Sample records for 3-d fault geometry

  1. Imaging the 3D geometry of pseudotachylyte-bearing faults

    NASA Astrophysics Data System (ADS)

    Resor, Phil; Shervais, Katherine

    2013-04-01

    Dynamic friction experiments in granitoid or gabbroic rocks that achieve earthquake slip velocities reveal significant weakening by melt-lubrication of the sliding surfaces. Extrapolation of these experimental results to seismic source depths (> 7 km) suggests that the slip weakening distance (Dw) over which this transition occurs is < 10 cm. The physics of this lubrication in the presence of a fluid (melt) is controlled by surface micro-topography. In order to characterize fault surface microroughness and its evolution during dynamic slip events on natural faults, we have undertaken an analysis of three-dimensional (3D) fault surface microtopography and its causes on a suite of pseudotachylyte-bearing fault strands from the Gole Larghe fault zone, Italy. The solidification of frictional melt soon after seismic slip ceases "freezes in" earthquake source geometries, however it also precludes the development of extensive fault surface exposures that have enabled direct studies of fault surface roughness. We have overcome this difficulty by imaging the intact 3D geometry of the fault using high-resolution X-ray computed tomography (CT). We collected a suite of 2-3.5 cm diameter cores (2-8 cm long) from individual faults within the Gole Larghe fault zone with a range of orientations (+/- 45 degrees from average strike) and slip magnitudes (0-1 m). Samples were scanned at the University of Texas High Resolution X-ray CT Facility, using an Xradia MicroCT scanner with a 70 kV X-ray source. Individual voxels (3D pixels) are ~36 ?m across. Fault geometry is thus imaged over ~4 orders of magnitude from the micron scale up to ~Dw. Pseudotachylyte-bearing fault zones are imaged as tabular bodies of intermediate X-ray attenuation crosscutting high attenuation biotite and low attenuation quartz and feldspar of the surrounding tonalite. We extract the fault surfaces (contact between the pseudotachylyte bearing fault zone and the wall rock) using integrated manual mapping, automated edge detection, and statistical evaluation. This approach results in a digital elevation model for each side of the fault zone that we use to quantify melt thickness and volume as well as surface microroughness and explore the relationship between these properties and the geometry, slip magnitude, and wall rock mineralogy of the fault.

  2. Geometry in 3-D

    NSDL National Science Digital Library

    Terese Herrera

    This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards. The online resources featured in Geometry in 3-D actively engage students in exploring a variety of geometric shapes, at times through lessons that involve building models or creating paper nets that fold into three-dimensional shapes; at other times, through technology that allows students to rotate and zoom in on figures, noting their attributes and complexity. Other lessons offer problems on surface area and volume, a part of every middle school curriculum. The problems, each with a different twist on the subject, challenge students to reconsider their understanding of how to measure solids. Activities for developing spatial sense, another primary objective in teaching geometry, are also featured. Finally, there are online galleries of geometric solids, included for the rare opportunity they offer to show your students the beauty in mathematics. In Background Information, you will find workshop sessions developed for teachers and other materials that may interest you as a professional. Each resource deals specifically with three-dimensional geometry topics that align with the geometry and measurement standards recommended by NCTM.

  3. Geometry and kinematics of the Arlar strike-slip fault, SW Qaidam basin, China: New insights from 3-D seismic data

    NASA Astrophysics Data System (ADS)

    Cheng, Xiang; Fu, Suotang; Wang, Haifeng; Yu, Xiangjiang; Cheng, Feng; Liu, Runchao; Du, Wei; Guo, Zhaojie

    2015-02-01

    The right-stepping en-échelon Kunbei fault system, consisting of the Hongliuquan, Arlar, XIII, and Kunbei faults, features importantly in the tectonic evolution of the southwest Qaidam basin. The 3D seismic cross-section interpretation and key horizon similarity attribute analysis show that the NWW-striking Arlar fault is composed of two steeply dipping faults (F1 and F2) in cross-sectional view, and branches eastward into two west-dipping faults (F5 and F6) in map view. The fact that the strata above T2 (the base of the early Miocene Xiayoushashan Formation) become dramatically thinner toward the high points of the Arlar fault suggests an early Miocene initiation (ca. 22.0 Ma) for this fault. As indicated by the windowed amplitude-related attribute maps, the Arlar fault and F5 (one branch of the Arlar fault) have cumulative sinistral offsets of ?8.6-8.7 km and ?5.2-5.4 km, respectively. These considerably greater strike-slip components, in conjunction with the respective maximum true dip-slip displacements of <2.2 km and <1.5 km, convincingly demonstrate that the Arlar fault and F5 are two predominantly left-lateral strike-slip faults. The other faults in the Kunbei fault system are similarly of strike-slip types. This means that the southern boundary of the Qaidam basin is not governed by south- or north-directed thrusting but rather strike-slip faulting, implying that the Qaidam basin is not a foreland basin of the Eastern Kunlun Range. Taking the Altyn Tagh fault into account, the Qaidam basin is essentially a strike-slip superimposed basin developing between two large left-lateral strike-slip faults.

  4. Early stage evolution of growth faults: 3D seismic insights from the Levant Basin, Eastern Mediterranean

    E-print Network

    Demouchy, Sylvie

    Early stage evolution of growth faults: 3D seismic insights from the Levant Basin, Eastern March 2008 Keywords: Growth fault Blind propagation Throw distribution Fault nucleation Segmentation a b s t r a c t The geometry and kinematic evolution of small growth faults were analysed from a high

  5. Personal authentication using 3-D finger geometry

    Microsoft Academic Search

    Sotiris Malassiotis; Niki Aifanti; Michael G. Strintzis

    2006-01-01

    In this paper a biometric authentication system based on measurements of the user's 3D hand geometry is proposed. The system relies on a novel real-time and low-cost 3D sensor that generates a dense range image of the scene. By exploiting 3D information we are able to limit the constraints usually posed on the environment and the placement of the hand,

  6. Three-dimensional Geometry of Magma Chamber Roof and Faults from 3D Seismic Reflection Data at the Lucky Strike Volcano, Mid-Atlantic Ridge

    Microsoft Academic Search

    V. Combier; T. Seher; S. C. Singh; W. Crawford; M. Cannat; J. Escartin; H. Carton

    2007-01-01

    A three-dimensional (3D) seismic reflection survey was carried out during the SISMOMAR 2005 experiment covering an area of 18x3.8 km2, which includes the Lucky Strike volcano and associated hydrothermal vent sites, part of the graben on top of the volcano, and extends out to the median valley bounding faults. The survey consisted of 39 lines shot at 100 m spacing

  7. 3D geometry of growth strata in a fault-propagation fold: insights into space-time evolution of the Crevillente Fault (Abanilla-Alicante sector), Betic Cordillera, Spain

    NASA Astrophysics Data System (ADS)

    Martin-Rojas, I.; Alfaro, P.; Estévez, A.

    2015-01-01

    This work presents a 3D geometric model of growth strata cropping out in a fault-propagation fold associated with the Crevillente Fault (Abanilla-Alicante sector) from the Bajo Segura Basin (eastern Betic Cordillera, southern Spain). The analysis of this 3D model enables us to unravel the along-strike and along-section variations of the growth strata, providing constraints to assess the fold development, and hence, the fault kinematic evolution in space and time. We postulate that the observed along-strike dip variations are related to lateral variation in fault displacement. Along-section variations of the progressive unconformity opening angles indicate greater fault slip in the upper Tortonian-Messinian time span; from the Messinian on, quantitative analysis of the unconformity indicate a constant or lower tectonic activity of the Crevillente Fault (Abanilla-Alicante sector); the minor abundance of striated pebbles in the Pliocene-Quaternary units could be interpreted as a decrease in the stress magnitude and consequently in the tectonic activity of the fault. At a regional scale, comparison of the growth successions cropping out in the northern and southern limits of the Bajo Segura Basin points to a southward migration of deformation in the basin. This means that the Bajo Segura Fault became active after the Crevillente Fault (Abanilla-Alicante sector), for which activity on the latter was probably decreasing according to our data. Consequently, we propose that the seismic hazard at the northern limit of the Bajo Segura Basin should be lower than at the southern limit.

  8. High resolution 3D laser scanner measurements of a strike-slip fault quantify its morphological anisotropy at all scales

    E-print Network

    1 High resolution 3D laser scanner measurements of a strike- slip fault quantify its morphological of a recently exhumed strike- slip fault has been measured by three independent 3D portable laser scanners different 3D field laser scanners and characterized its geometry in terms of scaling properties

  9. 3D seismic characterisation of an array of blind normal faults in the Levant Basin, Eastern Mediterranean

    E-print Network

    Demouchy, Sylvie

    3D seismic characterisation of an array of blind normal faults in the Levant Basin, Eastern The geometry, throw distribution and kinematics of an array of blind normal faults were investigated using allowing true blind faults to be distinguished from minor synsedimentary faults. A detailed analysis

  10. Automatic Fault Extraction (AFE) in 3D Seismic Data

    Microsoft Academic Search

    Geoffrey A. Dorn; Huw E. James

    Fault interpretation remains one of the most time-consuming aspects of 3D seismic interpretation. Faults are still most often manually picked as discontinuities in seismic amplitude. There have been several attempts to automate fault interpretation in the past that have failed to deliver acceptable interpretations with less effort in less time than manual methods. In general, these methods have required very

  11. 3D Geometry Projection from 2D to 3D

    E-print Network

    Jacobs, David

    n n n zzz yyy xxx P Points = y x tsss tsss S 3,22,21,2 3,12,11,1 Some matrix = n n vvv uuu I 21 21 of the points in P. #12;5 First, look at 2D rotation (easier) - n n yyy xxx 21 21 ... cossin sincos coordinates. That is, it's rotated. #12;6 Simple 3D Rotation - n n n zzz yyy xxx 21 21 21 ... 100 0cossin 0

  12. Coronary stent implantation changes 3-D vessel geometry and 3-D shear stress distribution

    Microsoft Academic Search

    Jolanda J. Wentzel; Deirdre M. Whelan; Willem J. van der Giessen; Heleen M. M. van Beusekom; Ivan Andhyiswara; Patrick W. Serruys; Cornelis J. Slager; Rob Krams

    2000-01-01

    Mechanisms of in-stent restenosis are not fully understood. Shear stress is known to play a role in plaque and thrombus formation and is sensitive to changes in regional vessel geometry. Hence, we evaluated the regional changes in 3-D geometry and shear stress induced by stent placement in coronary arteries of pigs.Methods. 3-D reconstruction was performed, applying a combined angiographic and

  13. The SCEC 3D Community Fault Model (CFM-v5): An updated and expanded fault set of oblique crustal deformation and complex fault interaction for southern California

    NASA Astrophysics Data System (ADS)

    Nicholson, C.; Plesch, A.; Sorlien, C. C.; Shaw, J. H.; Hauksson, E.

    2014-12-01

    Southern California represents an ideal natural laboratory to investigate oblique deformation in 3D owing to its comprehensive datasets, complex tectonic history, evolving components of oblique slip, and continued crustal rotations about horizontal and vertical axes. As the SCEC Community Fault Model (CFM) aims to accurately reflect this 3D deformation, we present the results of an extensive update to the model by using primarily detailed fault trace, seismic reflection, relocated hypocenter and focal mechanism nodal plane data to generate improved, more realistic digital 3D fault surfaces. The results document a wide variety of oblique strain accommodation, including various aspects of strain partitioning and fault-related folding, sets of both high-angle and low-angle faults that mutually interact, significant non-planar, multi-stranded faults with variable dip along strike and with depth, and active mid-crustal detachments. In places, closely-spaced fault strands or fault systems can remain surprisingly subparallel to seismogenic depths, while in other areas, major strike-slip to oblique-slip faults can merge, such as the S-dipping Arroyo Parida-Mission Ridge and Santa Ynez faults with the N-dipping North Channel-Pitas Point-Red Mountain fault system, or diverge with depth. Examples of the latter include the steep-to-west-dipping Laguna Salada-Indiviso faults with the steep-to-east-dipping Sierra Cucapah faults, and the steep southern San Andreas fault with the adjacent NE-dipping Mecca Hills-Hidden Springs fault system. In addition, overprinting by steep predominantly strike-slip faulting can segment which parts of intersecting inherited low-angle faults are reactivated, or result in mutual cross-cutting relationships. The updated CFM 3D fault surfaces thus help characterize a more complex pattern of fault interactions at depth between various fault sets and linked fault systems, and a more complex fault geometry than typically inferred or expected from projecting near-surface data down-dip, or modeled from surface strain and potential field data alone.

  14. Line Geometry for 3D Shape Understanding and Reconstruction

    E-print Network

    Pottmann, Helmut

    ,hofer,odehnal,wallner}@geometrie.tuwien.ac.at Abstract. We understand and reconstruct special surfaces from 3D data with line geometry methods. Based of locally intersecting surface normals. For the computational solution we use a modified version on estimated surface normals we use approximation techniques in line space to recognize and reconstruct

  15. 3D Simulations of Dynamic Rupture on Rough Faults

    NASA Astrophysics Data System (ADS)

    Shi, Z.; Day, S. M.

    2011-12-01

    Natural faults during their evolution stages manifest varying degrees of geometric complexities over a broad range of scales spanning from larger-scale features such as branching and segmentation to smaller-scale features such as topographic variations on the slip surface. At a microscopic scale, surface roughness affects the frictional properties through its role in the distribution and evolution of contact areas of the sliding surface. At a larger scale, the geometric irregularities of the fault affects the inter-seismic and post-seismic static stress distribution that is responsible for earthquake nucleation. Our study, however, focuses on the fundamental role that surface roughness plays in the dynamic processes of earthquake rupture propagation and resultant ground motion using numerical simulations of 3D dynamic rupture. As have been shown in several previous 2D numerical studies, dynamic ruptures propagating along rough fault surface can excite high-frequency radiation as they accelerate and decelerate from interaction with geometric irregularities. Also perturbation of local dynamic stress due to roughness contributes to the heterogeneous distributions of slip rate and slip over the entire fault. With the goal of producing more realistic physics-based dynamic ground motion, we perform 3D numerical simulations of dynamic rupture along faults with self-similar roughness distribution of wavelength scales spanning three orders of magnitude (10^2 -10^5 m). We examine the influence of fault roughness characteristics (shortest wavelength and amplitude-to-wavelength ratio) on the rupture behavior, the resultant ground motion pattern and the final slip pattern. The fault is governed by a rate-and-state friction with strongly velocity-weakening feature and the inelastic yielding of off-fault bulk material is subject to Drucker-Prager viscoplasticity. Initial investigations clearly indicate that the amount of high-frequency radiation generated and rupture properties are heavily influenced by the roughness properties. Detailed analyses of our simulation results will be presented at the conference.

