich, J.A.; Huston, K.H.; Kutchenreiter, M.C.; Lucas, P.M.

    1997-12-31

    Rocky Mountain Arsenal (RMA) is a former production site for chemical and incendiary munitions as well as industrial chemicals, including pesticides, insecticides, and herbicides. Several contaminated areas, including former production facilities and many support buildings, currently remain on this 27-square-mile facility located just northeast of Denver, Colorado. From February 1, 1995, through June 1, 1995, a feasibility study for building demolition at RMA was conducted. This study, the Pilot Building Demolition Project (PBDP), was completed to evaluate the applicability and effectiveness of selected building remediation, emission control, and demolition techniques that may be utilized in the future during full-scale site remediation. Four buildings were demolished using a variety of strategies and techniques. The US Army conducted intensive ambient air monitoring in the vicinity of demolition activity throughout the PBDP. Monitoring was conducted for total suspended particulates (TSP), particulate matter less than 10 micrometers in diameter (PM-10), heavy metals, mercury, volatile organic compounds (VOCs), and organochlorine pesticides (OCPs). Mobile sampling platforms were placed in the four cardinal directions around each demolition area to provide intensive close-in monitoring coverage. Additional samplers, which are part of a larger, RMA-wide monitoring network, were also used to provide more distant sampling locations in the vicinity of each area. The objective of the monitoring program was to characterize the effects of demolition activities on the surrounding air quality.

  7. Active fold-thrust belts in the foreland of eastern Tibet, the Longquan and Xiongpu anticlines in Sichuan, China

    NASA Astrophysics Data System (ADS)

    Lee, Jian-Cheng; Chan, Yu-Chang; Lu, Chia-Yu; Chen, Chih-Tung; Chu, Hao-Tsu; Liu, Yuiping; Li, Jianzhong

    2016-04-01

    The 2008 M7.9 Wenchuan earthquake ruptured from the Longmenshan fault system, which is the frontal thrust system in eastern Tibet. Further east toward the foreland area in the Sichuan basin, it sits two anticlinal structures, the Longquan and Xiongpu anticlines, which trends sub-parallel to the Longmenshan range with a distance of about 70-100 km to the mountain front. It is widely considered that these two anticlinal features are attributed to propagation of the eastward extrusion of the eastern Tibetan plateau, similar to the stress system the Wenchuan earthquake. In this study, we carried out field investigations on these two active anticlinal structures in order to characterize the bulk deformation of the anticlines. We also conducted fracture analysis and fault-slip data analysis, in an attempt to characterize the fracture developments of the rock and the paleostress states related to the faulting events associated growth of the anticlines. We thus constructed a series of geological cross sections along these two anticlines. Our results show that the Longquan anticline is characterized by pop up structure with a dominant west-vergent thrust (i.e., backthrust) on the western limb. On the other hand to the eastern limb, an east-vergent thrust only well developed in the middle part of the anticline and die out toward the north and the south. For the Xiongpu anticline, it is characterized by a pre-dominant west-vergent backthrust system without developing an east-vergent thrust. A strike-slip fault and a series of N-S-trending pop-up thrusts cut across the Xiongpu anticline indicate a rather complex stress system with two dominant compression directions, NW-SE and E-W, subsequently or alternatively affected the area. Finally, the fracture analysis revealed that 2-3 pre-dominant bedding-perpendicular fracture sets are commonly developed in the massive sandstone layers. Most of them seemingly are of the characteristics of the mode I open joint, without clear

  8. Seat belt use and stress in adolescents.

    PubMed

    Schichor, A; Beck, A; Bernstein, B; Crabtree, B

    1990-01-01

    This study explored the association of adolescent seat belt use with psychosocial risk factors in an urban minority population after the enactment of a mandatory seat belt law. Data on seat belt use, family support, feelings of being down, suicidal ideation, substance abuse, sexual activity, school troubles, and problems with the law were obtained from 541 self-report intake forms administered to an adolescent medicine clinic population from 1986 to 1987. Respondents were almost exclusively black and Hispanic; 315 (59%) were females and 222 (41%) males, with a mean age of 15.4. Seat belt use was reported by 249 (46%) and no or intermittent use by 292 (54%). Chi-square and Wilcoxon rank sums tests were used to examine associations between seat belt use and risk factors. Results showed that the group comprised of those reporting no and intermittent seat belt use was significantly more likely to feel down, have decreased home support, have problems with school and the law, have been on probation, and feel that life in general was not going very well. No association was found between seat belt use and cigarette, drug, or alcohol use or sexual activity without contraceptives. Taking into account the lack of observed behavioral information to validate such self-report questionnaires, these data nevertheless point to the nonuse or intermittent use of seat belts as a possible manifestation of a lack of self-care due to feeling down and/or preoccupation with family, school, or societal problems. PMID:2275431

  9. Active layer thermal monitoring of a Dry Valley of the Ellsworth Mountains, Continental Antarctica

    NASA Astrophysics Data System (ADS)

    Schaefer, Carlos Ernesto; Michel, Roberto; Souza, Karoline; Senra, Eduardo; Bremer, Ulisses

    2015-04-01

    The Ellsworth Mountains occur along the southern edge of the Ronne-Filchner Ice Shelf and are subdivided by the Minnesota Glacier into the Heritage Range to the east and the Sentinel Range to the West. The climate of the Ellsworth Mountains is strongly controlled by proximity to the Ronne-Filchner Ice Shelf and elevation. The mean annual air temperature at the 1,000 m level is estimated to be -25°C, and the average annual accumulation of water-equivalent precipitation likely ranges from 150 to 175 mm yr-1 (Weyant, 1966). The entire area is underlain by continuous permafrost of unknown thickness. Based on data collected from 22 pits, 41% of the sites contained dry permafrost below 70 cm, 27% had ice-cemented permafrost within 70 cm of the surface, 27% had bedrock within 70 cm, and 5% contained an ice-core (Bockheim, unpublished; Schaefer et al., 2015). Dry-frozen permafrost, which may be unique to Antarctica, appears to form from sublimation of moisture in ice-cemented permafrost over time. Active-layer depths in drift sheets of the Ellsworth Mountains range from 15 to 50 cm (Bockheim, unpublished); our understanding of Antarctic permafrost is poor, especially at the continent. The active layer monitoring sites were installed at Edson Hills, Ellsworth_Mountains, in the summer of 2012, and consist of thermistors (accuracy ± 0.2 °C) installed at 1 m above ground for air temperature measurements at two soil profiles on quartzite drift deposits, arranged in a vertical array (Lithic Haplorthel 886 m asl, 5 cm, 10 cm, 30 cm and Lithic Anyorthel 850 m asl, 5 cm, 10 cm, 30 cm). All probes were connected to a Campbell Scientific CR 1000 data logger recording data at hourly intervals from January 2nd 2012 until December 29th 2013. We calculated the thawing days (TD), freezing days (FD); isothermal days (ID), freeze thaw days (FTD), thawing degree days (TDD) and freezing degree days (FDD); all according to Guglielmin et al. (2008). Temperature at 5 cm reaches a maximum

  10. Late Cenozoic transtensional fault belt discovered on the boundary of the Awati Sag in the northwestern Tarim Basin

    NASA Astrophysics Data System (ADS)

    Li, Yue-Jun; Zhang, Qiang; Zhang, Guang-Ya; Yang, Hai-Jun; Yang, Xian-Zhang; Shi, Jun; Neng, Yuan; Chen, Yan-Gui; Wen, Lei

    2015-07-01

    Late Cenozoic transtensional fault belt was discovered on Shajingzi fault belt, NW boundary of the Awati Sag in the northwestern Tarim Basin. And numerous Quaternary normal faults were discovered on Aqia and Tumuxiuke fault belts, SW boundary of Awati. This discovery reveals Quaternary normal fault activity in the Tarim Basin for the first time. It is also a new discovery in the southern flank of Tianshan Mountains. Shajingzi transtensional fault belt is made up of numerous, small normal faults. Horizontally, the normal faults are arranged in right-step, en echelon patterns along the preexisting Shajingzi basement fault, forming a sinistral transtensional normal fault belt. In profile, they cut through the Paleozoic to the mid-Quaternary and combine to form negative flower structures. The Late Cenozoic normal faults on the SW boundary of Awati Sag were distributed mainly in the uplift side of the preexisting Aqia and Tumuxiuke basement-involved faults, and combined to form small horst and graben structures in profile. Based on the intensive seismic interpretation, careful fault mapping, and growth index analysis, we conclude that the normal fault activity of Shajingzi transtensional fault belt began from Late Pliocene and ceased in Late Pleistocene (mid-Quaternary). And the normal faulting on the SW boundary of Awati Sag began from the very beginning of Quaternary and ceased in Pleistocene. The normal faulting on Awati's SW boundary began a little later than those on the NW boundary. The origin of Shajingzi transtensional normal fault belt was due to the left-lateral strike-slip occurred in the southern flank of Tianshan, and then, due to the eastward escape of the Awati block, a tensional stress developed the normal faults on its SW boundary.

  11. Ophiolites in the Xing'an-Inner Mongolia accretionary belt of the CAOB: Implications for two cycles of seafloor spreading and accretionary orogenic events

    NASA Astrophysics Data System (ADS)

    Song, Shuguang; Wang, Ming-Ming; Xu, Xin; Wang, Chao; Niu, Yaoling; Allen, Mark B.; Su, Li

    2015-10-01

    The Xing'an-Inner Mongolia accretionary belt in the southeastern segment of the Central Asian Orogenic Belt (CAOB) was produced by the long-lived subduction and eventual closure of the Paleo-Asian Ocean and by the convergence between the North China Craton and the Mongolian microcontinent. Two ophiolite belts have been recognized: the northern Erenhot-Hegenshan-Xi-Ujimqin ophiolite belt and the southern Solonker-Linxi ophiolite belt. Most basalts in the northern ophiolite belt exhibit characteristics of normal-type to enriched-type mid-ocean ridge basalt affinities with depleted Nd isotopic composition (ɛNd(t) > +5), comparable to modern Eastern Pacific mid-ocean ridge basalts. Most basaltic rocks in the southern belt show clear geochemical features of suprasubduction zone-type oceanic crust, probably formed in an arc/back-arc environment. The inferred back-arc extension along the Solonker-Linxi belt started at circa 280 Ma. Statistics of all the available age data for the ophiolites indicates two cycles of seafloor spreading/subduction, which gave rise to two main epochs of magmatic activity at 500-410 Ma and 360-220 Ma, respectively, with a gap of ~50 million years (Myr). The spatial and temporal distribution of the ophiolites and concurrent igneous rocks favor bilateral subduction toward the two continental margins in the convergence history, with final collision at ~230-220 Ma. In the whole belt, signals of continental collision and Himalayan-style mountain building are lacking. We thus conclude that the Xing'an-Inner Mongolia segment of the CAOB experienced two cycles of seafloor subduction, back-arc extension, and final "Appalachian-type" soft collision.

  12. The elevational pattern of microbial community and enzyme activity along the northern slop of Changbai Mountain

    NASA Astrophysics Data System (ADS)

    Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; Ge, Jianpin; He, Nianpeng; Wang, Qiufeng; Wang, Dan

    2014-05-01

    we present a comprehensive analysis of soil microbial community structure, enzyme activities and their role in soil organic matter mineralization along six elevations representing five typical vegetation types from forest to alpine tundra in Changbai Mountain, China. The results showed that the microbial PLFAs presented hump-shaped patterns along the elevation with the total microbial PLFAs highest in Ermans birch forest soil. The fungi to bacteria and gram positive to negative bacteria ratios increased along the elevation with the lowest values in Broad leaved forest and Dark-coniferous spruce-fir forest soil, respectively. The soil microbial community structures showed a biogeography distribution pattern in vertical direction with microbial community structures in Broad leaved forest and Mixed coniferous broad leaved forest different from other four sites. The soil enzyme activities in Broad leaved forest and Mixed coniferous broad leaved forest were significantly higher than in other four elevations. Principal component analysis (PCA) revealed substantial differences in soil microbial community composition among study sites, appeared to be driven primarily by MAT, MAP, soil temperature and content of silt & clay on the first principal component (PC1) which accounted for 87.1 % of the total sample variance. However, soil nutrients mainly responsible for the variation of soil enzyme activities. The soil organic matter mineralization rates tended to be highest in Ermans birch forest site and lowest in Dark-coniferous spruce-fir forest site and showed positive relationship with total microbial, bacterial and actinomycetes PLFAs. These findings could be used to facilitate interpretation of soil microbial community and ecological function in latitude forests ecosystem especially in volcanic forest ecosystem.

  13. Unravelling past flash flood activity in a forested mountain catchment of the Spanish Central System

    NASA Astrophysics Data System (ADS)

    Ballesteros-Cánovas, Juan A.; Rodríguez-Morata, Clara; Garófano-Gómez, Virginia; Rubiales, Juan M.; Sánchez-Salguero, Raúl; Stoffel, Markus

    2015-10-01

    Flash floods represent one of the most common natural hazards in mountain catchments, and are frequent in Mediterranean environments. As a result of the widespread lack of reliable data on past events, the understanding of their spatio-temporal occurrence and their climatic triggers remains rather limited. Here, we present a dendrogeomorphic reconstruction of past flash flood activity in the Arroyo de los Puentes stream (Sierra de Guadarrama, Spanish Central System). We analyze a total of 287 increment cores from 178 disturbed Scots pine trees (Pinus sylvestris L.) which yielded indications on 212 growth disturbances related to past flash flood impact. In combination with local archives, meteorological data, annual forest management records and highly-resolved terrestrial data (i.e., LiDAR data and aerial imagery), the dendrogeomorphic time series allowed dating 25 flash floods over the last three centuries, with a major event leaving an intense geomorphic footprint throughout the catchment in 1936. The analysis of meteorological records suggests that the rainfall thresholds of flash floods vary with the seasonality of events. Dated flash floods in the 20th century were primarily related with synoptic troughs owing to the arrival of air masses from north and west on the Iberian Peninsula during negative indices of the North Atlantic Oscillation. The results of this study contribute considerably to a better understanding of hazards related with hydrogeomorphic processes in central Spain in general and in the Sierra de Guadarrama National Park in particular.

  14. Geological and geophysical evidences of late Quaternary activity of the range-front fault along the mid-segment of the Longmen Shan thrust belt

    NASA Astrophysics Data System (ADS)

    Ren, J.; Xu, X.; Sun, X.; Tan, X.; Li, K.; Kang, W.; Liu, B.

    2011-12-01

    The Longmen Shan fault zone consists of three main Longmen Shan faults and the blind fault in the Chengdu Basin. Along the range front of the middle segment of the Longmen Shan, there is the lithological border in published geological maps. The existence and the latest active time of the range-front fault along the mid-segment of the Longmen Shan thrust belts are controversial for a long period. Petroleum seismic reflection and high-resolution shallow seismic reflection profile discovered the existence of the range-front fault and the fault offset the Quaternary strata. Based on detailed field observation, we found that there is an obvious linear feature along the mid-segment of the Longmen Shan front and the range-front fault displaced the late Quaternary fluvial terrace. Trench log indicates that a surface-rupture event occurred before ~1500a along the range-front fault. Differential GPS surveying and dating of fluvial terrace show that the range-front fault during late Quaternary underwent a vertical slip rate of bigger than 0.36mm/a, approximately equivalent to that along the main faults of the longmen Shan thrust belts, which demonstrates that the range-front fault also took an important role in accommodating the deformation of the Longmen Shan thrust zone. This study not only provides the fundamental data for seismic hazard assessment of the Chengdu Plain, but is helpful for the overall understanding of uplift mechanism of east Tibet.

  15. Bedrock geologic map of the Yucca Mountain area, Nye County, Nevada

    SciTech Connect

    Day, W.C.; Potter, C.J.; Sweetkind, D.S.; Fridrich, C.J.; Dickerson, R.P.; San Juan, C.A.; Drake, R.M. II

    1998-11-01

    Yucca Mountain, Nye County, Nevada, has been identified as a potential site for underground storage of high-level radioactive nuclear waste. Detailed bedrock geologic maps form an integral part of the site characterization program by providing the fundamental framework for research into the geologic hazards and hydrologic behavior of the mountain. This bedrock geologic map provides the geologic framework and structural setting for the area in and adjacent to the site of the potential repository. The study area comprises the northern and central parts of Yucca Mountain, located on the southern flank of the Timber Mountain-Oasis Valley caldera complex, which was the source for many of the volcanic units in the area. The Timber Mountain-Oasis Valley caldera complex is part of the Miocene southwestern Nevada volcanic field, which is within the Walker Lane belt. This tectonic belt is a northwest-striking megastructure lying between the more active Inyo-Mono and Basin-and-Range subsections o f the southwestern Great Basin.

  16. Topical anti-inflammatory activity of Eupatilin, a lipophilic flavonoid from mountain wormwood ( Artemisia umbelliformis Lam.).

    PubMed

    Giangaspero, Anna; Ponti, Cristina; Pollastro, Federica; Del Favero, Giorgia; Della Loggia, Roberto; Tubaro, Aurelia; Appendino, Giovanni; Sosa, Silvio

    2009-09-01

    Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone) is the major lipophilic flavonoid from Artemisia umbelliformis Lam. and Artemisia genipi Weber, two mountain wormwoods used for the production of the celebrated alpine liqueur genepy. The topical anti-inflammatory activity of eupatilin was investigated using the inhibition of the Croton-oil-induced dermatitis in the mouse ear as the end point. The oedematous response and the leukocyte infiltration were evaluated up to 48 h after the induction of phlogosis, comparing eupatilin with hydrocortisone and indomethacin as representatives of steroid and non-steroid anti-inflammatory drugs, respectively. At maximum development, eupatilin significantly reduced edema in a dose-dependent manner (ID(50) = 0.28 micromol/cm(2)), showing an anti-inflammatory potency comparable to that of indomethacin (ID(50) = 0.26 micromol/cm(2)) and only 1 order of magnitude lower than that of hydrocortisone (ID(50) = 0.03 micromol/cm(2)). Within 48 h, eupatilin (0.30 micromol/cm(2)) caused a global inhibition of the oedematous response (42%) higher than that of an equimolar dose of indomethacin (18%) and fully comparable to that of 0.03 micromol/cm(2) of hydrocortisone (55%). Moreover, the effect of eupatilin on the granulocytes infiltrate (32% inhibition) was similar to that of indomethacin (35% inhibition) and comparable to that of hydrocortisone (42% reduction), as confirmed by histological analysis. When our results are taken together, they show that eupatilin is endowed with potent in vivo topical anti-inflammatory activity, qualitatively similar to that of hydrocortisone and intermediate in terms of potency between those of steroid and non-steroid drugs. PMID:19663482

  17. Cenozoic stratigraphy and basin tectonics of the Andes Mountains, 20/sup 0/-28/sup 0/ south latitude

    SciTech Connect

    Jordan, T.E.; Alonso, R.N.

    1987-01-01

    Clastic sedimentary basins have evolved during the past 40 m.y. in the central Andes (lat. 20/sup 0/-28/sub 0/S) in response to shifting patterns of magmatism and deformation. The distribution of these basins and their genetic relations to uplifted areas are analogous to the basins and mountain belts of the North American Rocky Mountains during the Late Cretaceous and early Cenozoic. Petroleum exploration has focused on zones underlying the upper Cenozoic strata along the eastern margin of the Andes mountain belt. Between about 40 and 25 Ma, a nonmarine basin extended across the region that is now the Andes Mountains. Between about 25 and 10 Ma, the western part of the former basin became the site of a volcanic arc; sediment accumulation continued in the east, where marine intercalations demonstrate the low elevation of the basin. After 10 Ma, the volcanic arc remained active and locally widened, and crustal shortening caused regionally important thrust and reverse faulted ranges. During the past 10 m.y., up to 4000 m of coarse clastic debris accumulated in a foreland basin on the eastern flank of the mountains; meanwhile in the interior of the mountains, over 4,0000 m of fine-grained strata and evaporites accumulated in local depocenters. 8 figures.

  18. The relative importance of relief, hydroclimate and human activity as drivers of environmental change in mountain regions

    NASA Astrophysics Data System (ADS)

    Slaymaker, O.

    2009-04-01

    At longer, geological time scales relief is the dominant driver of environmental change and is a function of the rate of movement of global tectonic plates. At shorter, anthropocene time scales, hydroclimate and human activity vie for the role of dominant driver. It is anticipated that at future time scales human activity will become progressively more dominant. Mountain regions, representing about 20% of the terrestrial surface area of the globe, are by definition steep, high elevation regions which differ spatially in their absolute rates of change as a function of relief, hydroclimate and human activity. Global relief variations are characterized in terms of elevation and local elevation range. Superimposed on relief variations are global climate variations which are often closely correlated with relief. The question which engages greatest attention today is the extent to which environmental disturbances, whether hydroclimatic or anthropogenic, are indexed by sediment flux. In order to answer this question at global scale it is necessary to invoke a typology of mountain regions which is equally sensitive to both hydroclimatic and anthropogenic disturbances. Examples are drawn from tropical, temperate and polar mountain environments.

  19. Magma ascent pathways associated with large mountains on Io

    NASA Astrophysics Data System (ADS)

    McGovern, Patrick J.; Kirchoff, Michelle R.; White, Oliver L.; Schenk, Paul M.

    2016-07-01

    While Jupiter's moon Io is the most volcanically active body in the Solar System, the largest mountains seen on Io are created by tectonic forces rather than volcanic construction. Pervasive compression, primarily brought about by subsidence induced by sustained volcanic resurfacing, creates the mountains, but at the same time inhibits magma ascent in vertical conduits (dikes). We superpose stress solutions for subsidence, along with thermal stress, (both from the "crustal conveyor belt" process of resurfacing) in Io's lithosphere with stresses from Io mountain-sized loads (in a shallow spherical shell solution) in order to evaluate magma ascent pathways. We use stress orientation (least compressive stress horizontal) and stress gradient (compression decreasing upwards) criteria to identify ascent pathways through the lithosphere. There are several configurations for which viable ascent paths transit nearly the entire lithosphere, arriving at the base of the mountain, where magma can be transported through thrust faults or perhaps thermally eroded flank sections. The latter is consistent with observations of some Io paterae in close contact with mountains.

  20. Lateral ramps in the folded Appalachians and in overthrust belts worldwide; a fundamental element of thrust-belt architecture

    USGS Publications Warehouse

    Pohn, Howard A.

    2000-01-01

    Lateral ramps are zones where decollements change stratigraphic level along strike; they differ from frontal ramps, which are zones where decollements change stratigraphic level perpendicular to strike. In the Appalachian Mountains, the surface criteria for recognizing the subsurface presence of lateral ramps include (1) an abrupt change in wavelength or a termination of folds along strike, (2) a conspicuous change in the frequency of mapped faults or disturbed zones (extremely disrupted duplexes) at the surface, (3) long, straight river trends emerging onto the coastal plain or into the Appalachian Plateaus province, (4) major geomorphic discontinuities in the trend of the Blue Ridge province, (5) interruption of Mesozoic basins by cross-strike border faults, and (6) zones of modern and probable ancient seismic activity. Additional features related to lateral ramps include tectonic windows, cross-strike igneous intrusions, areas of giant landslides, and abrupt changes in Paleozoic sedimentation along strike. Proprietary strike-line seismic-reflection profiles cross three of the lateral ramps that were identified by using the surface criteria. The profiles confirm their presence and show their detailed nature in the subsurface. Like frontal ramps, lateral ramps are one of two possible consequences of fold-and-thrust-belt tectonics and are common elements in the Appalachian fold-and-thrust belt. A survey of other thrust belts in the United States and elsewhere strongly suggests that lateral ramps at depth can be identified by their surface effects. Lateral ramps probably are the result of thrust sheet motion caused by continued activation of ancient cratonic fracture systems. Such fractures localized the transform faults along which the continental segments adjusted during episodes of sea-floor spreading.

  1. Early Cretaceous tectono-magmatic activity and tectonic implications along the Sulu Orogenic Belt - case study of the Dashan complex

    NASA Astrophysics Data System (ADS)

    Liu, Yanghe; Liu, Junlai; Shi, Xiaoxiao; Yuan, Fengjie; Ni, Jinlong; Wu, Wenbin; Chen, Xiaoyu

    2016-04-01

    The tectonic extension of the eastern Eurasian continent during the Early Cretaceous resulted in widespread occurrence of metamorphic core complexes, wide rifts and related magmatic emplacement, among which the Dashan complex of the Jiaonan orogenic belt is a typical example. The complex is a complex massif of several types of granitic rocks. The core of the complex is composed of massive porphry-bearing biotite-hornblende granitoid without any evidence of ductile deformation. Mylonitized augen quartz monzonite and granodiorite constitute the margin of the complex. A transition zone is composed of porphyritic biotite-hornblende monzonite with weakly orientated K-feldspar phenocryst and mafic microgranular enclave. The foliations along the northwestern margin of the complex dip to NW at with dip angles of about 38°, and along the southwestern and northeastern margins to SE with dip angles of about 45°. Stretching lineations are constantly plunging WNW-ESE with pitch angles between 10° and 40°, which is consistent with the orientation of lineations in the other regions in eastern China. The granites,porphyritic monzogranite and the mafic microgranular enclaves in monzogranite are dated of ca.126Ma. The similarities in ages of crystallization of the monzogranite and its MME's implies the existence of magmatic mixing processes. Meanwhile, the mylonitized augen quartz monzonite and granodiorite along the margins of the complex possess crystallization ages of 129.8±1.1Ma and 132.7±2.8Ma, respectively. The petrographical zonation , structural characteristics and the systematical zircon U-Pb geochronology of the granitic rocks may suggest that the Dashan complex has experienced multistage emplacement under the same tectonic extension setting. In despite of the location of the complex near the Tanlu fault zone, the remarkable consistency of the orientations of stretching lineation of the Dashan complex to those from the other parts of the eastern China area implies

  2. Thick-skinned tectonics and basement control on geometry, kinematics and mechanics of fold-and-thrust belts. Insights from some cenozoic belts worldwide

    NASA Astrophysics Data System (ADS)

    Lacombe, Olivier; Bellahsen, Nicolas

    2015-04-01

    Fold-and-thrust belts (FTBs) form either in lower and upper plates at the expense of proximal parts of former passive margins during collision or within the upper plate of subduction orogens. In contrast, inner parts of mountain belts are likely made of stacked units from the distal passive margin domains that have undergone continental subduction and HP-LT metamorphism. There are increasing lines of evidence that the basement is involved in shortening in many FTBs worldwide, either pervasively (across the entire belt; tectonic inversion may even occur more forelandward than the mountain front) or mainly in their innermore domains where this basement is commonly exhumed. For thick-skinned FTBs that developed from former passive margins, the occurrence of weak mechanical layers within the proximal margin lithosphere (the middle and most of the lower crust are expectedly ductile) may explain that contractional deformation be distributed within most of the crust giving rise to basement-involved tectonic style. In contrast, because these weak crustal levels are usually lacking in distal parts of the margins as a result of thinning, these stronger lithospheric domains are more prone to localized deformation/subduction. Less understandable this way is the occurrence of thick-skinned wide domains within cold and strong interiors of upper plates of subduction zones, such as the Paleocene Laramide orogenic belt or the active Sierras Pampeanas belt. Structural, geophysical and thermochronological investigations within Cenozoic thick-skinned (or basement-involved thin-skinned) FTBs provide evidence for how the pre-orogenic and syn-orogenic deformation of the basement may control the geometry, kinematics and mechanics of FTBs. In this contribution, we examine some examples of FTBs where the basement is known to be involved in shortening and we review some aspects of the control exerted by the basement on the deformation. This control is demonstrated (1) at the scale of the

  3. Climate effect on soil enzyme activities and dissolved organic carbon in mountain calcareous soils: a soil-transplant experiment

    NASA Astrophysics Data System (ADS)

    Puissant, Jérémy; Cécillon, Lauric; Mills, Robert T. E.; Gavazov, Konstantin; Robroek, Bjorn J. M.; Spiegelberger, Thomas; Buttler, Alexandre; Brun, Jean-Jacques

    2013-04-01

    Mountain soils store huge amounts of carbon as soil organic matter (SOM) which may be highly vulnerable to the strong climate changes that mountain areas currently experience worldwide. Climate modifications are expected to impact microbial activity which could change the rate of SOM decomposition/accumulation, thereby questioning the net C source/sink character of mountain soils. To simulate future climate change expected in the 21st century in the calcareous pre-Alps, 15 blocks (30 cm deep) of undisturbed soil were taken from a mountain pasture located at 1400 m a.s.l. (Marchairuz, Jura, Switzerland) and transplanted into lysimeters at the same site (control) and at two other sites located at 1000 m a.s.l. and 600 m a.s.l. (5 replicates per site). This transplantation experiment which started in 2009 simulates a climate warming with a temperature increase of 4° C and a decreased humidity of 40 % at the lowest site. In this study, we used soil extracellular enzyme activities (EEA) as functional indicators of SOM decomposition to evaluate the effect of climate change on microbial activity and SOM dynamics along the seasons. Dissolved organic carbon (DOC) was also measured to quantify the assimilable carbon for microorganism. In autumn 2012, a first sampling step out of four (winter, spring and summer 2013) has been realized. We extracted 15 cm deep soil cores from each transplant (x15) and measured (i) DOC and (ii) the activities of nine different enzymes. Enzymes were chosen to represent the degradation of the most common classes of biogeochemical compounds in SOM. β-glucosidase, β-D-cellubiosidase, β-Xylosidase, N-acetyl-β-glucosaminidase, leucine aminopeptidase, lipase, phenoloxidase respectively represented the degradation of sugar, cellulose, hemicellulose, chitin, protein, lipid and lignin. Moreover, the fluorescein diacetate (FDA) hydrolysis was used to provide an estimate of global microbial activity and phosphatase was used to estimate phosphorus

  4. Reconnaissance and economic geology of Copper Mountain metamorphic complex, Owl Creek Mountains, Wyoming

    SciTech Connect

    Hausel, W.D.

    1983-08-01

    The Copper Mountain metamorphic complex lies within a westerly trending belt of Precambrian exposures known as the Owl Creek Mountains uplift. The metamorphic complex at Copper Mountain is part of a larger complex known as the Owl Creek Mountains greenstone belt. Until more detailed mapping and petrographic studies can be completed, the Copper Mountain area is best referred to as a complex, even though it has some characteristics of a greestone belt. At least three episodes of Precambrian deformation have affected the supracrustals, and two have disturbed the granites. The final Precambrian deformation event was preceded by a weak thermal event expressed by retrogressive metamorphism and restricted metasomatic alteration. During this event, a second phase of pegmatization was accompanied by hydrothermal solutions. During the Laramide orogeny, Copper Mountain was again modified by deformation. Laramide deformation produced complex gravity faults and keystone grabens. Uranium deposits were formed following major Laramide deformation. The genesis of these deposits is attributable to either the leaching of granites or the leaching of overlying tuffaceous sediments during the Tertiary. Production of metals and industrial minerals has been limited, although some gold, copper, silver, tungsten, beryl, feldspar, and lithium ore have been shipped from Copper Mountain. A large amount of uranium was produced from the Copper Mountain district in the 1950s.

  5. Effect of lunar phase on diurnal activity of Rocky Mountain Elk (Cervus Elaphus Nelsonii)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rocky Mountain elk (Cervus elaphus nelsonii) are important components in many ecosystems across the western US and are integral with both Native American and contemporary western culture. They are prized by hunters and are the object of countless works of art. These magnificent creatures are studi...

  6. To Belt or Not To Belt?

    ERIC Educational Resources Information Center

    Vail, Kathleen

    1999-01-01

    The National Highway Traffic Transportation Safety Administration (NHTSA) is in the midst of the first school-bus crash tests in more than 10 years. Its report is expected in June 2000, and those on both sides of the seat-belt debate are waiting to see what NHTSA will recommend on passenger restraints in large school buses. A sidebar lists sources…

  7. Magma ascent pathways associated with large mountains on Io

    NASA Astrophysics Data System (ADS)

    McGovern, P. J.; Kirchoff, M. R.; White, O. L.; Schenk, P.

    2013-12-01

    While Jupiter's moon Io is the most volcanically active body in the solar system, the largest mountains seen on Io are created by tectonic forces rather than volcanic construction. Pervasive compression, brought about by subsidence induced by sustained volcanic resurfacing and aided by thermal stress, creates the mountains, but at the same time inhibits magma ascent in vertical conduits (dikes). We superpose stress solutions for subsidence and thermal stress (from the 'crustal conveyor belt' resurfacing) in Io's lithosphere with stresses from Io mountain-sized loads (in a shallow spherical shell solution) in order to evaluate magma ascent pathways. We use stress orientation (least compressive stress horizontal) and stress gradient (compression decreasing upwards) criteria to identify ascent pathways through the lithosphere. For nominal 'conveyor belt' stress states, the ascent criteria are satisfied only in a narrow (5 km or so), roughly mid-lithosphere band. Superposed stresses from loading of a 150-km wide mountain (comparable to Boösaule Mons) on a lithosphere with thickness Te = 50 km results in a thickening of the ascent-favorable (AF) zone beneath the center of the edifice, with a total thickness of 38 km for an 18 km tall (post-flexure) edifice. Most of the thickening is upward, although some is downward. Widening the edifice to 200 km produces a 'U-shaped' AF zone, thin and depressed at r = 0 but intersecting the surface at distances of about 20 to 40 km from the center. Increasing edifice width increases the radial distance at which the AF zone intersects the surface. Thinner lithospheres create generally thinner AF zones, and U-shaped AF zones for narrower edifices. There are several configurations for which viable ascent paths transit nearly the entire lithosphere, arriving at the base of the mountain, where magma can be transported through thrust faults or perhaps thermally erode flank sections, the latter consistent with observations of paterae in

  8. Application of High Resolution Topography and Remote Sensing: Imagery to the Kinematics of Fold-and-Thrust Belts

    NASA Technical Reports Server (NTRS)

    Rubin, Charles

    1997-01-01

    This report summarizes one year of funding for NASA contract NAGW-3691, Application of High Resolution Topography and Remote Sensing: Imagery to the Kinematics of Fold-and-Thrust Belts. I never received year three from NASA. The funds were to support on going tectonic and topographic studies along the front of the central Transverse Ranges and expand the topographic studies to the north. Below are results from the first two years of actual funds that I received from NASA (see attached Federal Cash Transaction Reports). The main focus of this contract was to define and understand the major tectonic processes affecting the formation and evolution of the topography in convergent tectonic settings. The results will be used to test ongoing space-based geodetic measurements and will be compared with present-day seismicity in the central Transverse Ranges and adjacent basins. Two major factors that controls topography in active regions are (1) tectonic uplift due to fault-normal compression and (2) subsequent erosion. The central Transverse and Temblor Ranges are excellent regions for these focused topographic studies. The tectonic processes leading to the mountain building are relatively straightforward and thus are easy to model. Available evidence suggests that the topography in this region is relatively young, - 3.5 Ma or less. In addition,, erosional processes may be relatively easier to model compared to larger and more ancient mountain belts. For example, in larger mountain belts, topographic relief may cause significant orographic effects and high elevation may result in part of the topography located above snowline. Both factors complicate interpretation of erosional processes that may be controlled by elevation. Mountain ranges that are significantly older may have experienced a much wider variety of erosional or climatic conditions over their lifetime. While erosion rates have certainly not been consistent in the Transverse or Temblor ranges over its 3.5 Ma

  9. BLOOD MOUNTAIN ROADLESS AREA, GEORGIA.

    USGS Publications Warehouse

    Koeppen, Robert P.; Armstrong, Michelle K.

    1984-01-01

    A mineral-resource survey of the Blood Mountain Roadless Area, Georgia, indicates that there is little promise for the occurrence of mineral and energy resources. Natural gas may be present at great depth, perhaps 5 mi down and below the overthrust sheets of the Blue Ridge Mountains, but presently available information is not adequate to evaluate the resource potential of this commodity. Further seismic studies and exploratory drilling are needed to evaluate the gas potential of this part of the Eastern Overthrust Belt.

  10. Cenozoic intracontinental deformation of the Kopeh Dagh Belt, Northeastern Iran

    NASA Astrophysics Data System (ADS)

    Chu, Yang; Wan, Bo; Chen, Ling; Talebian, Morteza

    2016-04-01

    Compressional intracontinental orogens represent large tectonic zones far from plate boundaries. Since intracontinental mountain belts cannot be framed in the conventional plate tectonics theory, several hypotheses have been proposed to account for the formations of these mountain belts. The far-field effect of collision/subduction at plate margins is now well accepted for the origin and evolution of the intracontinental crust thickening, as exemplified by the Miocene tectonics of central Asia. In northern Iran, the Binalud-Alborz mountain belt witnessed the Triassic tectonothermal events (Cimmerian orogeny), which are interpreted as the result of the Paleotethys Ocean closure between the Eurasia and Central Iran blocks. The Kopeh Dagh Belt, located to the north of the Binalud-Alborz Belt, has experienced two significant tectonic phases: (1) Jurassic to Eocene rifting with more than 7 km of sediments; and (2) Late Eocene-Early Oligocene to Quaternary continuous compression. Due to the high seismicity, deformation associated with earthquakes has received more and more attention; however, the deformation pattern and architecture of this range remain poorly understood. Detailed field observations on the Cenozoic deformation indicate that the Kopeh Dagh Belt can be divided into a western zone and an eastern zone, separated by a series of dextral strike-slip faults, i.e. the Bakharden-Quchan Fault System. The eastern zone characterized by km-scale box-fold structures, associated with southwest-dipping reverse faults and top-to-the NE kinematics. In contrast, the western zone shows top-to-the SW kinematics, and the deformation intensifies from NE to SW. In the northern part of this zone, large-scale asymmetrical anticlines exhibit SW-directed vergence with subordinate thrusts and folds, whereas symmetrical anticlines are observed in the southern part. In regard to its tectonic feature, the Kopeh Dagh Belt is a typical Cenozoic intracontinental belt without ophiolites or

  11. Greenstone belts: Their boundaries, surrounding rock terrains and interrelationships

    NASA Technical Reports Server (NTRS)

    Percival, J. A.; Card, K. D.