  16. Color correction using 3D multi-view geometry

    NASA Astrophysics Data System (ADS)

    Shin, Dong-Won; Ho, Yo-Sung

    2015-01-01

    Recently, many 3D contents production tools using multi-view system has been introduced: e.g., depth estimation, 3D reconstruction and so forth. However, there is color mismatch problem in multiview system and it can cause big differences for the final result. In this paper we propose a color correction method using 3D multi-view geometry. The propose method finds correspondences between source and target viewpoint and calculates a translation matrix by using a polynomial regression technique. An experiment is performed in CIELab color space which is designed to approximate an human visual system and proposed method properly corrected the color compare to conventional methods. Moreover, we applied the proposed color correction method to 3D object reconstruction and we acquired a consistent 3D model in terms of color.

  17. 3-D GEOMETRY ENHANCEMENT BY CONTOUR OPTIMIZATION IN TURNTABLE SEQUENCES

    E-print Network

    Eisert, Peter

    , computer games, product presentations in e-commerce, or other virtual reality systems. Although the ren and design of 3-D models with high quality is still time consuming and thus expensive. This has motivated geometry. In order to circumvent the limitation of reconstructing the visual hull only, many extensions

  18. Nonlinear Probabilistic Estimation of 3D Geometry from Images

    E-print Network

    constraints involving non­Euclidean domains, such as those found in the 3­D vision geometry problems. Using are geometrically poorly leveraged by the image fea­ tures, involve nonlinear relationships, and have non­Euclidean state domains. To model such domains, a manifold­tangent framework is developed which allows non­Euclidean

  19. 3D Fault Network of the Murchison Domain, Yilgarn Craton

    NASA Astrophysics Data System (ADS)

    Murdie, Ruth; Gessner, Klaus

    2014-05-01

    The architecture of Archean granite-greenstone terranes is often controlled by networks of 10 km to 100 km-scale shear zones that record displacement under amphibolite facies to greenschist facies metamorphic conditions. The geometry of such crustal scale 'fault networks' has been shown to be highly relevant to understand the tectonic and metamorphic history of granite-greenstone terranes, as well as the availability of structural controlled fluid pathways related to magmatic and hydrothermal mineralization. The Neoarchean Yilgarn Craton and the Proterozoic orogens around its margins constitute one of Earth's greatest mineral treasure troves, including iron, gold, copper and nickel mineral deposits. Whereas the Yilgarn Craton is one of the best studied Archean cratons, its enormous size and limited outcrop are detrimental to the better understanding of what controls the distribution of these vast resources and what geodynamic processes were involved the tectonic assembly of this part of the Australian continent. Here we present a network of the major faults of the NW Yilgarn Craton between the Yalgar Fault, Murchison's NW contact with the Narryer Terrane to the Ida Fault, its boundary with the Eastern Goldfields Superterrane. The model has been constructed from various geophysical and geological data, including potential field grids, Geological Survey of Western Australia map sheets, seismic reflection surveys and magnetotelluric traverses. The northern extremity of the modelled area is bounded by the Proterozoic cover and the southern limit has been arbitrarily chosen to include various greenstone belts. In the west, the major faults in the upper crust, such as the Carbar and Chundaloo Shear Zones, dip steeply towards the west and then flatten off at depth. They form complex branching fault systems that bound the greenstone belts in a series of stacked faults. East of the Ida, the far east of the model, the faults have been integrated with Geoscience Australia's pmd*CRC Eastern Goldfields model. In the central portion, the major faults such as the Youanmi and Wattle Creek, dip to the east and can be followed into the fabric of the Yarraquin Seismic Province. The Wattle Creek Shear Zone in particular can be traced on all three of the Youanmi seismic lines. The greenstones are cradled between these major faults and antithetic westward dipping subsidiary faults such as the Edale Shear Zone. While the Ida Fault cannot be located with great confidence, the slight drop in Moho depth toward the east and the overall change of seismic texture delineate the Youanmi-Eastern Goldfields boundary. The Lawler's Anticline, presumably located in the hanging wall of the Ida Fault, again changes the style of faulting with the Lawler's tonalite forming the core of a 10 km-scale antiform. The fault network presented here is a milestone to a craton-wide integrated structural model and will hopefully contribute to provide a better spatial context for geological, geochemical and geophysical data in our quest to understand the tectonics and mineral potential of the Yilgarn craton.

  20. Detection and extraction of fault surfaces in 3D seismic data Israel Cohen1

    E-print Network

    Cohen, Israel

    that are unrelated to faults. Furthermore, creating a consistent geological interpretation from large 3D-seismicDetection and extraction of fault surfaces in 3D seismic data Israel Cohen1 , Nicholas Coult2 surfaces in 3D-seismic volumes. The seismic data are transformed into a volume of local

  1. Characterization of shallow normal fault systems in unconsolidated sediments using 3-D ground penetrating radar (SE Vienna Basin, Austria)

    NASA Astrophysics Data System (ADS)

    Spahic, D.; Exner, U.; Behm, M.; Grasemann, B.; Haring, A.

    2009-04-01

    In a gravel pit at the eastern margin of the Eisenstadt Basin, a subbasin of Vienna Basin (Austria), a set of normal faults crosscuts a Middle Miocene succession consisting of gravel layers, sandy gravels, fine-grained sands and silts with variable thicknesses between 1 and 4 m. These mainly friable sediments are cut by a numerous N-S striking high angle normal faults of ca. 0.5 - 10m length, offsetting, dragging and tilting the sedimentary layering. Normal faults occur either as isolated planes, or as parallel sets of high-angle faults dipping to the West. The outcrop is situated in the hanging wall of a major normal fault with a vertical displacement of at least 40m, which was interpreted as listric fault associated with a rollover anticline (Decker & Peresson, 1996). The displacement magnitude varies significantly along individual faults from cm to a few meters. The strong displacement gradients along these short faults result in the formation of perturbation fields around them, which deflect the initially planar sedimentary marker beds in the vicinity of the faults producing a pronounced reverse fault drag. None of these short faults display listric geometries or are associated with low angle detachment horizons. The spatial orientation and distribution of the faults and the associated fault drag was mapped in detail on a 3D laser scan of the outcrop wall. In order to assess the 3D distribution and geometry of this fault system, a series of parallel GPR (ground penetrating radar) profiles were recorded with a low frequency antenna behind the well-studied outcrop wall. The profile data were interpolated into a 3D GPR cube. Faults with normal offset of ca. 0.5-1,5 m can be mapped by detailed correlation of conspicuous marker horizons. Additionally, the deflection of markers around the fault planes can be documented from the GPR dataset. Both outcrop and GPR data were compiled in a 3D structural model using Gocad (Paradigm). The detailed geometry of the sedimentary horizons, the normal fault system and the associated fault drag is used to infer the subsurface continuation of the major normal fault below. Kinematic reconstruction of the fault plane using the Coulomb Collapse Theory predicts a bending of the fault plane into a subhorizontal orientation at ~70 m below the outcrop level. It is important to note, that these kind of reconstruction techniques inherently assume a listric fault geometry and therefore will always result in extensional fault, which flatten at a certain depth. However, correlation of reconstructed detachment this level with outcrop observation in the same gravel pit strongly question the interpretation as a listric fault. Instead, we suggest that in analogy to the smaller sized structures in the hanging wall, the observed deflection of stratigraphic horizons could be caused by displacement gradients along the fault, and that the deflection of markers should be interpreted as large scale fault drag instead of a rollover anticline. Decker, K. & Peresson, H. 1996. Rollover and hanging-wall collapse during Sarmatian/Pannonian synsedimentary extension in the Eisenstadt Basin. Mitt. Ges. Geol. Bergbaustud. Österr. 41, 45-52.

  2. Intensity of joints associated with an extensional fault zone: an estimation by poly3d .

    NASA Astrophysics Data System (ADS)

    Minelli, G.

    2003-04-01

    The presence and frequency of joints in sedimentary rocks strongly affects the mechanical and fluid flow properties of the host layers. Joints intensity is evaluated by spacing, S, the distance between neighbouring fractures, or by density, D = 1/S. Joint spacing in layered rocks is often linearly related to layer thickness T, with typical values of 0.5 T < S < 2.0 T . On the other hand, some field cases display very tight joints with S << T and nonlinear relations between spacing and thickness , most of these cases are related to joint system “genetically” related to a nearby fault zone. The present study by using the code Poly3D (Rock Fracture Project at Stanford), numerically explores the effect of the stress distribution in the neighbour of an extensional fault zone with respect to the mapped intensity of joints both in the hanging wall and in the foot wall of it (WILLEMSE, E. J. M., 1997; MARTEL, S. J, AND BOGER, W. A,; 1998). Poly3D is a C language computer program that calculates the displacements, strains and stresses induced in an elastic whole or half-space by planar, polygonal-shaped elements of displacement discontinuity (WILLEMSE, E. J. M., POLLARD, D. D., 2000) Dislocations of varying shapes may be combined to yield complex three-dimensional surfaces well-suited for modeling fractures, faults, and cavities in the earth's crust. The algebraic expressions for the elastic fields around a polygonal element are derived by superposing the solution for an angular dislocation in an elastic half-space. The field data have been collected in a quarry located close to Noci town (Puglia) by using the scan line methodology. In this quarry a platform limestone with a regular bedding with very few shale or marly intercalations displaced by a normal fault are exposed. The comparison between the mapped joints intensity and the calculated stress around the fault displays a good agreement. Nevertheless the intrinsic limitations (isotropic medium and elastic behaviour) of this project encourages other application of Poly3d. References WILLEMSE, E. J. M., 1997, Segmented normal faults: Correspondence between three-dimensional mechanical models and field data: Journal of Geophysical Research, v. 102, p. 675-692. MARTEL, S. J, AND BOGER, W. A, 1998, Geometry and mechanics of secondary fracturing around small three-dimensional faults in granitic rock: Journal of Geophysical Research, v. 103, p. 21,299-21,314. WILLEMSE, E. J. M., POLLARD, D. D., 2000, Normal fault growth: evolution of tipline shapes and slip distribution: in Lehner, F.K. &Urai, J.L. (eds.), Aspects of Tectonic Faulting, Springer -Verlag , Berlin, p. 193-226.

  3. 3D Dynamics of Oblique Rift Systems: Fault Evolution from Rift to Break-up

    NASA Astrophysics Data System (ADS)

    Brune, S.

    2014-12-01

    Rift evolution and passive margin formation has been thoroughly investigated using conceptual and numerical models in two dimensions. However, the 2D assumption that the extension direction is perpendicular to the rift trend is often invalid. In fact, the majority of rift systems that lead to continental break-up during the last 150 My involved moderate to high rift obliquity. Yet, the degree to which oblique lithospheric extension affects first-order rift and passive margin properties like surface stress pattern, fault azimuths, and basin geometry, is still not entirely clear. This contribution provides insight in crustal stress patterns and fault orientations by applying a 3D numerical rift model to oblique extensional settings. The presented forward experiments cover the whole spectrum of oblique extension (i.e. rift-orthogonal extension, low obliquity, high obliquity, strike-slip deformation) from initial deformation to breakup. They are conducted using an elasto-visco-plastic finite element model and involve crustal and mantle layers accounting for self-consistent necking of the lithosphere. Even though the model setup is very simple (horizontally layered, no inherited faults), its evolution exhibits a variety of fault orientations that are solely caused by the interaction of far-field stresses with rift-intrinsic buoyancy and strength. Depending on rift obliquity, these orientations involve rift-parallel, extension-orthogonal, and intermediate normal fault directions as well as strike-slip faults. Allowing new insights on fault patterns of the proximal and distal margins, the model shows that individual fault populations are activated in a characteristic multi-phase evolution driven by lateral density variations of the evolving rift system. Model results are in very good agreement with inferences from the well-studied Gulf of Aden and provide testable predictions for other rifts and passive margins worldwide.

  4. A linguistic geometry for 3D strategic planning

    NASA Technical Reports Server (NTRS)

    Stilman, Boris

    1995-01-01

    This paper is a new step in the development and application of the Linguistic Geometry. This formal theory is intended to discover the inner properties of human expert heuristics, which have been successful in a certain class of complex control systems, and apply them to different systems. In this paper we investigate heuristics extracted in the form of hierarchical networks of planning paths of autonomous agents. Employing Linguistic Geometry tools the dynamic hierarchy of networks is represented as a hierarchy of formal attribute languages. The main ideas of this methodology are shown in this paper on the new pilot example of the solution of the extremely complex 3D optimization problem of strategic planning for the space combat of autonomous vehicles. This example demonstrates deep and highly selective search in comparison with conventional search algorithms.

  5. Quantifying Natural Fault Geometry: Statistics of Splay Fault Angles by Ryosuke Ando,*

    E-print Network

    Shaw, Bruce E.

    Short Note Quantifying Natural Fault Geometry: Statistics of Splay Fault Angles by Ryosuke Ando,* Bruce E. Shaw, and Christopher H. Scholz Abstract We propose a new approach to quantifying fault system geometry, using an objective fit of the fault geometry to a test function, specifically here a fault branch

  6. High resolution 3D laser scanner measurements of a strike-slip fault

    Microsoft Academic Search

    D. Marsan; F. Renard; C. Voisin; J. Schmittbuhl

    2005-01-01

    The roughness on active fault planes is supposed to concentrate the stress along asperities and therefore control earthquakes nucleation. Unfortunately, the small scale roughness cannot be imaged for faults at depth because of the lack of resolution of earthquakes relocalization methods. The surface roughness of a recently exhumed strike-slip fault in the Alps has been measured by three independent 3D

  7. Stochastic simulations of fault networks in 3D structural Nicolas Cherpeau,a

    E-print Network

    Boyer, Edmond

    structures and even exhaustively sampled 3D seismic surveys cannot re- move interpretational uncertaintiesStochastic simulations of fault networks in 3D structural modeling Nicolas Cherpeau,a , Guillaume Nancy, France Abstract 3D Structural modeling is a major instrument in geosciences, e

  8. 3D stochastic geophysical inversion for contact surface geometry

    NASA Astrophysics Data System (ADS)

    Lelièvre, Peter; Farquharson, Colin; Bijani, Rodrigo

    2015-04-01

    Geologists' interpretations about the Earth typically involve distinct rock units with contacts (interfaces) between them. As such, 3D geological Earth models typically comprise wireframe contact surfaces of tessellated triangles or other polygonal planar facets. In contrast, standard minimum-structure geophysical inversions are performed on meshes of space-filling cells (typically prisms or tetrahedra) and recover smoothly varying physical property distributions that are inconsistent with typical geological interpretations. There are several approaches through which mesh-based geophysical inversion can help recover models with some of the desired characteristics. However, a more effective strategy is to consider a fundamentally different type of inversion that works directly with models that comprise surfaces representing contacts between rock units. We are researching such an approach, our goal being to perform geophysical forward and inverse modelling directly with 3D geological models of any complexity. Geological and geophysical models should be specified using the same parameterization such that they are, in essence, the same Earth model. We parameterize the wireframe contact surfaces in a 3D model as the coordinates of the nodes (facet vertices). The physical properties of each rock unit in a model remain fixed while the geophysical inversion controls the position of the contact surfaces via the control nodes, perturbing the surfaces as required to fit the geophysical data responses. This is essentially a "geometry inversion", which can be used to recover the unknown geometry of a target body or to investigate the viability of a proposed Earth model. We apply global optimization strategies to solve the inverse problem, including stochastic sampling to obtain statistical information regarding the likelihood of particular features in the model, helping to assess the viability of a proposed model. Jointly inverting multiple types of geophysical data is simple, requiring no additional mathematical coupling measure in the objective function. The use of global optimization methods introduces high computational costs: to provide computationally feasible inversion methods we reduce the dimensionality of the problem by allowing the inversion to control the nodes in a coarse representation of the wireframe model, which is refined before calculating the geophysical responses at each iteration. This strategy also provides a simple and effective way to regularize the inverse problem. We have tested our inversion method on several illustrative synthetics and applied it to a joint inversion of gravity and magnetic survey data collected above an IOCG deposit.

  9. Exploring fault geometry uncertainties in finite-slip inversion with multiple moment tensor inversion

    NASA Astrophysics Data System (ADS)

    Fan, W.; Shearer, P. M.; Masters, G.; Ji, C.

    2014-12-01

    Finite-fault source inversions are often performed with an assumed fault geometry. Green's functions calculated using a fixed strike, dip and rake can introduce hard-to-quantify errors in the inversions if the true fault geometry deviates from the model assumptions. For mega-earthquakes with large rupture areas, it is important to consider fault curvature and other non-planar fault effects. To accommodate uncertainties in the fault geometry, we propose to parameterize the fault as multiple moment-tensor sources within a 3D grid of possible source locations. The grid is defined with respect to an assumed initial fault plane, spanning the likely 2D rupture extent and a small range in the direction to normal to the fault to accommodate errors in assumed fault location or orientation. Instead of determining the slip-rate history, a moment-rate function is solved. There are six unknowns per point at a given frequency and the best-fitting double-couple (i.e., strike and dip) can be extracted from the results. If we assume the earthquake occurs within a few fault planes, the unknowns to be solved should be spatially sparse. Recently emerging tools such as compressive sensing (CS) can be used to deal with the problem. For a case study, we will analyze the 2013 Okhotsk Mw 8.3 earthquake and hope to understand the uncertainty limits caused by fault geometry in the finite fault modeling.

  10. Detection and extraction of fault surfaces in 3D seismic data

    Microsoft Academic Search

    Israel Cohen; Nicholas Coult; Anthony A. Vassiliou

    2006-01-01

    We propose an efficient method for detecting and extract- ing fault surfaces in 3D-seismic volumes. The seismic data aretransformedintoavolumeoflocal-fault-extractionLFE estimatesthatrepresentsthelikelihoodthatagivenpointlies onafaultsurface.Wepartitionthefaultsurfacesintorelative- lysmalllinearportions,whichareidentifiedbyanalyzingtilt- ed and rotated subvolumes throughout the region of interest. Directional filtering and thresholding further enhance the seismic discontinuities that are attributable to fault surfaces. Subsequently, the volume of LFE estimates is skeletonized, and individual fault surfaces are extracted

  11. New High-Resolution 3D Seismic Imagery of Deformation and Fault Architecture Along Newport-Inglewood/Rose Canyon Fault in the Inner California Borderlands

    NASA Astrophysics Data System (ADS)

    Holmes, J. J.; Bormann, J. M.; Driscoll, N. W.; Kent, G.; Harding, A. J.; Wesnousky, S. G.

    2014-12-01

    The tectonic deformation and geomorphology of the Inner California Borderlands (ICB) records the transition from a convergent plate margin to a predominantly dextral strike-slip system. Geodetic measurements of plate boundary deformation onshore indicate that approximately 15%, or 6-8 mm/yr, of the total Pacific-North American relative plate motion is accommodated by faults offshore. The largest near-shore fault system, the Newport-Inglewood/Rose Canyon (NI/RC) fault complex, has a Holocene slip rate estimate of 1.5-2.0 mm/yr, according to onshore trenching, and current models suggest the potential to produce an Mw 7.0+ earthquake. The fault zone extends approximately 120 km, initiating from the south near downtown San Diego and striking northwards with a constraining bend north of Mt. Soledad in La Jolla and continuing northwestward along the continental shelf, eventually stepping onshore at Newport Beach, California. In late 2013, we completed the first high-resolution 3D seismic survey (3.125 m bins) of the NI/RC fault offshore of San Onofre as part of the Southern California Regional Fault Mapping project. We present new constraints on fault geometry and segmentation of the fault system that may play a role in limiting the extent of future earthquake ruptures. In addition, slip rate estimates using piercing points such as offset channels will be explored. These new observations will allow us to investigate recent deformation and strain transfer along the NI/RC fault system.

  12. High resolution 3D laser scanner measurements of a strike-slip fault quantify its morphological anisotropy at all scales

    E-print Network

    High resolution 3D laser scanner measurements of a strike-slip fault quantify its morphological, and J. Schmittbuhl (2006), High resolution 3D laser scanner measurements of a strike-slip fault quantify] The surface roughness of a recently exhumed strike- slip fault plane has been measured by three independent 3D

  13. The 3D Geometry of Dark Matter Halos

    E-print Network

    J. -F. Becquaert; F. Combes

    1997-04-10

    The thickness of the neutral hydrogen layer, coupled with the rotation curve, traces the outer dark matter potential. We estimate the amplitude of the flaring in spiral galaxies from a 3D model of the HI gas. Warps in particular are explicitly parametrized in the form of an harmonical density wave. Applying our method to the galaxy NGC 891, the only model that could fit the observations, and in particular the HI at large height above the plane, includes a strong warp with a line of node almost coinciding with the line of sight. This high-Z HI is not observed at the most extreme velocity channels, those corresponding to high rotational velocities. This is accounted for by the model, since orbits in the tilted planes are not circular, but elongated, with their minor axis in the galaxy plane. Their velocity on the major axis (i.e. at their maximal height above the plane) is then 30% less than in the plane. We finally connect the modelled vertical outer gaseous distribution to the dark matter through hydrodynamical and gravitational equations. Under the assumption of isotropy of the gaseous velocity dispersion, we conclude on a very flattened halo geometry for the galaxy NGC 891 ($q \\approx 0.2$), while a vertical velocity dispersion smaller that the radial one would lead to a less flattened Dark Matter Halo ($q \\approx 0.4-0.5$). Both results however suggests that dark matter is dissipative or has been strongly influenced by the gas dynamics.

  14. Indoor Modelling Benchmark for 3D Geometry Extraction

    NASA Astrophysics Data System (ADS)

    Thomson, C.; Boehm, J.

    2014-06-01

    A combination of faster, cheaper and more accurate hardware, more sophisticated software, and greater industry acceptance have all laid the foundations for an increased desire for accurate 3D parametric models of buildings. Pointclouds are the data source of choice currently with static terrestrial laser scanning the predominant tool for large, dense volume measurement. The current importance of pointclouds as the primary source of real world representation is endorsed by CAD software vendor acquisitions of pointcloud engines in 2011. Both the capture and modelling of indoor environments require great effort in time by the operator (and therefore cost). Automation is seen as a way to aid this by reducing the workload of the user and some commercial packages have appeared that provide automation to some degree. In the data capture phase, advances in indoor mobile mapping systems are speeding up the process, albeit currently with a reduction in accuracy. As a result this paper presents freely accessible pointcloud datasets of two typical areas of a building each captured with two different capture methods and each with an accurate wholly manually created model. These datasets are provided as a benchmark for the research community to gauge the performance and improvements of various techniques for indoor geometry extraction. With this in mind, non-proprietary, interoperable formats are provided such as E57 for the scans and IFC for the reference model. The datasets can be found at: http://indoor-bench.github.io/indoor-bench.

  15. 3D microstructural and microchemical characteristics of SAFOD fault gouge: implications for understanding fault creep

    NASA Astrophysics Data System (ADS)

    Warr, Laurence; Wojatschke, Jasmaria; Carpenter, Brett; Marone, Chris; Schleicher, Anja; van der Pluijm, Ben

    2013-04-01

    Fault creep on the SAFOD section of the San Andreas Fault occurs along mechanically weak fault gouge characterized by high proportions of hydrous clay minerals, namely smectite, illite-smectite and chlorite-smectite phases. These minerals are concentrated along closely spaced, interconnected polished slip surfaces that give the gouge its characteristic scaly fabric. Although it is generally accepted that the creep behavior of the gouge relates to the concentration of these minerals, the precise mechanisms by which clay minerals weaken rock is currently a topic of debate. In this contribution we present the first results from a "slice-and-view" study of SAFOD gouge material by focused ion beam - scanning electron microscopy (Zeiss Auriga FIB/SEM), which allows the reconstruction of the microstructure and microchemistry of mineralized slip surfaces in 3D. The core and cuttings samples studied were selected from ca. 3297 m measured depth and represent some of the weakest materials yet recovered from the borehole, with a frictional coefficient of ca. 0.10 and a healing rate close to zero. This gouge contains abundant serpentine and smectite minerals, the latter of which was identified by X-ray diffraction to be saponite, after Mg- and glycol intercalation. Imaging and chemical analyses reveal nanometer scale thin alteration seams of saponite clay distributed throughout the ca. 50 micron thick sheared serpentinite layer that coats the slip surfaces. The base of this layer is defined by cataclastically deformed iron oxide minerals. The 3D fabric implies the orientation of the hydrated smectite minerals, which are interconnected and lie commonly sub parallel to the slip surface, are responsible for the gouge creep behavior in the laboratory. These minerals, and related interlayered varieties, are particularly weak due to their thin particle size and large quantities of adsorbed water, properties that are expected to persist down to mid-crustal depth (ca. 10 km). Creep of the San Andres Fault at Parkfield can therefore be adequately explained by the nature and abundance of smectite lattice layers that provide a nanometer-scale control on the mechanisms of fault behavior.

  16. Application of neural networks for identification of faults in a 3D seismic survey offshore Tunisia

    NASA Astrophysics Data System (ADS)

    Mastouri, Raja; Marchant, Robin; Marillier, François; Jaboyedoff, Michel; Bouaziz, Samir

    2013-04-01

    The Kerkennah High area (offshore Tunisia) is dominated by series of horst and grabens resulting from multiple tectonic events and multiphase stress (extension, compression, translation). In order to decipher this complex structural history from a 3D seismic survey, a neural network is applied to extract a fault-cube from the amplitude data (which does not image faults directly). The neural network transforms seismic attributes into a new 3D data cube in which faults are highlighted. This technique comprises the following steps. First, we compute several seismic attributes (dip-steering similarity, curvature, frequency, ridge and fault enhancement filters…) that enhance different aspects of the seismic data related to faulting. In a second step, a number of points in the seismic data are selected as representative of either faults or areas devoid of faults. These points are tested by the artificial neural network to determine the range in which the different attributes are representative of faults or not. Based on this learning phase, the neural network is then applied to the entire 3D seismic cube to produce a fault-cube that contains only faults which contrast and continuity have been enhance.

  17. SIMULATION OF GEOMETRY AND SHADOW EFFECTS IN 3D ORGANIC POLYMER SOLAR CELLS

    E-print Network

    Kassegne, Samuel Kinde

    SIMULATION OF GEOMETRY AND SHADOW EFFECTS IN 3D ORGANIC POLYMER SOLAR CELLS OF THE THESIS Simulation of Geometry and Shadow Effects in 3D Organic Polymer Solar Cells by Mihir Prakashbhai solar energy closer to grid price parity. Major studies have been made in improving solar cell

  18. Using 3D Computer Graphics Multimedia to Motivate Teachers' Learning of Geometry and Pedagogy

    E-print Network

    Spagnolo, Filippo

    Using 3D Computer Graphics Multimedia to Motivate Teachers' Learning of Geometry and Pedagogy Tracy This paper describes the implementation of 3D computer graphics multimedia, developed with an institutional technology grant, in a geometry methods course for elementary teachers. Computer graphics demonstrations

  19. Geometry videos : a new representation for 3D animations

    E-print Network

    Briceño Pulido, Héctor Manuel, 1974-

    2003-01-01

    Animations of three-dimensional computer graphics are becoming an increasingly prevalent medium for communication. There are many sources of 3D animations including physical simulations, scientific visualizations, and ...

  20. Improved Scanning Geometry to Collect 3D-Geometry Data in Flat Samples

    SciTech Connect

    Krueger, P.; Niese, S.; Zschech, E. [Fraunhofer IZFP-D, Maria-Reiche-Str. 2, 01109 Dresden (Germany); Gelb, J.; Feser, M. [Xradia Inc., 5052 Commercial Circle, Concord, CA 94520 (United States)

    2011-09-09

    3D integration through silicon technology of integrated circuits challenges non-destructive testing methods. 3D x-ray methods are the techniques of choice to localize defects in interconnects. The development of high-power x-ray sources enabled the use of x-ray microscopy in laboratory tools. Those devices are able to resolve features down to 40 nm in an acceptable measurement time. However, the field of view is very limited to 16 {mu}m in high-resolution mode and to 65 {mu}m in large-field-of-view mode. To record tomography data, the size of the samples must not exceed the field of view to circumvent specific artifacts. Semiconductor samples usually do not fulfill the condition mentioned above since they have the shape of flat sheets. Therefore limited-angle tomography is typically used. The missing angles cause typical capping artifacts and poor signal-to-noise ratio. We present a modified scanning geometry that overcomes some of the artifacts and yields a better image quality. The geometry and potential applications are presented in comparison to the traditional limited-angle tomography.

  1. Using 3D Computer Graphics Multimedia to Motivate Preservice Teachers' Learning of Geometry and Pedagogy

    ERIC Educational Resources Information Center

    Goodson-Espy, Tracy; Lynch-Davis, Kathleen; Schram, Pamela; Quickenton, Art

    2010-01-01

    This paper describes the genesis and purpose of our geometry methods course, focusing on a geometry-teaching technology we created using NVIDIA[R] Chameleon demonstration. This article presents examples from a sequence of lessons centered about a 3D computer graphics demonstration of the chameleon and its geometry. In addition, we present data…

  2. Defining 3D seismogenic faults to improve the probabilistic seismic hazard model: a case study from central Apennines (Italy)

    NASA Astrophysics Data System (ADS)

    Boncio, P.; Pace, B.; Lavecchia, G.