    1986-01-01

    Greenstone belts are an important part of the fragmented record of crustal evolution, representing samples of the magmatic activity that formed much of the Earth's crust. Most belts developed rapidly, in less than 100 Ma, leaving large gaps in the geological record. Surrounding terrains provide information on the context of greenstone belts. The effects of tectonic setting, structural geometry and evolution, associated plutonic activity and sedimentation are discussed.

  12. Evolution and Dynamics of a Fold-Thrust Belt: The Sulaiman Range of Pakistan

    NASA Astrophysics Data System (ADS)

    Reynolds, K.; Copley, A.; Hussain, E.

    2014-12-01

    Plan-view curvature of geological structures and range-front topography has long been a recognized and debated feature of both ancient and active fold-thrust belts. As part of the largest active mountain range on Earth, much of the body of work surrounding this topic has focused on the Tibetan Plateau. A lack of published data, extremely limited geodetic coverage and difficulty of access mean there have been relatively few studies of the western part of the India-Asia collision zone, where the Himalaya curve to the southwest into the lobate fold-thrust belts of Pakistan. The widest of these, the Sulaiman Range, forms a strongly curved lobe with ~300km across-strike width. We present observations and models of the Sulaiman Range of western Pakistan that shed new light on the evolution and deformation of fold-thrust belts. Earthquake source inversions show that the seismic deformation in the range is concentrated in the thick pile of sediments overlying the underthrusting lithosphere of the Indian subcontinent. The slip vectors of the earthquakes vary in strike around the margin of the range, in tandem with the shape of the topography, suggesting that gravitational driving forces arising from the topography play an important role in governing the deformation of the region. Numerical models suggest that the active deformation, and extreme plan-view curvature of the range, are governed by the presence of weak sediments in a pre-existing basin on the underthrusting Indian plate. These sediments affect the stress-state in the over-riding mountain range and allow for the rapid propagation of the nose of the range and the development of extreme curvature and laterally-varying surface gradients.

  13. Christmas Mountains

    Atmospheric Science Data Center

    2013-04-17

    article title:  Christmas Mountains     View Larger Image ... New Brunswick. Located above image center are the Christmas Mountains, a region of old-growth forest nestled in a remote wilderness. Within ...

  14. Record of complex scoria cone eruptive activity at Red Mountain, Arizona, USA, and implications for monogenetic mafic volcanoes

    NASA Astrophysics Data System (ADS)

    Riggs, N. R.; Duffield, W. A.

    2008-12-01

    for sealing fine-grained ash beds in the cone, and a pressurized system developed. Residual heat from a dike that was emplaced as part of the magmatic activity provided heat that drove groundwater along the regional fault up into the cone. Eventually the overpressurized system exploded in a phreatic eruption that created the amphitheatre, which has subsequently been enlarged by water and wind erosion. The combined sequence of events at Red Mountain illustrates some of the complexities in monogenetic scoria cone eruptions that have received little attention to date.

  15. Basement involvement in the south-central Taiwan thrust belt

    NASA Astrophysics Data System (ADS)

    Brown, Dennis; Camanni, Giovanni; Alvarez, Joaquina; Ayala, Concepcion; Wu, Yih-Min; Hsieh, Hsien-Hsiang

    2015-04-01

    The Taiwan mountain belt is generally thought to develop above a shallow, through-going basal detachment confined to within the sedimentary cover of the Eurasian continental margin. Recently acquired surface geology, when combined with seismic tomography, earthquake hypocenter, and gravity data suggest, however, that basement is also involved in the deformation in south-central Taiwan. Since basement does not crop out in south central Taiwan, we adopt a P-wave velocity of 5.2 km/s has a proxy for the basement-cover interface and use it as a reference horizon. This interpretation is then tested as a density contrast by 3D modeling of the Bouguer anomaly data. The good fit between the two suggests that this surface provides a reasonable proxy as an interpretation for the top of the basement in what follows. The data suggests that, in the west, beneath the Coastal Plain and the Western Foothills, the mountain belt is evolving above a southward deepening level of detachment that is illuminated by sub-horizontal clusters of earthquake hypocenters located near the basement-cover interface. In much of the study area, this detachment appears to be below the depth of the basal thrust determined from geological constraints provided by the thrust system mapped at the surface. Furthermore, when viewed in a northwest-southeast orientation, the hypocenters cluster that defines the detachment appears to mimic the rugose extensional fault architecture imaged in the off shore to the west of Taiwan. This suggests that pre-existing faults on the margin, although oriented at a high angle to the convergence direction, are playing an active role in the development of thrust belt while still not being completely inverted. Eastward, the detachment at the basement-cover interface joins with an east-dipping hypocenter cluster that is interpreted to form a ramp that extends to greater than 20 km depth, into the middle crust. Above this ramp, basement rocks (P-wave > 5.2 km/s) are uplifted to

  16. Seat-belt Injuries

    PubMed Central

    Hamilton, J. B.

    1968-01-01

    The drivers and passengers of two cars which collided head-on all wore lap and diagonal seat-belts. Three of the four suffered ruptured viscera and two incurred flexion-compression fractures of the neck. A victim of a traffic accident who was wearing a seat-belt and who has superficial bruising or pain presents a difficult diagnostic problem. Visceral injury should be suspected in such cases. PMID:5697665

  17. Appalachian Mountains

    Atmospheric Science Data Center

    2014-05-15

    article title:  Appalachian Mountains     View Larger Image Multi-angle views of the Appalachian Mountains, March 6, 2000 . The true-color image at left is a ... from Lake Ontario to northern Georgia, and spanning the Appalachian Mountains. The three images to the right are also in true-color, ...

  18. Belt conveyor apparatus

    DOEpatents

    Oakley, David J.; Bogart, Rex L.

    1987-01-01

    A belt conveyor apparatus according to this invention defines a conveyance path including a first pulley and at least a second pulley. An endless belt member is adapted for continuous travel about the pulleys and comprises a lower portion which engages the pulleys and an integral upper portion adapted to receive objects therein at a first location on said conveyance path and transport the objects to a second location for discharge. The upper belt portion includes an opposed pair of longitudinally disposed crest-like members, biased towards each other in a substantially abutting relationship. The crest-like members define therebetween a continuous, normally biased closed, channel along the upper belt portion. Means are disposed at the first and second locations and operatively associated with the belt member for urging the normally biased together crest-like members apart in order to provide access to the continuous channel whereby objects can be received into, or discharged from the channel. Motors are in communication with the conveyance path for effecting the travel of the endless belt member about the conveyance path. The conveyance path can be configured to include travel through two or more elevations and one or more directional changes in order to convey objects above, below and/or around existing structures.

  19. A population of comets in the main asteroid belt.

    PubMed

    Hsieh, Henry H; Jewitt, David

    2006-04-28

    Comets are icy bodies that sublimate and become active when close to the Sun. They are believed to originate in two cold reservoirs beyond the orbit of Neptune: the Kuiper Belt (equilibrium temperatures of approximately 40 kelvin) and the Oort Cloud (approximately 10 kelvin). We present optical data showing the existence of a population of comets originating in a third reservoir: the main asteroid belt. The main-belt comets are unlike the Kuiper Belt and Oort Cloud comets in that they likely formed where they currently reside and may be collisionally activated. The existence of the main-belt comets lends new support to the idea that main-belt objects could be a major source of terrestrial water. PMID:16556801

  20. Does mountain permafrost in Mongolia control water availability?

    NASA Astrophysics Data System (ADS)

    Menzel, Lucas; Kopp, Benjamin; Munkhjargal, Munkhdavaa

    2016-04-01

    In semi-arid Mongolia, continuous and discontinuous permafrost covers wide parts of the mountains, especially in the northwest of the country. Long-term analysis of annual discharge from rivers draining the mountainous parts shows high temporal variability, with some evidence of decreasing trends, accompanied by decreased intra-annual variability. Investigations show that annual precipitation features small changes while annual air temperature significantly increased over the last decades, with warming rates clearly outranging the global average. Widespread and drastic changes in land cover through forest fires in northern Mongolia might have an additional impact on water retention and the stability of permafrost. Hence, there is concern about an increased degradation of mountain permafrost and a possible impact on river discharge and water availability. Decreased water availability from the mountains would have strong socio-economic implications for the population living in the steppe belt downstream the mountains. Therefore, a monitoring program has been conducted in northern Mongolia that aims to improve the understanding of how climate change and forest fires are influencing mountain permafrost and water resources. The study region, Sugnugur valley, is located about 100 km north of Ulaanbaatar and includes the transition belt between the steppe, the boreal zone and the alpine tundra of the Khentii Mountains. Extensive measurements of soil temperatures, soil moisture, discharge and climatic parameters have been carried out along transects which stretch across the Sugnugur river valley and include steppe, boreal forest as well as burnt forest. First results indicate that the environmental conditions show drastic changes after forest fire, with reduced water retention in the headwaters. After forest fires, changing runoff processes above the permafrost table have been observed, where water drains rapidly along preferential flow paths. This eventually leads to

  1. The biological activity of chernozems in the Central Caucasus Mountains (Terskii variant of altitudinal zonality), Kabardino-Balkaria

    NASA Astrophysics Data System (ADS)

    Gedgafova, F. V.; Uligova, T. S.; Gorobtsova, O. N.; Tembotov, R. Kh.

    2015-12-01

    Some parameters of the biological activity (humus content; activity of hydrolytic enzymes invertase, phosphatase, urease; and the intensity of carbon dioxide emission) were studied in the chernozems of agrocenoses and native biogeocenoses in the foothills of the Caucasus Mountains representing the Terskii variant of the altitudinal zonality. The statistically significant differences were revealed between the relevant characteristics of the soils of the agrocenoses and of the native biogeocenoses. The integral index of the ecological-biological state of the soils was used to estimate changes in the biological activity of the arable chernozems. The 40-60% decrease of this index in the cultivated chernozems testified to their degradation with a decrease in fertility and the disturbance of ecological functions as compared to these characteristics in the virgin chernozems.

  2. Active folding and thrusting in North Africa: A framework for a seismotectonic model of the Atlas Mountains

    NASA Astrophysics Data System (ADS)

    Meghraoui, Mustapha; Maouche, Said; Timoulali, Youssef; Bouhadad, Youcef; Bouaziz, Samir

    2013-04-01

    Large earthquakes in the Atlas Mountains of North Africa are often generated on thrust or reverse faults. For inland faults, surface ruptures and long-term active tectonics appear as a thrust escarpment and fold-related faulting visible in the field and using remote sensing images, or measured using space-borne geodesy (GPS or INSAR). For coastal faults, major uplifts of late Quaternary marine terraces and folding with steplike morphology are exposed indicating the incremental development of coastal active deformation. We have investigated the similarities and differences between different active fault-related folding along the Africa - Eurasia convergent plate boundary. These active structures are seismogenic and the striking case studies are the 1960 Agadir (Mw 5.9), the 1954 Orleansville (Mw 6.7), the 1980 El Asnam (Mw 7.3), the 1992 Gafsa (Mw 5.3), the 1999 Ain Temouchent (Mw 6.0), and the 2003 Zemmouri (Mw 6.8) earthquakes. From paleoseismic investigations the El Asnam active fold shows 0.6 to 1.0 mm/yr uplift rate. West of Algiers on the Sahel anticline, the levelling of uplifted successive coastal benches and notches document the incremental folding uplift with ~ 0.84 - 1.2 mm/yr uplift rate in the last 120-140 ka. The relatively fast folding growth during late Pleistocene and Holocene in the Atlas Mountains attests for the significance of earthquake activity and the importance of convergent movements between Africa and Eurasia in the Western Mediterranean. This work is prepared in the framework of the UNESCO (SIDA) - IGCP Project 601 "Seismotectonics and Seismic Hazards in Africa".

  3. Sinkholes, collapse structures and large landslides in an active salt dome submerged by a reservoir: The unique case of the Ambal ridge in the Karun River, Zagros Mountains, Iran

    NASA Astrophysics Data System (ADS)

    Gutiérrez, Francisco; Lizaga, Iván

    2016-02-01

    Ambal ridge, covering 4 km2, is a salt pillow of Gachsaran Formation with significant salt exposures in direct contact with the Karun River, Zagros Mountains. The highly cavernous salt dome is currently being flooded by the Gotvand Reservoir, second largest in Iran. Geomorphic evidence, including the sharp deflection of the Karun River and defeated streams indicate that Ambal is an active halokinetic structure, probably driven by erosional unloading. Around 30% of the salt dome is affected by large landslides up to ca. 50 × 106 m3 in volume. Slope oversteepening related to fluvial erosion and halokinetic rise seems to be the main controlling factor. A total of 693 sinkholes have been inventoried (170 sinkholes/km2), for which a scaling relationship has been produced. The depressions occur preferentially along a belt with a high degree of clustering. This spatial distribution is controlled by the proximity to the river, slope gradient and halite content in the bedrock. A large compound depression whose bottom lies below the normal maximum level of the reservoir will likely be flooded by water table rise forming a lake. The impoundment of the reservoir has induced peculiar collapse structures 220-280 m across, expressed by systems of arcuate fissures and scarps. Rapid subsurface salt dissolution is expected to generate and reactivate a large number of sinkholes and may reactivate landslides with a significant vertical component due to lack of basal support.

  4. The role of the Anaxagoras Mountain in the Miocene to Recent tectonic evolution of the eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Colbourne, Mark; Hall, Jeremy; Aksu, Ali; Çifçi, Günay

    2014-05-01

    The Anaximander Mountains are one of the many enigmatic structures situated along the morphologically and structurally complicated junction between the Hellenic and Cyprus Arcs, in the eastern Mediterranean. Interpretation of ~750 km of marine multi-channel seismic reflection data show that the present day Anaximander Mountains underwent several distinct phases of tectonic activity since Miocene. During the mid-late Miocene, a protracted, contractional tectonic regime produced the east-west trending, south-verging fold-thrust belt observed in the area. The Messinian was a period of relatively low tectonic activity, and is marked by the deposition of an evaporite layer. This phase lasted until the latest Miocene - earliest Pliocene, when a major erosional event associated with the Messinian salinity crisis occurred. Beginning in the early-mid Pliocene-Quaternary a transpressional and rotational tectonic regime prevailed over the area. The Anaximander Mountain (sensu stricto) and Anaximenes Mountain developed in the Pliocene-Quaternary associated with the reactivation, uplift and rotation of a linked, thick skinned pre-Messinian imbricate thrust fan. Back thrusting in the region accentuated the morphology of these mountains. The Anaxagoras Mountain differs both lithologically and morphologically from the Anaximander Mountain (sensu stricto) and the Anaximenes Mountain. It is probably developed associated with the emplacement of the ophiolitic Antalya Nappe Complex. Faulting in the Anaxagoras region is characterized by southwest striking thrust and/or oblique thrust faults. Due to the similarities in morphology between the Isparta Angle of southwestern Turkey and the Anaximander Mountains (sensu lato), it is hypothesized that the tectonic evolution of the two regions are similar in nature. The Anaximander Mountains (sensu lato) can thus be considered the offshore replication of the Isparta Angle, produced by similar mechanisms, but being of a younger age.

  5. Factors Limiting Microbial Growth and Activity at a Proposed High-Level Nuclear Repository, Yucca Mountain, Nevada

    PubMed Central

    Kieft, T. L.; Kovacik, W. P.; Ringelberg, D. B.; White, D. C.; Haldeman, D. L.; Amy, P. S.; Hersman, L. E.

    1997-01-01

    As part of the characterization of Yucca Mountain, Nev., as a potential repository for high-level nuclear waste, volcanic tuff was analyzed for microbial abundance and activity. Tuff was collected aseptically from nine sites along a tunnel in Yucca Mountain. Microbial abundance was generally low: direct microscopic cell counts were near detection limits at all sites (3.2 x 10(sup4) to 2.0 x 10(sup5) cells g(sup-1) [dry weight]); plate counts of aerobic heterotrophs ranged from 1.0 x 10(sup1) to 3.2 x 10(sup3) CFU g(sup-1) (dry weight). Phospholipid fatty acid concentrations (0.1 to 3.7 pmol g(sup-1)) also indicated low microbial biomasses; diglyceride fatty acid concentrations, indicative of dead cells, were in a similar range (0.2 to 2.3 pmol g(sup-1)). Potential microbial activity was quantified as (sup14)CO(inf2) production in microcosms containing radiolabeled substrates (glucose, acetate, and glutamic acid); amendments with water and nutrient solutions (N and P) were used to test factors potentially limiting this activity. Similarly, the potential for microbial growth and the factors limiting growth were determined by performing plate counts before and after incubating volcanic tuff samples for 24 h under various conditions: ambient moisture, water-amended, and amended with various nutrient solutions (N, P, and organic C). A high potential for microbial activity was demonstrated by high rates of substrate mineralization (as much as 70% of added organic C in 3 weeks). Water was the major limiting factor to growth and microbial activity, while amendments with N and P resulted in little further stimulation. Organic C amendments stimulated growth more than water alone. PMID:16535670

  6. Active mountain building and the distribution of core Maxillariinae species in tropical Mexico and Central America

    USGS Publications Warehouse

    Kirby, Stephen H.

    2011-01-01

    The observation that southeastern Central America is a hotspot for orchid diversity has long been known and confirmed by recent systematic studies and checklists. An analysis of the geographic and elevation distribution demonstrates that the most widespread species of “core” Maxillariinae are all adapted to life near sea level, whereas the most narrowly endemic species are largely distributed in wet highland environments. Drier, hotter lowland gaps exist between these cordilleras and evidently restrict the dispersal of the species adapted to wetter, cooler conditions. Among the recent generic realignments of “core” Maxillariinae based on molecular phylogenetics, the Camaridium clade is easily the most prominent genus in Central America and is largely restricted to the highlands of Costa Rica and Panama, indicating that this region is the ancestral home of this genus and that its dispersal limits are drier, lowland cordilleran gaps. The mountains of Costa Rica and Panama are among the geologically youngest topographic features in the Neotropics, reflecting the complex and dynamic interactions of numerous tectonic plates. From consideration of the available geological evidence, I conclude that the rapid growth of the mountain ranges in Costa Rica and Panama during the late Cenozoic times created, in turn, very rapid ranges in ecological life zones and geographic isolation in that part of the isthmus. Thus, I suggest that these recent geologic events were the primary drivers for accelerated orchid evolution in southeastern Central America.

  7. Puzzling Snowballs: Main Belt Comets

    NASA Astrophysics Data System (ADS)

    Yang, Bin; Meech, Karen

    2015-03-01

    Main belt comets (MBCs) are a class of newly discovered objects that exhibit comet-like appearances and yet are dynamically indistinguishable from ordinary main belt asteroids. The measured size and albedo of MBCs are similar to those of classical comets. At present, six MBCs have been discovered, namely 133P/Elst-Pizarro, 176P/LINEAR, 238P/Read, P/2008 R1, P/La Sagra and P/2006 VW139. The total number of active MBCs is estimated to be at the level of a few hundreds (Hsieh & Jewitt, 2006). Several explanations for the activity of MBCs have been suggested. These include impact ejection, sublimation and rotational instability. However, since renewed activity has been observed in 133P and 238P at successive perihelion passages, the most likely explanation may be a thermally-driven process - e.g sublimation of exposed surface ice. Although the proximity of MBCs to the Sun (r ~ 3 AU) makes the survival of surface ice improbable, thermal models have shown that water ice is thermally stable under a regolith layer a few meters thick. The study of MBCs has recently been complicated by the discoveries of two asteroid collisional events (P/2010 A2 (LINEAR) and (596) Scheila) in 2010, where comet-like dust coma/tail have been attributed to recent impacts. If MBCs are indeed icy, they represent the closest and the third established reservoir of comets (after the Oort cloud and the Kuiper belt). As such, they may have been an important source of water for the Earth's oceans. I will review the current state of MBC studies, present the latest observational results and discuss possible mechanisms that could produce the observed activity. I will also talk about current and future space missions that are dedicated or closely related to MBC studies.

  8. Tectonic evolution of the frontal Longmen San thrust belt

    NASA Astrophysics Data System (ADS)

    Chang, C.-P.; Xu, X.-W.; Yuan, R.-M.; Li, K.; Sun, X.-Z.; Chen, W.-S.

    2012-04-01

    The Longmen Shan thrust belt in the eastern margin of the Tibetan Plateau underwent deformation associated with the eastward growth of the Tibetan Plateau. Many geological features indicate that this range is not a typical active convergent mountain belt. Some of the features that indicated that this range is atypical are the fact that it is a young, high mountain, has a thickened crust with a very low GPS shortening rate, and has no corresponding foreland subsidence. Many geologists believe that the crustal thickening that occurred in this area is caused by ductile deformation rather than by thrust faulting or crustal shortening. This hypothesis successfully explains why the upper crust is largely uplifted although the horizontal shortening at the surface is still very small. However, some recent studies based on quantitative structural analysis and a balanced cross-section indicates that a large increase in shortening occurs near the range front, and the structural relief produced by folds and faults is also closely related to the topography of this front. These imply that upper-crustal deformation is the primary mechanism for generating uplift and topography in the foothills of Longmen Shan Range. This idea obviates the need for lower-crustal flow and inflation to produce and maintain the Longmen Shan Range. Scientists have created many different conceptions for the mode of tectonic deformation across the eastern margin of the Tibetan Plateau. However, almost all scientists agree that the eastern Tibetan Plateau has an exceptionally low mechanical strength, inherited from Mesozoic tectonics of the region. On the 12th of May 2008, Mw 7.9 Wenchuan earthquake occurred in this area provides a direct manifestation of the active crustal shortening and documents the importance of active crustal shortening in developing and supporting the Longmen Shan Range. The co-seismic surface rupture pattern of Wenchuan earthquake, involving multiple structures, is one of the most

  9. Seat Belts Pay Off. The Use of Economic Incentives and Public Education to Increase Seat Belt Use in a Community. Final Report.

    ERIC Educational Resources Information Center

    Campbell, B. J.; And Others

    A six-month campaign to increase seat belt use in Chapel Hill and Carrboro, North Carolina centered around the idea of giving out economic incentives for seat belt wearing. The approach was to stop vehicles at random and give all belted vehicle occupants a small prize and a chance for a large cash prize. Precampaign activities involve collecting…

  10. Mountaineering fatalities on Denali.

    PubMed

    McIntosh, Scott E; Campbell, Aaron D; Dow, Jennifer; Grissom, Colin K

    2008-01-01

    Mount McKinley, or Denali, is the tallest mountain in North America and attracts over 1,000 climbers annually from around the world. Since Denali is located within a national park, the National Park Service (NPS) manages mountaineering activities and attempts to maintain a balance of an adventurous experience while promoting safety. We retrospectively reviewed the fatalities on Denali from 1903 to 2006 to assist the NPS, medical personnel, and mountaineers improve safety and reduce fatalities on the mountain. Historical records and the NPS climber database were reviewed. Demographics, mechanisms, and circumstances surrounding each fatality were examined. Fatality rates and odds ratios for country of origin were calculated. From 1903 through the end of the 2006 climbing season, 96 individuals died on Denali. The fatality rate is declining and is 3.08/1,000 summit attempts. Of the 96 deaths, 92% were male, 51% occurred on the West Buttress route, and 45% were due to injuries sustained from falls. Sixty-one percent occurred on the descent and the largest number of deaths in 1 year occurred in 1992. Climbers from Asia had the highest odds of dying on the mountain. Fatalities were decreased by 53% after a NPS registration system was established in 1995. Although mountaineering remains a high-risk activity, safety on Denali is improving. Certain groups have a significantly higher chance of dying. Registration systems and screening methods provide ways to target at-risk groups and improve safety on high altitude mountains such as Denali. PMID:18331224

  11. Spatial distributing characteristics of land use in the southern slope of mid-Himalaya Mountains

    NASA Astrophysics Data System (ADS)

    Lu, Chen

    2014-12-01

    The southern slope of mid-Himalayan Mountains located in China's Qomolangma National Natural Reserve in Tibet Autonomous Region, is made up of several non-continuous valleys. The study collected the data including DEM(SRTM90m), 1/250,000 land use map(year 2000), 1/100 million vegetation types map ,satellite images of 4 typical valleys on Google Earth Planet Map. Made use of ArcGIS9.3 spatial analysis technology, analyzed into the 2 aspects— Mountain altitudinal belts and slope gradient of soil types of Qinghai-Tibet Plateau, so as to abtain the spatial distributing characteristics of farmland and grassland in the research areas. The conclusions indicates that: (1)no farmland below 2200m altitude, land use is influenced intensively by slope gradient factor in the altitude range of < 2500m; (2)it is in 2500m-3800m altitude range meanwhile on the 2 farming suitable slope gradient belts(<5°, 5-15°) that the very focus zone has got the relatively larger potential, suitability and yield of farming utilization; (3)on the 3 grazing suitable slope gradient belts(<5°,5-15°,15-35°), the respective fodder quantities of the 4 valleys has low differences. land use of the 4 valleys are intensively restricted by altitude and slope gradient factors so that cultivating and grazing activities take place widely on the farming unsuitable slope gradient belts(15-35°,>35°) and grazing unsuitable slope gradient belt(>35°), which is disadvantaged to ecological environmental protection and rational utilization of land resources.

  12. Mesozoic and early Tertiary paleostructure and sedimentology of central Wasatch Mountains, Uinta Mountains, and Uinta basin

    SciTech Connect

    Picard, M.D.; Bruhn, R.L.; Beck, S.L.

    1983-08-01

    During latest Cretaceous-Eocene time, 5,000 m (16,000 ft) of beds were deposited in central and northeast Utah. In the Late Cretaceous, sediment derived from the Sevier-Laramide thrust belt was transported to the east and southeast. Southerly paleocurrent directions in the base of the Currant Creek Formation (Maestrichtian) raise the possibility that uplift of the Uintas may have begun by then. The thrust belt continued as a major highland during the early Paleocene, and major uplift of the Uintas occurred. By the middle Paleocene there was an extensive lake which regressed during the late Paleocene as uplift of the Uintas continued. Lake Uinta reached its maximum size during the middle Eocene. Lower (early Duchesnean) and upper (Late Duchesnean) conglomeratic intervals record major episodes of uplift in the Uintas during latest Eocene. Structurally, the Wasatch Mountains are part of a marginal foreland fold and thrust belt. In the northern Wasatch Mountains, pre-Late Cretaceous thrust fault plates were folded in part of a large, ramp-anticline that is cored by allochthonous, crystalline basement . Foreland thrust belt structures in the central Wasatch Mountains were folded about the east-trending Uinta axis as the Uinta Mountains formed. Eastward movement on the Hogsback thrust during the Paleocene was transferred onto the adjacent Uinta axis and Uinta Mountains structure, causing about 20 km (12 mi) of sinistral slip in the western Uinta Mountains. A south-dipping fault ramp was located beneath the Uinta Mountains and extended to depths of 15 to 20 km (9 to 12 mi). Oblique-slip on this ramp probably resulted in about 20 km (12 mi) of crustal shortening perpendicular to the trend of the mountains.

  13. Denudation of Actively Growing Mountain Ranges in the Foreland of NE Tibet Inferred From in- Situ Produced Cosmogenic Be-10

    NASA Astrophysics Data System (ADS)

    Palumbo, L.; Hetzel, R.; Tao, M.; Li, X.

    2007-12-01

    At the northeastern edge of the Tibetan Plateau ranges bounded by active thrust faults offer the unique opportunity to study the competing effects of uplift and erosion during the early stages of mountain building. Owing to along- strike variations in relief, slope, and lithology, these ranges are an ideal target for studying the influence of topography, lithology, and active faulting on denudation. Here we report spatially-averaged erosion rates for catchments situated along two of these ranges based on Be-10 concentrations of quartz in stream sediments. The Yumu Shan and the western Long Shou Shan are about 60 km long and their overall shape as well as the presence of wind gaps illustrates their vertical-lateral growth during Plio-Quaternary thrust faulting (Hetzel et al. 2004a). Erosion rates determined so far for 20 small catchments are variable and range from 20 to 550 mm/kyr. The observed variability results from at least three factors: (1) the erosion rate in catchments exposing the same lithology is positively correlated with relief and mean slope, (2) weakly consolidated Cretaceous sediments generally erode faster than low-grade Paleozoic bedrock, and (3) the erosion rate seems to decrease from the centre of the fault-bounded ranges towards their propagating tips. As rates of thrust faulting and rock uplift in the region (600-1200 mm/kyr; Hetzel et al., 2004a, b) exceed the denudation rates, the active growth of mountains and the lateral growth of Tibet has not yet come to rest. References Hetzel, R., Tao, M., Niedermann, S., Strecker, M.R., Ivy-Ochs, S., Kubik, P.W., Gao, B. (2004a). Implications of the fault scaling law for the growth of topography: Mountain ranges in the broken foreland of NE Tibet, Terra Nova 16, 157-162. Hetzel, R., Tao, M., Stokes, S., Niedermann, S., Ivy-Ochs, S., Gao, B., Strecker, M.R., Kubik, P.W. (2004b). Late Pleistocene-Holocene slip rate of the Zhangye thrust (Qilian Shan, China) and implications for the active growth of the

  14. Primary succession of soil enzyme activity and heterotrophic microbial communities along the chronosequence of Tianshan Mountains No. 1 Glacier, China.

    PubMed

    Zeng, Jun; Wang, Xiao-Xia; Lou, Kai; Eusufzai, Moniruzzaman Khan; Zhang, Tao; Lin, Qing; Shi, Ying-Wu; Yang, Hong-Mei; Li, Zhong-Qing

    2015-02-01

    We investigated the primary successions of soil enzyme activity and heterotrophic microbial communities at the forefields of the Tianshan Mountains No. 1 Glacier by investigating soil microbial processes (microbial biomass and nitrogen mineralization), enzyme activity and community-level physiological profiling. Soils deglaciated between 1959 and 2008 (0, 5, 17, 31 and 44 years) were collected. Soils >1,500 years in age were used as a reference (alpine meadow soils). Soil enzyme activity and carbon-source utilization ability significantly increased with successional time. Amino-acid utilization rates were relatively higher in early, unvegetated soils (0 and 5 years), but carbohydrate utilization was higher in later stages (from 31 years to the reference soil). Discriminant analysis, including data on microbial processes and soil enzyme activities, revealed that newly exposed soils (0-5 years) and older soils (17-44 years) were well-separated from each other and obviously different from the reference soil. Correlation analysis revealed that soil organic carbon, was the primary factor influencing soil enzyme activity and heterotrophic microbial community succession. Redundancy analysis suggested that soil pH and available P were also affect microbial activity to a considerable degree. Our results indicated that glacier foreland soils have continued to develop over 44 years and soils were significantly affected by the geographic location of the glacier and the local topography. Soil enzyme activities and heterotrophic microbial communities were also significantly influenced by these variables. PMID:25472706

  15. Controls on the architecture of the Himalayan thrust belt, NW India

    NASA Astrophysics Data System (ADS)

    Robinson, D. M.; Paul, S. K.; Chambers, J. A.; Kohn, M. J.

    2009-12-01

    In the Himalayan-Tibetan orogen, the syntaxes at the eastern and western terminations of the orogen connect a 2400 km long thrust belt. If the two syntaxes are locked, the behavior of the thrust belt may be different in the syntaxes than in the central part of the thrust belt. In fact, recent work in the central part of the Himalayan thrust belt reveals shortening estimates of ~700-900 km while closer to the syntaxes, the amount of shortening may be nearly half that (~470 km). Thus, there should be an identifiable region where the character of the thrust belt changes from that of the syntaxes to that of the central part of the thrust belt. In the Himachal Pradesh region of NW India, a transition exists in the architecture of the thrust belt. North of the Kanga reentrant, the high mountains are close to the frontal part of the thrust belt; yet, near the Beas River, ~90 km to the east, and further east still in the Sutlej and Yamuna valleys, the high mountains of the thrust belt are located far into the hinterland. The presence or absence of the Greater Himalayan rocks at the surface appears to control this pattern: when Greater Himalayan rocks are absent at the surface, as near the town of Dharamsala, the thrust belt is very narrow (<20 km) and the high mountains are located near the front of the thrust belt; however, when Greater Himalayan rocks are present, as they are further eastward, the thrust belt is wider (>150 km) and the high mountains are located in the hinterland. The presence/absence of Greater Himalayan rocks at the surface also appears to control where focused erosion is presently occurring and, subsequently, the erosional exposure of Lesser Himalayan rocks. Three models reveal the possible kinematic roles of the Greater Himalayan rocks and its subsequent control of the architecture of the thrust belt: 1) the fault that carries Greater Himalayan rocks may tip out at depth; 2) slip on that fault may continue to the surface; 3) the fault tips out and

  16. Regional pore-fluid pressures in the active western Taiwan thrust belt: A test of the classic Hubbert-Rubey fault-weakening hypothesis

    NASA Astrophysics Data System (ADS)

    Yue, Li-Fan; Suppe, John

    2014-12-01

    We document regional pore-fluid pressures in the active Taiwan thrust belt using 55 deep boreholes to test the classic Hubbert-Rubey hypothesis that high static fluid pressures (depth normalized as λ = Pf/ρrgz) account for the extreme weakness of thrust faults, since effective friction μf∗ =μf(1 - λ) . Taiwan fluid pressures are dominated by disequilibrium compaction, showing fully compacted sediments with hydrostatic fluid pressures at shallow depths until the fluid-retention depth zFRD ≈ 3 km, below which sediments are increasingly undercompacted and overpressured. The Hubbert-Rubey fault weakening coefficient is a simple function of depth (1 - λ) ≈ 0.6zFRD/z. We map present-day and pre-erosion fluid pressures and weakening (1 - λ) regionally and show that active thrusts are too shallow relative to zFRD for the classic Hubbert-Rubey mechanism to be important, which requires z ≥ ˜4zFRD ≈ 12 km to have the required order-of-magnitude Hubbert-Rubey fault weakening of (1 - λ) ≤ ˜0.15. The best-characterized thrust is the Chelungpu fault that slipped in the 1999 (Mw = 7.6) Chi-Chi earthquake, which has a low effective friction μf∗ ≈ 0.08- 0.12 , yet lies near the base of the hydrostatic zone at depths of 1-5 km with a modest Hubbert-Rubey weakening of (1 - λ) ≈ 0.4-0.6. Overpressured Miocene and Oligocene detachments at 5-7 km depth have (1 - λ) ≈ 0.3. Therefore, other mechanisms of fault weakening are required, such as the dynamical mechanisms documented for the Chi-Chi earthquake.

  17. Active Extensional Faulting at the Southern Half-Graben Belt of the Tepic-Zacoalco Rift, Western Mexico

    NASA Astrophysics Data System (ADS)

    Rosas-Elguera, J.; Ferrari, L.; Delgado, M.; Uribe, A.; Valdivia, L.; Castillo, R.

    2003-12-01

    In the past decade much debate has centered upon the kinematics and the mechanism of continental deformation in western Mexico and the motion of the Jalisco block relative to North America. Two distinct models have been proposed. The first one suggest a NW-motion of the Jalisco block that would implies a right-lateral faulting along the Tepic-Zacoalco rift (TZR). More recently others authors have documented a N-NE extensional tectonics active since late Miocene and suggested that the continental boundaries of the Jalisco block, are older structures reactivated by plate boundary forces. Studies on the crustal seismicity and the kinematics of Quaternary faults provide another constraint on the direction of motion between the Jalisco block and North America. On November 4, 5, 6, and 7, 1995, one month after the October 09, 1995, Manzanillo earthquake (Mw = 8.0), a swarm of small events was felt in the Amatlan de Ca¤as half-graben and recorded by the regional seismic network of Comision Federal de Electricidad. The coda magnitude of the largest event was Mc = 2.5-3.6 and the events were located depth ranging from 6 to 10 km. This seismic activity provoked that people from Pie de la Cuesta and Yerbabuena villages were evacuated. After that a seismic station equipped with an analogic seismograph MEQ-800 at Pie de la Cuesta was installed for three months. During the same time, October, 1995, some houses distributed along a WNW trend in Ameca city underwent severe damages, they are. The digital elevations model of the Ameca city suggest that several structures tectonics are shorter than 2 km are present in the area. The present direction of motion of the Rivera plate relative to North America plate along Middle America Trench has been estimated between N19° E to N48° E (e.g. Bandy et al., 1996). During the October 09, 1995, subduction-related earthquake (Mw = 8.0) a GPS network recorded a SW motion of the Jalisco block which could be associated to an elastic deformation

  18. The Radiation Belt Storm Probes

    NASA Video Gallery

    The Radiation Belt Storm Probe mission (RBSP) will explore the Van Allen Radiation Belts in the Earth's magnetosphere. The charge particles in these regions can be hazardous to both spacecraft and ...

  19. Moving belt radiator development status

    NASA Technical Reports Server (NTRS)

    White, K. Alan

    1988-01-01

    Development of the Moving Belt Radiator (MBR) as an advanced space radiator concept is discussed. The ralative merits of Solid Belt (SBR), Liquid Belt (LBR), and Hybrid Belt (HBR) Radiators are described. Analytical and experimental efforts related to the dynamics of a rotating belt in microgravity are reviewed. The development of methods for transferring heat to the moving belt is discussed, and the results from several experimental investigations are summarized. Limited efforts related to the belt deployment and stowage, and to fabrication of a hybrid belt, are also discussed. Life limiting factors such as seal wear and micrometeroid resistance are identified. The results from various MBR point design studies for several power levels are compared with advanced Heat Pipe Radiator technology. MBR designs are shown to compare favorable at both 300 and 1000 K temperature levels. However, additional effort will be required to resolve critical technology issues and to demonstrate the advantage of MBR systems.

  20. Teaching Taekwondo in Physical Education: Incorporating the Color Belt System

    ERIC Educational Resources Information Center

    Oh, Hyun-Ju; Hannon, James C.; Banks, Aaron

    2006-01-01

    Taekwondo is an excellent lifetime physical activity that provides both physical and mental benefits to its participants. The color belt system may be creatively used in physical education to encourage improvement in all learning domains. This article provides information on incorporating the color belt system into physical education, and provides…

  1. Detecting young, slow-slipping active faults by geologic and multidisciplinary high-resolution geophysical investigations: A case study from the Apennine seismic belt, Italy

    NASA Astrophysics Data System (ADS)

    Improta, L.; Ferranti, L.; de Martini, P. M.; Piscitelli, S.; Bruno, P. P.; Burrato, P.; Civico, R.; Giocoli, A.; Iorio, M.; D'Addezio, G.; Maschio, L.