    2003-04-01

    Italy has a long history of large and moderate earthquakes. Contrary to other areas in the world, the deformation velocity across the Apennines is relatively low, large earthquakes may have long recurrence intervals (>=1000 a) and historical records may be not representative of the whole seismic activity. Several case studies clearly showed that earthquakes occur on existing faults having structural, geomorphic and paleoseismic features which can be recognised and quantified by geologic investigations. This strongly suggests that faults may greatly improve Seismic Hazard Assessment (SHA). Geology-based time-dependent SHA methods have been developing, also in Italy. These new methods require information on the geometric, kinematic and energetic parameters of the major seismogenic faults. Using surface data alone (faults by geological mapping i.e. 2D linear features) may create some problems in SHA. Linear faults are far from represent both the real radiating-energy sources and the likely epicentres of the attended earthquakes. It is well known that seismic moment is strictly dependent on the fault area. It follows that fault area should be the geological parameters to be used for SHA. Therefore, the third dimension is essential. In this work we define a model of seismogenic sources, suitable for SHA purposes, for the central Apennines of Italy. Our approach is mainly structural-seismotectonic. We integrate surface geology data with seismological and subsurface structural data (3D approach). A fundamental step is the definition of the seismogenic layer thickness. We used well located background seismicity as well as the depth distribution of aftershock zones. We also compared the instrumental seismicity with the strength and behaviour (frictional vs. plastic) of the crust by rheological profiling. In most cases the hypocentral distributions and the reological profiles are in good agreement, suggesting that rheological profiling may be a powerful tool in estimating the brittle layer thickness where detailed seismological data are lacking. Once the 3D fault features and a segmentation model have been defined, the step onward is the computation of the maximum magnitude and the mean recurrence time of the attended earthquake (essential for SHA). We compared three energetic parameters estimates: historical (fault-historical earthquakes association), geometrical (from fault geometry and kinematics) and geometrical revised (geometrical approach corrected, when necessary, by earthquake scaling laws).

  3. Deterministic Generation of High-Frequency Ground Motion with 3-D Simulations of Dynamic Ruptures along Rough Faults

    NASA Astrophysics Data System (ADS)

    Shi, Z.; Day, S. M.

    2013-12-01

    We generate high-frequency ground motion deterministically by performing 3-D simulations of dynamic ruptures on rough faults. Our rupture model employs self-similar rough-fault geometry, strongly rate-weakening friction and inelastic off-fault yielding. Using sufficiently small mesh size and a wide range of roughness wavelength in our simulations, we resolve wavefield spectral components up to greater than 10 Hz, permitting comparisons with empirical ground-motion intensity measures over much of the frequency range of engineering interest. The simulated ground accelerations have near-flat power spectra from a few tenths of a Hz to source-dependent upper frequency of slightly less than 10 Hz. Our initial studies with a halfspace medium and homogeneous (depth-dependent) stress produced site-averaged synthetic response spectra having characteristics, including the distance and period dependence of the median values, absolute level and intra-event standard deviation, comparable to appropriate empirical estimates, throughout the period range 0.1-3.0 sec. With the goal of elucidating generic aspects of ground motion that are still not well defined by existing data, we extend the preliminary validation study by using more realistic velocity models, multiple realizations of fault roughness, and a range of target event sizes. In addition, we examine the influence of post-seismic heterogeneous stress loading left behind by each rough-fault event on the dynamics of the successive rupture, which may provide useful insights into the mechanics of natural earthquake cycles.

  4. Combining recognition and geometry for data-driven 3D reconstruction

    E-print Network

    Owens, Andrew (Andrew Hale)

    2013-01-01

    Today's multi-view 3D reconstruction techniques rely almost exclusively on depth cues that come from multiple view geometry. While these cues can be used to produce highly accurate reconstructions, the resulting point ...

  5. Construct3D: A Virtual Reality Application for Mathematics and Geometry Education

    Microsoft Academic Search

    Hannes Kaufmann; Dieter Schmalstieg; Michael Wagner

    2000-01-01

    Construct3D is a three dimensional geometric construction tool based on the collaborative augmented reality system 'Studierstube'. Our setup uses a stereoscopic head mounted display (HMD) and the Personal Interaction Panel (PIP) - a two-handed 3D interaction tool that simplifies 3D model interaction. Means of application in mathematics and geometry education at high school as well as university level are being

  6. Computing Geometry-aware Handle and Tunnel Loops in 3D Models Tamal K. Dey

    E-print Network

    Xuan, Dong

    detection of loops on surfaces that are associated with features such as `handles' and `tunnels'. A 3D modelComputing Geometry-aware Handle and Tunnel Loops in 3D Models Tamal K. Dey Ohio State University recognition benefit from computing loops on surfaces that wrap around their `handles' and `tunnels'. Computing

  7. Geometry and growth of sill complexes: insights using 3D seismic from the North Rockall Trough

    Microsoft Academic Search

    K. Thomson; D. Hutton

    2004-01-01

    Doleritic sill complexes, which are an important component of volcanic continental margins, can be imaged using 3D seismic reflection data. This allows unprecedented access to the complete 3D geometry of the bodies and an opportunity to test classic sill emplacement models. The doleritic sills associated with basaltic volcanism in the North Rockall Trough occur in two forms. Radially symmetrical sill

  8. Multiview Geometry for Texture Mapping 2D Images Onto 3D Range Data Lingyun Liu and Ioannis Stamos

    E-print Network

    Wolberg, George

    technology with traditional digital photography. A system- atic way for registering 3D range scans and 2DMultiview Geometry for Texture Mapping 2D Images Onto 3D Range Data £ Lingyun Liu and Ioannis 3D registration techniques for texture mapping 2D images onto 3D range data. The 3D range scans

  9. Listric versus planar normal fault geometry: an example from the Eisenstadt-Sopron Basin (E Austria)

    NASA Astrophysics Data System (ADS)

    Spahi?, Darko; Exner, Ulrike; Behm, Michael; Grasemann, Bernhard; Haring, Alexander; Pretsch, Herbert

    2011-10-01

    In a gravel pit at the eastern margin of the Eisenstadt-Sopron Basin, a satellite of Vienna Basin (Austria), Neogene sediments are exposed in the hanging wall of a major normal fault. The anticlinal structure and associated conjugated secondary normal faults were previously interpreted as a rollover anticline above a listric normal fault. The spatial orientation and distribution of sedimentary horizons and crosscutting faults were mapped in detail on a laser scan of the outcrop wall. Subsequently, in order to assess the 3D distribution and geometry of this fault system, a series of parallel ground penetrating radar (GPR) profiles were recorded behind the outcrop wall. Both outcrop and GPR data were compiled in a 3D structural model, providing the basis for a kinematic reconstruction of the fault plane using balanced cross-section techniques. However, the kinematic reconstruction results in a geologically meaningless normal fault cutting down- and up-section. Additionally, no evidence for a weak layer serving as ductile detachment horizon (i.e. salt or clay horizon) can be identified in stratigraphic profiles. Instead, the observed deflection of stratigraphic horizons may be caused by a displacement gradient along a planar master fault, with a maximum displacement in the fault centre, decreasing towards the fault tips. Accordingly, the observed deflection of markers in the hanging wall—and in a nearby location in the footwall of the normal fault—is interpreted as large-scale fault drag along a planar fault that records a displacement gradient, instead of a rollover anticline related to a listric fault.

  10. Complex patterns of faulting revealed by 3D seismic data at the West Galicia rifted margin

    NASA Astrophysics Data System (ADS)

    Reston, Timothy; Cresswell, Derren; Sawyer, Dale; Ranero, Cesar; Shillington, Donna; Morgan, Julia; Lymer, Gael

    2015-04-01

    The west Galicia margin is characterised by crust thinning to less than 3 km, well-defined fault blocks, which overlie a bright reflection (the S reflector) generally interpreted as a tectonic Moho. The margin exhibits neither voluminous magmatism nor thick sediment piles to obscure the structures and the amount of extension. As such is represents an ideal location to study the process of continental breakup both through seismic imaging and potentially through drilling. Prestack depth migration of existing 2D profiles has strongly supported the interpretation of the S reflector as both a detachment and as the crust-mantle boundary; wide-angle seismic has also shown that the mantle beneath S is serpentinised. Despite the quality of the existing 2D seismic images, a number of competing models have been advanced to explain the formation of this margin, including sequential faulting, polyphase faulting, multiple detachments and the gravitational collapse of the margin over exhumed mantle. As these models, all developed for the Galicia margin, have been subsequently applied to other margins, distinguishing between them has implications not only for the structure of the Galicia margin but for the process of rifting through to breakup more generally. To address these issues in summer of 2013 we collected a 3D combined seismic reflection and wide-angle dataset over this margin. Here we present some of the results of ongoing processing of the 3D volume, focussing on the internal structure of some of the fault blocks that overlies the S detachment. 2D processing of the data shows a relatively simple series of tilted fault block, bound by west-dipping faults that detach downwards onto the bright S reflector. However, inspection of the 3D volume produced by 3D pre-stack time migration reveals that the fault blocks contain a complex set of sedimentary packages, with strata tilted to the east, west, north and south, each package bound by faults. Furthermore, the top of crustal basement appears in places to have acted as an extensional slip surface. We interpret the complex pattern of faulting and internal block deformation as the results of several phases of faulting, coupled with internal deformation and some late gravitational collapse, all components of some of the various models that have been applied to this margin.

  11. Combining 2D and 3D hand geometry features for biometric verification

    Microsoft Academic Search

    Vivek Kanhangad; Ajay Kumar; David Zhang

    2009-01-01

    Traditional hand geometry based personal verification systems offer limited performance and therefore suitable only for small scale applications. This paper investigates a new approach to achieve performance improvement for hand geometry systems by simultaneously acquiring three dimensional features from the presented hands. The proposed system utilizes a laser based 3D digitizer to acquire registered intensity and range images of the

  12. Full Wave Propagation Code in General 3D Geometry

    NASA Astrophysics Data System (ADS)

    Popovich, Pavel; Cooper, W. Anthony; Villard, Laurent

    2003-10-01

    A full-wave propagation code (LEMan) has been developed and tested for 3D plasma configurations. The code solves the Maxwell operator for inhomogeneous plasma with a given external antenna. The plasma-wave interaction is modelled with full cold plasma dielectric tensor with finite electron mass. Special care is taken to avoid numerical pollution of the discretised spectrum: the wave equation is reformulated in terms of electromagnetic potentials. The discretisation is implemented with finite elements radially and Fourier decomposition in poloidal and toroidal angles. The LEMan code uses the equilibrium metric in Boozer magnetic coordinates produced with TERPSICHORE. The Fourier formulation of the problem gives a possibility to largely reduce matrix construction time by minimizing the number of numerical integrations of the equilibrium coefficients. Several mirror- and helix-like configurations have been analysed showing the expected structure of the spectrum in the Alfven frequency range with characteristic gaps and eigenmodes. In the case of both poloidal and toroidal mode coupling (2-period QAS stellarator) the spectrum is very complicated, but a comparison with the corresponding cylindrical branches still helps to distinguish the main modes and mode conversion surfaces.

  13. Fault geometry and fault-zone development in mixed carbonate/clastic successions: Implications for reservoir management

    E-print Network

    Stell, John

    Fault geometry and fault-zone development in mixed carbonate/clastic successions: Implications Geological Survey) & David Richardson (Kier Mining) Overview Faults are key controlling elements of fluid flow within reservoirs. When faults undergo displacement, they change their fluid transmissibility

  14. 3D Geometry Reconstruction from Multiple Segmented Surface Descriptions Using Neuro-Fuzzy Similarity Measures

    Microsoft Academic Search

    Daniel Fischer; Peter Kohlhepp

    2000-01-01

    This paper presents a novel solution to the reconstruction of 3D geometry models from partial, segmented (2.5D or 3D) range views. First, the geometric fusion works entirely on sparse symbolic information, i.e. attributed surface graphs, rather than point data or triangulated meshes. Thus, new sensor data can always be integrated with an existing partial model available for symbolic action planning.

  15. Development of an algorithm to measure defect geometry using a 3D laser scanner

    Microsoft Academic Search

    S Kilambi; S M Tipton

    2012-01-01

    Current fatigue life prediction models for coiled tubing (CT) require accurate measurements of the defect geometry. Three-dimensional (3D) laser imaging has shown promise toward becoming a nondestructive, non-contacting method of surface defect characterization. Laser imaging provides a detailed photographic image of a flaw, in addition to a detailed 3D surface map from which its critical dimensions can be measured. This

  16. Multiview Geometry for Texture Mapping 2D Images Onto 3D Range Data Computer Vision and Pattern Recognition, 2006

    E-print Network

    Stamos, Ioannis

    digital photography. A system- atic way for registering 3D range scans and 2D images is thus essentialMultiview Geometry for Texture Mapping 2D Images Onto 3D Range Data Computer Vision and Pattern presents a system that integrates multiview geometry and automated 3D registration techniques for texture

  17. Uncertainty assessment of imaging techniques for the 3D reconstruction of stent geometry.

    PubMed

    Cosentino, Daria; Zwierzak, Iwona; Schievano, Silvia; Díaz-Zuccarini, Vanessa; Fenner, John W; Narracott, Andrew J

    2014-08-01

    This paper presents a quantitative assessment of uncertainty for the 3D reconstruction of stents. This study investigates a CP stent (Numed, USA) used in congenital heart disease applications with a focus on the variance in measurements of stent geometry. The stent was mounted on a model of patient implantation site geometry, reconstructed from magnetic resonance images, and imaged using micro-computed tomography (CT), conventional CT, biplane fluoroscopy and optical stereo-photogrammetry. Image data were post-processed to retrieve the 3D stent geometry. Stent strut length, separation angle and cell asymmetry were derived and repeatability was assessed for each technique along with variation in relation to ?CT data, assumed to represent the gold standard. The results demonstrate the performance of biplanar reconstruction methods is comparable with volumetric CT scans in evaluating 3D stent geometry. Uncertainty on the evaluation of strut length, separation angle and cell asymmetry using biplanar fluoroscopy is of the order ±0.2mm, 3° and 0.03, respectively. These results support the use of biplanar fluoroscopy for in vivo measurement of 3D stent geometry and provide quantitative assessment of uncertainty in the measurement of geometric parameters. PMID:24894028

  18. Semi-implicit finite volume scheme for image processing in 3D cylindrical geometry

    NASA Astrophysics Data System (ADS)

    Mikula, Karol; Sgallari, Fiorella

    2003-12-01

    Nowadays, 3D echocardiography is a well-known technique in medical diagnosis. Inexpensive echocardiographic acquisition devices are applied to scan 2D slices rotated along a prescribed direction. Then the discrete 3D image information is given on a cylindrical grid. Usually, this original discrete image intensity function is interpolated to a uniform rectangular grid and then numerical schemes for 3D image processing operations (e.g. nonlinear smoothing) in the uniform rectangular geometry are used. However, due to the generally large amount of noise present in echocardiographic images, the interpolation step can yield undesirable results. In this paper, we avoid this step and suggest a 3D finite volume method for image selective smoothing directly in the cylindrical image geometry. Specifically, we study a semi-implicit 3D cylindrical finite volume scheme for solving a Perona-Malik-type nonlinear diffusion equation and apply the scheme to 3D cylindrical echocardiographic images. The L?-stability and convergence of the scheme to the weak solution of the regularized Perona-Malik equation is proved.

  19. Reconstruction of 3-D road geometry from images for autonomous land vehicles

    Microsoft Academic Search

    K. Kanatani; K. Watanabe

    1990-01-01

    A novel algorithm for reconstructing 3-D road geometry from images is presented for the purpose of autonomously navigating land vehicles. The reconstruction is based on an idealized road model: a road is assumed to be generated by a horizontal line segment of a fixed length sweeping in the scene. The constraints that ideal road images must satisfy are expressed as

  20. Statistical mechanics of the 3D axisymmetric Euler equations in a Taylor-Couette geometry

    E-print Network

    Paris-Sud XI, Université de

    Statistical mechanics of the 3D axisymmetric Euler equations in a Taylor-Couette geometry Simon ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 Statistical mechanics of a simplified problem without helical correla- tions 9 3.1 Definition of the simplified problem . . . . . . . . . . . . . . . . . . . . . . 9 3.2 Statistical mechanics of the toroidal

  1. Multistatic passive radar geometry optimization for target 3D positioning accuracy

    Microsoft Academic Search

    Francesca Gumiero; Cinzia Nucciarone; Valeria Anastasio; Pierfrancesco Lombardo; Fabiola Colone

    2010-01-01

    The paper presents a design procedure for a multistatic passive radar system, that aims at its performance optimization, in terms of 3D positioning accuracy. Specifically, the proposed procedure considers the main features of the considered air traffic control scenario and the main physical and geometrical features of the passive radar receivers and guides the designer to select the geometry that

  2. Investigating 3D Geometry of Porous Media from High Resolution Images

    E-print Network

    New York at Stoney Brook, State University of

    Investigating 3D Geometry of Porous Media from High Resolution Images W. B. Lindquist and A Resolution Images W. B. Lindquist and A. Venkatarangan State University of New York at Stony Brook, Stony diameter core of basalt from a vesiculated lava flow imaged at 20 micron resolution. 1 Introduction

  3. An Integrated Background Model for Video Surveillance Based on Primal Sketch and 3D Scene Geometry

    E-print Network

    Zhu, Song Chun

    An Integrated Background Model for Video Surveillance Based on Primal Sketch and 3D Scene Geometry presents a novel integrated background model for video surveillance. Our model uses a primal sketch at pixel level, and the integrated video surveillance system at the object and tra- jectory level. 1

  4. Slip Surfaces in Fault Breccia From the Sierra Madre Fault Zone: Geometry and Mechanical Implications

    NASA Astrophysics Data System (ADS)

    Mordohai, P.; Dor, O.; Zechar, J.; Sammis, C. G.; Ben-Zion, Y.

    2003-12-01

    Fault breccia from the Sierra Madre Fault Zone is imaged using a new technique, resolving a highly detailed structure of internal slip surfaces with characteristic distribution of orientations and senses of slip. We excavated a 25x28x35 cm3 sample of brecciated granite from the hanging wall of the Sierra Madre fault near JPL, La Canada, California. The base of the sample was attached to the principal slip surface, dipping 40° to the NW, showing up-dip slip striations. The sample was carefully removed with known orientation while maintaining its integrity. We used a two camera digital imaging system developed in the Department of Electrical Engineering at USC. With the positions of the cameras and sample fixed, we progressively removed the outer layers of the specimen exposing the internal slip surfaces. Each slip plane was marked with a spot; a line was marked if slicknsides were observed, and a stereo photo taken. These 3D images were analyzed to give the normal to each slip plane and the tangent to each slip line. The slip surfaces are few millimeters to several centimeters wide. They branch and coalesce to create a dense micro- and meso-scale network. The polygons bounded by these surfaces are composed of powdered granite that maintains its original fabric. The surfaces are shiny, present clear slicknsides and have silky touch. Larger slip surfaces show macroscopic curvature producing roughness at various wavelengths. This curvature is comprised of the smaller slip planes that were marked for the imaging. We hypothesize that initial fracturing process created the small-scale planes which then coalescenced by rotation and abrasive wear to create the large surfaces. These large slip surfaces are generally sub-parallel to the fault strike and sub-perpendicular to its slip vector. Analysis of 196 planes indicates that the dip direction of 123 planes (63%) is between the east and the south, nearly opposite to the fault. Another 59 planes are dipping in the NE and SW quadrants, 43 of them trend to the ENE and to the SSW. Only 14 planes (7%) trend NW, sub-parallel to the fault. The distribution of inclinations covers the entire range, except for the planes that trend with the fault. Of these, 9 are sub-vertical and 3 are sub-horizontal. The slicknsides were imaged as lines in space but the senses of motion have not yet been determined. They are low-angle 3D lines with no consistent trend indicating mostly horizontal motion. The mechanical origin of this set of surfaces needs a further verification. While they are not consistent with Riedel shear geometry, the characteristics of the surfaces show that they accommodate a small amount of rotation that may reflect simple shear. This requires a relatively homogeneous stress field. As this is not necessarily the case, they might be of dynamic origin, reflecting the heterogeneity of a process-zone stress field ahead of the earthquake rupture. Finally, the dynamic reduction of normal stress during the passage of a rupture can control the formation of this geometry, but requires that the slicknsides (to be verified) will demonstrate a tensile regime.

  5. The 3D Velocity Structures beneath the Song Ma Fault Zone, North Vietnam

    NASA Astrophysics Data System (ADS)

    Wu, W. J.; Wen, S.; Tang, C. C.; Yeh, Y.; Phong, L. H.; Toan, D. V.; Chen, C.

    2014-12-01

    The Indochina area is a tectonic active region where creates complex topographies and tectonic structures. Especially, the Ma River shear zone plays an important role in understanding the mechanism and revolution of the escape process between the Indian plate and the Eurasian plate. In order to have better understanding the seismotectonic structures around the fault zone, this study has carried out a project to deploy 12 temporary broadband seismic stations around/near the Ma River area to record high quality waveform data. In this study, we adopt damping least-square inversion method to investigate the Vp structures and Vp/Vs ratios of the crust and upper mantle beneath the Ma River fault zone, northern Vietnam. From many studies, the velocity structure can be used as an indicator to identify the geometry of fault and precise the earthquake location. Therefore, the goal of this research is to analyze the degree of correlation between the velocity structure and the characteristics of the seismicity, and its tectonic implications. Finally the distribution of Vp/Vs ratio and its association with fault activities is also investigated. Our results indicate that the variation of velocity structure beneath the Ma River fault zone is caused by local geological structures, and the earthquake clusters are located between the Ma River fault and the Song-La fault in the northern Vietnam. Besides, the obtained focal mechanisms from the tomography inversion also exhibit that the orientations are northeast-southwest trending with normal faulting nearby the Ma river fault and should be highly correlation with local geological structures. Based on the analysis of focal mechanism solutions, this area is in extension status which is consistent with the geological survey. Finally, we find a dense cluster occurred in the bending segment of the Ma River fault, and according to the distribution of seismic events, there may exist a south-dipping fault in the southern part of Ma River fault. However, this argument needs to be investigated more in future study.

  6. Fault geometries in basement-induced wrench faulting under different initial stress states

    NASA Astrophysics Data System (ADS)

    Naylor, M. A.; Mandl, G.; Supesteijn, C. H. K.

    Scaled sandbox experiments were used to generate models for relative ages, dip, strike and three-dimensional shape of faults in basement-controlled wrench faulting. The basic fault sequence runs from early en échelon Riedel shears and splay faults through 'lower-angle' shears to P shears. The Riedel shears are concave upwards and define a tulip structure in cross-section. In three dimensions, each Riedel shear has a helicoidal form. The sequence of faults and three-dimensional geometry are rationalized in terms of the prevailing stress field and Coulomb-Mohr theory of shear failure. The stress state in the sedimentary overburden before wrenching begins has a substantial influence on the fault geometries and on the final complexity of the fault zone. With the maximum compressive stress (? 1) initially parallel to the basement fault (transtension), Riedel shears are only slightly en échelon, sub-parallel to the basement fault, steeply dipping with a reduced helicoidal aspect. Conversely, with ? 1 initially perpendicular to the basement fault (transpression), Riedel shears are strongly oblique to the basement fault strike, have lower dips and an exaggerated helicoidal form; the final fault zone is both wide and complex. We find good agreement between the models and both mechanical theory and natural examples of wrench faulting.

  7. Linearized perturbation analysis of along-strike nonuniformity of slip in 3D fault models with depth-variable properties

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Rice, J. R.

    2004-12-01

    In our three dimensional modeling [EOS, 2003; JGR submitted, 2004] of long term loading and earthquake sequences on a shallow subduction fault, with depth-variable rate and state friction properties, we found the response was perturbed into a strongly nonuniform slip mode along strike by introducing small along-strike perturbations in friction properties. Similar results were found in some cases of 3D strike slip modeling by Rice and Ben-Zion [PNAS, 1996]. To explore this further, we report results of linearized perturbation analyses for two versions, ``ageing'' (or ``slowness'') and ``slip'', of the friction laws. The 3D solution vector S(x,z,t), where x,z are the respective along-strike and downdip coordinates in the fault plane, consists of shear stress ? (x,z,t), slip ? (x,z,t) and state variable ? (x,z,t). It can be written as the sum of a 2D solution vector S0(z,t), which is subject to initial conditions S0(z,0), and an infinitesimal variation Re[S1(z,t) exp(2 i ? x / ? )], where ? is a perturbation wavelength. In our case the friction properties and external driving are such that S0(z,t) describes a sequence of earthquakes separated by long interseismic loading intervals during which slow creep slippage occurs, like in the Tse and Rice [JGR, 1986] type of 2D modeling. Linearizing the governing equations in S1(z,t) (giving a nonautonomous system, because coefficients depend on S0(z,t)), we can calculate the evolution of S1 for a given unperturbed history S0(z,t) and initial conditions S1(z,0). For both pure thrust and pure strike-slip fault geometries, we found that there is a critical ratio ? crit/h*, which seems to determine the stability of along-strike response; h* is the minimum neutrally stable downdip slip patch size, according to rate and state stability theory for perturbation of steady slip. When ? crit/h* is greater than the critical value, ? ? 1(z,t)/? t and ? 1(z,t) grow to significantly large values; when less than the critical value, the perturbations decay with time. Our calculations give the critical ratio around 4 to 6. Such a transition is confirmed by our fully nonlinear 3D simulations. However, the perturbation growth history (which is not a simple exponential in t) depends on the position at depth. Fault parts which are in the well-locked seismogenic zone have earlier rise time and faster growth rate than those in the velocity-strengthening regions. Remarkable resistance to break up into non-uniform strike slip was observed by Rice and Ben-Zion when using the slip version of friction law. Linearized perturbation analysis with that version shows, as compared to the ageing version with the same h*, that the ? crit is similar but that the perturbation growth is much slower. This might explain why along-strike heterogeneity of slip for that version was much less than for the ageing version. However, for the 3D thrust fault case, we have not found significant qualitative difference for the two laws; both show break-up of the slip distribution along strike.

  8. Small-scale faulting in the Upper Cretaceous of the Groningen block (The Netherlands): 3D seismic interpretation, fault plane analysis and regional paleostress

    Microsoft Academic Search

    Heijn van Gent; Stefan Back; Janos L. Urai; Peter Kukla

    2010-01-01

    Over the last years, field-based studies have shown that fault surfaces can exhibit a considerable self-affine topography. It is reasonable to assume that similar undulations are also present in fault interpretations from 3D reflection seismic data, however both the interpretation uncertainty and geophysical resolution limits hinder their analysis. This study analyses a set of small-scale, non-reactivated faults in the Upper

  9. 3D geometry and evolutionary sequence of fold-thrust systems in NW Taiwan

    NASA Astrophysics Data System (ADS)

    Chang, Hao-Yun; Yang, Kenn-Ming; Hsieh, Ching-Yun; Yang, Tzu-Ruei; Chuang, Hui-Ju; Chen, Yi-Ju

    2015-04-01

    During the arc-continental collision from the Pliocene to the Pleistocene, two sets of fold-and-thrust system developed in NW Taiwan, a series of NNE-SSW striking low-angle thrust faults and their related folds (set A) and the other series of NEE-SWW striking high-angle thrust faults and their related folds (set B). The latter one cuts the former one and extends forelandward. The geometry of intersection and development sequence of both sets of structures are still in debate. In this study, we utilized a grid of seismic profiles to constrain our interpretation on the subsurface structural geometry of the two structural sets, which then was tested by structural restoration. We also made some simulations on the formation of fault-related folds by trishear modeling. The influence of normal fault reactivation on and the transitional relationships among the structures were investigated to establish an evolutionary sequence for the fold-and thrust systems of NW Taiwan. The strike of set A is NNE-SSW in the northern part of the study area but becomes N-S to the south. The location of the strike change is cut by a NEE-SWW high-angle fault of set B. According to the seismic interpretation, shallower anticline is asymmetric whereas deeper anticline is symmetric. The low-angle thrust of set A extends to the south and transfers into high-angle where it is cut by the high-angle fault of set B. The trishear model suggests that the shallower anticline resulted from low-angle fault thrusting in early period, whereas the deeper one was caused by basal detachment faulting in the late stage. Seismic interpretation also reveals an asymmetric and gentle fold cut by a high-angle thrust fault of set B. The result of trishear modeling indicates that the anticline was formed by slip along a high angle thrust, which is a low-angle fault in the deep but turns into high angle along a pre-existing normal fault up to the surface. In summary, the development of the shallower anticline of set A is controlled by low-angle thrusting while the deeper one by basal detachment faulting. The anticlines of set B are not only controlled by the high-angle faulting but also influenced by the deeper low-angle thrusting. The depth of low-angle thrust fault of set B in the foreland is shallower than that of basal detachment fault of set A near the orogen. Such spatial variation in thrust shape suggests that set B was formed earlier than set A and, therefore, both sets of thrust and related structures can be viewed as an out-of-sequence development.

  10. Black silicon with sub-percent reflectivity: Influence of the 3D texturization geometry

    Microsoft Academic Search

    K. N. Nguyen; D. Abi-Saab; P. Basset; E. Richalot; F. Marty; D. Angelescu; Y. Leprince-Wang; T. Bourouina

    2011-01-01

    In this paper we study the impact of the three-dimensional geometry of a micro\\/nanostructured silicon surface on its reflectivity under incident electromagnetic (EM) illumination. We simulate the optical reflectance of 3D micro\\/nano silicon cones of different dimensions. Based on the favorable simulation results, maskless textured silicon, called “black silicon” is processed by deep reactive ion etching (DRIE) under cryogenic temperatures.

  11. 3D Bioprinting of complex channels-Effects of material, orientation, geometry, and cell embedding.