    2010-11-01

    The Southern Apennines range of Italy presents significant challenges for active fault detection due to the complex structural setting inherited from previous contractional tectonics, coupled to very recent (Middle Pleistocene) onset and slow slip rates of active normal faults. As shown by the Irpinia Fault, source of a M6.9 earthquake in 1980, major faults might have small cumulative deformation and subtle geomorphic expression. A multidisciplinary study including morphological-tectonic, paleoseismological, and geophysical investigations has been carried out across the extensional Monte Aquila Fault, a poorly known structure that, similarly to the Irpinia Fault, runs across a ridge and is weakly expressed at the surface by small scarps/warps. The joint application of shallow reflection profiling, seismic and electrical resistivity tomography, and physical logging of cored sediments has proved crucial for proper fault detection because performance of each technique was markedly different and very dependent on local geologic conditions. Geophysical data clearly (1) image a fault zone beneath suspected warps, (2) constrain the cumulative vertical slip to only 25-30 m, (3) delineate colluvial packages suggesting coseismic surface faulting episodes. Paleoseismological investigations document at least three deformation events during the very Late Pleistocene (<20 ka) and Holocene. The clue to surface-rupturing episodes, together with the fault dimension inferred by geological mapping and microseismicity distribution, suggest a seismogenic potential of M6.3. Our study provides the second documentation of a major active fault in southern Italy that, as the Irpinia Fault, does not bound a large intermontane basin, but it is nested within the mountain range, weakly modifying the landscape. This demonstrates that standard geomorphological approaches are insufficient to define a proper framework of active faults in this region. More in general, our applications have wide

  2. Flat-topped mountain ranges: Their global distribution and value for understanding the evolution of mountain topography

    NASA Astrophysics Data System (ADS)

    Calvet, Marc; Gunnell, Yanni; Farines, Bernard

    2015-07-01

    rock-cooling signatures, stratigraphic age-bracketing, stream channel gradient patterns, and other direct or indirect dating criteria. It follows that many portions of mountain belts undergo unsteady, nonuniform post-orogenic landscape evolution trajectories, with intermittent opportunities for relief reduction. The resulting erosion surfaces remain preserved as signatures of transient landscape evolution regimes. We find that (i) occurrences of planar topography form populations of discrete, insular landscape units, only some of which could be interpreted as fragments of a fluvially dissected, and/or tectonically fragmented, regional peneplain. (ii) The post-orogenic time required for achieving advanced stages of relief reduction is variable, ranging from 3 to 70 Ma. (iii) Partly depending on whether the adjacent sedimentary basins were over- or underfilled, some erosion surfaces may have been controlled by raised base levels and may thus have formed at high elevations; however, in many cases they were disconnected from marine base levels by rapid surface uplift, thus acquiring their elevated positions in recent time. In some cases, subcrustal processes such as asthenospheric anomalies, and/or lithospheric slab tear or breakoff, explain extremely rapid, regional post-orogenic uplift. (iv) Overall, the conditions for achieving surface preservation in steep and tectonically active terrain are predictable but also quite varied and contingent on context.

  3. The Timber Mountain magmato-thermal event: An intense widespread culmination of magmatic and hydrothermal activity at the southwestern Nevada volcanic field

    SciTech Connect

    Jackson, M.R. Jr.

    1988-05-01

    Eruption of the Rainier Mesa and Ammonia Tanks Members Timber Mountain Tuff at about 11.5 and 11.3 Ma, respectively, resulted in formation of the timber Mountain (TM) caldera; new K-Ar ages show that volcanism within and around the TM caldera continued for about 1 m.y. after collapse. Some TM age magmatic activity took place west and southeast of the TM caldera in the Beatty -- Bullfrog Hills and Shoshone Mountain areas, suggesting that volcanic activity at the TM caldera was an intense expression of an areally extensive magmatic system active from about 11.5 to 10Ma. Epithermal Au-Ag, Hg and fluorite mineralization and hydrothermal alteration are found in both within and surrounding the Timber Mountain -- Oasis Valley caldera complex. New K-Ar ages date this hydrothermal activity between about 13 and 10 Ma, largely between about 11.5 and 10 Ma, suggesting a genetic relation of hydrothermal activity to the TM magmatic system.

  4. Endocrine assessment of ovarian cycle activity in wild female mountain gorillas (Gorilla beringei beringei).

    PubMed

    Habumuremyi, Sosthene; Stephens, Colleen; Fawcett, Katie A; Deschner, Tobias; Robbins, Martha M

    2016-04-01

    Variability of fertility (i.e. number of births per female per year) has been reported in females of many primate species but only a few studies have explored the associated physiological and behavioral patterns. To investigate the proximate mechanisms of variability in fertility of wild female mountain gorillas (Gorilla beringei beringei), we quantified the occurrence of ovulation, matings, and successful pregnancies among females. We examined the profiles of immunoreactive pregnanediol-3-glucuronide (iPdG) for sixteen females (seven nulliparous and nine parous females, including one geriatric female; average sampling period for fecal sample collection and behavioral observations per female=175 days; SD=94 days, range=66-358 days) monitored by the staff of the Dian Fossey Gorilla Fund's Karisoke Research Center in Parc National des Volcans, Rwanda. We quantified ovarian cycles from iPdG profiles using an algorithm that we developed by adjusting the method of Kassam et al. (1996) to the characteristics of ovarian cycle profiles based on fecal hormone measurements. The mean length of ovarian cycles was 29±4 days (median: 28 days, N=13 cycles), similar to ovarian cycle lengths of other great apes and humans. As expected, we found that female mountain gorillas exhibit longer follicular phases (mean±SD: 21±3 days, N=13 cycles) than luteal phases (mean±SD: 8±3 days, N=13 cycles). We also found that the frequency of ovarian cycles was greater in parous females (i.e. 20 ovarian cycles across 44 periods of 28 days; 45.5%) than in nulliparous females (i.e. two ovarian cycles across 34 periods of 28 days; 6%). However, the frequency of days on which matings were observed did not differ significantly between parous and nulliparous females, nor between pregnant and non-pregnant females. Five pregnancies were detected with iPdG levels, but only three resulted in live births, indicating miscarriages of the other two. In sum, this study provides information on the underlying

  5. Architecture of orogenic belts and convergent zones in Western Ishtar Terra, Venus

    NASA Technical Reports Server (NTRS)

    Head, James W.; Vorderbruegge, R. W.; Crumpler, L. S.

    1989-01-01

    Linear mountain belts in Ishtar Terra were recognized from Pioneer-Venus topography, and later Arecibo images showed banded terrain interpreted to represent folds. Subsequent analyses showed that the mountains represented orogenic belts, and that each had somewhat different features and characteristics. Orogenic belts are regions of focused shortening and compressional deformation and thus provide evidence for the nature of such deformation, processes of crustal thickening (brittle, ductile), and processes of crustal loss. Such information is important in understanding the nature of convergent zones on Venus (underthrusting, imbrication, subduction), the implications for rates of crustal recycling, and the nature of environments of melting and petrogenesis. The basic elements of four convergent zones and orogenic belts in western Ishtar Terra are identified and examined, and then assess the architecture of these zones (the manner in which the elements are arrayed), and their relationships. The basic nomenclature of the convergent zones is shown.

  6. 300-km-long co-seismic surface rupture produced by the 2008 Mw 7.9 Wenchuan earthquake along the active Longmen Shan Thrust Belt, China

    NASA Astrophysics Data System (ADS)

    Lin, A.; Rao, G.; Yan, B.

    2012-12-01

    The magnitude (Mw) 7.9 (Ms 8.1) Wenchuan earthquake occurred on 12 May 2008 and ruptured active faults of the Longmen Shan Thrust Belt (LSTB), which marks the boundary between the eastern margin of the Tibetan Plateau and the Sichuan Basin. Although many studies of the 2008 Mw 7.9 Wenchuan earthquake have described the ground deformation features, rupture mechanism, and structural features of the seismogenic fault zone associated with this event, debate remains concerning the total length of the co-seismic surface rupture zone and whether the earthquake ruptured the Qingchuan Fault in the northeastern segment of the Longmen Shan Thrust Belt (LSTB), China. Based on our initial fieldwork carried out 2 days after the 2008 Wenchuan earthquake, we reported that the earthquake produced a ~285-km-long surface rupture zone along the LSTB, at the eastern margin of the Tibetan Plateau, dominated by thrust slip and right-lateral displacement along the central and northeastern segments of the zone, and by left-lateral displacement along the southeastern segment (Lin et al., 2009, 2010). However, other field-based studies have reported that the total length of the co-seismic surface rupture zone is 200-240 km and that the Qingchuan Fault was not ruptured by the Wenchuan earthquake (e.g., Liu-Zeng et al., 2009; Xu et al., 2009; Yin, 2010; Zhang et al., 2010). The length of surface rupture produced by large, individual earthquakes is a key parameter in assessing the seismic moment, the rupture mechanism, the degree of seismic hazard, and the activity of a seismogenic fault, including the recurrence interval of large earthquakes and the long-term slip rate. Therefore, additional work is needed to constrain the length of the co-seismic surface rupture and the location of rupture termination at the northeastern segment of the LSTB, in order to accurately assess the nature of the seismic hazard in the densely populated Sichuan region of China. In this study, we present new field

  7. Digital mountains: toward development and environment protection in mountain regions

    NASA Astrophysics Data System (ADS)

    Jiang, Xiaobo

    2007-06-01

    Former studies on mountain system are focused on the department or subject characters, i.e. different department and branches of learning carry out researches only for their individual purposes and with individual characters of the subject of interests. As a whole, their investigation is lacking of comprehensive study in combination with global environment. Ecological environment in mountain regions is vulnerable to the disturbance of human activities. Therefore, it is a key issue to coordinate economic development and environment protection in mountain regions. On the other hand, a lot of work is ongoing on mountain sciences, especially depending on the application of RS and GIS. Moreover, the development of the Digital Earth (DE) provides a clue to re-understand mountains. These are the background of the emergence of the Digital Mountains (DM). One of the purposes of the DM is integrating spatial related data and information about mountains. Moreover, the DM is a viewpoint and methodology of understanding and quantifying mountains holistically. The concept of the DM is that, the spatial and temporal data related to mountain regions are stored and managed in computers; moreover, manipulating, analyzing, modeling, simulating and sharing of the mountain information are implemented by utilizing technologies of RS, GIS, GPS, Geo-informatic Tupu, computer, virtual reality (VR), 3D simulation, massive storage, mutual operation and network communication. The DM aims at advancing mountain sciences and sustainable mountain development. The DM is used to providing information and method for coordinating the mountain regions development and environment protection. The fundamental work of the DM is the design of the scientific architecture. Furthermore, construct and develop massive databases of mountains are the important steps these days.

  8. Multi-phase inversion tectonics related to the Hendijan-Nowrooz-Khafji Fault activity, Zagros Mountains, SW Iran

    NASA Astrophysics Data System (ADS)

    Kazem Shiroodi, Sadjad; Ghafoori, Mohammad; Faghih, Ali; Ghanadian, Mostafa; Lashkaripour, Gholamreza; Hafezi Moghadas, Naser

    2015-11-01

    Distinctive characteristics of inverted structures make them important criteria for the identification of certain structural styles of folded belts. The interpretation of 3D seismic reflection and well data sheds new light on the structural evolution and age of inverted structures associated to the Hendijan-Nowrooz-Khafji Fault within the Persian Gulf Basin and northeastern margin of Afro-Arabian plate. Analysis of thickness variations of growth strata using "T-Z plot" (thickness versus throw plot) method revealed the kinematics of the fault. Obtained results show that the fault has experienced a multi-phase evolutionary history over six different extension and compression deformation events (i.e. positive and negative inversion) between 252.2 and 11.62 Ma. This cyclic activity of the growth fault was resulted from alteration of sedimentary processes during continuous fault slip. The structural development of the study area both during positive and negative inversion geometry styles was ultimately controlled by the relative motion between the Afro-Arabian and Central-Iranian plates.

  9. Subway construction activity influence on polycyclic aromatic hydrocarbons in fine particles: Comparison with a background mountainous site

    NASA Astrophysics Data System (ADS)

    Kong, Shaofei; Li, Xuxu; Li, Qi; Yin, Yan; Li, Li; Chen, Kui; Liu, Dantong; Yuan, Liang; Pang, Xiaobing

    2015-07-01

    Intensive construction activities worsened the surrounding atmospheric environment in China. Eighteen polycyclic aromatic hydrocarbons (PAHs) in fine particles (PM2.5) were collected at a subway construction site (SC) of Nanjing and compared with a regional background mountainous site (BM) to examine the influence of anthropogenic activities on concentrations, sources and health risks of PAHs. Average PAH concentrations at SC were higher than BM at a factor of about 5.9. All PAH species at SC were higher than BM, with the SC/BM ratios ranging from 1.3 (NaP) to 10.3 (BaP). PAH profiles differed for the two sites. The SC site had higher mass fractions of PAHs from coal combustion and vehicle emission, while the BM site held higher mass percentages of PAHs from long-range transported wood combustion and industrial activities. Lower temperature at BM may lead to the higher mass percentages of low ring PAHs. Coal combustion, traffic emissions and biomass burning were the common sources for PAHs at both SC and BM. Construction workers were exposed to higher BaPeq concentrations, nearly ten times of the background site and their lifetime cancer risk reached to 0.6 per 1,000,000 exposed worker, owing to the influence of coal combustion, vehicle emission and industrial activities at the surroundings of SC.

  10. Large-scale geometry of Montana thrust belt

    SciTech Connect

    Sears, J.W.; Dolberg, D.M.

    1986-08-01

    Regional plunge of a structural culmination in the Sawtooth Mountains, combined with seismic profiles and borehole data, show that the imbricated faults of the Montana Disturbed belt gather upward to merge into a duplex beneath a large thrust plate dominated by the Precambrian Belt Supergroup. The duplex formed after deposition of the Paleocene St. Mary River Formation. This thrust plate overlies the Lewis, Hoadley, El dorado, Steinbach, and related thrust faults and forms the main ranges of the Montana Rocky Mountains. The plate is shaped like a northeasterly tapering wedge; it is 3 to 4 km (10,000 to 13,000 ft) thick at its leading edge, but thickens to more than 25 km (15 mi) to the southwest. At its leading edge, the plate carries lower parts of the Belt supergroup, including the Greyson, Empire, and Spokane formations. These units and overlying parts of the Belt Supergroup thicken dramatically westward within the plate, and the older, very thick, metamorphosed Prichard Formation emerges along the Purcell and related anticlinoria. The plate forms a south-facing monocline along the Lewis and Clark line. The monocline is corrugated into a series of southeast-plunging en echelon folds of Late Cretaceous age and merges with the southern terminus of the Purcell anticlinorium. Along these folds, metamorphosed Belt strata of the plate plunge systematically beneath Paleozoic and Mesozoic rocks that are preserved in a regional structural depression at the foot of the monocline. Geometric constructions based on areal geology suggest that the monocline has 25 km (15 mi) of structural relief and overlies a major footwall ramp that continues northward beneath the Purcell anticlinorium. This footwall ramp corresponds to the depositional locus for the easterly tapering belt strata of the plate, suggesting a total northeasterly displacement of about 50 km (30 mi) for the plate.

  11. Non-cylindrical fold growth in the Zagros fold and thrust belt (Kurdistan, NE-Iraq)

    NASA Astrophysics Data System (ADS)

    Bartl, Nikolaus; Bretis, Bernhard; Grasemann, Bernhard; Lockhart, Duncan

    2010-05-01

    The Zagros mountains extends over 1800 km from Kurdistan in N-Iraq to the Strait of Hormuz in Iran and is one of the world most promising regions for the future hydrocarbon exploration. The Zagros Mountains started to form as a result of the collision between the Eurasian and Arabian Plates, whose convergence began in the Late Cretaceous as part of the Alpine-Himalayan orogenic system. Geodetic and seismological data document that both plates are still converging and that the fold and thrust belt of the Zagros is actively growing. Extensive hydrocarbon exploration mainly focuses on the antiforms of this fold and thrust belt and therefore the growth history of the folds is of great importance. This work investigates by means of structural field work and quantitative geomorphological techniques the progressive fold growth of the Permam, Bana Bawi- and Safeen- Anticlines located in the NE of the city of Erbil in the Kurdistan region of Northern Iraq. This part of the Zagros fold and thrust belt belongs to the so-called Simply Folded Belt, which is dominated by gentle to open folding. Faults or fault related folds have only minor importance. The mechanical anisotropy of the formations consisting of a succession of relatively competent (massive dolomite and limestone) and incompetent (claystone and siltstone) sediments essentially controls the deformation pattern with open to gentle parallel folding of the competent layers and flexural flow folding of the incompetent layers. The characteristic wavelength of the fold trains is around 10 km. Due to faster erosion of the softer rock layers in the folded sequence, the more competent lithologies form sharp ridges with steeply sloping sides along the eroded flanks of the anticlines. Using an ASTER digital elevation model in combination with geological field data we quantified 250 drainage basins along the different limbs of the subcylindrical Permam, Bana Bawi- and Safeen- Anticlines. Geomorphological indices of the drainage

  12. Responses of Fraxinus excelsior L. seedlings to ambient ozone exposure in urban and mountain areas based on physiological characteristics and antioxidant activity.

    PubMed

    Parvanova, Petya; Tzvetkova, Nikolina; Bratanova-Doncheva, Svetla; Chipev, Nesho; Fikova, Radka; Donev, Evgeni

    2013-07-01

    Effects of ozone on the sensitive tree species Fraxinus excelsior L. exposed to ambient air were investigated. The dynamics of photosynthesis, transpiration, stomatal conductance and the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in three-year-old ash seedlings were studied during a four-month period (June-September). Seedlings were exposed to ambient ozone in an urban (the Central City Park of Sofia - Borisova Gradina) and a mountain (Plana Mountain) area in Bulgaria. The sites were located near climate monitoring stations, providing data on ozone concentrations and meteorological parameters. Ozone exposure at the mountain site (AOT40) was more than two times higher compared to the urban site. Significantly higher values of sun radiation, transpiration, stomatal conductance and enzyme activity at the mountain site were also observed. At the urban site higher values of temperature and air humidity were registered. Effects of the measured variables on ash seedlings were complex and interdependent. No direct effect of ozone concentration in ambient air on the leaf physiology and biochemistry could be proved. However, intensified SOD and CAT activity in the presence of elevated ozone suggested antioxidant reaction in response to ozone uptake. PMID:23760537

  13. Deconstructing the conveyor belt.

    PubMed

    Lozier, M Susan

    2010-06-18

    For the past several decades, oceanographers have embraced the dominant paradigm that the ocean's meridional overturning circulation operates like a conveyor belt, transporting cold waters equatorward at depth and warm waters poleward at the surface. Within this paradigm, the conveyor, driven by changes in deepwater production at high latitudes, moves deep waters and their attendant properties continuously along western boundary currents and returns surface waters unimpeded to deepwater formation sites. A number of studies conducted over the past few years have challenged this paradigm by revealing the vital role of the ocean's eddy and wind fields in establishing the structure and variability of the ocean's overturning. Here, we review those studies and discuss how they have collectively changed our view of the simple conveyor-belt model. PMID:20558705

  14. Metamorphic belts of Anatolia

    NASA Astrophysics Data System (ADS)

    Oberhänsli, Roland; Prouteau, Amaury; Candan, Osman; Bousquet, Romain

    2015-04-01

    Investigating metamorphic rocks from high-pressure/low-temperature (HP/LT) belts that formed during the closure of several oceanic branches, building up the present Anatolia continental micro-plate gives insight to the palaeogeography of the Neotethys Ocean in Anatolia. Two coherent HP/LT metamorphic belts, the Tavşanlı Zone (distal Gondwana margin) and the Ören-Afyon-Bolkardağ Zone (proximal Gondwana margin), parallel their non-metamorphosed equivalent (the Tauride Carbonate Platform) from the Aegean coast in NW Anatolia to southern Central Anatolia. P-T conditions and timing of metamorphism in the Ören-Afyon-Bolkardağ Zone (>70?-65 Ma; 0.8-1.2 GPa/330-420°C) contrast those published for the overlying Tavşanlı Zone (88-78 Ma; 2.4 GPa/500 °C). These belts trace the southern Neotethys suture connecting the Vardar suture in the Hellenides to the Inner Tauride suture along the southern border of the Kirşehir Complex in Central Anatolia. Eastwards, these belts are capped by the Oligo-Miocene Sivas Basin. Another HP/LT metamorphic belt, in the Alanya and Bitlis regions, outlines the southern flank of the Tauride Carbonate Platform. In the Alanya Nappes, south of the Taurides, eclogites and blueschists yielded metamorphic ages around 82-80 Ma (zircon U-Pb and phengite Ar-Ar data). The Alanya-Bitlis HP belt testifies an additional suture not comparable to the northerly Tavşanlı and Ören-Afyon belts, thus implying an additional oceanic branch of the Neotethys. The most likely eastern lateral continuation of this HP belt is the Bitlis Massif, in SE Turkey. There, eclogites (1.9-2.4 GPa/480-540°C) occur within calc-arenitic meta-sediments and in gneisses of the metamorphic (Barrovian-type) basement. Zircon U-Pb ages revealed 84.4-82.4 Ma for peak metamorphism. Carpholite-bearing HP/LT metasediments representing the stratigraphic cover of the Bitlis Massif underwent 0.8-1.2 GPa/340-400°C at 79-74 Ma (Ar-Ar on white mica). These conditions compares to the Tav

  15. Kuiper Belt Mapping Radar

    NASA Technical Reports Server (NTRS)

    Freeman, A.; Nilsen, E.

    2001-01-01

    Since their initial discovery in 1992, to date only a relatively small number of Kuiper Belt Objects (KBO's) have been discovered. Current detection techniques rely on frame-to-frame comparisons of images collected by optical telescopes such as Hubble, to detect KBO's as they move against the background stellar field. Another technique involving studies of KBO's through occultation of known stars has been proposed. Such techniques are serendipitous, not systematic, and may lead to an inadequate understanding of the size, range, and distribution of KBO's. In this paper, a future Kuiper Belt Mapping Radar is proposed as a solution to the problem of mapping the size distribution, extent, and range of KBO's. This approach can also be used to recover radar albedo and object rotation rates. Additional information is contained in the original extended abstract.

  16. Exploring the Earth's Radiation Belts

    NASA Astrophysics Data System (ADS)

    Daglis, I. A.; Anastasiadis, A.; Chatzichristou, E. T.; Ropokis, G.; Giannakis, O.

    2012-09-01

    We present the outreach efforts of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, intended to provide the general public with simplified information concerning the scientific objectives of the project, its focus and its expected outcomes. MAARBLE involves monitoring of the geospace environment through space and ground-based observations, in order to understand various aspects of the radiation belts (torus-shaped regions encircling the Earth, in which high-energy charged particles are trapped by the geomagnetic field), which have direct impact on human endeavors in space (spacecraft and astronauts exposure). The public outreach website of MAARBLE, besides regular updates with relevant news, also employs a variety of multimedia (image and video galleries) and impressive sounds of space (characteristic sounds such as whistlers or tweeks) related to very low and ultra low frequency (VLF/ULF) electromagnetic waves. It also provides links to some of the most interesting relevant educational activities, including those at partner institutions such as the Institute of Geophysics and Planetary Physics at UCLA, the University of Alberta, the Swedish Institute of Space Physics and the Institute of Atmospheric Physics of the Academy of Sciences of the Czech Republic.

  17. Infrared Kuiper Belt Constraints

    SciTech Connect

    Teplitz, V.L.; Stern, S.A.; Anderson, J.D.; Rosenbaum, D.; Scalise, R.J.; Wentzler, P.

    1999-05-01

    We compute the temperature and IR signal of particles of radius {ital a} and albedo {alpha} at heliocentric distance {ital R}, taking into account the emissivity effect, and give an interpolating formula for the result. We compare with analyses of {ital COBE} DIRBE data by others (including recent detection of the cosmic IR background) for various values of heliocentric distance {ital R}, particle radius {ital a}, and particle albedo {alpha}. We then apply these results to a recently developed picture of the Kuiper belt as a two-sector disk with a nearby, low-density sector (40{lt}R{lt}50{endash}90 AU) and a more distant sector with a higher density. We consider the case in which passage through a molecular cloud essentially cleans the solar system of dust. We apply a simple model of dust production by comet collisions and removal by the Poynting-Robertson effect to find limits on total and dust masses in the near and far sectors as a function of time since such a passage. Finally, we compare Kuiper belt IR spectra for various parameter values. Results of this work include: (1) numerical limits on Kuiper belt dust as a function of ({ital R}, {ital a}, {alpha}) on the basis of four alternative sets of constraints, including those following from recent discovery of the cosmic IR background by Hauser et al.; (2) application to the two-sector Kuiper belt model, finding mass limits and spectrum shape for different values of relevant parameters including dependence on time elapsed since last passage through a molecular cloud cleared the outer solar system of dust; and (3) potential use of spectral information to determine time since last passage of the Sun through a giant molecular cloud. {copyright} {ital {copyright} 1999.} {ital The American Astronomical Society}

  18. The Strongest Mountain

    ERIC Educational Resources Information Center

    Monnes, Colleen

    2004-01-01

    The article describes an activity for the author's fifth-grade students called "build the strongest mountain." To them, it was not a lesson--it was a challenge. To the author, it was an activity that turned a run-of-the-mill Earth science unit into a terrific opportunity for students to demonstrate their knowledge of erosion and develop…

  19. The Beaufort Sea fold-and-thrust belt, northwestern Canada: Implications for thrust-belt evolution

    SciTech Connect

    Root, K.G. )

    1991-06-01

    The northeasternmost segment of the Cordilleran thrust belt of western North American underlies the Beaufort Sea continental margin. Folds and associated northesat-directed thrusts in this region formed synchronously with Tertiary sedimentation. As a result, the times of fold development can be determined from reflection seismic data by analyzing lateral thickness changes in stratigraphic sequences of known ages, and onlap and truncation relationships at unconformities. Thrust faulting occurred throughout the late Paleocene-Pliocene. The abundant temporal data indicate the deformational seuqence was significantly differet from the simple, steplike, foreland-propagating model formulated in other less well-dated thrust belts. Many thrusts were active simultaneously, especially during the late Eocnee, when the region of active thrusting had an across-strike width of greater than 200 km. This observation calls into question the popular concept that only one thrust moves at a time as a thrust belt develops. The thrust belt propagated along, as well as across, strike. During the late Paleocene-middle Eocene, the area of active thrusting was bounded on the southeast by poorly imaged zones of right-lateral strike-slip faults that apparently are the northern offshore continuation of the Rapid fault array. The change in the age of thrusting along strike results in no obvious geometrical anomalies and could not be deduced without timing information. This has an important implication: temporal data cannot necessarily be projected along strike in a thrust belt.

  20. Stone Mountain

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This color image taken by the panoramic camera onboard the Mars Exploration Rover Opportunity shows the part of the rock outcrop dubbed Stone Mountain at Meridiani Planum, Mars. Scientists are examining Stone Mountain with the instruments on the rover's instrument deployment device, or 'arm,' in search of clues about the composition of the rock outcrop. [figure removed for brevity, see original site] A Patch of Stone (Figure credit: NASA/JPL/Cornell/USGS)

    The colorless square in this color image of the martian rock formation called Stone Mountain is one portion of the rock being analyzed with tools on the Mars Exploration Rover Opportunity's instrument deployment device, or 'arm.' The square area is approximately 3 centimeters (1.2 inches) across. Stone Mountain is located within the rock outcrop on Meridiani Planum, Mars. The image was taken by the rover's panoramic camera.

  1. Mountain research

    NASA Astrophysics Data System (ADS)

    The newly incorporated International Mountain Society (IMS) will in May begin publication of an interdisciplinary scientific journal, Mountain Research and Development. The quarterly will be copublished with the United National University; additional support will come from UNESCO.A primary objective of IMS is to ‘help solve mountain land-use problems by developing a foundation of scientific and technical knowledge on which to base management decisions,’ according to Jack D. Ives, president of the Boulder-based organization. ‘The Society is strongly committed to the belief that a rational worldwide approach to mountain problems must involve a wide range of disciplines in the natural and human sciences, medicine, architecture, engineering, and technology.’

  2. Active tectonics of the Devils Mountain Fault and related structures, northern Puget Lowland and eastern Strait of Juan de Fuca region, Pacific Northwest

    USGS Publications Warehouse

    Johnson, Samuel Y.; Dadisman, Shawn V.; Mosher, David C.; Blakely, Richard J.; Childs, Jonathan R.

    2001-01-01

    Information from marine high-resolution and conventional seismic-reflection surveys, aeromagnetic mapping, coastal exposures of Pleistocene strata, and lithologic logs of water wells is used to assess the active tectonics of the northern Puget Lowland and eastern Strait of Juan de Fuca region of the Pacific Northwest. These data indicate that the Devils Mountain Fault and the newly recognized Strawberry Point and Utsalady Point faults are active structures and represent potential earthquake sources.

  3. Airflow-terrain interactions through a mountain gap, with an example of eolian activity beneath an atmospheric hydraulic jump

    SciTech Connect

    Gaylord, D.R.; Dawson, P.J.

    1987-09-01

    The integration of atmospheric soundings from a fully instrumented aircraft with detailed sedimentary and geomorphic analyses of eolian features in the Ferris dune field of south-central Wyoming lends insight into the manner in which topography interacts with airflow to modify eolian activity. Topographically modified airflow results in zones of airflow deceleration, acceleration, and enhanced atmospheric turbulence, all of which influence the surface morphology and sedimentology. Extreme lateral confluence of prevailing airflow produces accelerated, unidirectional winds. These winds correlate with unusually continuous and elongate parabolic dunes that extend into a mountain gap (Windy Gap). Persistently heightened winds produced at the entrance to Windy Gap have resulted in a concentration of active sand dunes that lack slipfaces. Common development of a strongly amplified atmospheric wave analogous to a hydraulic jump in the gap contributes to the formation of a variety of eolian features that mantle the surface of Windy Gap and the Ferris dune field tail. Heightened, unidirectional winds in this zone promote grain-size segregation, the formation of elongated and aligned sand drifts, climbing and falling dunes, elongate scour streaks, and parabolic dunes that have low-angle (< 20/sup 0/) cross-stratification. Deflation of bedrock and loose sediment has been enhanced in the zone of maximum turbulence beneath the hydraulic jump.

  4. SOME NATURAL CONDUIT ANALOGUES FOR POTENTIAL IGNEOUS ACTIVITY AT YUCCA MOUNTAIN

    SciTech Connect

    D.J. Krier; G.N. Keating; G.A. Valentine

    2005-08-26

    Eruptive conduit geometry has direct relation to number of waste packages that would be damaged if a new volcano were to form at the proposed Yucca Mountain radioactive waste repository, and therefore is a key factor in predicting the consequences of such an eruption. Current risk calculations treat conduits as having circular plan view and range from a few meters to 150 m diameter at repository depths ({approx}300 m). We present new observations of shallow basaltic plumbing at analog sites aimed at testing these parameter values. East Grants Ridge. NM, is a remnant of a {approx}2.6 Ma alkali basaltic volcano with a chain of 2-3 vents that fed {approx}10-km long lava flows. The south side of the ridge exposes a plug of vertically jointed, dense basalt that intruded rhyolitic tuffs. The plug is exposed vertically for {approx}125 m, including 40 m beneath the paleosurface, and has a relatively constant width of {approx}135 m with no indication of downward narrowing. The size of the plug in the third dimension is not well known but could extend laterally up to {approx}1.5 km beneath the chain of vents. Paiute Ridge, NV, is an 8.6 Ma alkali basalt intrusion into Paleozoic carbonate and shale and Miocene silicic tuffs and includes extrusive equivalents. Dikes, small sills and lopoliths, scoria, and flows are exposed in a 2 km-wide graben. Depth of intrusion has been estimated at 100-250 m beneath the paleosurface. Dikes range from 3-20 m in width and produced limited contact vitrophyre in the host tuff. At least one sub-volcanic neck is preserved. The top of the plug is {approx}27 m lower than the base of related basalt flows 1 km distant. This neck is irregularly shaped by intersection of feeder dikes and has a sheath of mixed basaltic magma and host tuff (with both breccia and fluidal textures). The basalt interior of the plug is {approx}100 m x 70 m in map view but inclusion of the mixed zone increases this to {approx}220 m x 110 m. Basalt Ridge, NV, contains two

  5. Evolution of Topography in Glaciated Mountain Ranges

    NASA Technical Reports Server (NTRS)

    Brocklehurst, Simon H.

    2002-01-01

    This thesis examines the response of alpine landscapes to the onset of glaciation. The basic approach is to compare fluvial and glacial laudscapes, since it is the change from the former to the latter that accompanies climatic cooling. This allows a detailed evaluation of hypotheses relating climate change to tectonic processes in glaciated mountain belts. Fieldwork was carried out in the eastern Sierra Nevada, California, and the Sangre de Cristo Range, Colorado, alongside digital elevation model analyses in the western US, the Southern Alps of New Zealand, and the Himalaya of northwestern Pakistan. hypothesis is overstated in its appeal to glacial erosion as a major source of relief production and subsequent peak uplift. Glaciers in the eastern Sierra Nevada and the western Sangre de Cristos have redistributed relief, but have produced only modest relief by enlarging drainage basins at the expense of low-relief topography. Glaciers have lowered valley floors and ridgelines by similar amounts, limiting the amount of "missing mass' that can be generated, and causing a decrease in drainage basin relief. The principal response of glaciated landscapes to rapid rock uplift is the development of towering cirque headwalls. This represents considerable relief production, but is not caused by glacial erosion alone. Large valley glaciers can maintain their low gradient regardless of uplift rate, which supports the "glacial buzzsaw" hypothesis. However, the inability of glaciers to erode steep hillslopes as rapidly can cause mean elevations to rise. Cosmogenic isotope dating is used to show that (i) where plucking is active, the last major glaciation removed sufficient material to reset the cosmogenic clock; and (ii) former glacial valley floors now stranded near the crest of the Sierra Nevada are at varying stages of abandonment, suggesting a cycle of drainage reorganiszation and relief inversion due to glacial erosion similar to that observed in river networks. Glaciated

  6. Insights on continental collisional processes from GPS data: Dynamics of the peri-Adriatic belts

    NASA Astrophysics Data System (ADS)

    Métois, M.; D'Agostino, N.; Avallone, A.; Chamot-Rooke, N.; Rabaute, A.; Duni, L.; Kuka, N.; Koci, R.; Georgiev, I.

    2015-12-01

    We present a new GPS velocity field covering the peri-Adriatic tectonically active belts and the entire Balkan Peninsula. From the velocities, we calculate consistent strain rate and interpolated velocity fields. Significant features of the crustal deformation include (1) the eastward motion of the northern part of the Eastern Alps together with part the Alpine foreland and Bohemian Massif toward the Pannonian Basin, (2) shortening across the Dinarides, (3) a clockwise rotation of the Albanides-Hellenides, and (4) a southward motion south of 44°N of the inner Balkan lithosphere between the rigid Apulia and Black Sea, toward the Aegean domain. Using this new velocity field, we derive the strain rate tensor to analyze the regional style of the deformation. Then, we devise a simple test based on the momentum balance equation, to investigate the role of horizontal gradients of gravitational potential energy in driving the deformation in the peri-Adriatic tectonically active mountain belts: the Eastern Alps, the Dinarides, the Albanides, and the Apennines. We show that the strain rate fields observed in the Apennines and Albanides are consistent with a fluid, with viscosity η ˜ 3×1021 Pa s, deforming in response to horizontal gradients of gravitational potential energy. Conversely, both the Dinarides and Eastern Alps are probably deforming in response to the North and North-East oriented motion of the Adria-Apulia indenter, respectively, and as a consequence of horizontal lithospheric heterogeneity.

  7. Yucca Mountain project container fabrication, closure and non-destructive evaluation development activities; Summary and viewgraphs

    SciTech Connect

    Russell, E.W.; Nelson, T.A.

    1989-06-01

    In this presentation, container fabrication, closure, and non-destructive evaluation (NDE) process development activities are described. All of these activities are interrelated, and will contribute to the metal barrier selection activity. The plan is to use a corrosion-resistant material in the form of a cylinder with a wall thickness of {approximately}1cm (2cm for pure copper.) The materials under consideration include the three austenitic alloys: stainless steel-304L, stainless steel-316L and alloy 825, as well as the three copper alloys: CDA 102, CDA 613, and CDA 715. This document reviews the recommended procedures and processes for fabricating, closing and evaluating each of the candidate materials. (KGD)

  8. 30 CFR 77.406 - Drive belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drive belts. 77.406 Section 77.406 Mineral... Mechanical Equipment § 77.406 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing shall not be applied while belts are...

  9. 30 CFR 77.406 - Drive belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drive belts. 77.406 Section 77.406 Mineral... Mechanical Equipment § 77.406 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing shall not be applied while belts are...

  10. 30 CFR 77.406 - Drive belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drive belts. 77.406 Section 77.406 Mineral... Mechanical Equipment § 77.406 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing shall not be applied while belts are...

  11. 30 CFR 77.406 - Drive belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drive belts. 77.406 Section 77.406 Mineral... Mechanical Equipment § 77.406 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing shall not be applied while belts are...

  12. 30 CFR 77.406 - Drive belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drive belts. 77.406 Section 77.406 Mineral... Mechanical Equipment § 77.406 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing shall not be applied while belts are...

  13. Protrusive intrusion, dehydration and polymorphism in minerals as possible reason of seismic activity, relation between ophiolite belts and seismic zonation of the territory of Armenia

    NASA Astrophysics Data System (ADS)

    Harutyunyan, A. V.; Petrosyan, H. M.