    PubMed

    Wüst, Silke; Müller, Ralph; Hofmann, Sandra

    2015-08-01

    Creating filled or hollow channels within 3D tissues has become increasingly important in tissue engineering. Channels can serve as vasculature enhancing medium perfusion or as conduits for nerve regeneration. The 3D biofabrication seems to be a promising method to generate these structures within 3D constructs layer-by-layer. In this study, geometry and interface of bioprinted channels were investigated with micro-computed tomography and fluorescent imaging. In filament printing, size and shape of printed channels are influenced by their orientation, which was analyzed by printing horizontally and vertically aligned channels, and by the ink, which was evaluated by comparing channels printed with an alginate-gelatin hydrogel or with an emulsion. The influence of geometry and cell-embedding in the hydrogel on feature size and shape was investigated by printing more complex channels. The generation of hollow channels, induced through leaching of a support phase, was monitored over time. Horizontally aligned channels provided 16× smaller cross-sectional areas than channels in vertical orientation. The smallest feature size of hydrogel filaments was twice as large compared to emulsion filaments. Feature size and shape depended on the geometry but did not alter when living cells were embedded. With that knowledge, channels can be consciously tailored to the particular needs. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 2558-2570, 2015. PMID:25524726

  12. Reliable and Fault-Tolerant Software-Defined Network Operations Scheme for Remote 3D Printing

    NASA Astrophysics Data System (ADS)

    Kim, Dongkyun; Gil, Joon-Min

    2015-03-01

    The recent wide expansion of applicable three-dimensional (3D) printing and software-defined networking (SDN) technologies has led to a great deal of attention being focused on efficient remote control of manufacturing processes. SDN is a renowned paradigm for network softwarization, which has helped facilitate remote manufacturing in association with high network performance, since SDN is designed to control network paths and traffic flows, guaranteeing improved quality of services by obtaining network requests from end-applications on demand through the separated SDN controller or control plane. However, current SDN approaches are generally focused on the controls and automation of the networks, which indicates that there is a lack of management plane development designed for a reliable and fault-tolerant SDN environment. Therefore, in addition to the inherent advantage of SDN, this paper proposes a new software-defined network operations center (SD-NOC) architecture to strengthen the reliability and fault-tolerance of SDN in terms of network operations and management in particular. The cooperation and orchestration between SDN and SD-NOC are also introduced for the SDN failover processes based on four principal SDN breakdown scenarios derived from the failures of the controller, SDN nodes, and connected links. The abovementioned SDN troubles significantly reduce the network reachability to remote devices (e.g., 3D printers, super high-definition cameras, etc.) and the reliability of relevant control processes. Our performance consideration and analysis results show that the proposed scheme can shrink operations and management overheads of SDN, which leads to the enhancement of responsiveness and reliability of SDN for remote 3D printing and control processes.

  13. Electromagnetic constraints on strike-slip fault geometry-The Fraser River fault system

    E-print Network

    Jones, Alan G.

    Geoscience Centre, Sidney, British Columbia V8L 4B2, Canada Rob G. Ellis Department of GeophysicsElectromagnetic constraints on strike-slip fault geometry-The Fraser River fault system Alan G and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada ABSTRACT Magnetote

  14. Reconstruction of 3-D cloud geometry using a scanning cloud radar

    NASA Astrophysics Data System (ADS)

    Ewald, F.; Winkler, C.; Zinner, T.

    2014-11-01

    Clouds are one of the main reasons of uncertainties in the forecasts of weather and climate. In part, this is due to limitations of remote sensing of cloud microphysics. Present approaches often use passive spectral measurements for the remote sensing of cloud microphysical parameters. Large uncertainties are introduced by three dimensional (3-D) radiative transfer effects and cloud inhomogeneities. Such effects are largely caused by unknown orientation of cloud sides or by shadowed areas on the cloud. Passive ground based remote sensing of cloud properties at high spatial resolution could be improved crucially with this kind of additional knowledge of cloud geometry. To this end, a method for the accurate reconstruction of 3-D cloud geometry from cloud radar measurements is developed in this work. Using a radar simulator and simulated passive measurements of static LES model clouds, the effects of different radar scan resolutions and varying interpolation methods are evaluated. In reality a trade-off between scan resolution and scan duration has to be found as clouds are changing quickly. A reasonable choice is a scan resolution of 1 to 2°. The most suitable interpolation procedure identified is the barycentric interpolation method. The 3-D reconstruction method is demonstrated using radar scans of convective cloud cases with the Munich miraMACS, a 35 GHz scanning cloud radar. As a successful proof of concept, camera imagery collected at the radar location is reproduced for the observed cloud cases via 3-D volume reconstruction and 3-D radiative transfer simulation. Data sets provided by the presented reconstruction method will aid passive spectral ground-based measurements of cloud sides to retrieve microphysical parameters.

  15. Incorporating fault-slip constraints in 3D geomechanical restoration with application to restraining bend systems in the deep-water Niger Delta

    NASA Astrophysics Data System (ADS)

    Durand-Riard, P.; Shaw, J. H.; Plesch, A.

    2011-12-01

    In the past few years, geomechanical restoration has emerged as a new method of structural analysis and has been successfully applied to analyze thrust and normal fault systems. However, the restoration of strike- and oblique fault systems using the restoration workflow does not generally recover sufficient amounts of strike-slip, thus leading to unsatisfactory results. In order to better constrain the restoration of such systems, we propose to combine classical boundary conditions with new fault-slip constraints. We investigate several possible sets of constraints by restoring a synthetic balanced model of a restraining bend system that includes a fold above an oblique-slip fault connecting two right-lateral strike-slip faults. The restored geometries and corresponding strain distribution are compared, showing that the best results are obtained by constraining either the walls of the model or the fault line with known gradients of slip. However, when dealing with natural structures where the slip is not known everywhere along the fault, a more realistic approach consists in constraining only piercing points, which also leads to acceptable results. We then apply this approach to a restraining bend located in the outer fold-and-thrust belt in the deepwater Niger Delta. Although the deformation in the region is largely focused on thrust-fault systems, gradients in the shortening are also accommodated in the northern part of the Delta toe by the development of transport-parallel tear faults. In some locations, steps or relays between tear fault splays result in restraining bend architectures. The high quality of the seismic data in the region allows us to identify and map in detail one of these structures, and to image several channels offsets on the horizons. This provides us fault-slip constraints that are used in our new restoration workflow, yielding an improved assessment of the deformation required to accommodate the tear-faults displacement within the restraining bends. The use of fault-slip constraints combined with classical boundary conditions offers a realistic approach for using geologic observations to constrain 3D restorations of strike- and oblique slip fault systems, enhancing the effectiveness of these methods in addressing the associated deformation.

  16. The Derivation of Fault Volumetric Properties from 3D Trace Maps Using Outcrop Constrained Discrete Fracture Network Models

    NASA Astrophysics Data System (ADS)

    Hodgetts, David; Seers, Thomas

    2015-04-01

    Fault systems are important structural elements within many petroleum reservoirs, acting as potential conduits, baffles or barriers to hydrocarbon migration. Large, seismic-scale faults often serve as reservoir bounding seals, forming structural traps which have proved to be prolific plays in many petroleum provinces. Though inconspicuous within most seismic datasets, smaller subsidiary faults, commonly within the damage zones of parent structures, may also play an important role. These smaller faults typically form narrow, tabular low permeability zones which serve to compartmentalize the reservoir, negatively impacting upon hydrocarbon recovery. Though considerable improvements have been made in the visualization field to reservoir-scale fault systems with the advent of 3D seismic surveys, the occlusion of smaller scale faults in such datasets is a source of significant uncertainty during prospect evaluation. The limited capacity of conventional subsurface datasets to probe the spatial distribution of these smaller scale faults has given rise to a large number of outcrop based studies, allowing their intensity, connectivity and size distributions to be explored in detail. Whilst these studies have yielded an improved theoretical understanding of the style and distribution of sub-seismic scale faults, the ability to transform observations from outcrop to quantities that are relatable to reservoir volumes remains elusive. These issues arise from the fact that outcrops essentially offer a pseudo-3D window into the rock volume, making the extrapolation of surficial fault properties such as areal density (fracture length per unit area: P21), to equivalent volumetric measures (i.e. fracture area per unit volume: P32) applicable to fracture modelling extremely challenging. Here, we demonstrate an approach which harnesses advances in the extraction of 3D trace maps from surface reconstructions using calibrated image sequences, in combination with a novel semi-deterministic, outcrop constrained discrete fracture network modeling code to derive volumetric fault intensity measures (fault area per unit volume / fault volume per unit volume). Producing per-vertex measures of volumetric intensity; our method captures the spatial variability in 3D fault density across a surveyed outcrop, enabling first order controls to be probed. We demonstrate our approach on pervasively faulted exposures of a Permian aged reservoir analogue from the Vale of Eden Basin, UK.

  17. 3D Digital Surveying and Modelling of Cave Geometry: Application to Paleolithic Rock Art

    PubMed Central

    González-Aguilera, Diego; Muñoz-Nieto, Angel; Gómez-Lahoz, Javier; Herrero-Pascual, Jesus; Gutierrez-Alonso, Gabriel

    2009-01-01

    3D digital surveying and modelling of cave geometry represents a relevant approach for research, management and preservation of our cultural and geological legacy. In this paper, a multi-sensor approach based on a terrestrial laser scanner, a high-resolution digital camera and a total station is presented. Two emblematic caves of Paleolithic human occupation and situated in northern Spain, “Las Caldas” and “Peña de Candamo”, have been chosen to put in practise this approach. As a result, an integral and multi-scalable 3D model is generated which may allow other scientists, pre-historians, geologists…, to work on two different levels, integrating different Paleolithic Art datasets: (1) a basic level based on the accurate and metric support provided by the laser scanner; and (2) a advanced level using the range and image-based modelling. PMID:22399958

  18. High resolution 3D laser scanner measurements of a strike-slip fault quantify its morphological anisotropy at all scales

    Microsoft Academic Search

    François Renard; Christophe Voisin; David Marsan; Jean Schmittbuhl

    2006-01-01

    The surface roughness of a recently exhumed strike-slip fault plane has been measured by three independent 3D portable laser scanners. Digital elevation models of several fault surface areas, from 1 m2 to 600 m2, have been measured at a resolution ranging from 5 mm to 80 mm. Out of plane height fluctuations are described by non-Gaussian distribution with exponential long

  19. Early evolution of an extensional monocline by a propagating normal fault: 3D analysis from combined eld study and numerical modeling

    E-print Network

    Hilley, George

    Early evolution of an extensional monocline by a propagating normal fault: 3D analysis from propagation of normal faults. Where normal faults reach the surface, the footwall contains undisturbed, gently dipping strata, whereas the hanging wall is a highly deformed zone that contains fractured and faulted

  20. Akaso Field, Nigeria: Use of integrated 3-D seismic, fault slicing, clay smearing, and RFT pressure data on fault trapping and dynamic leakage

    SciTech Connect

    Jev, B.I.; Watts, N.L.; Wilkie, J.T. (Shell Petroleum Development Co., Lagos (Nigeria)); Kaars-Sijpesteijn, C.H. (Shell Internationale Petroleum Maatschappij, Den Haag (Netherlands)); Peters, M.P.A.M. (Beb Erdoel und Erdgas GMBH, Hanover (Germany))

    1993-08-01

    The Akaso field [STOIIP 78 [times] 10[sup 6] m[sup 3] (401 million STB)] of the eastern Niger Delta is separated from the large Cawthorne Channel field [STOIIP 208 [times]10[sup 6] m[sup 3] (1307 million STB)] normal fault. In 1989, three-dimensional (3-D) seismic data acquired and interpreted over the field revealed a subtle splinter or backsplit fault off this major antithetic fault west of the main Akaso field. Behind this backsplit fault the authors observed stacked amplitude anomalies. These anomalies extended to the structural spillpoint defined against the Akaso backsplit faults. Fault splicing and clay smear studies of the backsplit and main antithetic fault indicated strong seal potential with possible [open quotes]leak windows[close quotes] along the fault planes. In 1989, the sealing potentials of the western end of the Akaso boundary fault were fully confirmed by a deviated appraisal well, which found a STOIIP of 29 [times] 10[sup 6] (183 million STB) in a series of stacked footwall closures. The initial trapping potential of this major antithetic normal fault can be contrasted with its subsequent behavior during depletion by using RFT data acquired in a series of development wells drilled in 1990 in the main Akaso structure at the eastern end of the antithetic fault. Here, major stacked columns of oil and gas are trapped and sealed by the antithetic fault, but we identified and sealed by the antithetic fault, but the authors identified evidence of subsequent leakage due to production effects from the adjacent Cawthorne Channel field. Depletion of the unproduced Akaso G sands was found to be due to production from the juxtaposed E sands of the adjacent Cawthorne Channel field, thus we inferred dynamic fault leakage. The Akaso field represents a prime example of the trapping potential of a clay-smeared fault and its subsequent leakage during differential depletion. 18 refs., 11 figs.

  1. Landslide subsurface slip geometry inferred from 3-D surface displacement fields

    NASA Astrophysics Data System (ADS)

    Aryal, Arjun; Brooks, Benjamin A.; Reid, Mark E.

    2015-03-01

    The stability of many large landslides is determined in part by deformation along buried, often inaccessible, slip surfaces. Factors such as infiltrating rainfall on the slip surface lead to stability changes. Yet characterizing the depth and shape of this slip surface is challenging. Here we examine the hypothesis that the subsurface slip geometry can be constrained by ground surface displacements in concert with two, mechanically distinct, forward models. We estimate a 3-D ground displacement field for the slow-moving Cleveland Corral landslide in California using repeat terrestrial laser scanner data. We test the efficacy of two models to estimate slip depth and slip magnitude of the slide—a 2-D balanced cross-section method and an elastic dislocation model. The estimated slip surface depth using both methods matches in situ observations from shear rods installed in the slide within the ±0.45 m misfit indicating that these are valuable approaches for investigating landslide geometry and slip behavior.