    2010-05-01

    In the basis of multiple geological and geophysical data, also on the results of investigations seismic and density properties of rocks at high termobaric conditions, we proposed the petrophisical section and model of evolution of Earth crust of the territory of Armenia. On the proposed model the following interrelated problems are debated: forming of ophiolite belts and volcanic centers, genesis of hydrocarbons by organic and inorganic ways, and also reasons of originating of seismic centers. The reasons of originating of seismic centers in different depths of Earth crust, are miscellaneous. According to the model of Earth crust evolution the ophiolite belts are formed due to permanent protrusive intrusion of serpentinized masses from the foot of the crust (35-50km) into upper horizons. It is natural to assume, that the permanent intrusion of serpentinizd masses through deep faults has drastically occurred accompanying with seismic shakings. This process encourages the development of deep faults. The protrusive intrusion of serpentinized masse accompanied with partial dehydration of serpentinites and serpentinized ultrabasites and new mineral formation. The processes was accompanied also with drastic change of seismic waves and volumes up to 30%. Experiments at high termobaric conditions show, that some minerals undergone polymorphous transformations, accompanied with phase change and drastic change of rocks volume. Particularly plastic calcite, included in the composition of metamorphic rocks to run into the cracks expends and diversifies them. The process described cause some general effects similar to those of the process of dilatancy. Therefore, the protrusive intrusion of serpentinized masses into upper horizons, it dehydrations and polymorphous transformations in different minerals, may be cause of geo-dynamic processes at different depths of Earth crust. It may be assumed, that those processes permanently occur nowadays as well. Comparing the maps of

  14. SLH Timing Belt Powertrain

    SciTech Connect

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  15. Magmatic and metamorphic belts and plutonic-metamorphic complexes of southeastern Alaska

    SciTech Connect

    Brew, D.A.; Himmelberg, G.R.; Ford, A.B.; Loney, R.A. . Branch of Alaskan Geology Univ. of Missouri, Columbia, MO . Dept. of Geology)

    1993-04-01

    The Cordilleran orogen in southeastern Alaska includes 24 distinct magmatic belts, ranging in age from Cambrian to Holocene, that are defined by map relations, lithology, age, and chemical composition. The youngest magmatic features are Quaternary-age pre- and post-glacial volcanic rocks that occur in three major fields in the region, as well as in isolated locations. Cenozoic magmatic features consist of four major and three minor belts. The major Tkope-Portland Peninsula belt of Oligocene age includes both volcanic and plutonic rocks. The major calcalkalic Coast Mountains belt of early and middle Eocene age is the single largest magmatic feature of the region. Early Tertiary and latest Cretaceous magmatism is represented by the major calcalkalic great tonalite sill belt, a remarkable long and narrow feature along the west side of the Coast Mountains. Cretaceous and Jurassic intrusive rocks occur in five major belts and two minor belts in the region and Paleozoic intrusive rocks occur in four major and two minor belts. The three major plutonic-metamorphic complexes (PMC), from east to west, are: the Coast PMC in the Coast Mountains; the Glacier Bay-Chichag of plutonic complex (Chugach MC) in the northern outer islands. The Coast PMC records dynamothermal and regional contact metamorphic events related to regional plutonism within several juxtaposed terranes; its lengthy and complicated history is related to the Late Cretaceous collision of the Alexander and Wrangellia terranes and the Gravina overlap assemblage to the west against the Yukon prong and Stikine terrane to the east. The relatively simple Glacier Bay PC history is recorded as the roots of a Late Jurassic through late Early Cretaceous island arc that probably developed during the early stages of the above tectonic event. The complicated Chugach MC history developed during and after the Late Cretaceous collision of the Chugach terrane with the Wrangellia and Alexander terranes.

  16. A Mountain Child: An Active Learning Pack for 9-13 Year Olds.

    ERIC Educational Resources Information Center

    Lyle, Sue; Jenkins, Alyson

    This resource packet includes a teacher's guide, reproducible student activity sheets, a simulation game: "Life with the Incas", and a poster. The resource presents a cross-curricular thematic approach to the United Kingdom's National Curriculum. The materials look at the Andes and the Andean people, the Quechuan, who live in the Peruvian…

  17. Moving belt metal detector

    NASA Astrophysics Data System (ADS)

    Nelson, Carl V.; Mendat, Deborah P.; Huynh, Toan B.

    2006-05-01

    The Johns Hopkins University Applied Physics Laboratory (APL) has developed a prototype metal detection survey system that will increase the search speed of conventional technology while maintaining high sensitivity. Higher search speeds will reduce the time to clear roads of landmines and improvised explosive devices (IED) and to locate unexploded ordnance (UXO) at Base Realignment and Closure (BRAC) sites, thus reducing remediation costs. The new survey sensor system is called the moving belt metal detector (MBMD) and operates by both increasing sensor speed over the ground while maintaining adequate sensor dwell time over the target for good signal-to-noise ratio (SNR) and reducing motion-induced sensor noise. The MBMD uses an array of metal detection sensors mounted on a flexible belt similar to a tank track. The belt motion is synchronized with the forward survey speed so individual sensor elements remain stationary relative to the ground. A single pulsed transmitter coil is configured to provide a uniform magnetic field along the length of the receivers in ground contact. Individual time-domain electromagnetic induction (EMI) receivers are designed to sense a single time-gate measurement of the total metal content. Each sensor module consists of a receiver coil, amplifier, digitizing electronics and a low power UHF wireless transmitter. This paper presents the survey system design concepts and metal detection data from various targets at several survey speeds. Although the laboratory prototype is designed to demonstrate metal detection survey speeds up to 10 m/s, higher speeds are achievable with a larger sensor array. In addition, the concept can be adapted to work with other sensor technologies not previously considered for moving platforms.

  18. Monitoring and assessment of anthropogenic activities in mountain lakes: a case of the Fifth Triglav Lake in the Julian Alps.

    PubMed

    Ravnikar, Tina; Bohanec, Marko; Muri, Gregor

    2016-04-01

    The Fifth Triglav Lake is a remote mountain lake in the Julian Alps. The area of the Julian Alps where the lake is situated is protected by law and lies within the Triglav National Park. Mountain lakes in Slovenia were considered for a long time as pristine, unpolluted lakes, but analyses in the last decade revealed considerable human impact even in such remote places. Eutrophication or excessive accumulation of nutrients is the main problem of most lakes in the temperate climatic zone, also in Slovenia. Since the introduction of fish in 1991, the lake is going through a series of changes for which we do not know exactly where they lead, so the monitoring and assessment of anthropogenic activities are of great importance. For this purpose, a qualitative multiattribute decision model was developed with DEX method to assess ecological effects on the lake. The extent of the ecological effects on the lake is assessed using four main parameters: the trophic state, lake characteristics, environmental parameters, and anthropogenic stressors. Dependence of environmental impact on various external factors beyond human control, such as temperature, precipitation, retention time, and factors on which we have influence, such as the amount of wastewater and the presence of fish in the lake, were also evaluated. The following data were measured: chlorophyll a, nutrients, TP, oxygen, C/N ratio, nutrients in sediment, temperature, precipitation, retention time, and volume. We made assumptions about fish and wastewater, which we could not measure. The main contributions of this work are the designed model and the obtained findings for the Fifth Triglav Lake that can help not only scientists in understanding the complexity of lake-watershed systems and interactions among system components but also local authorities to manage and monitor the lake aquatic environment in an effective and efficient way. The model is flexible and can be also used for other lakes, assuming that the used

  19. Monitoring and assessment of anthropogenic activities in mountain lakes: a case of the Fifth Triglav Lake in the Julian Alps.

    PubMed

    Ravnikar, Tina; Bohanec, Marko; Muri, Gregor

    2016-03-01

    The Fifth Triglav Lake is a remote mountain lake in the Julian Alps. The area of the Julian Alps where the lake is situated is protected by law and lies within the Triglav National Park. Mountain lakes in Slovenia were considered for a long time as pristine, unpolluted lakes, but analyses in the last decade revealed considerable human impact even in such remote places. Eutrophication or excessive accumulation of nutrients is the main problem of most lakes in the temperate climatic zone, also in Slovenia. Since the introduction of fish in 1991, the lake is going through a series of changes for which we do not know exactly where they lead, so the monitoring and assessment of anthropogenic activities are of great importance. For this purpose, a qualitative multiattribute decision model was developed with DEX method to assess ecological effects on the lake. The extent of the ecological effects on the lake is assessed using four main parameters: the trophic state, lake characteristics, environmental parameters, and anthropogenic stressors. Dependence of environmental impact on various external factors beyond human control, such as temperature, precipitation, retention time, and factors on which we have influence, such as the amount of wastewater and the presence of fish in the lake, were also evaluated. The following data were measured: chlorophyll a, nutrients, TP, oxygen, C/N ratio, nutrients in sediment, temperature, precipitation, retention time, and volume. We made assumptions about fish and wastewater, which we could not measure. The main contributions of this work are the designed model and the obtained findings for the Fifth Triglav Lake that can help not only scientists in understanding the complexity of lake-watershed systems and interactions among system components but also local authorities to manage and monitor the lake aquatic environment in an effective and efficient way. The model is flexible and can be also used for other lakes, assuming that the used

  20. Human impacts to mountain streams

    NASA Astrophysics Data System (ADS)

    Wohl, Ellen

    2006-09-01

    Mountain streams are here defined as channel networks within mountainous regions of the world. This definition encompasses tremendous diversity of physical and biological conditions, as well as history of land use. Human effects on mountain streams may result from activities undertaken within the stream channel that directly alter channel geometry, the dynamics of water and sediment movement, contaminants in the stream, or aquatic and riparian communities. Examples include channelization, construction of grade-control structures or check dams, removal of beavers, and placer mining. Human effects can also result from activities within the watershed that indirectly affect streams by altering the movement of water, sediment, and contaminants into the channel. Deforestation, cropping, grazing, land drainage, and urbanization are among the land uses that indirectly alter stream processes. An overview of the relative intensity of human impacts to mountain streams is provided by a table summarizing human effects on each of the major mountainous regions with respect to five categories: flow regulation, biotic integrity, water pollution, channel alteration, and land use. This table indicates that very few mountains have streams not at least moderately affected by land use. The least affected mountainous regions are those at very high or very low latitudes, although our scientific ignorance of conditions in low-latitude mountains in particular means that streams in these mountains might be more altered than is widely recognized. Four case studies from northern Sweden (arctic region), Colorado Front Range (semiarid temperate region), Swiss Alps (humid temperate region), and Papua New Guinea (humid tropics) are also used to explore in detail the history and effects on rivers of human activities in mountainous regions. The overview and case studies indicate that mountain streams must be managed with particular attention to upstream/downstream connections, hillslope

  1. Soil Microbial Biomass, Basal Respiration and Enzyme Activity of Main Forest Types in the Qinling Mountains

    PubMed Central

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  2. Soil microbial biomass, basal respiration and enzyme activity of main forest types in the Qinling Mountains.

    PubMed

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  3. The Overthrust Belt of Western North America

    SciTech Connect

    Verrall, P.

    1993-02-01

    The Overthrust Belt extends for 5000 mi (8000 km) from the Brooks Range in Alaska to the Sierra Madre Oriental in Mexico. It consists of northeastward vergent thrust and fold structures involving late Precambrian to early Tertiary sedimentary section. These sediments represent deposition off the western rift margin, formed in late Precambrian time, of the North American Precambrian craton. The northeastward thrusting continued throughout the Mesozoic as a response to the convergence of the East Pacific Plate with the North American Plate. This convergence resulted in subduction beneath the North American Plate except at the northwest end (the Brooks Range) where the result was obduction. Convergence ceased when the west edge of the East Pacific Plate reached the subduction zone. The sedimentary section involved in the Thrust Belt contains good Devonian to Cretaceous hydrocarbon source rocks, and Ordovician to traps related to the thrusting (simple thrust sheets, imbricate thrust sheets, folded thrust sheets, step anticlines, footwall cutoffs, footwall anticlines, etc.). Field methods involved in exploration for hydrocarbons include field geological mapping, remote sensing (aerial photography and Landsat imagery), various seismic refraction and seismic reflection techniques (including modern detailed three dimension surveys) and potential field methods such as gravity and magnetic surveying. Studies of the field data include paleontology, source rock and hydrocarbon migration studies, structural and stratigraphic analyses, and the processing of geophysical data. This work has succeeded in two major areas: the Western Canadian Rocky Mountain Foothills, a major gas province producing mainly from Paleozoic reservoirs; and the Wyoming-Idaho-Utah portion of the thrust belt, also a major gas producer from Paleozoic reservoirs and, in addition, a major oil producer from the Jurassic Nugget Sandstone.

  4. Flexural bending-induced plumelets and their seamounts in accretionary (Japanese-style) and collisional (Tethyan-style) orogenic belts

    NASA Astrophysics Data System (ADS)

    Hirano, N.; Dilek, Y.

    2015-12-01

    Seamounts and seamount chains are common in both the upper and lower plates of active subduction zones. Their OIB-type volcanic products are distinctly different from suprasubduction zone (arc, forearc and backarc) generated volcanic rocks in terms of their compositions and mantle sources. Tectonic accretion of such seamounts into the Japanese archipelago in the NW Pacific and into subduction-accretion complexes and active margins of continents/microcontinents within the Tethyan realm during the Cretaceous played a significant role in continental growth. Seamount assemblages comprise alkaline volcanic rocks intercalated with radiolarian and hemipelagic chert, and limestone, and may also include hypabyssal dolerite and gabbro intrusions. In the Tethyan orogenic belts these seamount rocks commonly occur as km-scale blocks in mélange units beneath the late Jurassic - Cretaceous ophiolites nappes, whereas on the Japanese islands they form discrete, narrow tectonic belts within the late Jurassic - Cretaceous accretionary prism complexes. We interpret some of these OIB occurrences in the Japanese and Tethyan mountain belts as asperities in downgoing oceanic plates that formed in <10 million years before their accretion. Their magmas were generated by decompressional melting of upwelling asthenosphere, without any significant mantle plume component, and were brought to the seafloor along deep-seated brittle fractures that developed in the flexed, downgoing lithosphere as it started bending near a trench. The modern occurrences of these "petit-spot volcanoes" are well established in the northwestern Pacific plate, off the coast of Japan. The proposed mechanism of the formation of these small seamounts better explains the lack of hotspot trails associated with their occurrence in the geological record. Magmatic outputs of such flexural bending-induced plumelets should be ubiquitious in the accretionary (Japanese-style) and collisional (Tethyan-style) orogenic belts.

  5. Response of soil microbial activity and community structure to land use changes in a mountain rainforest region of Southern Ecuador

    NASA Astrophysics Data System (ADS)

    Potthast, Karin; Hamer, Ute; Makeschin, Franz

    2010-05-01

    Over the past several decades the mountain rainforest region of Southern Ecuador, a hotspot of biodiversity, is undergoing a rapid conversion to pastureland through slash and burn practice. Frequently this pastureland is invaded by the tropical bracken fern. When the bracken becomes dominant on the pasture sites the productivity decreases and the sites are abandoned. To assess the effect of these land use changes on nutrient turnover and on ecosystem functioning, a study was conducted in the area of the German research station Estación Científica San Francisco (ECSF) in Southern Ecuador. At 2000 m above sea level three adjacent sites were selected: a mountain rainforest site, an active pasture site dominated by the grass species Setaria sphacelata and an abandoned pasture site overgrown by bracken. Mineral soil samples of all three sites (0-5, 5-10 and 10-20 cm) as well as samples from the organic layer (Oi and Oa) of the natural forest site were taken to analyze biogeochemical properties. Besides pH-value, total organic C and N contents, the amounts of microbial biomass (CFE-method), microbial activity (basal respiration, net N mineralization (KCl-extraction); gross N mineralization (15N dilution technique) rates) and microbial community structure (PLFA-analysis) were determined. 17 years after pasture establishment, twofold higher stocks of soil microbial biomass carbon (Cmic) and nitrogen (Nmic) as well as significant lower C:N ratios were determined compared to the natural forest including the 11 cm thick organic layer. 10 years after bracken invasion and pasture abandonment the microbial biomass (Cmic) decreased and the C:N ratio increased again to forest levels. Generally, land use change from forest to pasture and from pasture to abandoned pasture induced shifts in the soil microbial community structure. The relative abundance of the fast growing copiotrophic Gram(-) bacteria was positively correlated with the amounts of readily available organic carbon

  6. Human and climate impacts on Holocene fire activity recorded in polar and mountain ice cores

    NASA Astrophysics Data System (ADS)

    Kehrwald, Natalie; Zennaro, Piero; Kirchgeorg, Torben; Li, Quanlian; Wang, Ninglian; Power, Mitchell; Zangrando, Roberta; Gabrielli, Paolo; Thompson, Lonnie; Gambaro, Andrea; Barbante, Carlo

    2014-05-01

    Fire is one of the major influences of biogeochemical change on local to hemispheric scales through emitting greenhouse gases, altering atmospheric chemistry, and changing primary productivity. Levoglucosan (1,6-anhydro-β-D-glucopyranose) is a specific molecular that can only be produced by cellulose burning at temperatures > 300°C, comprises a major component of smoke plumes, and can be transported across > 1000 km distances. Levoglucosan is deposited on and archived in glaciers over glacial interglacial cycles resulting in pyrochemical evidence for exploring interactions between fire, climate and human activity. Ice core records provide records of past biomass burning from regions of the world with limited paleofire data including polar and low-latitude, high-altitude regions. Here, we present Holocene fire activity records from the NEEM, Greenland (77° 27'N; 51° 3'W; 2454 masl), EPICA Dome C, Antarctica (75° 06'S; 123° 21'E; 3233 masl), Kilimanjaro, Tanzania (3° 05'S, 21.2° E, 5893 masl) and the Muztagh, China (87.17° E; 36.35° N; 5780 masl ice cores. The NEEM ice core reflects boreal fire activity from both North American and Eurasian sources. Temperature is the dominant control of NEEM levoglucosan flux over decadal to millennial time scales, while droughts influence fire activity over sub-decadal timescales. Our results demonstrate the prominence of Siberian fire sources during intense multiannual droughts. Unlike the NEEM core, which incorporates the largest land masses in the world as potential fire sources, EPICA Dome C is located far from any possible fire source. However, EPICA Dome C levoglucosan concentrations are consistently above detection limits and demonstrate a substantial 1000-fold increase in fire activity beginning approximately 800 years ago. This significant and sustained increase coincides with Maori arrival and dispersal in New Zealand augmented by later European arrival in Australia. The EPICA Dome C levoglucosan profile is

  7. Radioprotective effects of active compounds from Acanthopanax senticosus of Lesser Khingan Mountain in China

    NASA Astrophysics Data System (ADS)

    Lu, Weihong; Sun, Yeqing; Shi, Jinming

    Bioactive compounds including polysaccharides, flavones, syringin and eleutheroside E were extracted from wild Acanthopanax senticosus and purified by chromatography. In vitro and in vivo anti-radiation activities of the compounds were compared. In vitro radical scavenging results showed that polysaccharides and flavones were more effective than syringin and eleutheroside E in In vivo study proved that polysaccharides and flavones were effective in protecting mice from heavy ion radiation induced oxidative damages. Also, the activity of polysaccharides and flavones in repressing expression changes of radiation response proteins including heat shock protein, disulfide-isomerase and glutathione S-transferase were also found by our results. Moreover, the radioprotective effects were more significant when polysaccharides and flavones were used together.

  8. Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel

    PubMed Central

    Yuan, Liming; Smith, Alex C.

    2015-01-01

    Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect. PMID:26190905

  9. Recent rock fall activity in the Wetterstein Mountains revealed by a time series of terrestrial laser scans

    NASA Astrophysics Data System (ADS)

    Schöpa, Anne; Baewert, Henning; Cook, Kristen; Morche, David

    2015-04-01

    The north face of the Hochwanner in the Reintal valley, Wetterstein Mountains, southern Germany, has been a site of frequent rock fall activity for the past several hundred years. The so-called 'Steingerümpel' rock fall included an estimated volume of 2.3-2.7 x 106 m3 and led to damming of the Partnach river. This event was dated to 1400-1600 AD. The rock fall left a prominent scar in the rock face where subsequent rock fall activity was concentrated, postulated to be a 'delayed consequence' of the Steingerümpel event. Previous workers used airborne and terrestrial laser scan data to evaluate the volume of the detached material and the deposits on the talus cone at the foot of the slope from the 'delayed consequence' activity between 2006 and 2008 (Heckmann et al., 2012). The largest event during this period was a 5 x 104 m3 rock fall in August 2007. We compared the data of six terrestrial laser scans, which were acquired in June and September 2008, September 2010, June 2011, August 2013, October and November 2014, in order to assess the volumes of detached material after the large rock fall event of 2007. The aim is to investigate the post-event activity at a site of a large rock fall in order to give estimates about the timing when the activity is back to normal conditions in relation to the magnitude of the large event. Although no large rock fall occurred in the observation period, the comparison of the laser scan data indicate that the average rock wall retreat at this site is still higher compared to the mean annual rock wall retreat rate of 0.54 mm/yr for the last millennium in the Reintal valley (Krautblatter et al., 2012). This shows that sites of large rock falls remain active even years after the event. Heckmann, T.; Bimböse, M.; Krautblatter, M.; Haas, F.; Becht, M.; Morche, D. (2012): From geotechnical analysis to quantification and modelling using LiDAR data: a study on rockfall in the Reintal catchment, Bavarian Alps, Germany; Earth Surface

  10. Highly Active Microbial Communities in the Ice and Snow Cover of High Mountain Lakes

    PubMed Central

    Felip, M.; Sattler, B.; Psenner, R.; Catalan, J.

    1995-01-01

    An exploratory study carried out in Pyrenean and Alpine lakes shows that a rich, active microbial community lives in the slush layers of the winter cover of such lakes in spite of the low temperature and the seasonal occurrence of the habitat. Bacteria were very diverse in morphology, with filaments reaching up to 100 (mu)m long; flagellates, both autotrophic (chrysophytes, cryptophytes, dinoflagellates, and volvocales) and heterotrophic, and ciliates were abundant, reaching biovolume values up to 2.7 x 10(sup6) (mu)m(sup3) ml(sup-1). Species composition was very variable, with dominance depending on date and depth. Although many species were typical of lake plankton communities, some were restricted to the slush, for instance the predatory ciliates Dileptus sp. and Lacrymaria sp., and others were restricted to the surface pools, such as the snow algae Chlamydomonas nivalis. Microbial biomasses and usually bacterial and algal activities were greater in the slush layers than in the lake water. Photosynthesis rate in the upper cover layers reached values up to 0.5 (mu)g of C liter(sup-1) h(sup-1), and high bacterial activities up to 226 pmol of leucine incorporated liter(sup-1) h(sup-1) and 25 pmol of thymidine incorporated liter(sup-1) h(sup-1) were measured. For most species, lake water flooding the ice and snow cover could provide an inoculum. Differential growth depending on the environmental conditions (nutrients, organic matter, light) of a particular slush layer could provide dominance of different groups or species. However, there was no obvious colonizing mechanism for those species not appearing either in plankton or in communities on top of the snowpack. PMID:16535056

  11. Highly active microbial communities in the ice and snow cover of high mountain lakes.

    PubMed

    Felip, M; Sattler, B; Psenner, R; Catalan, J

    1995-06-01

    An exploratory study carried out in Pyrenean and Alpine lakes shows that a rich, active microbial community lives in the slush layers of the winter cover of such lakes in spite of the low temperature and the seasonal occurrence of the habitat. Bacteria were very diverse in morphology, with filaments reaching up to 100 (mu)m long; flagellates, both autotrophic (chrysophytes, cryptophytes, dinoflagellates, and volvocales) and heterotrophic, and ciliates were abundant, reaching biovolume values up to 2.7 x 10(sup6) (mu)m(sup3) ml(sup-1). Species composition was very variable, with dominance depending on date and depth. Although many species were typical of lake plankton communities, some were restricted to the slush, for instance the predatory ciliates Dileptus sp. and Lacrymaria sp., and others were restricted to the surface pools, such as the snow algae Chlamydomonas nivalis. Microbial biomasses and usually bacterial and algal activities were greater in the slush layers than in the lake water. Photosynthesis rate in the upper cover layers reached values up to 0.5 (mu)g of C liter(sup-1) h(sup-1), and high bacterial activities up to 226 pmol of leucine incorporated liter(sup-1) h(sup-1) and 25 pmol of thymidine incorporated liter(sup-1) h(sup-1) were measured. For most species, lake water flooding the ice and snow cover could provide an inoculum. Differential growth depending on the environmental conditions (nutrients, organic matter, light) of a particular slush layer could provide dominance of different groups or species. However, there was no obvious colonizing mechanism for those species not appearing either in plankton or in communities on top of the snowpack. PMID:16535056

  12. Growth of the Zagros Fold-Thrust Belt and Foreland Basin, Northern Iraq, Kurdistan

    NASA Astrophysics Data System (ADS)

    Koshnaw, Renas; Horton, Brian; Stockli, Daniel; Barber, Douglas; Ghalib, Hafidh; Dara, Rebwar

    2016-04-01

    The Zagros orogenic belt in the Middle Eastern segment of the Alpine-Himalayan system is among the youngest seismically active continental collision zones on Earth. However, due to diachronous and incremental collision, the precise ages and kinematics of shortening and deposition remain poorly understood. The Kurdistan region of the Zagros fold-thrust belt and foreland basin contains well-preserved Neogene wedge-top and foredeep deposits that include clastic nonmarine fill of the Upper Fars, Lower Bakhtiari, and Upper Bakhtiari Formations. These deposits record significant information about orogenic growth, fold-thrust dynamics, and advance of the deformation front. Thermochronologic and geochronologic data from thrust sheets and stratigraphic archives combined with local earthquake data provide a unique opportunity to address the linkages between surface and subsurface geologic relationships. This research seeks to constrain the timing and geometry of exhumation and deformation by addressing two key questions: (1) Did the northwestern Zagros fold-thrust belt evolve from initial thin-skinned shortening to later thick-skinned deformation or vice-versa? (2) Did the fold-thrust belt advance steadily under critical/supercritical wedge conditions involving in-sequence thrusting or propagate intermittently under subcritical conditions with out-of-sequence deformation? From north to south, apatite (U-Th)/He ages from the Main Zagros Thrust, the Mountain Front Flexure (MFF), and additional frontal thrusts suggest rapid exhumation by ~10 Ma, ~5 Ma, and ~8 Ma respectively. Field observations and seismic sections indicate progressive tilting and development of growth strata within the Lower Bakhtiari Formation adjacent to the frontal thrusts and within the Upper Bakhtiari Formation near the MFF. In the Kurdistan region of Iraq, a regional balanced cross section constrained by new thermochronometric results, proprietary seismic reflection profiles, and earthquake hypocenters

  13. Gould Belt Origin

    NASA Astrophysics Data System (ADS)

    Rivera, Leticia; Loinard, Laurent; Dzib, Sergio

    2013-07-01

    Using archive VLA data and recent observations on the Karl G. Jansky Very Large Array it is worked on a semi-automatic python/CASA code to select, reduce and plot several young stars belonging to the Ophiuchus core. This code mean to help to select observations made along the 30 years of the VLA done in the selected area with the wide configurations A and B, and in the X and C band, to determine their position and compare it with the most recent ones. In this way it is possible to determinate their proper motion with very high precision. It is presented the phases of the process and our first results worked on three well know stars: S1, DoAr 21 and VLA1623. This is the tip of a bigger work that includes Taurus molecular cloud and other important recent star formation regions belonging to the Gould Belt. Our goal is to support the most suitable among several theories about Gould Belt origin or provide a new one taking in count the dynamics of those regions.

  14. Impacts of direct human activity and climate change on north Ethiopian mountain landscapes over 140 Years

    NASA Astrophysics Data System (ADS)

    Nyssen, Jan; Frankl, Amaury; Haile, Mitiku; Hurni, Hans; Descheemaeker, Katrien; Ritler, Alfons; Crummey, Donald; Nievergelt, Bernhard; Moeyersons, Jan; Munro, Neil

    2010-05-01

    Studies on recent environmental change in tropical areas are generally conducted over limited time scales. This study makes a multi-scale assessment over a time span of 140 years, in one of the world's most degraded areas: the highlands of Northern Ethiopia. 300 landscapes, pictured on historical photographs, starting 1868, were re-photographed and environmental changes apparent on the paired photographs were analysed through expert rating. General tendencies appearing include an improved vegetation cover nowadays as compared to any period of the last 140 years, with a second optimum in the early 20th century. In the uppermost areas (above 3500 m a.s.l.) an upward shift of the upper tree line (Erica arborea) is observed, demonstrating that global warming takes also place in this region. At lower elevations, increased vegetation cover is the result of 25 years of intense rehabilitation activities. Physical soil and water conservation follows the same trend. Regional variations occurring in these trends are observed and discussed. The findings are substantiated by field investigations. The positive changes that result from these conservation activities in the north Ethiopian highlands are an issue of global concern as they show that (1) in our study area direct human impact on the environment is overriding and (2) severe land degradation should not always be irreversible.

  15. Active tectonics of the Binalud Mountains, a key puzzle segment to describe Quaternary deformations at the northeastern boundary of the Arabia-Eurasia collision

    NASA Astrophysics Data System (ADS)

    Shabanian, Esmaeil; Bellier, Olivier; Siame, Lionel L.; Abbassi, Mohammad R.; Leanni, Laetitia; Braucher, Régis; Farbod, Yassaman; Bourlès, Didier L.

    2010-05-01

    In northeast Iran, the Binalud Mountains accommodate part of active convergence between the Arabian and Eurasian plates. This fault-bounded mountain range has been considered a key region to describe Quaternary deformations at the northeastern boundary of the Arabia-Eurasia collision. But, the lack of knowledge on active faulting hampered evaluating the geological reliability of tectonic models describing the kinematics of deformation in northeast Iran. Morphotectonic investigations along both sides of the Binalud Mountains allowed us to characterize the structural and active faulting patterns along the Neyshabur and Mashhad fault systems on the southwest and northeast sides of the mountain range, respectively. We applied combined approaches of morphotectonic analyses based on satellite imageries (SPOT5 and Landsat ETM+), STRM and site-scale digital topographic data, and field surveys complemented with in situ-produced 10Be exposure dating to determine the kinematics and rate of active faulting. Three regional episodes of alluvial surface abandonments were dated at 5.3±1.1 kyr (Q1), 94±5 kyr (Q3), and 200±14 kyr (S3). The geomorphic reconstruction of both vertical and right-lateral fault offsets postdating these surface abandonment episodes yielded Quaternary fault slip rates on both sides of the Binalud Mountains. On the Neyshabur Fault System, thanks to geomorphic reconstructions of cumulative offsets recorded by Q3 fan surfaces, slip rates of 2.7±0.8 mm/yr and 2.4±0.2 mm/yr are estimated for right-lateral and reverse components of active faulting, respectively. Those indicate a total slip rate of 3.6±1.2 mm/yr for the late Quaternary deformation on the southwest flank of the Binalud Mountains. Reconstructing the cumulative right-lateral offset recorded by S3 surfaces, a middle-late Quaternary slip rate of 1.6±0.1 mm/yr is determined for the Mashhad Fault System. Altogether, our geomorphic observations reveal that, on both sides of the Binalud Mountains

  16. Caucasus Mountains

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Often regarded as the southeastern border of Europe, the Caucasus Mountains can be seen here stretching from the Black Sea (left) to the Caspian Sea (right). The mountain range spans 700 miles (1125 km), crossing the countries of Russian Federation, Georgia, and Azerbaijan from left to right respectively. With a snowline of approximately 11,000 feet and peaks such as Mt. Elbrus, that reach 15,000 feet, much of the snow visible in this image is present year round. Also visible in this image are apparent phytoplankton blooms in the Caspian Sea, marked by blue-green swirls.

  17. Of mermaids and mountains. Three decades of prompt activation in vivo.

    PubMed

    Morgan, W D

    2000-05-01

    During 1966 to 1972, several laboratories demonstrated the feasibility of measuring the major body elements H, N, Ca, and Cl by prompt gamma in vivo neutron activation analysis (PGIVNA). The MERMAID facility in Birmingham, England used a cyclotron-produced pulsed neutron beam, but other groups in the United Kingdom, United States, Canada, and New Zealand subsequently developed systems based on radioisotope neutron sources that could measure body nitrogen with a precision of a margin of error of a few percentage points. The accuracy of N measurement was greatly enhanced by Vartsky's internal standardization, using prompt-gamma H as the marker and total body hydrogen (based on total body water and skinfolds) as the reference. Chlorine and extracellular water volume were used in a similar way by the Swansea group to calibrate the prompt-gamma analysis of total body calcium. The PGIVNA technique is most valuable in assessing nutritional status, particularly in relation to body protein. PMID:10865724

  18. Geography of the asteroid belt

    NASA Technical Reports Server (NTRS)

    Zellner, B. H.

    1978-01-01

    The CSM classification serves as the starting point on the geography of the asteroid belt. Raw data on asteroid types are corrected for observational biases (against dark objects, for instance) to derive the distribution of types throughout the belt. Recent work on family members indicates that dynamical families have a true physical relationship, presumably indicating common origin in the breakup of a parent asteroid.

  19. The deep structure of retrowedge thrust belts: New insight from Taiwan and the role of secondary subduction

    NASA Astrophysics Data System (ADS)

    Hsieh, Yu-Huan; Suppe, John; Liu, Char-Shine; Carena, Sara

    2016-04-01

    Retrowedge thrust belts commonly develop on the backsides of collisional mountain belts, displaying a vergence opposite to the overall foreland vergence and to the presumed deep-seated subduction polarity. For example, the Southern Alps are a well-known retrowedge whose structures verge southward over the Adria plate, in contrast with the general north vergence of alpine structure over the European foreland. Numerous models have been constructed to explain the deep structure of such bivergent collisional mountain belts in relation to subduction polarity. However, the details of how these upper crustal thrust belts root into the lower crust and link to the subducting mantle lithosphere, defining the fundamental collisional kinematics, remains relatively unconstrained from a direct observational point of view. Here we present a synthesis of new observational constraints on the deep crustal and lithospheric structure of the currently active (~25-30mm/y) retrowedge thrust belt within the larger (90mm/y) Taiwan arc-continent collision between the Philippine Sea plate and the Eurasian stable continental margin. We make use of high-resolution local and global tomography and abundant well-located seismicity to define the deep structure and we use geodesy, surface geology, high-resolution bathymetry and new pre-stack depth migration of reflection profiles in the retrowedge thrust belt to define upper crustal structure and kinematics. The western Taiwan prowedge thrust belt has been converging with Eurasia at ~30mm/y based on geodesy, neotectonic observations (30Ka), and forland basin migration rate (~3-3.5Ma). This equals the long-term subduction rate of Eurasia based on ~450km of subducted slab since the onset of Eurasian subduction at ~15Ma. The remaining ~60mm/y of current plate convergence is taken up by deformation of the edge of the Philippine Sea plate since ~2Ma. Within the upper crust, approximately 60% of this convergence (30-35mm/y) is taken up by west

  20. Folding kinematics expressed in fracture patterns: An example from the Anti-Atlas fold belt, Morocco

    NASA Astrophysics Data System (ADS)

    Ismat, Zeshan

    2008-11-01

    The Anti-Atlas fold belt, Morocco, formed during the same Variscan collisional event that produced the Valley-and-Ridge fold-thrust belt of the Appalachian mountains. Both are external belts of the Appalachian-Ouachita-Mauritanides chain and at the map scale have very similar topographic expressions. The Anti-Atlas, however, consists of map-scale folds that are buckle-related, detachment folds, whereas the Valley-and-Ridge folds developed in response to imbricate thrusting. For this reason, the Anti-Atlas is referred to as a fold belt rather than a fold-thrust belt. This paper examines Variscan folding processes in the Anti-Atlas Mountains. Folding in some layers occurred by sliding along a penetrative network of mesoscale fractures, i.e. cataclastic flow, during buckling. Layer-parallel shortening fractures were reactivated in the later stages of folding to accommodate limb rotation. Although 'boutonnieres', i.e. basement uplifts, punctuate the fold belt, the fracture patterns indicate that the uplifts failed to provide any 'bending' component. Folding is also interpreted to occur under low to moderate confining pressures because the fracture network includes conjugate shear fractures with very small (˜20°) dihedral angles.

  1. Magnificent Mountains

    ERIC Educational Resources Information Center

    Anderson, Heather

    2004-01-01

    One way to increase awareness of endangered national heritage is to teach youth the importance of the land through the study of selected works of art. This article describes a lesson, in which students will study the work of Thomas Moran and create a mountain range collage. A short biography of Thomas Moran is included.

  2. Post-seismic erosional characteristics of the Chiufenershan landslide : Implications for erosion process of tectonically active mountains

    NASA Astrophysics Data System (ADS)

    Chan, Yu-Chang; Lu, Chiao-Yin; Chang, Kou-Jen; Chen, Rou-Fei

    2010-05-01

    The island of Taiwan is resulted from the collision between the Philippine sea plate and the Eurasian plate. The subtropical climate and averaging four typhoons annually, combined with frequent earthquakes, influence much of the Taiwan region. Due to the factors above, not only the active orogeny of Taiwan causes the high uplift rate at about 4 mm/yr, but also drive amazing erosion rate of about 3~6 mm/yr. Previous study indicated approximately 1.9% of global suspended sediment is derived from the small island of Taiwan, which is only about 0.024% of Earth's subaerial surface. Furthermore, modern erosion rates are strongly influenced by large earthquakes and typhoons, and the sediment fluxes after the Mw 7.6 Chi-Chi earthquake of Taiwan are much higher than those before the earthquake. Here we study the Chiufenerhshan landslide, which is one of the large landslides triggered by the Chi-Chi earthquake in the central Taiwan. The avalanche transported a mass of sedimentary rock about 60 m thick and 1.5 km long. Based on the high-resolution topographic data sets from LiDAR or photogrammetry at various years and rain fall data, we have reached the following conclusions: In the period of 8.5 years after the Chi-Chi earthquake, almost 4.2% of the landslide deposits were transported out of the landslide system. Comparing with the mean annual erosion rate of 3~6 mm/yr in Taiwan, the sediment brought out of Chiufenerhshan landslide area is 89.4 mm/yr, a significant amount contributed by the landslide. The mean sediment discharge from this small system is as large as 0.064% of the sediment discharge from the whole Taiwan annually; while the area is only about 0.005% of Taiwan's subaerial surface. Thus, the landslide process has contributed much more to the surface erosion of the Taiwan mountain than other erosion processes.