  2. 3D Modelling of Seismically Active Parts of Underground Faults via Seismic Data Mining

    NASA Astrophysics Data System (ADS)

    Frantzeskakis, Theofanis; Konstantaras, Anthony

    2015-04-01

    During the last few years rapid steps have been taken towards drilling for oil in the western Mediterranean sea. Since most of the countries in the region benefit mainly from tourism and considering that the Mediterranean is a closed sea only replenishing its water once every ninety years careful measures are being taken to ensure safe drilling. In that concept this research work attempts to derive a three dimensional model of the seismically active parts of the underlying underground faults in areas of petroleum interest. For that purpose seismic spatio-temporal clustering has been applied to seismic data to identify potential distinct seismic regions in the area of interest. Results have been coalesced with two dimensional maps of underground faults from past surveys and seismic epicentres, having followed careful reallocation processing, have been used to provide information regarding the vertical extent of multiple underground faults in the region of interest. The end product is a three dimensional map of the possible underground location and extent of the seismically active parts of underground faults. Indexing terms: underground faults modelling, seismic data mining, 3D visualisation, active seismic source mapping, seismic hazard evaluation, dangerous phenomena modelling Acknowledgment This research work is supported by the ESPA Operational Programme, Education and Life Long Learning, Students Practical Placement Initiative. References [1] Alves, T.M., Kokinou, E. and Zodiatis, G.: 'A three-step model to assess shoreline and offshore susceptibility to oil spills: The South Aegean (Crete) as an analogue for confined marine basins', Marine Pollution Bulletin, In Press, 2014 [2] Ciappa, A., Costabile, S.: 'Oil spill hazard assessment using a reverse trajectory method for the Egadi marine protected area (Central Mediterranean Sea)', Marine Pollution Bulletin, vol. 84 (1-2), pp. 44-55, 2014 [3] Ganas, A., Karastathis, V., Moshou, A., Valkaniotis, S., Mouzakiotis, E. and Papathanassiou, G.: 'Aftershock relocation and frequency-size distribution, stress inversion and seismotectonic setting of the 7 August 2013 M=5.4 earthquake in Kallidromon Mountain, central Greece', Tectonophysics, vol. 617, pp. 101-113, 2014 [4] Maravelakis, E., Bilalis, N., Mantzorou, I., Konstantaras, A. and Antoniadis, A.: '3D modelling of the oldest olive tree of the world', International Journal Of Computational Engineering Research, vol. 2 (2), pp. 340-347, 2012 [5] Konstantaras, A., Katsifarakis, E, Maravelakis, E, Skounakis, E, Kokkinos, E. and Karapidakis, E.: 'Intelligent spatial-clustering of seismicity in the vicinity of the Hellenic seismic arc', Earth Science Research, vol. 1 (2), pp. 1- 10, 2012 [6] Georgoulas, G., Konstantaras, A., Katsifarakis, E., Stylios, C., Maravelakis, E and Vachtsevanos, G.: 'Seismic-mass" density-based algorithm for spatio-temporal clustering', Expert Systems with Applications, vol. 40 (10), pp. 4183-4189, 2013 [7] Konstantaras, A.: 'Classification of Distinct Seismic Regions and Regional Temporal Modelling of Seismicity in the Vicinity of the Hellenic Seismic Arc', Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of', vol. 99, pp. 1-7, 2013

  3. On horizontal resolution for seismic acquisition geometries in complex 3D media

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Fu, Li-Yun

    2014-09-01

    Spatial sampling has a crucial influence on the horizontal resolution of seismic imaging, but how to quantify the influence is still controversial especially in complex media. Most of the studies on horizontal resolution focus on the measurement of wavelet widths for seismic migration, but neglect to evaluate the effect of side-lobe perturbations on spatial resolution. The side-lobe effect, as a migration noise, is important for seismic imaging in complex media. In this article, with focal beam analysis, we define two parameters to represent the horizontal resolution of an acquisition geometry: the width of the main lobe (WML) along the inline and crossline directions and the ratio of the main-lobe amplitude to the total amplitude (RMT) in a focal beam. We provide examples of typical acquisition geometries to show how spatial sampling affects the horizontal resolution, measured in terms of WML and RMT values. WML defines the horizontal resolution to image the target, whereas RMT describes the clarity of the imaging. Migration noise reduces with increasing RMT, indirectly improving both the vertical and horizontal resolutions of seismic imaging. Case studies of seismic migration with 3D seismic data from an oil field of China, demonstrate how the acquisition geometries with different WML and RMT values influence the performance of seismic imaging. Prior WML and RMT analyses to predict the quality of acquired datasets can optimize acquisition geometries before the implementation of seismic acquisition.

  4. Geometry of Thrust Faults Beneath Amenthes Rupes, Mars

    NASA Technical Reports Server (NTRS)

    Vidal, A.; Mueller, K. M.; Golombek, M. P.

    2005-01-01

    Amenthes Rupes is a 380 km-long lobate fault scarp located in the eastern hemisphere of Mars near the dichotomy boundary. The scarp is marked by about 1 km of vertical separation across a northeast dipping thrust fault (top to the SW) and offsets heavily-cratered terrain of Late Noachian age, the visible portion of which was in place by 3.92 Ga and the buried portion in place between 4.08 and 4.27 Ga. The timing of scarp formation is difficult to closely constrain. Previous geologic mapping shows that near the northern end of Amenthes Rupes, Hesperian age basalts terminate at the scarp, suggesting that fault slip predated the emplacement of these flows at 3.69 to 3.9 Ga. Maxwell and McGill also suggest the faulting ceased before the final emplacement of the Late Hesperian lavas on Isidis Planitia. The trend of the faults at Amenthes, like many thrust faults at the dichotomy boundary, parallels the boundary itself. Schultz and Watters used a dislocation modeling program to match surface topography and vertical offset of the scarp at Amenthes Rupes, varying the dip and depth of faulting, assuming a slip of 1.5 km on the fault. They modeled faulting below Amenthes Rupes as having a dip of between 25 and 30 degrees and a depth of 25 to 35 km, based on the best match to topography. Assuming a 25 degree dip and surface measurements of vertical offset of between 0.3 and 1.2 km, Watters later estimated the maximum displacement on the Amenthes Rupes fault to be 2.90 km. However, these studies did not determine the geometry of the thrust using quantitative constraints that included shortening estimates. Amenthes Rupes deforms large preexisting impact craters. We use these craters to constrain shortening across the scarp and combine this with vertical separation to infer fault geometry. Fault dip was also estimated using measurements of scarp morphology. Measurements were based on 460 m (1/128 per pixel) digital elevation data from the Mars Orbiter Laser Altimeter (MOLA), an instrument on the Mars Global Surveyor (MGS) satellite.

  5. SU-E-J-128: 3D Surface Reconstruction of a Patient Using Epipolar Geometry

    SciTech Connect

    Kotoku, J; Nakabayashi, S; Kumagai, S; Ishibashi, T; Kobayashi, T [Teikyo University, Itabashi-ku, Tokyo (Japan); Haga, A; Saotome, N [University of Tokyo Hospital, Bunkyo-ku, Tokyo (Japan); Arai, N [Teikyo University Hospital, Itabashi-ku, Tokyo (Japan)

    2014-06-01

    Purpose: To obtain a 3D surface data of a patient in a non-invasive way can substantially reduce the effort for the registration of patient in radiation therapy. To achieve this goal, we introduced the multiple view stereo technique, which is known to be used in a 'photo tourism' on the internet. Methods: 70 Images were taken with a digital single-lens reflex camera from different angles and positions. The camera positions and angles were inferred later in the reconstruction step. A sparse 3D reconstruction model was locating by SIFT features, which is robust for rotation and shift variance, in each image. We then found a set of correspondences between pairs of images by computing the fundamental matrix using the eight-point algorithm with RANSAC. After the pair matching, we optimized the parameter including camera positions to minimize the reprojection error by use of bundle adjustment technique (non-linear optimization). As a final step, we performed dense reconstruction and associate a color with each point using the library of PMVS. Results: Surface data were reconstructed well by visual inspection. The human skin is reconstructed well, althogh the reconstruction was time-consuming for direct use in daily clinical practice. Conclusion: 3D reconstruction using multi view stereo geometry is a promising tool for reducing the effort of patient setup. This work was supported by JSPS KAKENHI(25861128)

  6. Predicting band structure of 3D mechanical metamaterials with complex geometry via XFEM

    NASA Astrophysics Data System (ADS)

    Zhao, Jifeng; Li, Ying; Liu, Wing Kam

    2015-04-01

    Band structure characterizes the most important property of mechanical metamaterials. However, predicting the band structure of 3D metamaterials with complex microstructures through direct numerical simulation (DNS) is computationally inefficient due to the complexity of meshing. To overcome this issue, an extended finite element method (XFEM)-based method is developed to predict 3D metamaterial band structures. Since the microstructure and material interface are implicitly resolved by the level-set function embedded in the XFEM formulation, a non-conforming (such as uniform) mesh is used in the proposed method to avoid the difficulties in meshing complex geometries. The accuracy and mesh convergence of the proposed method have been validated and verified by studying the band structure of a spherical particle embedded in a cube and comparing the results with DNS. The band structures of 3D metamaterials with different microstructures have been studied using the proposed method with the same finite element mesh, indicating the flexibility of this method. This XFEM-based method opens new opportunities in design and optimization of mechanical metamaterials with target functions, e.g. location and width of the band gap, by eliminating the iterative procedure of re-building and re-meshing microstructures that is required by classical DNS type of methods.

  7. Development of an algorithm to measure defect geometry using a 3D laser scanner

    NASA Astrophysics Data System (ADS)

    Kilambi, S.; Tipton, S. M.

    2012-08-01

    Current fatigue life prediction models for coiled tubing (CT) require accurate measurements of the defect geometry. Three-dimensional (3D) laser imaging has shown promise toward becoming a nondestructive, non-contacting method of surface defect characterization. Laser imaging provides a detailed photographic image of a flaw, in addition to a detailed 3D surface map from which its critical dimensions can be measured. This paper describes algorithms to determine defect characteristics, specifically depth, width, length and projected cross-sectional area. Curve-fitting methods were compared and implicit algebraic fits have higher probability of convergence compared to explicit geometric fits. Among the algebraic fits, the Taubin circle fit has the least error. The algorithm was able to extract the dimensions of the flaw geometry from the scanned data of CT to within a tolerance of about 0.127 mm, close to the tolerance specified for the laser scanner itself, compared to measurements made using traveling microscopes. The algorithm computes the projected surface area of the flaw, which could previously only be estimated from the dimension measurements and the assumptions made about cutter shape. Although shadows compromised the accuracy of the shape characterization, especially for deep and narrow flaws, the results indicate that the algorithm with laser scanner can be used for non-destructive evaluation of CT in the oil field industry. Further work is needed to improve accuracy, to eliminate shadow effects and to reduce radial deviation.

  8. Amoeboid migration mode adaption in quasi-3D spatial density gradients of varying lattice geometry

    NASA Astrophysics Data System (ADS)

    Gorelashvili, Mari; Emmert, Martin; Hodeck, Kai F.; Heinrich, Doris

    2014-07-01

    Cell migration processes are controlled by sensitive interaction with external cues such as topographic structures of the cell’s environment. Here, we present systematically controlled assays to investigate the specific effects of spatial density and local geometry of topographic structure on amoeboid migration of Dictyostelium discoideum cells. This is realized by well-controlled fabrication of quasi-3D pillar fields exhibiting a systematic variation of inter-pillar distance and pillar lattice geometry. By time-resolved local mean-squared displacement analysis of amoeboid migration, we can extract motility parameters in order to elucidate the details of amoeboid migration mechanisms and consolidate them in a two-state contact-controlled motility model, distinguishing directed and random phases. Specifically, we find that directed pillar-to-pillar runs are found preferably in high pillar density regions, and cells in directed motion states sense pillars as attractive topographic stimuli. In contrast, cell motion in random probing states is inhibited by high pillar density, where pillars act as obstacles for cell motion. In a gradient spatial density, these mechanisms lead to topographic guidance of cells, with a general trend towards a regime of inter-pillar spacing close to the cell diameter. In locally anisotropic pillar environments, cell migration is often found to be damped due to competing attraction by different pillars in close proximity and due to lack of other potential stimuli in the vicinity of the cell. Further, we demonstrate topographic cell guidance reflecting the lattice geometry of the quasi-3D environment by distinct preferences in migration direction. Our findings allow to specifically control amoeboid cell migration by purely topographic effects and thus, to induce active cell guidance. These tools hold prospects for medical applications like improved wound treatment, or invasion assays for immune cells.

  9. Rapid, accurate improvement in 3D mask representation via input geometry optimization and crosstalk

    NASA Astrophysics Data System (ADS)

    Fryer, David; Lam, Michael; Adam, Kostas; Clifford, Chris; Oliver, Mike; Zuniga, Christian; Sturtevant, John; Wang, ChangAn; Mansfield, Scott

    2014-03-01

    This paper extends the state of the art by demonstrating performance improvements in the Domain Decomposition Method (DDM) from a physical perturbation of the input mask geometry. Results from four testcases demonstrate that small, direct modifications in the input mask stack slope and edge location can result in model calibration and verification accuracy benefit of up to 30%. All final mask optimization results from this approach are shown to be valid within measurement accuracy of the dimensions expected from manufacture. We highlight the benefits of a more accurate description of the 3D EMF near field with crosstalk in model calibration and impact as a function of mask dimensions. The result is a useful technique to align DDM mask model accuracy with physical mask dimensions and scattering via model calibration.

  10. Elements for measuring the complexity of 3D structural models: Connectivity and geometry

    NASA Astrophysics Data System (ADS)

    Pellerin, Jeanne; Caumon, Guillaume; Julio, Charline; Mejia-Herrera, Pablo; Botella, Arnaud

    2015-03-01

    The reliable modeling of three-dimensional complex geological structures can have a major impact on forecasting and managing natural resources and on predicting seismic and geomechanical hazards. However, the qualification of a model as structurally complex is often qualitative and subjective making the comparison of the capabilities and performances of various geomodeling methods or software difficult. In this paper, we consider the notion of structural complexity from a geometrical point of view and argue that it can be characterized using general metrics computed on three-dimensional sealed structural models. We propose global and local measures of the connectivity and of the geometry of the model components and show how they permit to classify nine 3D synthetic structural models. Depending on the complexity elements favored, the classification varies. The models we introduce could be used as benchmark models for geomodeling algorithms.

  11. Radiation in a Closed 3-D Universe Reveals its Present Geometry and its Past Evolution

    E-print Network

    Charles B. Leffert

    2001-06-19

    In previous papers, predictions of the new "Spatial Condensation (SC-)" cosmological model were presented on the (1) foundations, (2) new source of gravity, and (3) large-scale structure. In this paper predictions will include new physical features that are due mostly to the postulated geometry of our closed 3-D universe. Knowledge of the past universe is obtained from its many types of radiation that travel to our instruments on great circles of our expanding 3-sphere. Adding the fourth spatial dimension greatly increases our understanding of the concepts of emission and reception distances of the sources and 4-D trajectory of the radiation. In a closed expanding 3-D universe, most of the radiation from a distant bright source at Ze can travel halfway around the universe and be refocused as a "virtual source" at Zv ~1.5 where some of the re-diverging radiation arrives later to our instruments. With the added fourth dimension, the SC-model makes some spectacular predictions for these virtual sources. Indeed, the CBR becomes a re-focused "backside" microwave radiation with its structure amplified in size and decreased in luminosity by a factor ~ 1/350. "Viewed" in the optical from a direction opposite the CBR, the same, but more evolved, structure at "virtual Zsame" would certainly fix the geometry and size of our universe. Virtual sources are also added radiation to the diffuse background of X-rays and infrared. The CBR dipole suggests a preferred reference frame. Reflected light signals in a non-accelerated frame show, in principle, the moving frame could be brought to rest in the comoving frame.

  12. Transport in complex magnetic geometries: 3D modelling of ergodic edge plasmas in fusion experiments

    NASA Astrophysics Data System (ADS)

    Runov, A.; Kasilov, S.; Reiter, D.; McTaggart, N.; Bonnin, X.; Schneider, R.