  3. Prediction of landslide activation at locations in Beskidy Mountains using standard and real-time monitoring methods

    NASA Astrophysics Data System (ADS)

    Bednarczyk, Z.

    2012-04-01

    The paper presents landslide monitoring methods used for prediction of landslide activity at locations in the Carpathian Mountains (SE Poland). Different types of monitoring methods included standard and real-time early warning measurement with use of hourly data transfer to the Internet were used. Project financed from the EU funds was carried out for the purpose of public road reconstruction. Landslides with low displacement rates (varying from few mm to over 5cm/year) had size of 0.4-2.2mln m3. Flysch layers involved in mass movements represented mixture of clayey soils and sandstones of high moisture content and plasticity. Core sampling and GPR scanning were used for recognition of landslide size and depths. Laboratory research included index, IL oedometer, triaxial and direct shear laboratory tests. GPS-RTK mapping was employed for actualization of landslide morphology. Instrumentation consisted of standard inclinometers, piezometers and pore pressure transducers. Measurements were carried 2006-2011, every month. In May 2010 the first in Poland real-time monitoring system was installed at landslide complex over the Szymark-Bystra public road. It included in-place uniaxial sensors and 3D continuous inclinometers installed to the depths of 12-16m with tilt sensors every 0.5m. Vibrating wire pore pressure and groundwater level transducers together with automatic meteorological station analyzed groundwater and weather conditions. Obtained monitoring and field investigations data provided parameters for LEM and FEM slope stability analysis. They enabled prediction and control of landslide behaviour before, during and after stabilization or partly stabilization works. In May 2010 after the maximum precipitation (100mm/3hours) the rates of observed displacements accelerated to over 11cm in a few days and damaged few standard inclinometer installations. However permanent control of the road area was possible by continuous inclinometer installations. Comprehensive

  4. The 1989 earthquake swarm beneath Mammoth Mountain, California: an initial look at the 4 May through 30 September activity

    USGS Publications Warehouse

    Hill, D.P.

    1990-01-01

    Mammoth Mountain is a 50 000- to 200 000-yr-old cumulovolcano standing on the southwestern rim of Long Valley in eastern California. On 4 May 1989, two M=1 earthquakes beneath the south flank of the mountain marked the onset of a swarm that has continued for more than 6 months. In addition to its longevity, noteworthy aspects of this persistent swarm are described. These aspects of the swarm, together with its location along the southern extension of the youthful Mono-Inyo volcanic chain, which last erupted 500 to 600 yr ago, point to a magmatic source for the modest but persistent influx of strain energy into the crust beneath Mammoth Mountain. -from Authors

  5. Geomorphological approach in karstic domain: importance of underground water in the Jura mountains.

    NASA Astrophysics Data System (ADS)

    Rabin, Mickael; Sue, Christian; Champagnac, Jean Daniel; Bichet, Vincent; Carry, Nicolas; Eichenberger, Urs; Mudry, Jacques; Valla, Pierre

    2014-05-01

    The Jura mountain belt is the north-westernmost and one of the most recent expressions of the Alpine orogeny (i.e. Mio-Pliocene times). The Jura has been well studied from a structural framework, but still remains the source of scientific debates, especially regarding its current and recent tectonic activity [Laubscher, 1992; Burkhard and Sommaruga, 1998]. It is deemed to be always in a shortening state, according to leveling data [Jouanne et al., 1998] and neotectonic observations [Madritsch et al., 2010]. However, the few GPS data available on the Jura do not show evidence of shortening, but rather a low-magnitude extension parallel to the arc [Walpersdorf et al., 2006]. Moreover, the traditionally accepted assumption of a collisional activity of the Jura raises the question of its geodynamic origin. The Western Alps are themselves in a post-collisional regime and characterized by a noticeable isostatic-related extension, due to the interaction between buoyancy forces and external dynamics [Sue et al., 2007]. Quantitative morphotectonic approaches have been increasingly used in active mountain belts to infer relationship between climates and tectonics in landscape evolution [Whipple, 2009]. In this study, we propose to apply morphometric tools to calcareous bedrock, in a slowly deformed mountain belt. In particular, we have used watersheds metrics determination and associated river profiles analysis to allow quantifying the degree and nature of the equilibrium between the tectonic forcing and the fluvial erosional agent [Kirby and Whipple, 2001]. Indeed, long-term river profiles evolution is controlled by climatic and tectonic forcing through the following expression [Whipple and Tucker, 1999]: S = (U / K) 1/n Am/n (with U: uplift rate, K: empirical erodibility factor, function of hydrological and geological settings; A: drained area, m, n: empirical parameters). We present here a systematic analysis of river profiles applied to the main drainage system of the

  6. Multiple Magmatic Events Over 40 Ma in the Fish Creek Mountains, North-central Great Basin, Nevada, USA

    NASA Astrophysics Data System (ADS)

    Cousens, B.; Henry, C. D.; Stevens, C.; Varve, S.

    2011-12-01

    The Fish Creek Mountains, located in north-central Nevada south of Battle Mountain, is a site of multiple igneous events ranging from ca. 35 Ma to 1 Ma, covering most of the igneous history of the Great Basin of the western United States. Such extended volcanic activity allows for documentation of mantle sources and petrogenetic processes over time. Beginning approximately 50 Ma, the Great Basin experienced a magmatic front that began migrating southwestward across southern Idaho, central Oregon and into northern Nevada and Utah. Intermediate, "arc-like" andesite and dacite dominated volcanic activity in northeastern Nevada between about 45 and 36 Ma. By 34 Ma, a northwest-trending belt of rhyolitic ash-flow calderas began to develop through central Nevada, the "ignimbrite flare-up". Volcanism then migrated westwards towards the Sierra Nevada. In north-central Nevada, the oldest lavas are ca. 35 Ma basaltic andesites through rhyolites that are exposed in the western Shoshone Range, the eastern Tobin Range, and the northern and eastern Fish Creek Mountains. Plagioclase-rich andesites, dacite intrusions, and volcanic breccias occur in a belt along the western side of the Fish Creek Mountains. The bulk of the Fish Creek Mountains is composed of the 24.7 Ma Fish Creek Mountains rhyolitic tuff that is largely confined to an undeformed caldera structure. The caldera and tuff are anomalously young compared to nearby felsic centers such as the Caetano caldera (33.8Ma) and Shoshone Range (39-35 Ma) and relative to the southwest to west magmatic migration. The basal tuff is unwelded, with abundant pumice and lithic (primarily volcanic) fragments but only rare crystals. Sanidine and smoky quartz phenocrysts become more abundant upsection and glassy fiamme (hydrated to devitrified) are common, but the abundance of lithic fragments diminishes. 16-15 Ma volcanic rocks of the Northern Nevada Rift are exposed in the Battle Mountain area, ranging in composition from subalkaine

  7. Cross-strike Discontinuities in the Moine Thrust Belt of NW Scotland; their identity, tectonic significance, and visualisation.

    NASA Astrophysics Data System (ADS)

    Kelly, Michael; Kearsey, Tim; Leslie, Graham; Ritchie, Calum; Krabbendam, Maarten; Williams, Graham

    2013-04-01

    Abrupt lateral changes in thrust geometry occur in many mountain-building fold-and-thrust belts. Whilst many works have dealt with palinspastic reconstructions and transport-direction-parallel balanced cross-sections, far fewer show a full three-dimensional architecture, or examine how these lateral variations in thrust architecture can be linked via so-called 'transverse zones' that serve to demarcate different segments of the thrust belt. When identified, these transverse zones are commonly thought to be related to kinematic responses to irregularities generated across pre-existing, sometimes re-activated, sub-décollement basement faults, contrasts in pre-thrusting cover strata deformation across basement faults, development of duplex structures/antiformal stacks, and/or along-strike variations in mechanical stratigraphy. In many cases however the causative structure is concealed, either by distal parts of the thrust belt or by the foreland basin, and so must be deduced from the overall structural architecture. The amplitude and complexity of the disturbance associated with the transverse zone is typically much greater than amplitude of any irregularity identified in the basement below the thrust belt. In NW Scotland, the classic WNW-vergent Caledonian Moine Thrust Belt (MTB) incorporates a variety of crustal-scale segments. In the Assynt Culmination of the thrust belt, the Traligill Transverse Zone trends sub-parallel to the thrust transport direction, and is associated with an en echelon fault system cutting thrusts, with discontinuity of the thrust and thrust sheet architecture, and with oblique fold and thrust structures. This transverse zone is developed above a basement cross-fault which records repeated brittle reactivation of a Proterozoic shear zone. Thrusting thus deformed a sedimentary sequence that was already disrupted by faults aligned sub-parallel to the thrust transport direction. In the Kinlochewe district where the Loch Maree Fault Zone (LMF

  8. The relative influences of climate and volcanic activity on Holocene lake development inferred from a mountain lake in central Kamchatka

    NASA Astrophysics Data System (ADS)

    Self, A. E.; Klimaschewski, A.; Solovieva, N.; Jones, V. J.; Andrén, E.; Andreev, A. A.; Hammarlund, D.; Brooks, S. J.

    2015-11-01

    A sediment sequence was taken from a closed, high altitude lake (informal name Olive-backed Lake) in the central mountain range of Kamchatka, in the Russian Far East. The sequence was dated by radiocarbon and tephrochronology and used for multi-proxy analyses (chironomids, pollen, diatoms). Although the evolution of Beringian climate through the Holocene is primarily driven by global forcing mechanisms, regional controls, such as volcanic activity or vegetation dynamics, lead to a spatial heterogeneous response. This study aims to reconstruct past changes in the aquatic and terrestrial ecosystems and to separate the climate-driven response from a response to regional or localised environmental change. Radiocarbon dates from plant macrophytes gave a basal date of 7800 cal yr BP. Coring terminated in a tephra layer, so sedimentation at the lake started prior to this date, possibly in the early Holocene following local glacier retreat. Initially the catchment vegetation was dominated by Betula and Alnus woodland with a mosaic of open, wet, aquatic and semi-aquatic habitats. Between 7800 and 6000 cal yr BP the diatom-inferred lake water was pH 4.4-5.3 and chironomid and diatom assemblages in the lake were initially dominated by a small number of acidophilic/acid tolerant taxa. The frequency of Pinus pumila (Siberian dwarf pine) pollen increased from 5000 cal yr BP and threshold analysis indicates that P. pumila arrived in the catchment between 4200 and 3000 cal yr BP. Its range expansion was probably mediated by strengthening of the Aleutian Low pressure system and increased winter snowfall. The diatom-inferred pH reconstructions show that after an initial period of low pH, pH gradually increased from 5500 cal yr BP to pH 5.8 at 1500 cal yr BP. This trend of increasing pH through the Holocene is unusual in lake records, but the initially low pH may have resulted directly or indirectly from intense regional volcanic activity during the mid-Holocene. The chironomid

  9. Holocene vegetation and fire history of the mountains of northern Sicily (Italy)

    USGS Publications Warehouse

    Tinner, Willy; Vescovi, Elisa; Van Leeuwen, Jacqueline; Colombaroli, Daniele; Henne, Paul; Kaltenrieder, Petra; Morales-Molino, Cesar; Beffa, Giorgia; Gnaegi, Bettina; Van der Knaap, Pim W O; La Mantia, Tommaso; Pasta, Salvatore

    2016-01-01

    Knowledge about vegetation and fire history of the mountains of Northern Sicily is scanty. We analysed five sites to fill this gap and used terrestrial plant macrofossils to establish robust radiocarbon chronologies. Palynological records from Gorgo Tondo, Gorgo Lungo, Marcato Cixé, Urgo Pietra Giordano and Gorgo Pollicino show that under natural or near natural conditions, deciduous forests (Quercus pubescens, Q. cerris, Fraxinus ornus, Ulmus), that included a substantial portion of evergreen broadleaved species (Q. suber, Q. ilex, Hedera helix), prevailed in the upper meso-mediterranean belt. Mesophilous deciduous and evergreen broadleaved trees (Fagus sylvatica, Ilex aquifolium) dominated in the natural or quasi-natural forests of the oro-mediterranean belt. Forests were repeatedly opened for agricultural purposes. Fire activity was closely associated with farming, providing evidence that burning was a primary land use tool since Neolithic times. Land use and fire activity intensified during the Early Neolithic at 5000 bc, at the onset of the Bronze Age at 2500 bc and at the onset of the Iron Age at 800 bc. Our data and previous studies suggest that the large majority of open land communities in Sicily, from the coastal lowlands to the mountain areas below the thorny-cushion Astragalus belt (ca. 1,800 m a.s.l.), would rapidly develop into forests if land use ceased. Mesophilous Fagus-Ilex forests developed under warm mid Holocene conditions and were resilient to the combined impacts of humans and climate. The past ecology suggests a resilience of these summer-drought adapted communities to climate warming of about 2 °C. Hence, they may be particularly suited to provide heat and drought-adaptedFagus sylvatica ecotypes for maintaining drought-sensitive Central European beech forests under global warming conditions.

  10. Supplemental Performance Analyses for Igneous Activity and Human Intrusion at the Potential High-Level Nuclear Waste Repository at Yucca Mountain

    SciTech Connect

    Swift, P.; Gaither, K.; Freeze, G.; McCord, J.; Kalinich, D.; Saulnier, G.; Statham, W.

    2002-02-26

    The U.S. Department of Energy (DOE) is considering the possible recommendation of a site at Yucca Mountain, Nevada, for the potential development of a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. Consequences of hypothetical disruption of the Yucca Mountain site by igneous activity or human intrusion have been evaluated in the Yucca Mountain Science and Engineering Report (S&ER) (1), which presents technical information supporting the consideration of the possible site recommendation. Since completion of the S&ER, supplemental analyses have examined possible impacts of new information and alternative assumptions on the estimates of the consequences of these events. Specifically, analyses of the consequences of igneous disruption address uncertainty regarding: (1) the impacts of changes in the repository footprint and waste package spacing on the probability of disruption; (2) impacts of alternative assumptions about the appropriat e distribution of future wind speeds to use in the analysis; (3) effects of alternative assumptions about waste particle sizes; and (4) alternative assumptions about the number of waste packages damaged by igneous intrusion; and (5) alternative assumptions about the exposure pathways and the biosphere dose conversion factors used in the analysis. Additional supplemental analyses, supporting the Final Environmental Impact Statement (FEIS), have examined the results for both igneous disruption and human intrusion, recalculated for a receptor group located 18 kilometers (km) from the repository (the location specified in 40 CFR 197), rather than at the 20 km distance used in the S&ER analyses.

  11. [Mountain sickness].

    PubMed

    Bultas, Jan

    2015-01-01

    Mountaineering brings many health risks, one of which is mountain sickness. Its mildest form - acute mountain sickness - is mainly characterized by subjective symptoms (headache, loss of appetite, insomnia, weakness, nausea and rarely also vomiting). Advanced and life-threatening forms are characterized by tissue edema - cerebral or pulmonary high altitude edema. The common denominator of these acute forms is the low oxygen tension leading to hypoxemia and tissue ischemia. Sum of maladaptive or adaptive processes can modify the clinical picture. Underlying mechanisms of the chronic forms of pulmonary disease are the adaptation processes - pulmonary hypertension and polycythemia leading to heart failure.The only causal therapeutic intervention is to restore adequate oxygen tension, descend to lower altitudes or oxygen therapy. Pharmacotherapy has only a supportive effect. The prophylaxis includes stimulation of the respiratory center by carbonic anhydrase inhibitors (acetazolamide) antiedematous treatment with glucocorticoids (dexamethasone), increase lymphatic drainage of the lungs and brain by β2-agonists (salmeterol) or mitigation of pulmonary hypertension by calcium channel blockers or phosphodiesterase-5 inhibitors (sildenafil or tadalafil). PMID:26750624

  12. Geomorphic terranes of the central Klamath Mountains: Applications to ecosystem management

    SciTech Connect

    De La Fuente, J.; Biery, E.; Creasy, M.; Elder, D.; Haessig, P.; Laurent, T.; Snavely, W. )

    1993-04-01

    Five geomorphic terranes have been identified in the Dillon Mountain area, about 20 miles southwest of Happy Camp, California. These terranes are defined as lands with similar geologic histories, where modern geomorphic processes are similar, and where soils and biotic communities are similar. They include: (1) slump/earthflow terrane; (2) glacial deposit terrane; (3) mountain slope terrane; (4) headwall terrane (steep, fan-shaped headwaters of first order drainages); and (5) inner gorge terrane (the steep landform which develops adjacent to rapidly downcutting streams). These primary geomorphic terranes are further subdivided on a basis of lithology, slope gradient, and geomorphic setting. Geomorphic terrane maps are derived from primary data layers in a geographic information system (GIS). The primary data layers include field-generated lithology, structure, and geomorphology. Slope gradient information is also used, and is derived from digital terrain data, modified by field observations. The distribution of geomorphic terranes is strongly influenced by local stratigraphy, which includes portions of the Western Jurassic Belt (Galice Formation), and the Western Paleozoic and Triassic Belt (Rattlesnake Creek, and Hayfork terranes). Tectonic and climatic events of the Pleistocene Epoch also played a major role in the formation and distribution of geomorphic terranes. These included rapid uplift, seismic activity, and alternating glacial and interglacial conditions. Work is underway to refine the geomorphic terranes by applying other variables such as bedrock structure, precipitation zones, and elevation zones.

  13. 30 CFR 75.1727 - Drive belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drive belts. 75.1727 Section 75.1727 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1727 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing...

  14. 30 CFR 75.1727 - Drive belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drive belts. 75.1727 Section 75.1727 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1727 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing...

  15. 14 CFR 31.63 - Safety belts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Safety belts. 31.63 Section 31.63... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.63 Safety belts. (a) There must be a safety belt... installed, the belt, harness, or other restraining means and its supporting structure must meet the...

  16. 14 CFR 31.63 - Safety belts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Safety belts. 31.63 Section 31.63... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.63 Safety belts. (a) There must be a safety belt... installed, the belt, harness, or other restraining means and its supporting structure must meet the...

  17. 14 CFR 31.63 - Safety belts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Safety belts. 31.63 Section 31.63... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.63 Safety belts. (a) There must be a safety belt... installed, the belt, harness, or other restraining means and its supporting structure must meet the...

  18. 30 CFR 75.1727 - Drive belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drive belts. 75.1727 Section 75.1727 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1727 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing...

  19. 30 CFR 75.1727 - Drive belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drive belts. 75.1727 Section 75.1727 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1727 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing...

  20. 14 CFR 31.63 - Safety belts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Safety belts. 31.63 Section 31.63... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.63 Safety belts. (a) There must be a safety belt... installed, the belt, harness, or other restraining means and its supporting structure must meet the...

  1. 30 CFR 75.1727 - Drive belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drive belts. 75.1727 Section 75.1727 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1727 Drive belts. (a) Drive belts shall not be shifted while in motion unless the machines are provided with mechanical shifters. (b) Belt dressing...

  2. Investigation of a new type charging belt

    SciTech Connect

    Jones, N.L.

    1994-12-31

    There are many desirable characteristics for an electrostatic accelerator charging belt. An attempt has been made to find a belt that improves on these properties over the stock belt. Results of the search, procurement, and 1,500 hours of operational experience with a substantially different belt are reported.

  3. Impact of soil characteristics on piping activity in a mountainous area under a temperate climate (Polish Bieszczady Mts., Eastern Carpathians)

    NASA Astrophysics Data System (ADS)

    Bernatek, Anita; Kacprzak, Andrzej; Stolarczyk, Mateusz

    2015-04-01

    Piping leads to the formation of subsurface channels (pipes) by concentrated flowing water, which may result in the collapse of soil surface and formation of discontinuous gullies. The significance of piping in gully erosion with the recognition of favourable soil properties is widely described in badlands with dispersive materials and in loess-covered hilly regions. Piping conditions in other regions - without dispersive materials or without loess - draw hardly any attention. Therefore, this research aims at a better understanding of the role of soil characteristics in piping activity in a mountainous area with Flysch-derived soils under a temperate climate. The survey was carried out in the Tyskowa catchment, in the Polish Bieszczady Mts. (Eastern Carpathians), where pipes develop at a depth ranging from 0.70 to 1.30 m. We focused on soil characteristics that can impact erodibility, including particle size distribution, structure, consistency, and bulk density. These characteristics as well as selected chemical properties (pH, exchangeable cations, sodium absorption ratio - SAR) were studied in detail for 4 soil profiles with a different position in relation to collapsed pipes (CPs): on a slope with abundant CPs and on one lacking CPs, in the axis of a pipe (above it) and in a piping sinkhole. We tested a hypothesis that soil properties control the occurrence of pipes and we checked if there is any difference in soil properties on slopes with and without CPs. Moreover, we compared soil profiles within the slope with CPs. As to the hypothesis, no clear difference in soils characteristics was observed between the slope with high piping activity and the one without it. At both sites typical Cambisols profiles were developed with high clay-silt content (% silt: mean A=60, standard deviation SD=6.55; % clay: A=27, SD=8.07), which potentially enhances piping. However, the profiles at the site above CPs (in the axis of a pipe, where potentially a pipe will develop) and

  4. Evaluation of Silurian-Niagaran reef belt in Northeastern Michigan

    SciTech Connect

    Aminian, K.; Ameri, S.; Bomar, R.M.

    1987-12-01

    Silurian pinnacle reefs have remained the main exploration targets in the Michigan basin over the last decade. Recent discoveries have extended the reef belt into new areas in the western and northeastern parts of Michigan's lower peninsula. Meanwhile, the exploration for these reefs has continued in more developed areas of the belt in northern Michigan, southwestern Ontario, and southern Michigan. The results of exploration activities in northeastern Michigan in Cheboygan, Montmorency, and Presque Isle counties is different from the rest of the northern portion of the belt. A detailed study used the data available from the exploration activities in this area to determine the reef belt characteristics and reserves potential in northeastern Michigan and its extension into Lake Huron. The results indicated some interesting features, including the narrowing of the belt as it approaches Lake Huron. It was concluded that the different depositional environment during the Silurian Age had affected the development of the belt and the hydrocarbon accumulation in the pinnacle reefs in this part of the basin.

  5. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All...

  6. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... belt assembly that conforms to Federal Motor Vehicle Safety Standard No. 209 1 (§ 571.209) installed...

  7. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... belt assembly that conforms to Federal Motor Vehicle Safety Standard No. 209 1 (§ 571.209) installed...

  8. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All...

  9. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All...

  10. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All...

  11. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... belt assembly that conforms to Federal Motor Vehicle Safety Standard No. 209 1 (§ 571.209) installed...

  12. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All...

  13. 49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Seats, seat belt assemblies, and seat belt... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses... belt assembly that conforms to Federal Motor Vehicle Safety Standard No. 209 1 (§ 571.209) installed...

  14. Chaos on the conveyor belt.

    PubMed

    Sándor, Bulcsú; Járai-Szabó, Ferenc; Tél, Tamás; Néda, Zoltán

    2013-04-01

    The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by a spring to an external static point and, due to the dragging effect of the belt, the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can be achieved only by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic, dynamics and phase transition-like behavior. Noise-induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks (around five). PMID:23679502

  15. Previously Undetected Radiation Belt Revealed

    NASA Video Gallery

    Since their discovery over 50 years ago, the Earth'€™s Van Allen radiation belts have been considered to consist of two distinct zones of trapped, highly energetic charged particles. Observations f...

  16. The earth's trapped radiation belts

    NASA Technical Reports Server (NTRS)

    Noll, R. B.; Mcelroy, M. B.

    1975-01-01

    The near-earth charged particle environment is discussed in terms of spacecraft design criteria. Models are presented of the trapped radiation belts and based on in-situ data obtained from spacecraft.

  17. Archaean greenstone belt tectonism and basin development: some insights from the Barberton and Pietersburg greenstone belts, Kaapvaal Craton, South Africa

    NASA Astrophysics Data System (ADS)

    de Wit, Maarten J.

    The sediments in two of South Africa's major Archaean greenstone belts, the Barberton and Pietersburg greenstone belts, span an age range of some 800 million years. Both greenstone belts represent remnants of extensive fold and thrust belts with complex, but different polyphase tectonic histories. The oldest sediments were deposited between circa 3470 and 3490 M.a. on oceanic like crust preserved in the Barberton belt, possibly at the same time as sedimentation on similar oceanic crust preserved in the Pietersburg belt. Thereafter, the geologic evolution of these two belts diverged considerably. In the Barberton belt, there is clear evidence that the oceanic crust and sediments were obducted onto an intra-arc basin environment within 50 million years of its formation. The sequence was later further imbricated by northwest directed thrust stacking between 3300-3200 M.a. Basin development during both periods of thrusting took place in close proximity to active "calc-alkaline" arc systems. Deformation of the sediments within these basins took place while the same sediments were being deposited. Sedimentation took place predominantly in subaqueous environments, ranging from submarine mid-fans below the photic zone to tidal flats and deltaic plains. The sediments represent a polyhistory successor-type basin: early basins developed along a complex subduction related plate boundary; these basins later evolved into foreland depositories along and within collisional environments of an accretionary orogen. Late in the history of the Barberton greenstone belt (circa 3100 M.a.), the rocks were in places thermally reactivated and probably subjected to extensional processes; these processes overlapped in time with the main episodes of economic gold mineralization, and are of "early Witwatersrand-basin" age. The oceanic-like crust (including associated sediments) preserved in the Pietersburg belt was not significantly deformed until at least 500 million years after its formation

  18. Luminescence ages for alluvial-fan deposits in Southern Death Valley: Implications for climate-driven sedimentation along a tectonically active mountain front

    USGS Publications Warehouse

    Sohn, M.F.; Mahan, S.A.; Knott, J.R.; Bowman, D.D.

    2007-01-01

    Controversy exists over whether alluvial-fan sedimentation along tectonically active mountain fronts is driven by climatic changes or tectonics. Knowing the age of sedimentation is the key to understanding the relationship between sedimentation and its cause. Alluvial-fan deposits in Death Valley and throughout the arid southwestern United States have long been the subjects of study, but their ages have generally eluded researchers until recently. Most mapping efforts have recognized at least four major relative-age groupings (Q1 (oldest), Q2, Q3, and Q4 (youngest)), using observed changes in surface soils and morphology, relation to the drainage net, and development of desert pavement. Obtaining numerical age determinations for these morphologic stages has proven challenging. We report the first optically stimulated luminescence (OSL) ages for three of these four stages deposited within alluvial-fans along the tectonically active Black Mountains of Death Valley. Deposits showing distinct, remnant bar and swale topography (Q3b) have OSL ages from 7 to 4 ka., whereas those with moderate to poorly developed desert pavement and located farther above the active channel (Q3a) have OSL ages from 17 to 11 ka. Geomorphically older deposits with well-developed desert pavement (Q2d) have OSL ages ???25 ka. Using this OSL-based chronology, we note that alluvial-fan deposition along this tectonically active mountain front corresponds to both wet-to-dry and dry-to-wet climate changes recorded globally and regionally. These findings underscore the influence of climate change on alluvial fan deposition in arid and semi-arid regions. ?? 2007 Elsevier Ltd and INQUA.

  19. Correlation of the Klamath Mountains and Sierra Nevada

    USGS Publications Warehouse

    Irwin, William P.

    2003-01-01

    . The sequence shown for the Klamath Mountains is modified from Irwin and Mankinen (1998) and Irwin and Wooden (1999). The episodes are named for the accreting terranes of the Klamath Mountains, but those names may not be suitable for reference to the correlative episodes of the Sierra Nevada. In the figure for each episode, a heavy black line represents the active suture that separated oceanic crustal rocks on the left from the earlier accreted terranes on the right. Plutons are particularly useful for timing the accretionary episodes. The preaccretionary plutons, which commonly represent the roots of oceanic volcanic arcs, are shown in the accreting oceanic crustal rocks to the left of the heavy black line. The accretionary plutons consist of rock that has been subducted and remobilized as magma during the accretionary process and injected into an overlying earlier accreted terrane on the right of the heavy black line. Thus, isotopic dating of the accretionary plutons (preferably U/Pb dates measured on zircon extracted from the plutonic rock) provides a useful basis for assigning ages to the accretionary episodes. Many plutons are rootless at depth, as they tend to be truncated by the subduction zone sutures of younger accreting terranes. Volcanic deposits resulting from accretionary episodes apparently are uncommon except for those deposited on the backstop terranes. In the Klamath Mountains, the Eastern Klamath terrane, which consists of the Yreka, Trinity and Redding subterranes, was the backstop for the Central Metamorphic and younger accretionary episodes, and displays a remarkable record of sedimentation, volcanism and plutonism from Silurian-Devonian to Jurassic time. In the Sierra Nevada, the correlative backstop was the Northern Sierra terrane which shows a similar long record of volcanism in the Taylorsville, Permian, and Jurassic volcanic arc sequences. During some accretionary episodes the subducting oceanic rocks were dynamically metamorphosed to schist

  20. Saturn's North Temperate Belt

    NASA Technical Reports Server (NTRS)

    1981-01-01

    In this Voyager 2 false-color photograph, obtained Aug. 20 from a distance of 6.4 million kilometers (4 million miles), north is to the upper left. This view of the northern edge of Saturn's North Temperate Belt, the brownish region in the lower right of the image, was made from frames taken through violet, blue and green filters. The bright disturbance in the lower left has been coiled into a figure '6' by the wind shear in the planet's atmosphere; this same feature was seen in an earlier release (P-23912, S-2-9). To the south of it, winds blow westward at 20 meters-per-second (45 mph). Within the white zone to the north, wind speeds are in excess of 130 meters-per-second (290 mph) to the east. Wavelike structures can be seen along the ribbon feature that roughly follows the core of this strong eastward-flowing jet. The smallest observable features in this image are about 120 km. (75 mi.) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.

  1. Copious Volcanism on a Compression-dominated Planet? Insights into Magma Ascent and Mountain Building on Io from Numerical Modeling

    NASA Astrophysics Data System (ADS)

    McGovern, Patrick J.; Kirchoff, M. R.

    2012-10-01

    Jupiter's moon Io is the most volcanically active body in the solar system. However, the largest mountains on Io are not massive shield volcanoes, but rather tabular features with a characteristic tilted-block morphology created by compressional faulting. A global bias towards compression may be produced by a vertical “conveyor belt” of repeated burial and subsidence of volcanic units, but this hypothesis begs the question of how the magma ascends to the surface in apparent violation of the long-standing principle that compression inhibits eruption. Here we explore the twin paradoxes of “copious volcanism on a compression-dominated planet” and “dominance of compression-built mountains on a volcanic planet” via quantitative modeling of the evolution of stresses in and deformation of Io’s lithosphere. Consideration of the pressure balance on a vertical magma conduit (dike) reveals that the vertical stress gradient associated with the conveyor belt stress state (compression decreasing upward) actually provides a driving force for magma ascent. Unfortunately, the components of the conveyor belt stress state (thermal, Poisson, and subsidence stresses) add together to produce horizontal compression in the lower lithosphere. This is inconsistent with vertical conduits, instead favoring horizontal ones (sills). However, the combined flexural (bending) and membrane (stretching) responses to loading produce stress changes beneath and surrounding large loads that can alter the principal stress orientations, re-enabling magma ascent. The particle-based Distinct Element Method (DEM) provides another way to model the response of Io’s lithosphere to the conveyor belt stress state. We model the lithosphere as a gravitationally loaded and bonded assemblage of particles, subject to horizontal displacements that increase with depth. The resulting deformation produces intact triangular blocks with tilted margins that resemble Ionian mountains. This work is sponsored by

  2. The Radiation Belt Storm Probes Mission: Advancing Our Understanding of the Earth's Radiation Belts

    NASA Technical Reports Server (NTRS)

    Sibeck, David; Kanekal, Shrikanth; Kessel, Ramona; Fox, Nicola; Mauk, Barry

    2012-01-01

    We describe NASA's Radiation Belt Storm Probe (RBSP) mission, whose primary science objective is to understand, ideally to the point of predictability, the dynamics of relativistic electrons and penetrating ions in the Earth's radiation belts resulting from variable solar activity. The overarching scientific questions addressed include: 1. the physical processes that produce radiation belt enhancement events, 2. the dominant mechanisms for relativistic electron loss, and 3. how the ring current and other geomagnetic processes affect radiation belt behavior. The RBSP mission comprises two spacecraft which will be launched during Fall 2012 into low inclination lapping equatorial orbits. The orbit periods are about 9 hours, with perigee altitudes and apogee radial distances of 600 km and 5.8 RE respectively. During the two-year primary mission, the spacecraft orbits precess once around the Earth and lap each other twice in each local time quadrant. The spacecraft are each equipped with identical comprehensive instrumentation packages to measure, electrons, ions and wave electric and magnetic fields. We provide an overview of the RBSP mission, onboard instrumentation and science prospects and invite scientific collaboration.

  3. Impact of late Cenozoic extension on Laramide overthrust belt and Diablo Platform margins, northwestern Trans-Pecos Texas

    SciTech Connect

    Collins, E.W.; Raney, J.A. )

    1994-03-01

    Late Cenozoic basins and normal faults were superimposed upon preexisting Tertiary, Mesozoic and older structures of northwestern Trans-Pecos Texas. We analyzed the structural and stratigraphic framework of the region using borehole, seismic, outcrop, and aerial-photograph interpretations; regional cross sections were prepared to record Mesozoic and Cenozoic structural attributes. Laramide thrusting displaced Cretaceous rocks northeastward and produced northwest-trending thrust faults and related normal faults, folds, and monoclines. Cenozoic extension caused normal faulting that produced northwest- and north-northwest-trending, 3 to 30 mile-wide fault-bounded basins and adjacent mountain ranges. Tectonism continues to the present. The pre-late Cenozoic structural grain has at least partly controlled geometries of the late Cenozoic basins and associated faults. The deepest Cenozoic basin of this area developed along the leading edge of the Laramide thrust belt and the southwest margin of the Diablo Plateau, and has as much as 9800 ft of Cenozoic basin fill. The most active Quaternary faults vertically displace middle Pleistocene deposits by about 33 to 105 ft. The 56-mi-long Red Light Bolson, containing more than a 2000 ft of Cenozoic deposits, also formed near the leading edge of the older thrust belt. A northwest-striking Quaternary fault zone bounds this basin on its east margin. Two series of Cenozoic basins also have formed northeast of the overthrust belt. The 50-mi-long Eagle Flat-Green River basin system consists of three basins that contain 900 to more than 2000 ft of basin fill. Late Tertiary-Quaternary tectonism has not been as active there as in the other large basins. The 124-mi-long Salt Basin graben system comprises five basins and marks the east edge of Quaternary faulting in this region. Cenozoic fill is more than 2000 ft thick, and the most active Quaternary faults vertically displace middle Pleistocene deposits by at least 13 to 36 ft.

  4. Oil generation in overthrust belts

    SciTech Connect

    Angevine, C.L.; Turcotte, D.L.

    1983-02-01

    The burial of immature sediments beneath a thrust sheet may result in sufficient heating to generate hydrocarbons. The authors present a model for the thermally activated generation of oil from kerogen and the subsequent destruction of the oil through cracking. Using this oil generation model in conjunction with a model applicable to the thermal evolution of overthrust belts, the evolution is studied of oil in sediments beneath a thrust sheet composed of sedimentary rocks. Oil generation may begin soon after emplacement of the thrust sheet. Beneath thick thrust sheets (>8 km), all oil in the sedimentary section may be destroyed less than 5 m.y. after thrusting. The authors results to the timing of oil generation in the sedimentary section beneath the Absaroka thrust plate in the Fossil syncline of western Wyoming. Calculations indicate that the Paleozoic and a part of the Mesozoic section were thermally mature prior to emplacement of the Absaroka plate. The remaining part of Mesozoic sediments matured only after thrusting. The results are in agreement with Warner's 1980 observations that oil being produced from reservoirs in the Absaroka plate was generated in the underthrust Mesozoic section.

  5. Sequence of thrusting and syntectonic sedimentation in the eastern Sub-Atlas thrust belt (Dadès and Mgoun valleys, Morocco)

    NASA Astrophysics Data System (ADS)

    Tesón, Eliseo; Teixell, Antonio

    2008-02-01

    A series of balanced cross-sections across the Sub-Atlas thrust belt and the northern Ouarzazate basin are used to illustrate the structural geometry and the timing of deformation at the southern front of the High Atlas Mountains of Morocco. The selected area is among the best sedimentary records of mountain building of the entire orogenic system. The study of the relationships between thrusts and synorogenic continental formations enables the unraveling of kinematic sequences and the proposal of a relative chronology of deformation. Active thrusting in the area occurred in a rather continuous fashion from the Oligocene to the Pliocene, punctuated by a major erosional phase imprecisely placed in late Oligocene to early Miocene times. Detrital sedimentary facies indicate that uplift in the hinterland of the High Atlas, to the north of the Sub-Atlas belt, was taking place already by mid Eocene times, although it might have commenced locally even earlier. Within the Sub-Atlas zone, the exposed faults did not propagate in a simple piggy-back fashion but show evidence of a complex, synchronous sequence with events of fault reactivation and out-of-sequence thrusting.

  6. The Role of Plasma in Radiation Belt Loss.

    NASA Astrophysics Data System (ADS)

    Jahn, J. M.; Bonnell, J. W.; Kurth, W. S.; Millan, R. M.; Goldstein, J.; Jaynes, A. N.; Blake, J. B.; Denton, R. E.

    2015-12-01

    The radiation belts are zones of relativistic electrons encircling the Earth. Their radial structure is controlled by the competition between source and loss processes. Most commonly, a two-belt structure prevails, though a more complicated three-belt structure - an inner belt plus two outer electron belts - have repeatedly been observed. The plasma conditions that enable and enhance loss-facilitating wave activity in the inner magnetosphere are still under discussion. Relativistic electrons have been thought to more easily resonate with electromagnetic ion-cyclotron waves (EMIC) when the total plasma density is large (i.e., in the plasmasphere and plume). However, there is evidence that this interaction may be not as strong as thought, and that instead the field-aligned motion of lower energy ring current ions (up to a few 10's keV) may play a key role. Similarly, the exact influence of large heavy ion (O+) concentrations remains unsettled. We use 2.5+ years of Van Allen Probes observations to study the region of plasmasphere-outer belt overlap (and its vicinity). By now, the Van Allen Probes provide a complete and very dense coverage of the complete magnetosphere inside geosynchronous orbit We focus our interest on understanding the plasma conditions that can favor EMIC wave growth. We investigate the temperature anisotropy A (modified by plasma β) of the warm/hot plasma, and contrast it with the location specifics of the plasmasphere (i.e., very high total density) and the occurrence of high O+ concentrations in the overlap regions with the radiation belt(s). We present both average conditions for all parameters during a variety of geomagnetic conditions, and highlight specific loss and overlap events in an effort to establish favorable plasma conditions for relativistic electron loss during those times.

  7. Belt conveyors for bulk materials. 6th ed.

    SciTech Connect

    2007-07-01

    The 16 chapters are entitled: Belt conveyor general applications economics; Design considerations; Characteristics and conveyability of bulk materials; Capacities, belt widths and speeds; Belt conveyor idlers; Belt tension and power engineering; Belt selection; Pulleys and shafts; Curves; Steep angle conveying; Belt cleaners and accessories; Transfer points; Conveyor motor drives and controls; Operation, maintenance and safety; Belt takeups; and Emerging technologies. 6 apps.

  8. What can we learn from fluvial incision in high mountains?

    NASA Astrophysics Data System (ADS)

    Fuchs, Margret; Gloaguen, Richard; Krbetschek, Matthias

    2013-04-01

    High and actively deforming mountain ranges attract the attention of geoscientists as they provide natural laboratories of fast evolving process-response systems. Tectonic compressional settings, often linked to perpendicular extension, control the topographic growth and hence, erosion, transport pathways and sedimentation. High altitude differences within short horizontal distances promote material re-organisation and high rates of surface processes. Furthermore, high mountains constitute orographic barriers that affect atmospheric circulations as well as host different climate regimes similar to those of widely separated latitudinal belts. Both cause a high sensitivity of surface processes to changes in climatic conditions. However, feedbacks between climatic and tectonic forcing are complex. Additionally, the dominance of one or the other varies in space and also over time, inheriting various traces of the paleo-morphodynamic conditions to the subsequent process regimes. To unravel the forces driving the evolution of relief in active mountains, numerous studies employ the drainage network of the corresponding mountains as a proxy of landscape evolution. Especially the rates of river incision provide a powerful tool to characterize the surface response and infer causes behind it. Several parameters of river incision are available to describe the fluvial incision at individual sites (e.g. terrace incision rates), along the river course (e.g. longitudinal river profiles, Hack index) and in its perpendicular dimension (e.g. valley cross sections, valley shape ratios). But they require careful interpretation. They are sensitive to both, climatic and tectonic forcing. Therefore, the synopsis of such indices for fluvial incision is essential to evaluate the role of climatic versus tectonic forcing. Here, we use the Panj river system, the major river draining the Pamir mountains of Central Asia, as an example. The Panj experiences high altitude changes of more than 4000

  9. 2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE SEEN THROUGH SWITCHYARD IN BACKGROUND. 165MM LENS. - Eagle Mountain Pump Plant, Ten miles north of Route 10, southeast of Eagle Mountain, Eagle Mountain, Riverside County, CA

  10. Anti-Atlas Mountains, Morocco

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Anti-Atlas Mountains of northern Africa and the nearby Atlas mountains were created by the prolonged collision of the African and Eurasian tectonic plates, beginning about 80 million years ago. Massive sandstone and limestone layers have been crumpled and uplifted more than 4,000 meters in the High Atlas and to lower elevations in the Anti-Atlas. Between more continuous major fold structures, such as the Jbel Ouarkziz in the southwestern Anti-Atlas, tighter secondary folds (arrow) have developed. Earlier, the supercontinent of Pangea rifted apart to form precursors to the Mediterranean and the Atlantic Ocean (Beauchamp and others, 1996). In those seas sands, clays, limey sediments, and evaporite layers (gypsum, rock salt) were deposited. Later, during the mountain-building plate collision, the gypsum layers flowed under the pressure and provided a slippery surface on which overlying rigid rocks could glide (Burkhard, 2001). The broad, open style of folds seen in this view is common where evaporites are involved in the deformation. Other examples can be found in the Southern Zagros of Iran and the Sierra Madre Oriental of Mexico. Information Sources: Beauchamp, W., Barazangi, M., Demnati, A., and El Alji, M., 1996, Intracontinental rifting and inversion: Missour Basin and Atlas Mountains, Morocco: Tulsa, American Association of Petroleum Geologists Bulletin, v. 80, No. 9, p. 1459-1482. Burkhard, Martin, 2001, Tectonics of the Anti-Atlas of Morocco -- Thin-skin/thick-skin relationships in an atypical foreland fold belt. University of Neuchatel, Switzerland: http://www-geol.unine.ch/Structural/Antiatlas.html (accessed 1/29/02). STS108-711-25 was taken in December, 2001 by the crew of Space Shuttle mission 108 using a Hasselblad camera with 250-mm lens. The image is provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography

  11. Petroleum occurrences associated with Uinta mountains, Utah and Colorado

    SciTech Connect

    Osmond, J.C.

    1984-07-01

    The Uinta Mountains in northeastern Utah and northwestern Colorado are among the rare major structures in the western United States with east-west trends. The east-west trend may have an ancestry in a Precambrian aulacogen and a lower Paleozoic arch. The area was quiescent until the Paleocene or Eocene when the mountain block began to rise and the basins on the trending arches formed during the Cretaceous, and it uplifted the belt of Sevier-Laramide overthrusts. The eastern part of the mountain block collapsed during the mid-Tertiary. The range is an anticline with a core of Precambrian metasediments and steeply dipping Paleozoic and Mesozoic rocks on the flanks. Tertiary debris from the mountains overlaps onto older rocks. Anticlines along the flanks of the mountains produce oil and gas from Paleozoic and Mesozoic rocks. Stratigraphic traps on the structures cut by the mountain block are enhanced by the intersection, and they produce from Cretaceous and Tertiary rocks. Uplift of the mountains was important in creating unconformity and stratigraphic traps in several oil and gas fields and in bituminous sand deposits. Geophysical work and drilling have shown the flanks of the mountains to be thrust over or to overhand the adjacent basins. The numerous structural intersections, overhanging flanks, and the facies changes caused by the Uinta Mountains provide good opportunities for continued exploration and success.

  12. Response to"Analysis of the Treatment, by the U.S. Department of Energy, of the FEP Hydrothermal Activity in the Yucca Mountain Performance Assessment" by Yuri Dublyansky

    SciTech Connect

    Houseworth, J.E.; Hardin, E.

    2008-11-17

    This paper presents a rebuttal to Dublyansky (2007), which misrepresents technical issues associated with hydrothermal activity at the proposed Yucca Mountain nuclear waste repository and their importance to the long-term performance of the repository. In this paper, questions associated with hydrothermal activity are reviewed and the justification for exclusion of hydrothermal activity from performance assessment is presented. The hypothesis that hydrothermal upwelling into the present-day unsaturated zone has occurred at Yucca Mountain is refuted by the unambiguous evidence that secondary minerals and fluid inclusions in the unsaturated zone formed in an unsaturated environment from downward percolating meteoric waters. The thermal history at Yucca Mountain, inferred from fluid inclusion and isotopic data, is explained in terms of the tectonic extensional environment and associated silicic magmatism. The waning of tectonic extension over millions of years has led to the present-day heat flux in the Yucca Mountain region that is below average for the Great Basin. The long time scales of tectonic processes are such that any effects of a resumption of extension or silicic magmatism on hydrothermal activity at Yucca Mountain over the 10,000-year regulatory period would be negligible. The conclusion that hydrothermal activity was incorrectly excluded from performance assessment as asserted in Dublyansky (2007) is contradicted by the available technical and regulatory information.

  13. Recent drought induced increase of non-photosynthetically active vegetation cover in the aspen forests of southern Rocky Mountain

    NASA Astrophysics Data System (ADS)

    Huang, C.; Anderegg, W.

    2011-12-01

    Severe droughts in concert with rising temperatures have triggered widespread of forest mortality across multiple tree species worldwide. Tree die-off would produce a significant amount of additional non-photosynthetically active vegetation (NPV), which is the major source of carbon (C) emissions to ecosystems. Trembling aspen (Populus tremuloides) is the most widely distributed tree species in North America and arguably among the largest known organisms in the world, reaching 6000 Mg in a single clone and storing a substantial amount of C in the system. A recent widespread aspen forest mortality (known as sudden aspen decline [SAD]) occurred in the last decade and its ramifications on C cycles of aspen forests and the impact on regional C budgets are not well known. Here we carry out a landscape scale assessment of NPV dynamics across 1186 km2 of aspen forests in southwestern Colorado, USA, which suffered some of the most severe forest biomass loss of the continent. We compared time-series (2000 [the pre-drought condition], 2002 [the driest period] and 2009 [the current condition]) projected NPV derived from summer Landsat Thematic Mapper (TM) images using an automated, probability based spectral mixture analysis model (AutoMCU) with aid from contemporary in-situ field observations conducted in 2009 and 2010. We found that SAD produced 40.3% more of NPV cover comparing to the pre-drought condition (mean ± standard deviation = 23.0 ± 15.8% in 2000 and 32.3 ± 19.0% in 2002) due to the senescence of top canopy aspen leaves that equated to additional 110.3 km2 of NPV cover increase in the region during the driest period. This NPV "ramp-up" also resulted in 22% decrease of green vegetation (mean ± standard deviation = 65.7 ± 18.0% in 2000 and 50.1 ± 18.8% in 2002) and 9.7% increase of visible albedo (3.7 ± 2.4% in 2000 and 4.1 ± 2.3% in 2002), which were also computed from TM images using AutoMCU and a Landsat-based albedo model, respectively. These rapid

  14. Chemical composition, antioxidant properties and antimicrobial activity of the essential oil of Murraya paniculata leaves from the mountains of Central Cuba.

    PubMed

    Rodríguez, Elisa Jorge; Ramis-Ramos, Guillermo; Heyden, Yvan Vander; Simó-Alfonso, Ernesto F; Lerma-García, María Jesús; Saucedo-Hernández, Yanelis; Monteagudo, Urbano; Morales, Yeni; Holgado, Beatriz; Herrero-Martínez, José Manuel

    2012-11-01

    The essential oil of Murraya paniculata L leaves from the mountains of the Central Region of Cuba, obtained by hydrodistillation, was analyzed by gas chromatography-mass spectrometry. Eighteen compounds, accounting for 95.1% of the oil were identified. The major component was beta-caryophyllene (ca. 30%). The antioxidant activity of essential oil was evaluated against Cucurbita seed oil by peroxide, thiobarbituric acid and p-anisidine methods. The essential oil showed stronger antioxidant activity than that of butylated hydroxyanisole and butylated hydroxytoluene, but lower than that of propyl gallate. Moreover, this antioxidant activity was supported by the complementary antioxidant assay in the linoleic acid system and 2, 2'-diphenyl-1-picrylhydrazyl. The essential oil also showed good to moderate inhibitory effects against Klebsiellapneumoniae and Bacillus subtilis. PMID:23285823

  15. Effects of vehicle seat and belt geometry on belt fit for children with and without belt positioning booster seats.

    PubMed

    Reed, Matthew P; Ebert-Hamilton, Sheila M; Klinich, Kathleen D; Manary, Miriam A; Rupp, Jonathan D

    2013-01-01

    A laboratory study was conducted to quantify the effects of belt-positioning boosters on lap and shoulder belt fit. Postures and belt fit were measured for forty-four boys and girls ages 5-12 in four highback boosters, one backless booster, and on a vehicle seat without a booster. Belt anchorage locations were varied over a wide range. Seat cushion angle, seat back angle, and seat cushion length were varied in the no-booster conditions. All boosters produced better mean lap belt fit than was observed in the no-booster condition, but the differences among boosters were relatively large. With one midrange belt configuration, the lap belt was not fully below the anterior-superior iliac spine (ASIS) landmark on the front of the pelvis for 89% of children in one booster, and 75% of children failed to achieve that level of belt fit in another. In contrast, the lap belt was fully below the ASIS for all but two children in the best-performing booster. Child body size had a statistically significant but relatively small effect on lap belt fit. The largest children sitting without a booster had approximately the same lap belt fit as the smallest children experienced in the worst-performing booster. Increasing lap belt angle relative to horizontal produced significantly better lap belt fit in the no-booster condition, but the boosters isolated the children from the effects of lap belt angles. Reducing seat cushion length in the no-booster condition improved lap belt fit but changing cushion angle did not. Belt upper anchorage (D-ring) location had a strong effect on shoulder belt fit in conditions without shoulder belt routing from the booster. Unexpectedly, the worst average shoulder belt fit was observed in one highback booster with a poorly positioned shoulder belt routing clip. The shoulder belt was routed more outboard, on average, with a backless booster than without a booster, but raising the child also amplified the effect of D-ring location, such that children were

  16. Silurian-Niagaran reef belt of the Michigan basin: an update

    SciTech Connect

    Aninian, K.; Bomar, R.M.

    1984-09-01

    Exploration of Silurian-Niagaran pinnacle reefs is discussed. Recent discoveries have extended the reef belt into new areas in the western and northeastern parts of Michigan's lower peninsula, and the results of exploration in the northeastern part of the reef belt indicate that some reef characteristics in that area are not similar to those of the rest of the belt. This required a more detailed study, based on recent data available from the drilling activity in the area, to update the reserves potential and the reef belt extension into Lake Huron.

  17. Volcanic Hazards Survey in the Trans Mexican Volcanic Belt

    NASA Technical Reports Server (NTRS)

    Abrams, Michael; Siebe, Claus; Macias, Jose Luis

    1996-01-01

    We have assembled a digital mosaic of 11 Landsat Thematic images to serve as a mapping base for reconnaissance activities within the Trans Mexican Volcanic Belt. This will aid us in interpretation and in the evaluation of potential activity of all the volcanic centers there. One result is a volcanic hazards map of the area.

  18. Apparatus for forming drive belts

    NASA Technical Reports Server (NTRS)

    Topits, A., Jr. (Inventor)

    1974-01-01

    An apparatus for manufacturing belts, such as seamless belts, is provided, the apparatus has relatively movable rollers that are mounted in an oven. A belt blank, for example, of a thin polyester film, is rotated on the rollers as heat is applied. Four rollers, each mounted on a separate roller assembly, are movable along appropriate tracks while a fifth centrally located roller is stationary. A pair of dc motors are operatively connected to a speed reduction gear assembly to provide a pair of rotating drive shafts that extend into the oven. One rotating shaft drives all of the rollers through a rotational gear assembly while the other drive shaft is capable of positioning the movable rollers through respective rotating threaded shafts. Control devices are provided for controlling the motors while measuring devices are operatively connected to the positional drive shaft to indicate the position of the rollers.

  19. Launching jets from accretion belts

    NASA Astrophysics Data System (ADS)

    Schreier, Ron; Soker, Noam

    2016-05-01

    We propose that sub-Keplerian accretion belts around stars might launch jets. The sub-Keplerian inflow does not form a rotationally supported accretion disk, but it rather reaches the accreting object from a wide solid angle. The basic ingredients of the flow are a turbulent region where the accretion belt interacts with the accreting object via a shear layer, and two avoidance regions on the poles where the accretion rate is very low. A dynamo that is developed in the shear layer amplifies magnetic fields to high values. It is likely that the amplified magnetic fields form polar outflows from the avoidance regions. Our speculative belt-launched jets model has implications on a rich variety of astrophysical objects, from the removal of common envelopes to the explosion of core collapse supernovae by jittering jets.

  20. Active mountain building and the distribution of “core” Maxillariinae species in tropical Mexico and Central America

    USGS Publications Warehouse

    Kirby, Stephen H.

    2011-01-01

    The observation that southeastern Central America is a hotspot for orchid diversity has long been known and confirmed by recent systematic studies and checklists. An analysis of the geographic and elevation distribution demonstrates that the most widespread species of “core” Maxillariinae are all adapted to life near sea level, whereas the most narrowly endemic species are largely distributed in wet highland environments. Drier, hotter lowland gaps exist between these cordilleras and evidently restrict the dispersal of the species adapted to wetter, cooler conditions. Among the recent generic realignments of “core” Maxillariinae based on molecular phylogenetics, the Camaridium clade is easily the most prominent genus in Central America and is largely restricted to the highlands of Costa Rica and Panama, indicating that this region is the ancestral home of this genus and that its dispersal limits are drier, lowland cordilleran gaps. The mountains of Costa Rica and Panama are among the geologically youngest topographic features in the Neotropics, reflecting the complex and dynamic interactions of numerous tectonic plates. From consideration of the available geological evidence, I conclude that the rapid growth of the mountain ranges in Costa Rica and Panama during the late Cenozoic times created, in turn, very rapid ranges in ecological life zones and geographic isolation in that part of the isthmus. Thus, I suggest that these recent geologic events were the primary drivers for accelerated orchid evolution in southeastern Central America.

  1. Dendrogeomorphic reconstruction of Little Ice Age paraglacial activity in the vicinity of the Homathko Icefield, British Columbia Coast Mountains, Canada

    NASA Astrophysics Data System (ADS)

    Hart, Sarah J.; Clague, John J.; Smith, Dan J.

    2010-09-01

    Moraine and glacier dams bordering the Homathko Icefield in the southern British Columbia Coast Mountains failed in the 1980s and 1990s, causing catastrophic downstream floods. The largest of the floods occurred in August 1997 and was caused by overtopping and rapid breaching of the moraine dam that impounds Queen Bess Lake. The floodwaters from Queen Bess Lake eroded Holocene-age sedimentary deposits along the west fork of Nostetuko River and caused a steep rise in the hydrograph of Homathko River at the head of Bute Inlet, ˜ 115 km downstream. A field investigation of the eroded valley fill in 2008, revealed multiple paraglacial valley-fill units, many of which are capped by in situ stumps and woody detritus. Dendrogeomorphological field techniques were employed to develop a chronology for the buried forests. A regional tree-ring chronology spanning the interval CE 1572-2007 was constructed from living subalpine fir ( Abies lasiocarpa) trees at seven sites in the southern Coast Mountains. In cases where subfossil stumps and boles predated the regional chronology, relative death dates constrained by radiocarbon ages were assigned to floating chronologies. By combining these dendrogeomorphological dating methods, we identified six floodplain aggradation episodes within the past 1200 years. Comparison to local and regional glacial histories suggests that these events reflect climate-induced Little Ice Age changes in local glacier cover.

  2. Petrology and structure of Pwemain to Jurassic rocks near Yreka, Klamath Mountains, California

    NASA Astrophysics Data System (ADS)

    Mortimer, N.

    Rocks of the western Paleozoic and Triasic Belt (TrPz belt) of Irwin (1966) in the north eastern Klamath Mountains of California can be subdivided into the same lithotectonic units (terranes) recognized in the southern and central Klamath Mountains. In descending structural order, these are the Fort Jones, North Fork, Salmon River, Havfork and Marble Mountains terranes of Blake and others (1982). Stratigraphic and petrologic regions are consistent with the North Fork, Salmon River and eastern Hayford terranes evolved in close proximity to each other since their origin in Permian time. Faunal and sedimentological evidence suggest that the North Fork terrane was probably at least hundreds of kilometers distant from North America in Permian time, but was close to the continent by early Jurassic time. The structural and metamorphic history of the terranes is consistent with assembly of the TrPz belt in a single, evolving middle and late Jurassic arc/subduction system.

  3. Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization

    NASA Astrophysics Data System (ADS)

    Daglis, I.; Balasis, G.; Bourdarie, S.; Horne, R.; Khotyaintsev, Y.; Mann, I.; Santolik, O.; Turner, D.; Anastasiadis, A.; Georgiou, M.; Giannakis, O.; Papadimitriou, C.; Ropokis, G.; Sandberg, I.; Angelopoulos, V.; Glauert, S.; Grison, B., Kersten T.; Kolmasova, I.; Lazaro, D.; Mella, M.; Ozeke, L.; Usanova, M.

    2013-09-01

    We present the concept, objectives and expected impact of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme. The MAARBLE project employs multi-spacecraft monitoring of the geospace environment, complemented by ground-based monitoring, in order to analyze and assess the physical mechanisms leading to radiation belt particle energization and loss. Particular attention is paid to the role of ULF/VLF waves. A database containing properties of the waves is being created and will be made available to the scientific community. Based on the wave database, a statistical model of the wave activity dependent on the level of geomagnetic activity, solar wind forcing, and magnetospheric region will be developed. Multi-spacecraft particle measurements will be incorporated into data assimilation tools, leading to new understanding of the causal relationships between ULF/VLF waves and radiation belt dynamics. Data assimilation techniques have been proven as a valuable tool in the field of radiation belts, able to guide 'the best' estimate of the state of a complex system. The MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Energization and Loss) collaborative research project has received funding from the European Union’s Seventh Framework Programme (FP7-SPACE-2011-1) under grant agreement no. 284520.

  4. Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

    PubMed

    Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

    2014-03-20

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt. PMID:24646996

  5. Rotationally driven `zebra stripes' in Earth's inner radiation belt

    NASA Astrophysics Data System (ADS)

    Ukhorskiy, A. Y.; Sitnov, M. I.; Mitchell, D. G.; Takahashi, K.; Lanzerotti, L. J.; Mauk, B. H.

    2014-03-01

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected `zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt.

  6. Role of Neogene Exhumation and Sedimentation on Critical-Wedge Kinematics in the Zagros Orogenic Belt, Northeastern Iraq, Kurdistan

    NASA Astrophysics Data System (ADS)

    Koshnaw, R. I.; Horton, B. K.; Stockli, D. F.; Barber, D. E.; Tamar-Agha, M. Y.; Kendall, J. J.

    2014-12-01

    The Zagros orogenic belt and foreland basin formed during the Cenozoic Arabia-Eurasia collision, but the precise histories of shortening and sediment accumulation remain ambiguous, especially at the NW extent of the fold-thrust belt in Iraqi Kurdistan. This region is characterized by well-preserved successions of Cenozoic clastic foreland-basin fill and deformed Paleozoic-Mesozoic hinterland bedrock. The study area provides an excellent opportunity to investigate the linkage between orogenic wedge behavior and surface processes of erosion and deposition. The aim of this research is to test whether the Zagros orogenic wedge advanced steadily under critical to supercritical wedge conditions involving in-sequence thrusting with minimal erosion or propagated intermittently under subcritical condition involving out-of-sequence deformation with intense erosion. These endmember modes of mountain building can be assessed by integrating geo/thermochronologic and basin analyses techniques, including apatite (U-Th)/He thermochronology, detrital zircon U-Pb geochronology, stratigraphic synthesis, and seismic interpretations. Preliminary apatite (U-Th)/He data indicate activation of the Main Zagros Fault (MZF) at ~10 Ma with frontal thrusts initiating at ~8 Ma. However, thermochronometric results from the intervening Mountain Front Flexure (MFF), located between the MZF and the frontal thrusts, suggest rapid exhumation at ~6 Ma. These results suggest that the MFF, represented by the thrust-cored Qaradagh anticline, represents a major episode of out-of-sequence deformation. Detrital zircon U-Pb analyses from the Neogene foreland-basin deposits show continuous sediment derivation from sources to the NNE in Iraq and western Iran, suggesting that out-of-sequence thrusting did not significantly alter sedimentary provenance. Rather, intense hinterland erosion and recycling of older foreland-basin fill dominated sediment delivery to the basin. The irregular distribution of

  7. Radiation Belt Storm Probe Mission Trailer

    NASA Video Gallery

    With launch scheduled for 2012, the Radiation Belt Storm Probe (RBSP) are two identical spacecraft that will investigate the doughnut shaped Van Allen radiation belts, the first discovery of the sp...

  8. Io: Mountains and crustal extension

    NASA Technical Reports Server (NTRS)

    Heath, M. J.

    1985-01-01

    It is argued that there is good reason to conclude that mountains on Io, like those on Earth, are subject to growth and decay. The decay of mountains will be assisted by the ability of SO sub 2 to rot silicate rock and by explosive escape of sub-surface SO sub 2 from aquifers (Haemus Mons is seen to be covered by bright material, presumably fallout from a SO sub 2 rich plume which had been active on the mountain flanks). On the west side of the massif at 10 degrees S, 270 degrees W a rugged surface consists of long ridges running perpendicular to the downslope direction, suggesting tectonic denudation with crustal blocks sliding down the mountain flank. Tectonic denudation may be assisted, as in the case of the Bearpaw Mountains, Montana by overloading mountain flanks with volcanic products. The surfaces of some massifs exhibit a well developed, enigmatic corrugated terrain, consisting of complex ridge systems. Ridges may bifurcate, anastomose to form closed depressions and form concentric loops. Taken together, observations of morphology, heat flux, surface deposits and styles of volcanism may point to the existence of lithosphere domains with distinct compositions and tectonic regimes.

  9. Uplift and denudation rates of an actively growing mountain range inferred from in-situ produced cosmogenic 10Be: the Yumu Shan (NE Tibetan Plateau)

    NASA Astrophysics Data System (ADS)

    Palumbo, L.; Hetzel, R.; Minxing, T.; Li, X.; Guo, J.

    2009-04-01

    Located in the foreland of the Quilian Shan (NE Tibet), the Yumu Shan is an isolated mountain range bounded by an active NW-SE striking thrust fault. Geomorphic and structural features such as fault scarps and wind gaps suggest that the ~70 km long range is actively growing (Hetzel et al., 2004; Tapponnier et al., 1990), hence the tectonic uplift should exceed the rate of denudation. Here we quantify the rate of these two competing processes using in-situ produced cosmogenic 10Be. Catchment-wide denudation rates are derived from 10Be concentrations in stream sediments, whereas rock uplift rates are obtained by combining scarp topographic profiles with dating of geomorphic surfaces deformed by active thrust faults at the Yumu Shan mountain front. Both denudation and rock uplift rates integrate over a similar temporal scale (~10-100 ka) and thus over many earthquake cycles. Our data document that catchment wide-denudation rates vary from ~100 to ~400 mm ka-1 as a function of morphology and lithology, while rock uplift takes place at the rate of ~0.7 mm ka-1. The difference between these values confirms that the Yumu Shan is in a topographic pre-steady state and in accordance with geomorphic and structural features. Tectonic features indicate that over few millions of years the Yumu Shan may rise to a similar height as the main ranges of the Qilian Shan farther south, which have peaks with elevations between ~5 and ~5.5 km. References: Hetzel R., Tao M., Niedermann S., Strecker M.R., Ivy-Ochs S., Kubik P.W., Gao B. (2004). Implications of the fault scaling law for the growth of topography: Mountain ranges in the broken foreland of NE Tibet, Terra Nova, 16, 157-162. Tapponnier P., Meyer B., Avouac J.P., Peltzer G., Gaudemer Y., Guo S., Xiang H., Yin K., Chen Z., Cai S., Dai H. (1990). Active thrusting and folding in the Quilian Shan, and decoupling between upper crust and mantle in northeastern Tibet, Earth Planet. Sci. Lett., 97, 382-403.

  10. Assessing the geomorphological sensitivity of cold climate mountains to climate-driven permafrost degradation: the case of the Russian Altai Mountains

    NASA Astrophysics Data System (ADS)

    Hendrickx, Hanne; Nyssen, Jan; Sannel, Britta; Goossens, Rudi; Lehmkuhl, Frank; Babin, Valery; Bourgeois, Jean; Lanckriet, Sil; Frankl, Amaury

    2016-04-01

    In cold regions, climate change related permafrost thawing is causing geomorphic processes to intensify. This is especially the case in mountain regions, where several studies indicate increased geomorphic activity with the recent thawing of permafrost bodies. In addition to the effect on geomorphic processes, permafrost degradation also results in increased CO2 and CH4 emissions. This causes a positive feedback mechanism on climate change processes. For both the intensity of geomorphic processes and rate of greenhouse gas (GHG) emissions, little information exists for mountain areas in the permafrost belt worldwide. The Russian Altai Mountains are marginally glaciated and house sporadic and discontinuous permafrost. Due to global warming, temperature and precipitation are changing rapidly in the area, at rates higher than the global average. This result in highly dynamic environmental processes, making the Altai Mountains a potential area to understand the interrelations between geomorphology and permafrost, as influenced by climate change. Due to its marginal nature, permafrost degradation is rapid in the Russian Altai Mountains, and related geomorphological processes (e.g. landslides) are therefore accelerating. Therefore, a geomorphological time-depth analysis will be done focusing on geomorphic permafrost indicators such as rock glaciers, solifluction, permafrost creep, polygon patterned ground, palsas and thermokarst. Mapping the present day situation will be based on fieldwork, existing maps, satellite imagery and ASTER Digital Elevation Models. A specific geomorphological map representing the (peri)glacial geomorphology of the 1960s based on CORONA images will be prepared. In addition, 3D-photomodelling of rock glaciers and solifluction lobes will reveal short-term geomorphic dynamics. To understand the permafrost dynamics (1960s-2100) of the area, a statistical-empirical permafrost model will be used, using topo-climatic factors and temperature data from

  11. Overthrust belt status and outlook

    SciTech Connect

    Trushenski, S.P.

    1983-01-01

    Since 1974 the Overthrust Belt has stimulated the imaginations of many major oil companies and independents because of a series of significant oil and gas discoveries in SW. Wyoming and NE. Utah. Intensive exploration and development continues to this day. The specifics of some of the key discoveries are discussed.

  12. Grinding Glass Disks On A Belt Sander

    NASA Technical Reports Server (NTRS)

    Lyons, James J., III

    1995-01-01

    Small machine attached to table-top belt sander makes possible to use belt sander to grind glass disk quickly to specified diameter within tolerance of about plus or minus 0.002 in. Intended to be used in place of production-shop glass grinder. Held on driveshaft by vacuum, glass disk rotated while periphery ground by continuous sanding belt.

  13. Appendiceal transection associated with seat belt restraint

    PubMed Central

    Go, Seung Je; Ye, Jin Bong; Kim, Joong Suck

    2016-01-01

    The seat belt is designed for safety in a motor vehicle and should be worn to prevent severe injuries. But, the seat belt itself can be an injury factor in combination with deceleration forces applied to fixation points of mobile viscera. Here, we present a 23-year-man with traumatic transection of the appendix, highly mobile viscera, following seat belt injury. PMID:27478816

  14. 46 CFR 169.723 - Safety belts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch...

  15. 36 CFR 4.15 - Safety belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened...

  16. 46 CFR 169.723 - Safety belts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch...

  17. 30 CFR 77.1107 - Belt conveyors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to...

  18. 36 CFR 1004.15 - Safety belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Safety belts. 1004.15 Section... belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in the area administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at...

  19. 36 CFR 4.15 - Safety belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened...

  20. 30 CFR 77.1107 - Belt conveyors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to...

  1. Appendiceal transection associated with seat belt restraint.

    PubMed

    Go, Seung Je; Sul, Young Hoon; Ye, Jin Bong; Kim, Joong Suck

    2016-08-01

    The seat belt is designed for safety in a motor vehicle and should be worn to prevent severe injuries. But, the seat belt itself can be an injury factor in combination with deceleration forces applied to fixation points of mobile viscera. Here, we present a 23-year-man with traumatic transection of the appendix, highly mobile viscera, following seat belt injury. PMID:27478816

  2. 36 CFR 4.15 - Safety belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened...

  3. 36 CFR 1004.15 - Safety belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Safety belts. 1004.15 Section... belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in the area administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at...

  4. 36 CFR 4.15 - Safety belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened...

  5. 36 CFR 1004.15 - Safety belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Safety belts. 1004.15 Section... belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in the area administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at...

  6. 30 CFR 77.1107 - Belt conveyors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to...

  7. 36 CFR 1004.15 - Safety belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Safety belts. 1004.15 Section... belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in the area administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at...

  8. 30 CFR 77.1107 - Belt conveyors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to...

  9. 46 CFR 169.723 - Safety belts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch...

  10. 36 CFR 4.15 - Safety belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened...

  11. 46 CFR 169.723 - Safety belts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch...

  12. 46 CFR 169.723 - Safety belts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch...

  13. 30 CFR 77.1107 - Belt conveyors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to...

  14. 36 CFR 1004.15 - Safety belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Safety belts. 1004.15 Section... belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in the area administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at...

  15. Landscape, Mountain Worship and Astronomy in Socaire

    NASA Astrophysics Data System (ADS)

    Moyano, Ricardo

    The spatiotemporal analysis of mountain worship in the indigenous community of Socaire, Atacama, northern Chile, relates to cultural, geographical, climatic, psychological, and astronomical information gathered from ethno archaeological studies. We identify a system of offerings to the mountains that incorporates concepts such as ceque (straight line), mayllku (mountain lord or ancestor), and pacha (space and time). Here, the mountains on the visible horizon (Tumisa, Lausa, Chiliques, Ipira, and Miñiques) feature as the fingers on the left hand (PAH Triad). This structure regulates annual activities and rituals and sets the basis for the Socaireños' worldview raised on a humanized landscape.

  16. Deep crustal structures of the Cape Fold Belt, South Africa

    NASA Astrophysics Data System (ADS)

    Weckmann, U.; Ritter, O.; Chen, X.; Tietze, K.; de Wit, M.

    2010-12-01

    Magnetotelluric (MT) soundings along a 100 km segment of the Inkaba yeAfrica Agulhas-Karoo transect through the Cape Fold Belt, South Africa, yield its first electrical conductivity image on a crustal scale. The Cape Fold Belt (CFB) plays an important role to understand the inversion tectonic setting within the accretionary history along the paleo-pacific margin of Gondwana. The MT profile crosses the Swartberg and Outeniqua (Langeberg) mountain ranges, as well as the Oudtshoorn Basin and the Kango and Kaaimans tectonic inliers. Two-dimensional (2D) inversion models of the MT data show generally good correlation with surface geology. We resolve the resistive roots of the both mountain ranges, to depths of approximately 5 and 10 km, respectively. By contrast, the adjacent Kango and Kaaimans inliers are imaged as shallow wedges partly overlain by sediments of the Oudtshoorn Basin and the Pletmos Basin, respectively. The Kango fault has a shallow southward dip, in contrast to more sub-vertical structures south of the Oudtshoorn basin. Based on the conductivity section we estimate the thickness of the Oudtshoorn basin to 2-3 km. A massive conductivity anomaly at a depth of 3-4 km is located in a synclinorium between the anticlinoria of Table Mountain Group rocks in the Swartberg and Outeniqua ranges. From the conductivity image alone we can neither confirm nor rule out the existence of a mega-detachment in the middle crust, as previously suggested. However, if the Kango Fault is rooted in a detachment zone, it is at upper crustal levels.

  17. Beryllium resources of the tin-spodumene belt, North Carolina

    USGS Publications Warehouse

    Griffitts, Wallace R.

    1954-01-01

    Pegmatite dikes in the tin-spodumene belt of North and South Carolina uniformly contain about 0.05 percent BeO. The most abundant minerals in the pegmatite contain from 0. 0001 to 0.01 percent BeO. Beryl, having 12.0 to 12.3 percent BeO, is the only beryllium-rich mineral and contains more than 80 percent of the total beryllium in the rock. Beryl-bearing pegmatite crops out on hillsides near streams that flow through the pegmatite belt. Much of the pegmatite contains spodumene, feldspar, mica, cassiterite, and columbite, as well as beryl, but separating these minerals will require milling. The minable spodumene ore in the Kings Mountain area, above a depth of 300 feet contains about 40,000 tons of beryl, equivalent to 6, 000 tons of BeO, if 80 percent of the BeO is assumed to be in beryl. Other pegmatite in that area contains an additional 238,000 tons of beryl, or 35, 900 tons of BeO. On the basis of the same assumptions the spodumene ore above a depth of 300 feet 1 in the Beaverdam Creek area contains 6, 000 tons of beryl, or 800 tons of BeO, and all other pegmatite in that area contains an additional 13, 000 tons of beryl, or 1, 700 tons of BeO. The entire tin-spodumene belt contains 823, 000 tons of beryl, equivalent to 122,800 tons of BeO. Little beryllium was found in the Piedmont province outside of the tin-spodumene belt.

  18. Low Temperature Paleogene Thermal Evolution of the British Mountains using Apatite U-Th/He Dating, Northern Yukon, Canada

    NASA Astrophysics Data System (ADS)

    Pickering, J. E.; Guest, B.; Schneider, D. A.; Lane, L.

    2014-12-01

    The age and rate of exhumation of the British Mountains is tied to the timing of deformation in the Beaufort Sea, an active site for hydrocarbon exploration. This region contains a large portion of North America's oil and gas reserves. The British Mountains, the eastern extent of the Brooks Range in Alaska, include Paleogene structures that are the onshore portion of the Beaufort fold belt. In the Beaufort Sea, deformation is dominated by thin-skinned folding and thrusting of Paleocene to Oligocene sediments that is sourced from the British Mountains. Onshore, Paleogene deformation overprints multiple older structural events. The low temperature time history of the onshore Paleogene structures will be determined through U-Th/He dating of apatites (AHe). The results will contribute to better understanding of the timing of the maturation and migration of hydrocarbons in the Beaufort Sea. Previous work on the thermal history of northern Yukon and the North Slope of Alaska provides a regional framework for the region's low temperature-time history. These regional studies of the northern Yukon and Alaska yielded Paleocene to Eocene (60Ma - 40Ma) apatite fission track (AFT) cooling ages that progressively young to the north, consistent with geological evidence for northward propagating deformation. The British Mountains consist of Neoproterozoic to early Paleozoic marine sediments that are intruded by scattered Devonian plutons; both rock types will be included in the study. This study aims to improve the understanding of the Paleogene tectonic activity of the British Mountains and the deformation history of the Beaufort fold belt. The two data sets, existing AFT and new AHe results, will be both be included in the interpretation of the study area. We will present AHe data to better constrain the onshore exhumation and deformation rates at low temperatures (~60-90°C). A sampled transect through the British mountains, along the Firth River valley will provide good

  19. [Temporal variations of soil microbial biomass and enzyme activities during the secondary succession of primary broadleaved-Pinus koraiensis forests in Changbai Mountains of Northeast].

    PubMed

    Hu, Song; Zhang, Ying; Shi, Rong-Jiu; Han, Si-Qin; Li, Hui; Xu, Hui

    2013-02-01

    By the method of space-for-time Substitution, and taking the matured (>200 years old) and over-matured (>200 years old) primary broadleaved-Pinus koraiensis forests and, their secondary forests at different succession stages (20-, 30-, 50-, 80-, and 100 years old Betula platphylla forests) in Changbai Mountains of Northeast China as test objects, this paper studied the temporal variations of soil organic carbon, soil microbial biomass, and soil enzyme activities during the secondary succession of primary broadleaved-Pinus koraiensis forests in the Mountains. Under the 20- and 80 years old B. platphylla forests, the soil organic carbon content in humus layer was the highest (154.8 and 154.3 g.kg-1, respectively); while under the matured and over-matured primary broad-leaved-Pinus koraiensis forests, this organic carbon content was relatively low, being 141. 8 and 133. 4 g.kg , respectively. The soil microbial biomass carbon and microbial quotient and the activities of soil cellulase, peroxidase, acid phosphatase, and cellobiase under the 50- and 80 years old B. platphylla forests were the highest, but the activity of soil polyphenol oxidase was the lowest, which revealed that under middle-aged and matured B. platphylla forests, soil organic carbon had a faster turnover rate, and was probably in a stronger accumulation phase. Statistical analysis showed that the soil microbial biomass carbon had significant positive correlations with the soil organic carbon, total nitrogen, and available phosphorus (r = 0.943, 0. 963, and 0.953, respectively; PMID:23705380

  20. Tsunamigenic seismic sources characterization in the Zagros fold and thrust belt. Implications for tsunami threat in the Persian Gulf

    NASA Astrophysics Data System (ADS)

    Álvarez-Gómez, José A.; Martínez Parro, Laura; Aniel-Quiroga, Íñigo; González, Mauricio; Al-Yahyai, Sultan; Martínez, Jara; Méndez, Fernando; Rueda, Ana; Medina, Raul

    2014-05-01

    Although in the recent history of the Persian Gulf there is no register of relevant tsunamis, there are some historical events that could have generated destructive tsunamis and where historical descriptions of flooding are present. In 978, 1008 and 1871 destructive earthquakes occurred in the northern area of the Persian Gulf. These events where greatly felt by the population, killing hundreds of people, and generating flooding according to descriptions. One problem regarding the historical register is the scarce population in the area of the Zagros coast. In the present, the seismic activity of the area is very high, occurring frequently earthquakes of magnitude greater than 6, specially at the southeastern edge of the Zagros. The active Zagros fold-thrust belt lies on the northeastern margin of the Arabian plate, on Precambrian (Pan African) basement. This is a young (Pliocene) fold-thrust belt currently undergoing 10±4 mm yr-1 shortening and thickening as a result of collision of the Arabian and central Iranian plates. As part of the Alpine-Himalayan mountain chain, extends for more than 1500 km in a NW-SE direction from eastern Turkey to the Minab-Zendan-Palami fault system in southern Iran. This belt results from the closure of the Neo-Tethyan ocean due to a northeast-dipping subduction below the Iranian microcontinent. The subsequent collision beginning in the Neogene between the Arabian Plate and the Iranian Block. The orientation of the fold-and-thrust belt changes along the Zagros Zone from NW-SE strikes towards the northwest, to E-W strikes towards the east, in the Strait of Hormuz. The north-south plate convergence is accommodated in the NW of the Zagros by a combination of NW-SE-trending folds and thrusts, and right-lateral motion along NNW-SSE strike-slip faults. This style of strain partitioning is not present in the east of the Zagros, where east-west-oriented thrusts and folds take up the shortening. We used the tectonic mapping of Berberian (1995

  1. The Ross Orogen and Lachlan Fold Belt in Marie Byrd Land, Northern Victoria Land and New Zealand: implication for the tectonic setting of the Lachlan Fold Belt in Antarctica

    USGS Publications Warehouse

    Bradshaw, J.D.

    2007-01-01

    Correlation of the Cambrian Delamerian Orogen of Australia and Ross Orogen of the Transantarctic Mountains widely accepted but the extension of the adjacent Lachlan Orogen into Antarctica is controversial. Outside the main Ross-Delamerian belt, evidence of this orogeny is preserved at Mt Murphy in Marie Byrd Land and the in Takaka Terrane of New Zealand. In all pre-break- configurations of the SW Pacific, these two areas are far removed from the Ross-Delamerian belt. Evidence from conglomerates in the Takaka Terrane, however, shows that in Late Cambrian times it was adjacent to the Ross Orogen. This indicates major tectonic displacements within Gondwana after the Cambrian and before break-up. The Lachlan Orogen formed in an extensional belt in a supra-subduction zone setting and the Cambrian rocks of Marie Byrd Land and New Zealand are interpreted as parts of a rifted continental ribbon on the outboard side of the Lachlan belt.

  2. Tectonics of some Amazonian greenstone belts

    NASA Technical Reports Server (NTRS)

    Gibbs, A. K.

    1986-01-01

    Greenstone belts exposed amid gneisses, granitoid rocks, and less abundant granulites along the northern and eastern margins of the Amazonian Craton yield Trans-Amazonican metamorphic ages of 2.0-2.1 Ga. Early proterozoic belts in the northern region probably originated as ensimatic island arc complexes. The Archean Carajas belt in the southeastern craton probably formed in an extensional basin on older continental basement. That basement contains older Archean belts with pillow basalts and komatiites. Belts of ultramafic rocks warrant investigatijon as possible ophiolites. A discussion follows.

  3. Monitoring ovarian cycle activity via progestagens in urine and feces of female mountain gorillas: A comparison of EIA and LC-MS measurements.

    PubMed

    Habumuremyi, Sosthene; Robbins, Martha M; Fawcett, Katie A; Deschner, Tobias

    2014-02-01

    Understanding the reproductive biology of endangered mountain gorillas (Gorilla beringei beringei) is essential for optimizing conservation strategies, determining any demographic impact of socioecological changes, and providing information for comparative studies of primates. Non-invasive techniques have been used to assess the reproductive function of many primates and the importance of validating the measurements of hormones metabolites is widely recognized because they may vary even within closely related species. To determine if it is possible to non-invasively monitor ovarian activity in wild mountain gorillas, we used enzyme immunoassays (EIA) to quantify both urinary and fecal excretion of immunoreactive pregnanediol-3-glucuronide (iPdG), defined as all metabolites detected by a pregnanediol-3-glucuronide immunoassay (PdG EIA). Simultaneously, we performed the liquid chromatography mass spectrometry (LC-MS) to quantify the excretion of pregnanediol in urine and feces. Samples were analyzed over nine cycles of five females from the habituated gorillas monitored by Karisoke Research Center, Rwanda. As an additional indicator for ovulation timing, estrone conjugates (E1C) were measured in a subset of urine samples. The concentrations of iPdG and pregnanediol measured in the same samples were significantly correlated. Urinary concentrations of iPdG and pregnanediol fluctuated over the menstrual cycle but did not reveal any cyclic pattern, whereas a typical preovulatory urinary E1C surge and postovulatory increases of fecal iPdG and pregnanediol were detected. The luteal peaks of iPdG and pregnanediol levels in feces were on average 2.8 and 7.6 times higher, respectively, than averaged levels in the corresponding follicular phase. The relative number of days with observed matings was higher within the presumed fertile window than in the preceding period. Overall, the results indicate that fecal analysis of iPdG and pregnanediol is suitable for detecting

  4. Tightening the Corn Belt.

    ERIC Educational Resources Information Center

    Trisler, Carmen E.

    1995-01-01

    Presents an activity in which students: identify agricultural crops that are grown in Great Lakes states, understand how global climate change will affect these crops, hypothesize about crops that could replace these, compare the current crops' economic value with projected replacement crops, and analyze the impact of global climate on the…

  5. 33 CFR 142.42 - Safety belts and lifelines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety belts and lifelines. 142.42 Section 142.42 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES WORKPLACE SAFETY AND HEALTH Personal Protective...

  6. Radiation Belt Storm Probes (RBSP) Payload Safety Introduction Briefing

    NASA Technical Reports Server (NTRS)

    Loftin, Chuck; Lampert, Dianna; Herrburger, Eric; Smith, Clay; Hill, Stuart; VonMehlem, Judi

    2008-01-01

    Mission of the Geospace Radiation Belt Storm Probes (RBSP) is: Gain s cientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind.

  7. Deep resistivity structure along the Longmen Mountain fault zone in the eastern Tibetan plateau of China

    NASA Astrophysics Data System (ADS)

    Wang, X.; Zhang, G.; Luo, W.; Luo, H.; Cai, X.; Zhou, Y.; Zhang, W.; Qin, Q.

    2012-12-01

    1.Introduction Many researchers (e.g.,Wang et al.,2009) have proposed the relevant knowledge of tectonic evolution and dynamic characteristics of the Longmen Mountain belt as well as the Songpan-Ganzi and Yangtze blocks in the past few decades, the knowledge of shallow thrust nappe tectonic along the belt has then been generally recognized. It's, however, still difficult to image the deep crust and mantle structures and reveal the dynamic mechanism of the crustal formation under the Longmen Mountain. In this study, we carried out the MT experiments along and across the Longmen mountain region and investigated the relationships between the crust structure and seismic activity basing on the latest MT geological results. 2. Field observations We conducted three MT experiment profiles in the eastern Tibetan Plateau. One is along the Mingshan-Guangyuan profile parallel with the structural direction, and another two profiles (Maqu-Gaoliangzhen and Luqu-Hechuan) perpendicular to the Longmen Mountain fault zone. In this study, we use the conventional magnetotelluric (MT) data combine with the long-period magnetotelluric (LMT) data to observe electromagnetic response. The MT and LMT data was observed by using the V8 instrument and LEMI-417, respectively. 3. Conclusion (1) According to the results of MT inversion, we find that the high concentration of stress process along the Songpan-Ganzi block and the Yangtze block colliding zone might result from the deep crust-mantle tough shear Zone of Longmen Mountain expanded to mid-upper crust, and finally leads to a new rupture. This could be one of the focal mechanisms of the Wenchuan earthquake (Ms 8.0) generating. The deep resistivity structure along the Longmen Mountain fault zone can be divided into southern,middle and northern segments from southwest to northeast. The total resistivity of southern segment is lower than the middle and northern portions. We suggest that the upper crust of the Longmen Mountain, south of Dayi

  8. The Southeast Asian Tin Belt

    NASA Astrophysics Data System (ADS)

    Schwartz, M. O.; Rajah, S. S.; Askury, A. K.; Putthapiban, P.; Djaswadi, S.

    1995-07-01

    The Southeast Asian Tin Belt is a north-south elongate zone 2800 km long and 400 km wide, extending from Burma (Myanmar) and Thailand to Peninsular Malaysia and the Indonesian Tin Islands. Altogether 9.6 million tonnes of tin, equivalent to 54% of the world's tin production is derived from this region. Most of the granitoids in the region can be grouped geographically into elongate provinces or belts, based on petrographic and geochronological features. - The Main Range Granitoid Province in western Peninsular Malaysia, southern Peninsular Thailand and central Thailand is almost entirely made up of biotite granite (184-230 Ma). Tin deposits associated with these granites contributed 55% of the historic tin production of Southeast Asia. - The Northern Granitoid Province in northern Thailand (0.1% of tin production) also has dominant biotite granite (200-269 Ma) but it is distinguished by abundant post-intrusion deformation. - The Eastern Granitoid Province extends from eastern Peninsular Malaysia to eastern Thailand. The Malaysian part is subdivided into the East Coast Belt (220-263 Ma), Boundary Range Belt (197-257 Ma) and Central Belt (79-219 Ma). The granitoids cover a wide compositional range from biotite granite to hornblende-biotite granite/granodiorite and diorite-gabbro. Tin deposits are associated with biotite granite in the East Coast Belt (3% of tin production). The granitoids in the other areas of the Eastern Granitoid Province are barren. - The Western Granitoid Province (22-149 Ma) in northern Peninsular Thailand, western Thailand and Burma has biotite granite and hornblende-biotite granite/granodiorite. Tin deposits are associated with biotite granite, which probably is the dominant phase (14% of tin production). The granitoids of the Indonesian Tin Islands (193-251 Ma) do not permit grouping into geographically distinct units. Main Range-type and Eastern Province-type plutons occur next to each other. Most of the tin deposits are associated with Main

  9. Chemistry of water collected from an unventilated drift, Yucca Mountain, Nevada

    USGS Publications Warehouse

    Marshall, B.D.; Oliver, T.A.; Peterman, Z.E.

    2007-01-01

    Water samples (referred to as puddle water samples) were collected from the surfaces of a conveyor belt and plastic sheeting in the unventilated portion of the Enhanced Characterization of the Repository Block (ECRB) Cross Drift in 2003 and 2005 at Yucca Mountain, Nevada. The chemistry of these puddle water samples is very different than that of pore water samples from borehole cores in the same region of the Cross Drift or than seepage water samples collected from the Exploratory Studies Facility tunnel in 2005. The origin of the puddle water is condensation on surfaces of introduced materials and its chemistry is dominated by components of the introduced materials. Large CO2 concentrations may be indicative of localized chemical conditions induced by biologic activity. ?? 2007 Materials Research Society.

  10. Chemistry of Water Collected From an Unventilated Drift, Yucca Mountain, Nevada

    SciTech Connect

    Marshall, Brian D.; Peterman, Zell E.

    2007-07-01

    Water samples (referred to as puddle water samples) were collected from the surfaces of a conveyor belt and plastic sheeting in the unventilated portion of the Enhanced Characterization of the Repository Block (ECRB) Cross Drift in 2003 and 2005 at Yucca Mountain, Nevada. The chemistry of these puddle water samples is very different than that of pore water samples from borehole cores in the same region of the Cross Drift or than seepage water samples collected from the Exploratory Studies Facility tunnel in 2005. The origin of the puddle water is condensation on surfaces of introduced materials and its chemistry is dominated by components of the introduced materials. Large CO{sub 2} concentrations may be indicative of localized chemical conditions induced by biologic activity. (authors)

  11. Possible uranium mineralization, Mineral Mountains, Utah

    USGS Publications Warehouse

    Miller, W. Roger; McHugh, John B.; Ficklin, Walter H.

    1979-01-01

    The Mineral Mountains block in west-central Utah is a horst whose core stands structurally high relative to all nearby basin-and-range fault blocks. Rocks of the Mineral Mountains range from Precambrian to Quaternary in age, but mostly consist of Tertiary granitic rocks. The range lies with the Wah Wah-Tusher mineral belt. Lead, silver, gold, and tungsten have been mined commercially. During a geochemical survey conducted in the summer of 1978, 30 water samples and 29 stream-sediment samples were collected from the Mineral Mountains area. The interpretation of simple plots of uranium concentrations and the results of a Q-mode factor analysis indicate that potential exists for uranium mineral deposits within the Mineral Mountains. The most favorable areas are in the granitic pluton near its contacts with sedimentary and metamorphic rocks. The most likely source of the uranium anomalies is uraninite-bearing epigenic veins along faults and fractures within the pluton. Three hypothetical models are proposed to account for the uranium mineralization.

  12. Mantle peridotite xenoliths in andesite lava at El Peñon, central Mexican Volcanic Belt: Isotopic and trace element evidence for melting and metasomatism in the mantle wedge beneath an active arc

    NASA Astrophysics Data System (ADS)

    Mukasa, Samuel B.; Blatter, Dawnika L.; Andronikov, Alexandre V.

    2007-08-01

    Peridotites in the mantle wedge and components added to them from the subducting slab are thought to be the source of most arc magmas. However, direct sampling of these materials, which provides a glimpse into the upper mantle beneath an active margin, is exceedingly rare. In the few arc localities where found, peridotite xenoliths are usually brought to the surface by basaltic magmas. Remarkably, the hornblende-bearing ultramafic xenoliths and clinopyroxene megaxenocrysts from El Peñon in the central Mexican Volcanic Belt were brought to the surface by a Quaternary high-Mg siliceous andesite, a rock type usually considered too evolved to be a direct product of mantle melting. The xenoliths and megaxenocrysts from El Peñon represent lithospheric mantle affected by significant subduction of oceanic lithosphere since as early as the Permian. Trace element and radiogenic isotope data we report here on these materials suggest a history of depletion by melt extraction, metasomatism involving a fluid phase, and finally, limited reaction between the ultramafic materials and the host andesite, probably during transport. They also show that high-Mg siliceous andesite can be a direct product of 1-5% melting of H 2O-bearing spinel lherzolite.

  13. Comparing spatial patterns of thrust belt architecture and bedrock river morphology across the southern Bolivian Andes

    NASA Astrophysics Data System (ADS)

    Syrek, J. F.; Barnes, J. B.

    2011-12-01

    Rivers set the pace of mountain landscape evolution, but their ability to incise into rock is often governed by numerous factors. The degree to which variations in lithology, relief, rock uplift rates, and climate may affect the form of channel profiles remain largely open questions. Empirical models of bedrock river incision, such as stream power (E = KAmSn), oversimplify these potentially important factors. For example, the influence of many factors such as channel geometry, hydraulic roughness, sediment flux, and substrate erodibility are combined into the coefficient of erosion, K. Here we investigate the spatial patterns of rock erodibility, bedrock river slope, concavity, and stream power-based estimates of incision across the southern Bolivian Andes. We hypothesize that bedrock river morphology correlates with the thrust-belt geology. For example, channels cutting through the strongest and least fractured rock units will exhibit the highest steepness values. We estimate rock erodibility by measuring (a) compressive rock strength with a Schmidt hammer and (b) fracture density from exposures proximal to river channels at ~80 total sites from all the major rock units exposed throughout the study area. We use a hydrologically-conditioned 90 m digital elevation model to map patterns of channel steepness (ksn) and concavity (θ) indices. Furthermore, we use the stream power model, combined with a previous local calibration of K, to estimate patterns of river incision along the study area rivers. The combined strength and fracture density measurements suggest the Neogene volcanics, Cretaceous sediments, and Devonian metasediments are the least erodible units and the Silurian and Ordovician metasediments are the weakest. In general, changes in channel steepness often correlate with (1) changes in rock erodibility, (2) high rock uplift rates associated with active structures in the Subandes, and (3) the major hinterland structural transition between the Eastern

  14. Aeromagnetic map and interpretation of geophysical data from the Condrey Mountain Roadless Area, Siskiyou County, California

    USGS Publications Warehouse

    Jachens, R.C.; Elder, W.P.

    1983-01-01

    The western Paleozoic and Triassic belt that nearly surrounds the Condrey Mountain Schist is a melange of sedimentary, volcanic, and ultramafic rocks metamorphosed to amphibolite facies (Coleman and others, 1983). Only two samples of the metamorphic melange were collected near the Condrcy Mountain Road less Area, but extensive sampling of this unit southwest of the roadless area yielded an average sample density of 2.86±0.15 g/cm3 (112 samples) (Jachens and others, 1983).

  15. The Scattered Kuiper Belt Objects

    NASA Astrophysics Data System (ADS)

    Trujillo, C. A.; Jewitt, D. C.; Luu, J. X.

    1999-09-01

    We describe a continuing survey of the Kuiper Belt conducted at the 3.6-m Canada France Hawaii Telescope on Mauna Kea, Hawaii. The survey employs a 12288 x 8192 pixel CCD mosaic to image the sky to red magnitude 24. All detected objects are targeted for systematic follow-up observations, allowing us to determine their orbital characteristics. Three new members of the rare Scattered Kuiper Belt Object class have been identified, bringing the known population of such objects to four. The SKBOs are thought to have been scattered outward by Neptune, and are a potential source of the short-period comets. Using a Maximum Likelihood method, we place observational constraints on the total number and mass of the SKBOs.

  16. Geophysical Evidence for the Tectonic Evolution of the Inverted Belt-Purcell Basin, Northwestern Montana

    NASA Astrophysics Data System (ADS)

    Rutherford, B. S.; Speece, M. A.; Constenius, K. N.

    2015-12-01

    The geometry of the Precambrian Belt-Purcell basin and subsequent allochthon, that dominates the geology of northwestern Montana, played a critical role in the development of compressional structures during orogenesis and their ensuing reactivation during the later phase of extensional collapse. Five reprocessed seismic reflection profiles provide images in the Swan Range and adjacent valleys that we have correlated to published seismic data north into Canada. Reflections from syndepositional sills encased within Lower Belt rocks offer clues to the configuration of the basin prior to its tectonic inversion. Thick basinal facies of the Lewis salient are contrasted by thin shelfal facies found in hanging wall rocks of frontal Belt carrying thrusts south of the salient. The along strike change in hanging wall rocks reflects the original configuration of the Belt basin margin. Rocks of the Lewis salient were deposited in an embayment on the northeastern margin of the Belt basin. Shelfal accumlations of the embayment comprise an autochthonous wedge that has remained in the footwall of the Lewis thrust system. South of the embayment and related salient, nearly the entire Belt basin was detached from pre-Belt crystalline rocks and inverted at the latitude of the Sawtooth Range. Deeply exhumed Phanerozoic rocks of the Sawtooth Range are a direct consequence of the thin wedge geometry of the detached basin south of the Lewis salient that required growth of a substantial orogenic wedge to obtain critical taper values. We offer an alternate interpretation of a >10 km high, west facing décollement ramp that coincides with the Belt-Purcell basin margin. Previous interpretations in Montana have inferred the location of the basin margin ramp to approximate the trace of the Purcell Anticlinorium. Seismic data and cross-section balancing suggest the Rocky Mountain Trench as a more accurate location. Based on our proposed position of the basin margin the Belt-Purcell allocthon

  17. Beyond the Kuiper Belt Edge

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott; Trujillo, Chad

    2012-02-01

    Of the thousands of known objects beyond Neptune, only one has a perihelion significantly beyond 50 AU, Sedna at 75 AU. Kuiper Belt surveys to date have not been optimized to survey beyond the Kuiper Belt edge at 50 AU. Most of these surveys either did not go faint enough, did not have the required long cadence to detect very slow moving objects or covered too small of an area of sky. The dynamical and physical properties of objects in this region offer key constraints on the formation and evolution of our solar system. In order to probe the Sedna like population of objects with moderate radii (100 km) we propose a medium wide-field outer solar system survey. This survey will allow us to determine if the objects beyond 50 AU are fainter than expected, if there is truly a dearth of objects, or if the Kuiper Belt continues again after some sizable gap possibly caused by a planet sized object. We will be able to examine the origin of Sedna and determine if this eccentric, distant body is unique (as once believed for Pluto) or just the first of a new class of object in the outer Solar System.

  18. Beyond the Kuiper Belt Edge

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott

    2012-06-01

    Of the thousands of known objects beyond Neptune, only one has a perihelion significantly beyond 50 AU, Sedna at 75 AU. Kuiper Belt surveys to date have not been optimized to survey beyond the Kuiper Belt edge at 50 AU. Most of these surveys either did not go faint enough, did not have the required long cadence to detect very slow moving objects or covered too small of an area of sky. The dynamical and physical properties of objects in this region offer key constraints on the formation and evolution of our solar system. In order to probe the Sedna like population of objects with moderate radii (100 km) we propose a deep wide-field outer solar system survey. This survey will allow us to determine if the objects beyond 50 AU are fainter than expected, if there is truly a dearth of objects, or if the Kuiper Belt continues again after some sizable gap possibly caused by a planet sized object. We will be able to examine the origin of Sedna and determine if this eccentric, distant body is unique (as once believed for Pluto) or just the first of a new class of object in the outer Solar System. We will also explore the Neptune Trojans and scattered disk populations through the survey.

  19. Liquid belt radiator design study

    NASA Technical Reports Server (NTRS)

    Teagan, W. P.; Fitzgerald, K. F.

    1986-01-01

    The Liquid Belt Radiator (LBR) is an advanced concept developed to meet the needs of anticipated future space missions. A previous study documented the advantages of this concept as a lightweight, easily deployable alternative to present day space heat rejection systems. The technical efforts associated with this study concentrate on refining the concept of the LBR as well as examining the issues of belt dynamics and potential application of the LBR to intermediate and high temperature heat rejection applications. A low temperature point design developed in previous work is updated assuming the use of diffusion pump oil, Santovac-6, as the heat transfer media. Additional analytical and design effort is directed toward determining the impact of interface heat exchanger, fluid bath sealing, and belt drive mechanism designs on system performance and mass. The updated design supports the earlier result by indicating a significant reduction in system specific system mass as compared to heat pipe or pumped fluid radiator concepts currently under consideration (1.3 kg/sq m versus 5 kg/sq m).

  20. Spectroscopy of Kuiper Belt Objects and Centaurs

    NASA Technical Reports Server (NTRS)

    Cruikshank, Dale P.; Brown, Robert H.; Pendleton, Y. J.; Veeder, Glenn J.

    1998-01-01

    Recent near-infrared spectroscopy of Kuiper Belt objects and Centaurs indicates considerable spectral diversity among them. Some have entirely bland spectra with no discernible spectral features (e.g., Chiron), while 5145 Pholus has a very active spectrum with absorption bands of H2O, CH3OH, and probably the mineral olivine present. In addition, the strong red color of Pholus indicates the presence of organic solids. Among the KBOs, 1993 SC has an active spectrum with the probably presence of hydrocarbons and possibly the ices of H2O and N2. The diversity among these spectra and the implications that such diversity has for models of the formation of the formation of the planets will be discussed.

  1. Artifical Mountains: A Synthetic Approach

    ERIC Educational Resources Information Center

    Sipiera, Paul P.; Aumann, John A.

    1974-01-01

    Describes a secondary science unit which uses an urban environment to develop a comparison between naturally formed mountains and man-constructed skyscrapers. The unit is one in a series of fifty laboratory activities designed to stimulate students of earth science by interrelating scientific principles and procedures to a familiar environment.…

  2. Rocky Mountain spotted fever

    MedlinePlus

    Rocky Mountain spotted fever is a disease caused by a type of bacteria carried by ticks. ... Rocky Mountain spotted fever is caused by the bacteria Rickettsia rickettsii (R. Rickettsii) , which is carried by ticks. The ...

  3. Acute mountain sickness

    MedlinePlus

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... Acute mountain sickness is caused by reduced air pressure and lower oxygen levels at high altitudes. The faster you ...

  4. Rocky Mountain spotted fever

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/000654.htm Rocky Mountain spotted fever To use the sharing features on this page, please enable JavaScript. Rocky Mountain spotted fever is a disease caused by a ...

  5. Formation and age of sphalerite mineralization in carbonate rocks of Bajocian age in the Swiss Jura Mountains: evidence of Mesozoic hydrothermal activity

    NASA Astrophysics Data System (ADS)

    Efimenko, Natalia; Schneider, Jens; Spangenberg, Jorge E.; Chiaradia, Massimo; Adatte, Thierry; Föllmi, Karl B.

    2014-06-01

    A combination of petrographic and geochemical techniques was applied to better constrain the origin and evolution of the fluid systems responsible for the formation of disseminated, Cd-rich (up to 0.6 wt%), sphalerite (ZnS) mineralization in the northeastern part of the Jura Mountains, Switzerland. The Rb-Sr ages of sphalerite samples indicate that a main phase of sphalerite formation occurred near the boundary between the late Middle and early Late Jurassic, at around 162 Ma. The negative δ34S values (-22.3 to -5.3 ‰) suggest that biogenic sulfide sulfur was involved in ZnS precipitation. The strontium isotope composition is more radiogenic than that of contemporaneous seawater, reflecting the interaction of mineralizing fluids with silicate rocks. Lead isotope signatures are very uniform (206Pb/204Pb = 18.63-18.67, 207Pb/204Pb = 15.63-15.64, 208Pb/204Pb = 38.51-38.63), indicating an isotopically well-homogenized fluid system. The basement rocks underlying the Jurassic strata are considered to be the main source of metals for the sphalerite mineralization. The migration of deep-sourced hydrothermal saline metal-bearing fluids into the Bajocian host carbonates containing sedimentary reduced sulfur resulted in the precipitation of sulfides. The period of sphalerite formation near the Middle-Late Jurassic boundary is characterized by enhanced tectonic and hydrothermal activity in Europe, related to the opening of the Central Atlantic and tectonic/thermal subsidence during spreading of the Alpine Tethys. Our study provides evidence that the Bajocian carbonate rocks in the Jura Mountains area were affected by the circulation of deep-sourced metal-bearing hydrothermal fluids in response to these continent-wide tectonothermal events. The presence of sphalerite mineralization and associated geochemical anomalies in Zn and Cd contents in carbonate rocks may also be used to trace basement features.

  6. Deep Seismic Reflection Profiles Reveal The Crust Structures Beneath Xing'an-Mongolian Orogenic Belt and Its Neighboring Area

    NASA Astrophysics Data System (ADS)

    Hou, H.; Gao, R.; Keller, R. G.; Li, Q.; Li, W.; Li, H.; Xiong, X.; Guo, L.

    2012-12-01

    high-order NMO, detailed velocity analysis and maximum energy residual static correction, prestack time migration methods, etc. The migrated stack profiles reveal the deep structural and tectonic relationship between the northern margin of the North China craton and the Xing'an-Mongolia orogenic belt. Many curved reflection phases with strong amplitudes beneath the igneous province suggest magma activity obversed. It is notable that a strong Moho reflection appears to be spatially associated with ancient collision or subduction zones exhibits complicated characters. This scenario may suggest multiple tectonic events that are spatially correlated from topgraphy to deep structure. We think the east-dipping reflections beneath the eastside of Great Xing'An Mountain Range within upper crust related with the Mesozoic detachment event in North China. All the profiles provides a rare opportunity to study signatures of ancient orogenic processes in the context of a continental interior. This research is supported by SinoProbe-02, China NSF (No.40830316, No.41104060), China Geological Survey (No.1212011120975), US NSF PIRE grant (0730154).

  7. Response of radiation belt simulations to different radial diffusion coefficients

    NASA Astrophysics Data System (ADS)

    Drozdov, A.; Shprits, Y.; Subbotin, D.; Kellerman, A. C.

    2013-12-01

    Resonant interactions between Ultra Low Frequency (ULF) waves and relativistic electrons may violate the third adiabatic invariant of motion, which produces radial diffusion in the electron radiation belts. This process plays an important role in the formation and structure of the outer electron radiation belt and is important for electron acceleration and losses in that region. Two parameterizations of the resonant wave-particle interaction of electrons with ULF waves in the magnetosphere by Brautigam and Albert [2000] and Ozeke et al. [2012] are evaluated using the Versatile Electron Radiation Belt (VERB) diffusion code to estimate their relative effect on the radiation belt simulation. The period of investigation includes quiet time and storm time geomagnetic activity and is compared to data based on satellite observations. Our calculations take into account wave-particle interactions represented by radial diffusion transport, local acceleration, losses due to pitch-angle diffusion, and mixed diffusion. We show that the results of the 3D diffusion simulations depend on the assumed parametrization of waves. The differences between the simulations and potential missing physical mechanisms are discussed. References Brautigam, D. H., and J. M. Albert (2000), Radial diffusion analysis of outer radiation belt electrons during the October 9, 1990, magnetic storm, J. Geophys. Res., 105(A1), 291-309, doi:10.1029/1999JA900344 Ozeke, L. G., I. R. Mann, K. R. Murphy, I. J. Rae, D. K. Milling, S. R. Elkington, A. A. Chan, and H. J. Singer (2012), ULF wave derived radiation belt radial diffusion coefficients, J. Geophys. Res., 117, A04222, doi:10.1029/2011JA017463.

  8. The Belt voice: Acoustical measurements and esthetic correlates

    NASA Astrophysics Data System (ADS)

    Bounous, Barry Urban

    This dissertation explores the esthetic attributes of the Belt voice through spectral acoustical analysis. The process of understanding the nature and safe practice of Belt is just beginning, whereas the understanding of classical singing is well established. The unique nature of the Belt sound provides difficulties for voice teachers attempting to evaluate the quality and appropriateness of a particular sound or performance. This study attempts to provide answers to the question "does Belt conform to a set of measurable esthetic standards?" In answering this question, this paper expands on a previous study of the esthetic attributes of the classical baritone voice (see "Vocal Beauty", NATS Journal 51,1) which also drew some tentative conclusions about the Belt voice but which had an inadequate sample pool of subjects from which to draw. Further, this study demonstrates that it is possible to scientifically investigate the realm of musical esthetics in the singing voice. It is possible to go beyond the "a trained voice compared to an untrained voice" paradigm when evaluating quantitative vocal parameters and actually investigate what truly beautiful voices do. There are functions of sound energy (measured in dB) transference which may affect the nervous system in predictable ways and which can be measured and associated with esthetics. This study does not show consistency in measurements for absolute beauty (taste) even among belt teachers and researchers but does show some markers with varying degrees of importance which may point to a difference between our cognitive learned response to singing and our emotional, more visceral response to sounds. The markers which are significant in determining vocal beauty are: (1) Vibrancy-Characteristics of vibrato including speed, width, and consistency (low variability). (2) Spectral makeup-Ratio of partial strength above the fundamental to the fundamental. (3) Activity of the voice-The quantity of energy being produced. (4

  9. A Chaos Conveyor Belt

    NASA Astrophysics Data System (ADS)

    Schmidt, Britney E.

    2013-10-01

    A critical question for the habitability of Europa remains: how does the ice shell work? The detection of shallow subsurface lenses below Europa’s chaos implies that the ice shell is recycled rapidly and that Europa may be currently active. While this is not the first time liquid water has been implicated for Europa, the location of these features combined with new perspective on their dynamics frames the question in a new way. Melt lenses are intriguing potential habitats. Moreover, their formation requires the existence of impurities within the upper ice shell that may be sources of energy for microorganisms. Geomorphic evidence also exists for hydraulic redistribution of fluids both vertically and horizontally through pores and fractures. This process, observed in terrestrial ice shelves, may preserve liquid water within the ice matrix over many kilometers from the source. Horizontal transport of material may produce interconnectivity between distinct regions of Europa, thus preserving habitable conditions within the ice over a longer duration. At a surface age of 40-90 Myr, with 25-50% covered by chaos terrain, Europa's resurfacing rate is very high and water likely plays a significant role. Because of the vigor of overturn implied by this new work, it is likely that surface and subsurface materials are well-mixed within the largest and deepest lenses, providing a mechanism for bringing oxidants and other surface contaminants to the deeper ice shell where it can reach the ocean by convective or compositional effects. The timescales over which large lenses refreeze are large compared to the timescales for vertical transport, while the timescales for smaller lenses are comparable to or shorter than convective timescales. Moreover, marine ice accretion at the bottom of the ice shell may be contributing to a compositional buoyancy engine that would change the makeup of the ice shell. From this point of view, we evaluate the habitability of Europa’s ice and

  10. [Effects of grazing disturbance on soil active organic carbon in mountain forest-arid valley ecotone in the upper reaches of Minjiang River].

    PubMed

    Liu, Shan-Shan; Zhang, Xing-Hua; Gong, Yuan-Bo; Li, Yuan; Wang, Yan; Yin, Yan-Jie; Ma, Jin-Song; Guo, Ting

    2014-02-01

    Effects of grazing disturbance on the soil carbon contents and active components in the four vegetations, i.e., artificial Robinia pseudoacacia plantation, artificial poplar plantation, Berberis aggregate shrubland and grassland, were studied in the mountain forest-arid valley ecotone in the upper Minjiang River. Soil organic carbon and active component contents in 0-10 cm soil layer were greater than in 10-20 cm soil layer at each level of grazing disturbance. With increasing the grazing intensity, the total organic carbon (TOC), light fraction organic carbon (LFOC), particulate organic carbon (POC) and easily oxidized carbon (LOC) contents in 0-10 cm soil layer decreased gradually in the artificial R. pseudoacacia plantation. The LFOC content decreased, the POC content increased, and the TOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the artificial poplar plantation. The POC content decreased, and the TOC, LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the B. aggregate shrubland. The POC and TOC contents decreased, and the LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the grassland. The decreasing ranges of LOC, LFOC and POC contents were 0.1-7.9 times more than that of TOC content. There were significant positive relationships between TOC and LOC, LFOC and POC, suggesting that the active organic carbon components could reflect the change of soil total carbon content. PMID:24830233

  11. Tectonic paleostress fields and structural evolution of the NW-Caucasus fold-and-thrust belt from Late Cretaceous to Quaternary

    NASA Astrophysics Data System (ADS)

    Saintot, Aline; Angelier, Jacques

    2002-11-01

    The NW-Caucasus fold-and thrust belt essentially corresponds to the inverted western Flysch Zone of the Great Caucasus Mountains, a deep basin that developed from Late Jurassic to Eocene times between the Scythian Plate to the north and the Transcaucasian terranes to the south (the Shatsky Ridge, SW of the NW-Caucasus zone). The Flysch Basin was strongly affected by compression in Late Eocene times, when the characteristic WNW trending folds and thrusts of the NW-Caucasus belt developed (some authors regard the main compressive deformation as Miocene in age). By means of remote sensing analysis, we elucidate the geometry of major structures in the belt: WNW trending south-vergent thrusts and folds, and major vertical and transverse NNE-SSW to NE-SW deep fault zones. The later structures are interpreted as ancient faults that were active during the development of the Flysch Basin. Paleostress investigations reveal seven main tectonic episodes in the evolution of the NW-Caucasus since Late Cretaceous. Combining structural interpretation, remote sensing analysis and paleostress field reconstruction, we propose a model for the structural evolution of the belt. During the Late Cretaceous-Paleocene, the western Caucasus zone was under transtensional regime with an E-W to NE-SW trending σ3 that generated oblique normal movements along NNE-SSW transverse faults and WNW-ESE margins of the Flysch Basin. This tectonism could correspond to rifting related to the formation of the Eastern Black Sea Basin. At the Paleocene-Eocene boundary, a transpressional event with an E-W to NW-SE trending σ1 developed and the NNE-SSW to NE-SW trending faults could have been inverted. This event could correspond to an attenuation in the Eastern Black Sea Basin formation or to the incipient accretion of the Transcaucasian terranes. During the Eocene, another E-W to NW-SE oblique extension (-transtensional event) affected the Flysch Basin that could be related to a known rifting phase in the

  12. Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization

    NASA Astrophysics Data System (ADS)

    Daglis, I. A.; Bourdarie, S.; Khotyaintsev, Y.; Santolik, O.; Horne, R.; Mann, I.; Turner, D.; Anastasiadis, A.; Angelopoulos, V.; Balasis, G.; Chatzichristou, E.; Cully, C.; Georgiou, M.; Glauert, S.; Grison, B.; Kolmasova, I.; Lazaro, D.; Macusova, E.; Maget, V.; Papadimitriou, C.; Ropokis, G.; Sandberg, I.; Usanova, M.

    2012-09-01

    We present the concept, objectives and expected impact of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme. The MAARBLE project employs multi-spacecraft monitoring of the geospace environment, complemented by ground-based monitoring, in order to analyze and assess the physical mechanisms leading to radiation belt particle energization and loss. Particular attention is paid to the role of ULF/VLF waves. A database containing properties of the waves is being created and will be made available to the scientific community. Based on the wave database, a statistical model of the wave activity dependent on the level of geomagnetic activity, solar wind forcing, and magnetospheric region will be developed. Furthermore, we will incorporate multi-spacecraft particle measurements into data assimilation tools, aiming at a new understanding of the causal relationships between ULF/VLF waves and radiation belt dynamics. Data assimilation techniques have been proven to be a valuable tool in the field of radiation belts, able to guide 'the best' estimate of the state of a complex system.

  13. [Chemical properties and enzyme activities of rhizosphere and non-rhizosphere soils under six Chinese herbal medicines on Mt. Taibai of Qinling Mountains, Northwest China].

    PubMed

    Meng, Ling-Jun; Geng, Zeng-Chao; Yin, Jin-Yan; Wang, Hai-Tao; Ji, Peng-Fei

    2012-10-01

    This paper studied the chemical properties and enzyme activities of rhizosphere and non-rhizosphere soils in different habitats of six Chinese herbal medicines, including Pyrola decorata, Cephalotaxus fortunei, Polygonatum odoratum, Potentilla glabra, Polygonum viviparum, and Potentilla fruticosa, on the Mt. Taibai of Qinling Mountains. In the rhizosphere soils of the herbs, the contents of soil organic matter, total nitrogen, available nitrogen, and available phosphorus and the soil cation exchange capacity (CEC) were higher, presenting an obvious rhizosphere aggregation, and the soil enzyme activities also showed an overall stronger characteristics, compared with those in non-rhizosphere soils. The soil organic matter, total nitrogen, and total phosphorus contents in the rhizosphere soils had significant positive correlations with soil neutral phosphatase activity, and the soil CEC had significant positive correlations with the activities of soil neutral phosphatase and acid phosphatase. In the non-rhizosphere soils, the soil organic matter and total nitrogen contents had significant positive correlations with the activities of soil urease, catalase and neutral phosphatase, and the soil CEC showed a significant positive correlation with the activities of soil urease, catalase, neutral phosphatase and acid phosphatase. The comprehensive fertility level of the rhizosphere soils was higher than that of the non-rhizosphere soils, and the rhizosphere and non-rhizosphere soils of P. fruticosa, P. viviparum, and P. glabra had higher comprehensive fertility level than those of P. decorata, P. odoratum and C. fortunei. In the evaluation of the fertility levels of rhizosphere and non-rhizosphere soils under the six Chinese herbal medicines, soil organic matter content and CEC played important roles, and soil neutral phosphatase could be the preferred soil enzyme indicator. PMID:23359927

  14. In Vitro and In Vivo Antimalarial Activity of Ficus thonningii Blume (Moraceae) and Lophira alata Banks (Ochnaceae), Identified from the Ethnomedicine of the Nigerian Middle Belt

    PubMed Central

    Falade, M. O.; Akinboye, D. O.; Gbotosho, G. O.; Ajaiyeoba, E. O.; Happi, T. C.; Abiodun, O. O.; Oduola, A. M. J.

    2014-01-01

    Drug resistance in Plasmodium falciparum requires that new drugs must be developed. Plants are a potential source for drug discovery and development. Two plants that used to treat febrile illnesses in Nigeria were tested for in vitro and in vivo antimalarial activity and cytotoxicity in cancer cell lines. Methanol, hexane, and ethyl acetate leaf extracts of Ficus thonningii and Lophira alata were active in in vitro assays against P. falciparum NF54 (sensitive) and K1 (multiresistant) strains. Hexane extracts of F. thonningii and L. alata were the most effective extracts in in vitro assays with IC50 of 2.7 ± 1.6 μg/mL and 2.5 ± 0.3 μg/mL for NF54 and 10.4 ± 1.6 μg/mL and 2.5 ± 2.1 μg/mL for K1 strain. All extracts were nontoxic in cytotoxicity assays against KB human cell line with IC50 of over 20 μg/mL, demonstrating selectivity against P. falciparum. In vivo analysis shows that hexane extracts of both plants reduced parasitaemia. At the maximum dose tested, L. alata had a 74.4% reduction of parasitaemia while F. thonningii had a reduction of 84.5%, both extracts prolonged animal survival in mice infected with P. berghei NK65 when compared with vehicle treated controls. The antiplasmodial activity observed justifies the use of both plants in treating febrile conditions. PMID:24955248

  15. Cenozoic post-collisional brittle tectonic history and stress reorientation in the High Zagros Belt (Iran, Fars Province)

    NASA Astrophysics Data System (ADS)

    Navabpour, Payman; Angelier, Jacques; Barrier, Eric

    2007-03-01

    The Zagros fold-and-thrust belt of SW-Iran is among the youngest continental collision zones on Earth. Collision is thought to have occurred in the late Oligocene-early Miocene, followed by continental shortening. The High Zagros Belt (HZB) presents a Neogene imbricate structure that has affected the thick sedimentary cover of the former Arabian continental passive margin. The HZB of interior Fars marks the innermost part of SE-Zagros, trending NW-SE, that is characterised by higher elevation, lack of seismicity, and no evident active crustal shortening with respect to the outer (SW) parts. This study examines the brittle structures that developed during the mountain building process to decipher the history of polyphase deformation and variations in compressive tectonic fields since the onset of collision. Analytic inversion techniques enabled us to determine and separate different brittle tectonic regimes in terms of stress tensors. Various strike-slip, compressional, and tensional stress regimes are thus identified with different stress fields. Brittle tectonic analyses were carried out to reconstruct possible geometrical relationships between different structures and to establish relative chronologies of corresponding stress fields, considering the folding process. Results indicate that in the studied area, the main fold and thrust structure developed in a general compressional stress regime with an average N032° direction of σ1 stress axis during the Miocene. Strike-slip structures were generated under three successive strike-slip stress regimes with different σ1 directions in the early Miocene (N053°), late Miocene-early Pliocene (N026°), and post-Pliocene (N002°), evolving from pre-fold to post-fold faulting. Tensional structures also developed as a function of the evolving stress regimes. Our reconstruction of stress fields suggests an anticlockwise reorientation of the horizontal σ1 axis since the onset of collision and a significant change in

  16. Synchronous and Cogged Fan Belt Performance Assessment

    SciTech Connect

    Cutler, D.; Dean, J.; Acosta, J.

    2014-02-01

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  17. Antiformal closure in ductile and brittle-ductile in fold-and-thrust belt tranverse zones, Moine Thrust Belt, NW Scotland

    NASA Astrophysics Data System (ADS)

    Leslie, G.; Krabbendam, M.

    2009-04-01

    Abrupt lateral changes in thrust geometry occur in many mountain-building fold-and-thrust belts. Such changes in architecture are referred to as so-called transverse zones, and are commonly thought to be related to kinematic responses to irregularities generated across pre-existing, sometimes re-activated, basement faults. In many cases however the causative structure is concealed, either by distal parts of the thrust belt or the foreland basin. Sharp lateral changes in the structural geometry of ductile thrust stacks are less widely studied and reported. In NW Scotland, the classic Caledonian WNW-vergent Moine Thrust Belt exposes excellent examples of the structural architecture in such transverse zones, both in kilometre-scale thick monolithic (meta-)sandstone packages subject to ductile deformation, and in much thinner heterolithic packages subject to brittle-ductile deformation. In both cases the amplitude of the antiformal disturbance associated with the transverse zone is much greater than amplitude of any irregularity identified in the basement below. In Neoproterozoic Moine rocks in the hanging wall of the Moine Thrust, a large-scale lateral culmination wall forms a component part of the Oykel Transverse Zone (OTZ), a kilometre-scale thick constrictional ductile shear zone striking sub-parallel to the WNW-directed thrust transport direction. The OTZ forms the SW limit of the Cassley Culmination. ESE-plunging mullions are an integral part of the fabric of the transverse zone and were generated by constriction sub-parallel to the WNW-directed thrust transport direction. Main folds and fabrics in the transverse zone hanging-wall are folded by main folds and fabrics in the footwall, demonstrating the overall foreland-propagating record of ductile deformation as the Cassley Culmination grew. Constriction and mullion development are attributed to differential, transtensional movement across the transverse zone during the later stages of culmination development

  18. Solar Modulation of Inner Trapped Belt Radiation Dose Rate

    NASA Astrophysics Data System (ADS)

    Diaz, Abel

    2002-03-01

    The two steady sources of radiation in low Earth orbit are the inner trapped-belt and galactic cosmic radiation (GCR), which present a very significant hazard to the astronauts and flight equipment electronics. The fluxes of GCR and inner trapped-belt particles at a fixed altitude are modulated by solar activity. They decrease with increasing solar activity in general. The mechanism of these two sources of radiation are, however, very different. In this project we shall be concerned with modeling the inner trapped-belt protons. The existing trapped-belt models, namely AP-8 is based on data acquired prior to 1970 during solar cycle 20 with relatively low solar flux. These models describe the environment at solar minimum and solar maximum only. Cycles 21 and 22 were much larger, but no valid radiation model exists for such large values. Moreover, the existing models like AP-8, CRRESPRO, and GOST describe the flux to an accuracy of a factor of two to five. There is clear need to accurately predict radiation exposure of astronauts and equipment at all times between the solar minimum and solar maximum, not only on the short duration Space Shuttle flights, but also the longer term stay onboard the International Space Station. In our approach we are taking into account some important parameters, which are responsible for energy losses of protons within the belts. These energy losses are primarily to electrons and by collisions to atmospheric nuclei. Accordingly the atmospheric density dependence at a certain altitude during a specific solar activity is an important parameter that needs to be accurately incorporated into a realistic model. We are involved in developing such a model, which would enable us to predict the radiation exposure for all occasions.

  19. Geophysical interpretations of the Libby thrust belt, northwestern Montana

    USGS Publications Warehouse

    Kleinkopf, M. Dean; with sections by Harrison, Jack Edward; Stanley, W.D.

    1997-01-01

    Interpretations of gravity and aeromagnetic anomaly data, supplemented by results from two seismic reflection profiles and five magnetotelluric soundings, were used to study buried structure and lithology of the Libby thrust belt of northwestern Montana. The gravity anomaly data show a marked correlation with major structures. The Purcell anticlinorium and the Sylvanite anticline are very likely cored by stacks of thrust slices of dense crystalline basement rocks that account for the large gravity highs across these two structures. Gravity anomaly data for the Cabinet Mountains Wilderness show a string of four broad highs. The principal magnetic anomaly sources are igneous intrusive rocks, major fault zones, and magnetite-bearing sedimentary rocks of the Ravalli Group. The most important magnetic anomalies in the principal study area are five distinct positive anomalies associated with Cretaceous or younger cupolas and stocks.

  20. Pelvic Belt Effects on Health Outcomes and Functional Parameters of Patients with Sacroiliac Joint Pain

    PubMed Central

    Hammer, Niels; Möbius, Robert; Schleifenbaum, Stefan; Hammer, Karl-Heinz; Klima, Stefan; Lange, Justin S.; Soisson, Odette; Winkler, Dirk; Milani, Thomas L.

    2015-01-01

    Introduction The sacroiliac joint (SIJ) is a common source of low back pain. However, clinical and functional signs and symptoms correlating with SIJ pain are widely unknown. Pelvic belts are routinely applied to treat SIJ pain but without sound evidence of their pain-relieving effects. This case-control study compares clinical and functional data of SIJ patients and healthy control subjects and evaluates belt effects on SIJ pain. Methods 17 SIJ patients and 17 healthy controls were included in this prospective study. The short-form 36 survey and the numerical rating scale were used to characterize health-related quality of life in patients in a six-week follow-up and the pain-reducing effects of pelvic belts. Electromyography data were obtained from the gluteus maximus, biceps femoris, rectus femoris and medial vastus. Alterations of muscle activity, variability and gait patterns were compared in patients and controls along with the belts’ effects in a dynamic setting when walking. Results Significant improvements were observed in the short-form 36 survey of the SIJ patients, especially in the physical health subscores. Minor declines were also observed in the numerical rating scale on pain. Belt-related changes of muscle activity and variability were similar in patients and controls with one exception: the rectus femoris activity decreased significantly in patients with belt application when walking. Further belt effects include improved cadence and gait velocity in patients and controls. Conclusions Pelvic belts improve health-related quality of life and are potentially attributed to decreased SIJ-related pain. Belt effects include decreased rectus femoris activity in patients and improved postural steadiness during locomotion. Pelvic belts may therefore be considered as a cost-effective and low-risk treatment of SIJ pain. Trial Registration ClinicalTrials.gov NCT02027038 PMID:26305790

  1. Denudation rates of tropical mountain regions : What is the proportion of chemical weathering vs. mechanical denudation in a tectonically active settings?

    NASA Astrophysics Data System (ADS)

    Roelandt, C.; Vanacker, V.; Goddéris, Y.; Kaplan, J. O.

    2009-04-01

    Denudation rates of tropical mountain regions in tectonically active settings, such as the northern Andes, are known to be high. Rivers draining the northern Andes are important sources of sediment and nutrients to the low-lying basins and oceans. The largest part of the total denudation rates in these environments is often considered to be mechanical denudation, given their steep topography, young geology and humid and warm climate. In this study, we try to better understand the linkage between physical denudation and chemical weathering for degraded catchments with shallow, eroded soils. We selected a limited number of case-studies from the Ecuadorian Andes being characterized by humid climate, steep topography, and intensive land use. For these catchments, the total denudation rates are derived from cosmogenic isotope concentrations in riverborne quartz (Vanacker et al, 2007, Geology). The B-WITCH model (Roelandt et al. submitted, GBC) is used to quantify chemical weathering rates. The results of this study will allow us to get a better insight in the linkage between chemical and physical denudation rates for an active tectonic setting. Besides, the data will give the opportunity to explore the effect of land use change on chemical weathering rates.

  2. Workshop on Techtonic Evolution of Greenstone Belts

    NASA Technical Reports Server (NTRS)

    Dewit, M. J. (Editor); Ashwal, Lewis D. (Editor)

    1986-01-01

    Topics addressed include: greenstone belt externalities; boundaries; rock terranes; synthesis and destiny; tectonic evolution; rock components and structure; sedimentology; stratigraphy; volcanism; metamorphism; and geophysics.

  3. Investigation of Moving Belt Radiator Technology Issues

    NASA Technical Reports Server (NTRS)

    Teagan, W. Peter; Aguilar, Jerry L.

    1994-01-01

    The development of an advanced spacecraft radiator technology is reported. The moving belt radiator is a thermal radiator concept with the promise of lower specific mass (per kW rejected) than that afforded by existing technologies. The results of a parametric study to estimate radiator mass for future space power systems is presented. It is shown that this technology can be scaled up to 200 MW for higher rejection temperatures. Several aspects of the design concept are discussed, including the dynamics of a large rotating belt in microgravity. The results of a computer code developed to model the belt dynamics are presented. A series of one-g experiments to investigate the dynamics of small belts is described. A comprehensive test program to investigate belt dynamics in microgravity aboard the NASA KC-135 aircraft is discussed. It was found that the desired circular shape can readily be achieved in microgravity. It is also shown that a rotating belt is stable when subjected to simulated attitude control maneuvers. Heat exchanger design is also investigated. Several sealing concepts were examined experimentally, and are discussed. Overall heat transfer coefficients to the rotating belt are presented. Material properties for various belt materials, including screen meshes, are also presented. The results presented in this report indicate that the moving belt radiator concept is technically feasible.

  4. Safety belt promotion: theory and practice.

    PubMed

    Nelson, G D; Moffit, P B

    1988-02-01

    The purpose of this paper is to provide practitioners a rationale and description of selected theoretically based approaches to safety belt promotion. Theory failure is a threat to the integrity and effectiveness of safety belt promotion. The absence of theory driven programs designed to promote safety belt use is a concern of this paper. Six theoretical models from the social and behavioral sciences are reviewed with suggestions for application to promoting safety belt use and include Theory of Reasoned Action, the Health Belief Model, Fear Arousal, Operant Learning, Social Learning Theory, and Diffusion of Innovations. Guidelines for the selection and utilization of theory are discussed. PMID:3276342

  5. Plight of the Cabinet Mountains grizzlies

    SciTech Connect

    Fischer, H.

    1982-01-01

    The effects of mineral and petroleum exploration and development and logging on grizzly bears in the Cabinet Mountains region of Montana is discussed. The author points out that such activities might cut the bears off from other bear populations in the Glacier National park and the Bob Marshall Wilderness. It is maintained, that in order for the bears to survive, they must range beyond the Cabinet Mountains and that extensive human activities in the area would damage their range. (JMT)

  6. Exhumation history of the Mindoro, Philippine and its implication to mountain building process.

    NASA Astrophysics Data System (ADS)

    Wei, S. C.

    2014-12-01

    Exhumation history of the Mindoro, Philippine and its implication to mountain building process Chung-Wei Shiu1,Yuan-Hsi Lee1, Reuy-juin Rau2, Toto Bacolcol3 Department of Earth and Environmental Sciences, National Chung-Cheng university, Taiwan Department of earth science, National Cheng Kung University, Taiwan Department of science and technology, Philippine institute of volcanology and seismology The Mindoro orogenic belt is result from the collision between the Palawan continental crust and Philippine Mobile zone. In this study we report the zircon fission track ages to identify the timing of rapid exhumation of Mindoro orogenic belt. The NNW striking East Mindoro fault (EMF) separates the mountain belt and Luzon arc block. The highest mountain reaches to 2500m on hanging wall of the EMF. In the western side of the EMF the mountain belt can be separate into two blocks by NW trending Mindoro suture zone. To the north and south are Mindoro block and north Palawan block, respectively. The Mindoro block is major comprised of unmetamorphic Eocene strata and Mindoro metamorphic complex. The oldest zircon reset fission track ages shows 4-5 Ma in eastern and western side of the Mindoro metamorphic complex which infers the timing of rapid exhumation since ca. 5Ma which indicate the timing of collision between the Palawan block and Luzon arc.

  7. Timber Mountain Precipitation Monitoring Station

    SciTech Connect

    Lyles, Brad; McCurdy, Greg; Chapman, Jenny; Miller, Julianne

    2012-01-01

    A precipitation monitoring station was placed on the west flank of Timber Mountain during the year 2010. It is located in an isolated highland area near the western border of the Nevada National Security Site (NNSS), south of Pahute Mesa. The cost of the equipment, permitting, and installation was provided by the Environmental Monitoring Systems Initiative (EMSI) project. Data collection, analysis, and maintenance of the station during fiscal year 2011 was funded by the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office Environmental Restoration, Soils Activity. The station is located near the western headwaters of Forty Mile Wash on the Nevada Test and Training Range (NTTR). Overland flows from precipitation events that occur in the Timber Mountain high elevation area cross several of the contaminated Soils project CAU (Corrective Action Unit) sites located in the Forty Mile Wash watershed. Rain-on-snow events in the early winter and spring around Timber Mountain have contributed to several significant flow events in Forty Mile Wash. The data from the new precipitation gauge at Timber Mountain will provide important information for determining runoff response to precipitation events in this area of the NNSS. Timber Mountain is also a groundwater recharge area, and estimation of recharge from precipitation was important for the EMSI project in determining groundwater flowpaths and designing effective groundwater monitoring for Yucca Mountain. Recharge estimation additionally provides benefit to the Underground Test Area Sub-project analysis of groundwater flow direction and velocity from nuclear test areas on Pahute Mesa. Additionally, this site provides data that has been used during wild fire events and provided a singular monitoring location of the extreme precipitation events during December 2010 (see data section for more details). This letter report provides a summary of the site location, equipment, and data collected in

  8. Structural Discordance Between Neogene Detachments and Frontal Sevier Thrusts, Central Mormon Mountains, Southern Nevada

    NASA Astrophysics Data System (ADS)

    Wernicke, Brian; Walker, J. Douglas; Beaufait, Mark S.

    1985-02-01

    Detailed geologic mapping in the Mormon Mountains of southern Nevada provides significant insight into processes of extensional tectonics developed within older compressional orogens. A newly discovered, WSW-directed low-angle normal fault, the Mormon Peak detachment, juxtaposes the highest levels of the frontal most part of the east-vergent, Mesozoic Sevier thrust belt with autochthonous crystalline basement. Palinspastic analysis suggests that the detachment initially dipped 20-25° to the west and cut discordantly across thrust faults. Nearly complete lateral removal of the hanging wall from the area has exposed a 5 km thick longitudinal cross-section through the thrust belt in the footwall, while highly attenuated remnants of the hanging wall (nowhere more than a few hundred meters thick) structurally veneer the range. The present arched configuration of the detachment resulted in part from progressive "domino-style" rotation of a few degrees while it was active, but is largely due to rotation on younger, structurally lower, basement-penetrating normal faults that initiated at high-angle. The geometry and kinematics of normal faulting in the Mormon Mountains suggest that pre-existing thrust planes are not required for the initiation of low-angle normal faults, and even where closely overlapped by extensional tectonism, need not function as a primary control of detachment geometry. Caution must thus be exercised in interpreting low-angle normal faults of uncertain tectonic heritage such as those seen in the COCORP west-central Utah and BIRP's MOIST deep-reflection profiles. Although thrust fault reactivation has reasonably been shown to be the origin of a very few low-angle normal faults, our results indicate that it may not be as fundamental a component of orogenic architecture as it is now widely perceived to be. We conclude that while in many instances thrust fault reactivation may be both a plausible and attractive hypothesis, it may never be assumed.

  9. Comparing the Response of Birds and Butterflies to Vegetation-Based Mountain Ecotones Using Boundary Detection Approaches

    PubMed Central

    Kent, Rafi; Levanoni, Oded; Banker, Eran; Pe’er, Guy; Kark, Salit

    2013-01-01

    Mountains provide an opportunity to examine changes in biodiversity across environmental gradients and areas of transition (ecotones). Mountain ecotones separate vegetation belts. Here, we aimed to examine whether transition areas for birds and butterflies spatially correspond with ecotones between three previously described altitudinal vegetation belts on Mt. Hermon, northern Israel. These include the Mediterranean Maquis, xero-montane open forest and Tragacanthic mountain steppe vegetation belts. We sampled the abundance of bird and butterfly species in 34 sampling locations along an elevational gradient between 500 and 2200 m. We applied wombling, a boundary-detection technique, which detects rapid changes in a continuous variable, in order to locate the transition areas for bird and butterfly communities and compare the location of these areas with the location of vegetation belts as described in earlier studies of Mt. Hermon. We found some correspondence between the areas of transition of both bird and butterfly communities and the ecotones between vegetation belts. For birds and butterflies, important transitions occurred at the lower vegetation ecotone between Mediterranean maquis and the xero-montane open forest vegetation belts, and between the xero-montane open forest and the mountain steppe Tragacanthic belts. While patterns of species turnover with elevation were similar for birds and butterflies, the change in species richness and diversity with elevation differed substantially between the two taxa. Birds and butterflies responded quite similarly to the elevational gradient and to the shift between vegetation belts in terms of species turnover rates. While the mechanisms generating these patterns may differ, the resulting areas of peak turnover in species show correspondence among three different taxa (plants, birds and butterflies). PMID:23505472

  10. A novel isopimarane diterpenoid with acetylcholinesterase inhibitory activity from Nepeta sorgerae, an endemic species to the Nemrut Mountain.

    PubMed

    Yilmaz, Anil; Cağlar, Pinar; Dirmenci, Tuncay; Gören, Nezhun; Topçu, Gülaçti

    2012-06-01

    From the dichloromethane extract of Nepeta sorgerae, the isolation and structure elucidation are now reported of a new isopimarane diterpenoid, named sorgerolone, and two known triterpenoids, oleanolic acid and ursolic acid. Antioxidant activity of the extracts and the isolated terpenoids was determined by the DPPH free radical scavenging and lipid peroxidation inhibition (beta-carotene bleaching) methods. Anticholinesterase activity of the extracts and isolates was investigated by Ellman's method against AChE and BChE enzymes. Although the antioxidant activity results were low, the AChE enzyme inhibition of the extracts and terpenoids was very promising. PMID:22816286

  11. Effects of Emic Waves on the Outer Electron Radiation Belt.

    NASA Astrophysics Data System (ADS)

    Horne, R. B.; Kersten, T.; Glauert, S.; Meredith, N. P.; Fraser, B. J.; Grew, R. S.

    2014-12-01

    Over the last few years there has been substantial progress to incorporate wave-particle interactions into global simulation models of the radiation belts. Models of plasmaspheric hiss and whistler mode chorus make a huge impact on the variability of the relativistic electron flux. Electromagnetic Ion Cyclotron (EMIC) waves also cause electron loss from the radiation belts but their effectiveness has not been fully quantified. Here we present the results of simulations using a new chorus diffusion matrix and demonstrate that in principle the outer electron radiation belt can be formed by wave acceleration from a soft electron spectrum. We also describe a new model for EMIC waves. Wave data derived from the fluxgate magnetometer on CRRES was used to define the power spectrum as a function of geomagnetic activity, L* and magnetic local time for Hydrogen and Helium band waves. We show that wave power depends on activity as measured by AE and Kp. Using an assumed ion composition, and previously defined plasma density models the PADIE code was used to calculate bounce and drift averaged diffusion rates for EMIC waves and incorporated into the BAS Radiation Belt Model together with whistler mode chorus, plasmaspheric hiss and radial diffusion. Thus the model can be driven by a time sequence of Kp with appropriate boundary conditions. By simulating a 100 day period in 1990 we show that the model can produce electron flux up to energies of several MeV. When EMIC waves are included they cause a significant reduction in the electron flux for energies greater than 2 MeV but only for pitch angles lower than about 60 degrees. The simulations show that the distribution of electrons left behind in space looks like a pancake distribution at MeV energies. We show that EMIC waves cannot remove electrons at all pitch angles even at 30 MeV and are therefore unlikely to set an upper energy limit to the outer radiation belt.

  12. Shaping mobile belts by small-scale convection.

    PubMed

    Faccenna, Claudio; Becker, Thorsten W

    2010-06-01

    Mobile belts are long-lived deformation zones composed of an ensemble of crustal fragments, distributed over hundreds of kilometres inside continental convergent margins. The Mediterranean represents a remarkable example of this tectonic setting: the region hosts a diffuse boundary between the Nubia and Eurasia plates comprised of a mosaic of microplates that move and deform independently from the overall plate convergence. Surface expressions of Mediterranean tectonics include deep, subsiding backarc basins, intraplate plateaux and uplifting orogenic belts. Although the kinematics of the area are now fairly well defined, the dynamical origins of many of these active features are controversial and usually attributed to crustal and lithospheric interactions. However, the effects of mantle convection, well established for continental interiors, should be particularly relevant in a mobile belt, and modelling may constrain important parameters such as slab coherence and lithospheric strength. Here we compute global mantle flow on the basis of recent, high-resolution seismic tomography to investigate the role of buoyancy-driven and plate-motion-induced mantle circulation for the Mediterranean. We show that mantle flow provides an explanation for much of the observed dynamic topography and microplate motion in the region. More generally, vigorous small-scale convection in the uppermost mantle may also underpin other complex mobile belts such as the North American Cordillera or the Himalayan-Tibetan collision zone. PMID:20520711

  13. Beyond the Kuiper Belt Edge

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott

    2012-01-01

    Of the thousands of known objects beyond Neptune, only one has a perihelion significantly beyond 50 AU, Sedna at 75 AU. Most Kuiper Belt surveys to date either did not go faint enough, did not have the required long cadence to detect very slow moving objects or covered too small of an area of sky to efficiently detect objects beyond 50 AU. The dynamical and physical properties of objects in this region offer key constraints on the formation and evolution of our solar system. In order to probe the Sedna like population of objects with moderate radii (100 km) we are conducting a deep wide-field outer solar system survey. This survey will allow us to determine if the objects beyond 50 AU are fainter than expected, if there is truly a dearth of objects, or if the Kuiper Belt continues again after some sizable gap possibly caused by a planet sized object. We will be able to examine the origin of Sedna and determine if it is unique (as once believed for Pluto) or one of a new class of object. We request one night in 2012B to recover interesting objects that will be discovered at Subaru in July 2012 and complete the sky coverage needed to constrain the Sedna-like population.

  14. Beyond the Kuiper Belt Edge

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott

    2013-01-01

    Of the thousands of known objects beyond Neptune, only one has a perihelion significantly beyond 50 AU, Sedna at 75 AU. Most Kuiper Belt surveys to date either did not go faint enough, did not have the required long cadence to detect very slow moving objects or covered too small of an area of sky to efficiently detect objects beyond 50 AU. The dynamical and physical properties of objects in this region offer key constraints on the formation and evolution of our solar system. In order to probe the Sedna like population of objects with moderate radii (100 km) we are conducting a deep wide-field outer solar system survey. This survey will allow us to determine if the objects beyond 50 AU are fainter than expected, if there is truly a dearth of objects, or if the Kuiper Belt continues again after some sizable gap possibly caused by a planet sized object. We will be able to examine the origin of Sedna and determine if it is unique (as once believed for Pluto) or one of a new class of object. We request one night in 2013B to recover a very interesting object that we discovered at Subaru in July 2012 and complete the sky coverage needed to constrain the Sedna-like population. This one night was awarded to us in 2012B but lost because of instrument problems.

  15. Jupiter's radiation belts and atmosphere

    NASA Technical Reports Server (NTRS)

    De Pater, I.; Dames, H. A. C.

    1979-01-01

    Maps and stripscans of the radio emission from Jupiter were made during the Pioneer 10 flyby in December 1973 at wavelengths of 6 cm, 21 cm, and 50 cm using the Westerbork telescope in the Netherlands. With this instrument the disk of the planet was resolved at 6 and 21 cm. The pictures are averaged over 15 deg of Jovian longitude. At 21 cm the stripscans clearly show the existence of a 'hot region' in the radiation belts at a System III longitude (1965.0) of 255 + or - 10 deg. Its flux is about 9% of the total nonthermal flux, and it has a volume emissivity enhanced by a factor of about 1.6 with respect to the general radiation belts. The temperature of the thermal disk at 21 cm appears to be 290 + or - 20 K. This is likely due to a high ammonia mixing ratio in the atmosphere, a factor of 4-5 larger than the expected solar value of 0.00015.

  16. 47. INTERIOR VIEW, DETAIL OF CONVEYOR BELT SYSTEM SYSTEM WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. INTERIOR VIEW, DETAIL OF CONVEYOR BELT SYSTEM SYSTEM WITH BACK BELT DROPPING HARDENED NAILS ON THE FRONT BELT TO BE TEMPERED; MOTION STOPPED - LaBelle Iron Works, Thirtieth & Wood Streets, Wheeling, Ohio County, WV

  17. The Foundations of Radiation Belt Research

    NASA Astrophysics Data System (ADS)

    Ludwig, G. H.

    2008-12-01

    phenomenon. It also provided the first hint that there were two distinct radiation belts, although that conclusion was not reached until later. Although that new information was quickly announced, the results of the high altitude nuclear detonations were kept secret until well into 1959. They clearly revealed the charged particle shells created by the Argos nuclear detonations. The next major step in mapping and understanding the high-intensity radiation involved the launch of deep space probes Pioneers III and IV in December 1958 and March 1959. Although both launches fell short in their primary objective, to reach the moon, they traveled far enough from the Earth to fully meet the needs of the scientific experiment. They very clearly showed the two-radiation belt structure, and mapped its extent. They also showed the probable effect of a magnetic storm on 25 February, thus indicating the direct influence of solar activity on the outer belt. By the end of 1959, the existence of the Van Allen Radiation Belts and their general structure were solidly established, early information about the composition of the radiation was appearing in print, and energetic work was under way to understand the physics of the processes involved.

  18. Any Way You Cut It! Molehills Out of Mountains. A Resource and Activity Guide for the Developmentally Disabled.

    ERIC Educational Resources Information Center

    Barringer, M. D.; Kosal-Smither, C.

    A resource and activity guide for the developmentally disabled that focuses on fine motor skills is presented. Attention is directed to fine motor behavior during the first year (vision, grasp, and release and reaching), and behaviors developing at 13 months (the interaction of fine motor and cognitive skills). An introductory section considers…

  19. Quaternary estimates of average slip-rates for active faults in the Mongolian Altay Mountains: the advantages and assumptions of multiple dating techniques

    NASA Astrophysics Data System (ADS)

    Gregory, L. C.; Walker, R. T.; Thomas, A. L.; Amgaa, T.; Bayasgalan, G.; Amgalan, B.; West, A.

    2010-12-01

    Active faults in the Altay Mountains, western Mongolia, produce surface expressions that are generally well-preserved due to the arid central-Asian climate. Motion along the right-lateral strike-slip and oblique-reverse faults has displaced major river systems by kilometres over millions of years and there are clear scarps and linear features in the landscape along the surface traces of active fault strands. With combined remote sensing and field work, we have identified sites with surface features that have been displaced by tens of metres as a result of cumulative motion along faults. In an effort to accurately quantify an average slip-rate for the faults, we used multiple dating techniques to provide an age constraint for the displaced landscapes. At one site on the Olgiy fault, we applied 10Be terrestrial cosmogenic nuclides (TCN) and uranium-series geochronology on boulder tops and in-situ formed carbonate rinds, respectively. Based on a displacement of approximately 17m, and geochronology results that range from 20-60ky, we resolve a slip-rate of less than 1 mm/yr. We have also applied optically stimulated luminescence (OSL), 10Be TCN, and U-series methods on the Ar Hotol fault. Each of these dating techniques provides unique constraints on the relationship between the ‘age’ of a displaced surface and the actual amount of displacement, and each has inherent assumptions. We will consider the advantages and assumptions made in utilising these techniques in western Mongolia- e.g. U-series dating of carbonate rinds can provide a minimum age for alluvial fan deposition, and inheritance must be considered when using TCN techniques on boulder tops. This will be put into the context of estimating accurate and geologically relevant slip-rates, and improving our understanding of the active deformation of the Mongolian Altay.

  20. [Effects of simulated nitrogen deposition on soil acid phosphomonoesterase activity and soil available phosphorus content in subtropical forests in Dinghushan Mountain].

    PubMed

    Li, Yin; Zeng, Shu-cai; Huang, Wen-juan

    2011-03-01

    An in situ field experiment was conducted to study the effects of simulated nitrogen (N) deposition on soil acid phosphomonoesterase activity (APA) and soil available phosphorous (AP) content in Pinus massoniana forest (PF), coniferous and broad-leaved mixed forest (MF), and monsoon evergreen broad-leaved forest (MEBF) in Dinghushan Mountain. In PF and MF, three treatments were installed, i.e., CK (0 kg N x hm(-2) x a(-1)), low N (50 kg N x hm(-2) x a(-1)), and medium N (100 kg N x hm(-2) x a(-1)); in MEBF, four treatments were installed, i.e., CK, low N, medium N, and high N (150 kg N x hm(-2) x a(-1)). The soil APA and soil AP content decreased with soil depth. The soil APA was the highest in MEBF, while the AP content had no significant difference in the three forests. The effects of N addition on soil APA differed with forest types. In MEBF, the APA was the highest (19.52 micromol x g(-1) x h(-1)) in low N treatment; while in PF and MF, the APA was the highest (12.74 and 11.02 micromol x g(-1) x h(-1), respectively) in medium N treatment. In the three forests, soil AP content was the highest in low N treatment, but had no significant differences among the N treatments. There was a significant positive correlation between soil APA and soil AP content. PMID:21657017

  1. Understanding Quaternions and the Dirac Belt Trick

    ERIC Educational Resources Information Center

    Staley, Mark

    2010-01-01

    The Dirac belt trick is often employed in physics classrooms to show that a 2n rotation is not topologically equivalent to the absence of rotation whereas a 4n rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors…

  2. 14 CFR 27.1413 - Safety belts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety...

  3. 14 CFR 27.1413 - Safety belts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety...

  4. 14 CFR 27.1413 - Safety belts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety...

  5. 14 CFR 27.1413 - Safety belts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety...

  6. 14 CFR 27.1413 - Safety belts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety...

  7. The Administrator's "Handy Dandy" Tool Belt

    ERIC Educational Resources Information Center

    Anderson, Terry

    2012-01-01

    Every good leader needs a tool belt. Throughout the author's years of building early childhood programs, she has acquired a number of tools for her personal belt. These tools have helped her sharpen her skills in supporting teachers and staff, connecting with families, and educating children. This article focuses on those leadership skills that…

  8. Situational characteristics of safety belt use.

    PubMed

    Fockler, S K; Cooper, P J

    1990-04-01

    Past research concerning the use and nonuse of safety belts has tended to stereotype users and nonusers as distinct entities on the basis of a single observed situation. The thought processes underlying the reasons given by drivers for using or not using seat belts have not been explored. The purpose of this study was to observe belt use by a group of drivers and describe factors contributing to their use or nonuse as defined by the drivers themselves. In-depth interviews were undertaken with 239 drivers whose safety belt wearing behavior was observed in specific city or highway driving locations. Vehicle license numbers, gender, and age group of selected drivers were used to retrieve driver records and insurance policy data. Open-ended questions were asked concerning their reasons for use or nonuse and their attitudes towards safety belts and other types of traffic safety countermeasures. Driver attitudes, characteristics, and records were compared between observed safety belt user and nonuser groups to validate variables predicting use or nonuse. Respondents' descriptions of the social and personal context of their choice to use or not use safety belts provide a broader view of seat belt wearing that suggests implications for planning future enforcement and education programs. PMID:2331287

  9. 14 CFR 31.63 - Safety belts.

    Code of Federal Regulations, 2010 CFR

    2010