    2003-03-01

    Both stellarators and tokamaks can have quite complex magnetic topologies in the plasma edge. Special complexity is introduced by ergodic effects producing stochastic domains. Conventional numerical methods from fluid dynamics are not applicable in this case. In the present paper, we discuss two alternative possibilities. Our multiple coordinate system approach (MCSA) [Phys. Plasmas 8 (2001) 916] originally developed for the TEXTOR DED allows modelling of plasma transport in general magnetic field structures. The main idea of the concept is: magnetic field lines can exhibit truly stochastic behavior only for large distances (compared to the Kolmogorov length), while for smaller distances, the field remains regular. Thus, one can divide the computational domain into a finite set of sub-domains, introduce local magnetic coordinate systems in each and use an 'interpolated cell mapping' technique to switch between the neighboring coordinate systems. A 3D plasma fluid code (E3D, based upon MCSA) is applied to realistic geometries. We also introduce here some new details of the algorithm (stellarator option). The results obtained both for intrinsic (stellarator) and external (tokamak with ergodic divertor) perturbations of the magnetic field are discussed. Another approach, also using local coordinate systems, but based on more conventional finite difference methods, is also under development. Here, we present the outline of the algorithm and discuss its potential as compared to the Lagrangian Monte-Carlo approach.

  13. A 3D resistivity model derived from the transient electromagnetic data observed on the Araba fault, Jordan

    NASA Astrophysics Data System (ADS)

    Rödder, A.; Tezkan, B.

    2013-01-01

    72 inloop transient electromagnetic soundings were carried out on two 2 km long profiles perpendicular and two 1 km and two 500 m long profiles parallel to the strike direction of the Araba fault in Jordan which is the southern part of the Dead Sea transform fault indicating the boundary between the African and Arabian continental plates. The distance between the stations was on average 50 m. The late time apparent resistivities derived from the induced voltages show clear differences between the stations located at the eastern and at the western part of the Araba fault. The fault appears as a boundary between the resistive western (ca. 100 ?m) and the conductive eastern part (ca. 10 ?m) of the survey area. On profiles parallel to the strike late time apparent resistivities were almost constant as well in the time dependence as in lateral extension at different stations, indicating a 2D resistivity structure of the investigated area. After having been processed, the data were interpreted by conventional 1D Occam and Marquardt inversion. The study using 2D synthetic model data showed, however, that 1D inversions of stations close to the fault resulted in fictitious layers in the subsurface thus producing large interpretation errors. Therefore, the data were interpreted by a 2D forward resistivity modeling which was then extended to a 3D resistivity model. This 3D model explains satisfactorily the time dependences of the observed transients at nearly all stations.

  14. Subsurface geometry of the San Andreas-Calaveras fault junction: influence of serpentinite and the Coast Range Ophiolite

    USGS Publications Warehouse

    Watt, Janet Tilden; Ponce, David A.; Graymer, Russell W.; Jachens, Robert C.; Simpson, Robert W.

    2014-01-01

    While an enormous amount of research has been focused on trying to understand the geologic history and neotectonics of the San Andreas-Calaveras fault (SAF-CF) junction, fundamental questions concerning fault geometry and mechanisms for slip transfer through the junction remain. We use potential-field, geologic, geodetic, and seismicity data to investigate the 3-D geologic framework of the SAF-CF junction and identify potential slip-transferring structures within the junction. Geophysical evidence suggests that the San Andreas and Calaveras fault zones dip away from each other within the northern portion of the junction, bounding a triangular-shaped wedge of crust in cross section. This wedge changes shape to the south as fault geometries change and fault activity shifts between fault strands, particularly along the Calaveras fault zone (CFZ). Potential-field modeling and relocated seismicity suggest that the Paicines and San Benito strands of the CFZ dip 65° to 70° NE and form the southwest boundary of a folded 1 to 3?km thick tabular body of Coast Range Ophiolite (CRO) within the Vallecitos syncline. We identify and characterize two steeply dipping, seismically active cross structures within the junction that are associated with serpentinite in the subsurface. The architecture of the SAF-CF junction presented in this study may help explain fault-normal motions currently observed in geodetic data and help constrain the seismic hazard. The abundance of serpentinite and related CRO in the subsurface is a significant discovery that not only helps constrain the geometry of structures but may also help explain fault behavior and the tectonic evolution of the SAF-CF junction.

  15. Learning 3D Object Templates by Hierarchical Quantization of Geometry and Appearance Spaces

    E-print Network

    Zhu, Song Chun

    object tem- plates, more specifically, 3D car templates from view la- beled images. The 3D templates car template and its deformed projections on object images. The 3D template is composed of planar part segments and geometric shapes in 3D space. We collected a new car image dataset, where view points are more

  16. Strike-slip fault geometry in Turkey and its influence on earthquake activity

    Microsoft Academic Search

    A. A. Barka; K. Kadinsky-Cade

    1988-01-01

    The geometry of Turkish strike-slip faults is reviewed, showing that fault geometry plays an important role in controlling the location of large earthquake rupture segments along the fault zones. It is found that large earthquake ruptures generally do not propagate past individual stepovers that are wider than 5 km or bends that have angles greater than about 30 degrees. It

  17. Results of 3-D georadar surveying and trenching the San Andreas fault near its northern landward limit

    Microsoft Academic Search

    Alan Green; Ralf Gross; Klaus Holliger; Heinrich Horstmeyer; John Baldwin

    2003-01-01

    As part of a program to determine the location and geometry of the San Andreas Fault (SAF) buried beneath shallow sediments near its northern landward limit, three >20-m-long parallel trenches were constructed at positions distributed over a distance of ?55 m. The majority of excavated material comprised unconsolidated fluvial sediments deposited in a number of paleochannels. Single zones of active

  18. Pore Space Geometry and Seismic Anisotropy of Rocks: 3-D Experimental Investigation

    NASA Astrophysics Data System (ADS)

    Spacek, P.; Melichar, R.; Ulrich, S.

    2004-12-01

    Pressure-driven closing of the pores in the rock sample results in changes of its effective physical properties. We use 3-D ultrasonic pulse-transmission method to characterize the relationships between the spatial distribution of microcracks and elastic anisotropy of the rock. With the use of apparatus developed in Geophysical Institute, Prague, the P-wave velocities and amplitudes ({\\IT VP} and {\\IT AP}) are measured in 132 directions on spherical rock samples. The measurements are carried out at several steps of confining pressure within pressure-increasing and pressure-decreasing paths (0.1-400, 400-0.1 MPa). Then the directions of maximum and minimum velocities and amplitudes are found for which the measurements is repeated under continually changing pressure. As the measurements are repeated at the same position under various pressures, the data can be processed so that the change of the {\\IT VP} and {\\IT AP} between the individual pressure-steps and the hysteresis at particular pressure can be seen directly. The resulting differential diagrams show the magnitude of {\\IT VP} and {\\IT AP} changes in 3-D which are mainly due to the pressure-induced closing of microcracks, and respectively, the flexibility of the microcracks. Using the data measured at high confining pressure or those computed with averaging method we are able to distinguish the influence the deformation-induced lattice re-orientations from the pore-related properties. Numerous measurements carried out on various rock samples show that the anisotropic patterns of {\\IT VP} and {\\IT AP} changes due to the closing of oriented microcracks and other pores highly correlate with the macroscopic structural features of the rock (preferred grain-shape orientation, fracture cleavage, stretching lineation) and are sensitive to them. It is believed that in such cases where the structural features associated with porosity can not be observed directly, the above outlined method will be applicable as a tool for the examination of pore space geometry.

  19. High resolution 3D laser scanner measurements of a strike-slip fault quantify its morphological anisotropy at all scales

    E-print Network

    Renard, Francois; Marsan, Davd; Schmittbuhl, Jean

    2008-01-01

    The surface roughness of a recently exhumed strikeslip fault plane has been measured by three independent 3D portable laser scanners. Digital elevation models of several fault surface areas, from 1 m2 to 600 m2, have been measured at a resolution ranging from 5 mm to 80 mm. Out of plane height fluctuations are described by non-Gaussian distribution with exponential long range tails. Statistical scaling analyses show that the striated fault surface exhibits self-affine scaling invariance with a small but significant directional morphological anisotropy that can be described by two scaling roughness exponents, H1 = 0.7 in the direction of slip and H2 = 0.8 perpendicular to the direction of slip.

  20. Index spaces for 3D retrieval: toward a better understanding of their geometry and distribution

    NASA Astrophysics Data System (ADS)

    Paquet, E.; Viktor, H. L.

    2010-02-01

    Distance is a fundamental concept when considering the information retrieval and cluster analysis of 3D information. That is, a large number of information retrieval descriptor comparison and cluster analysis algorithms are built around the very concept of the distance, such as the Mahalanobis or Manhattan distances, between points. Although not always explicitly stated, a significant proportion of these distances are, by nature, Euclidian. This implies that it is assumed that the data distribution, from a geometrical point of view, may be associated with a Euclidian flat space. In this paper, we draw attention to the fact that this association is, in many situations, not appropriate. Rather, the data should often be characterised by a Riemannian curved space. It is shown how to construct such a curved space and how to analyse its geometry from a topological point of view. The paper also illustrates how, in curved space, the distance between two points may be calculated. In addition, the consequences for information retrieval and cluster analysis algorithms are discussed.

  1. A Study of Static Shift Removal Methods in a 3D Magnetotelluric Survey at Pisagua Fault, Chile.

    NASA Astrophysics Data System (ADS)

    Bascur, J.; Comte, D.; Dias, D.; Siripunvaraporn, W.

    2014-12-01

    The static shift is one of the main problems that cause misleads in the magnetotellurics (MT) interpretation. This work presents a study comparing methods for removing the static shift effect from MT data acquired around the Pisagua Fault in Chile (2014). This evaluation considers the methods based on the joint inversion of the subsurface resistivity with the static shift effect and the calibration based on the TDEM data.First, it was developed a formulation in the data space, following the work of W. Siripunvaraporn (2005), that allows the joint inversion of the resistivity model and the static shift effect. That formulation makes it possible to use any linear representation for removing the static shift in the MT stations. This property permits compare the representation proposed by Sasaki (2004) and the static shift tensor, which use a 2x2 matrix to correct the effect. The last one is suggested to be a better model for 3D MT responses, because it can reproduce the distortion on the phase of MT data.Twenty one stations, measuring MT and TDEM methods, were acquired at the east side of the Pisagua town in the North of Chile (figure). In this place, there is an evident scarp on the topography that reveals the existence of an important fault (Pisagua Fault). Also, the Chilean desert at this location is characterized by the presence of shallow nitrate deposits (called "caliche"), whose have an elevated electrical resistance and can produce the static shift effect in the MT stations. For those reasons it was expected that the sector around the Pisagua Fault was an adequate place to evaluate static correction methods, because the data certainly would be distorted by the static shift and a successful correction method should reveal the fault observed at surface.The MT data acquired have mostly a 3D dimensionality (using A. Marti criteria, 2009) and show signs of being static shifted. A 3D inversion of this data, without considering the static shift, results in a poor misfit and the Pisagua fault does not appear in the model obtained. Calibrating the MT data with the TDEM soundings marginally improve the results. Only the joint inversion methods that include static shift effect could obtain models where the Pisagua fault is present and their responses have an adequate misfit with the data.

  2. Statistical mechanics of the 3D axi-symmetric Euler equations in a Taylor-Couette geometry

    E-print Network

    Paris-Sud XI, Université de

    Statistical mechanics of the 3D axi-symmetric Euler equations in a Taylor-Couette geometry Simon ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 simon.thalabard@cea.fr 1 hal-00829488,version3-16Nov2013 #12;3 Statistical mechanics-symmetric microcanonical ensemble . . . 10 3.2 Statistical mechanics of the toroidal field

  3. Folded Paper Geometry from 2D Pattern and 3D Contour Damien Rohmer1,2,3

    E-print Network

    Paris-Sud XI, Université de

    -like surfaces, not re- stricted to the convex hull of their contour points and where folds are automaticallyFolded Paper Geometry from 2D Pattern and 3D Contour Damien Rohmer1,2,3 , Marie-Paule Cani1University of Lyon, CPE Lyon. Abstract Folded paper exhibits very characteristic shapes, due to the presence

  4. From 3D Scene Geometry to Human Workspace Abhinav Gupta, Scott Satkin, Alexei A. Efros and Martial Hebert

    E-print Network

    Gordon, Geoffrey J.

    ,ssatkin,efros,hebert}@ri.cmu.edu Abstract We present a human-centric paradigm for scene under- standing. Our approach goes beyond estimating-driven vocabulary of human inter- actions. Our method builds upon the recent work in indoor scene understandingFrom 3D Scene Geometry to Human Workspace Abhinav Gupta, Scott Satkin, Alexei A. Efros and Martial

  5. Model-based Approach to Automatic 3D Seismic Horizon Correlation across Faults

    Microsoft Academic Search

    Fitsum Admasu; Klaus D. Tönnies

    2004-01-01

    Seismic data provide detailed information about subsurface structures. Reflection events visible in the seismic data are known as horizons, and indicate boundaries be- tween different rock layers. A fault is a surface along which one side of rock layers has moved relative to the other in a direction parallel to the surface. Faults are recognized in seismic data by discontinuities

  6. A 3D Magnetotelluric Study of the Dead Sea Transform Fault in Jordan

    Microsoft Academic Search

    O. Ritter; J. Schmidt; U. Weckmann; H. Thoss; A. Abueladas; V. Haak

    2001-01-01

    In two experiments in 2000 and 2001, we recorded magnetotelluric data at 138 sites across the Dead Sea Transform Fault (Arava Fault) in Jordan. The sites are distributed along 10 profiles, covering an area of 10 square kilometres. 2D inversion results of the magnetotelluric data and the induction vectors indicate very clearly that the DST is associated with a strong

  7. Magnetic fabric and 3D geometry of the Hombreiro-Sta. Eulaliapluton: Implications for the Variscan structures of eastern Galicia, NW Spain

    NASA Astrophysics Data System (ADS)

    Aranguren, A.

    1997-05-01

    In this paper the internal structure and 3D geometry of the Hombreiro-Sta. Eulalia granitic pluton (Hercynian belt, NWSpain) are described. Characterization of the internal structure was performed from surface data, based on microstructural analysis and anisotropy of magnetic susceptibility studies. The geometrical features of the pluton morphology at depth were derived from gravity data. The pluton is made up of paramagnetic granites and leucogranites (K values ranging between 1.1 and 13.3 × 10-5 SI), with well developed magnetic fabrics (anisotropy degree P? ? 1.05 for 78% of the sampling localities). The results obtained enable us to depict a flat-lying magnetic structure with associated N120°E-trending magnetic lineations. The gravity survey corroborates the subhorizontal laminar geometry of the pluton, which has an estimated thickness of 2 km and an almost planar floor. The 3D morphology is elongate at depth parallel to the linear internal fabric. This would imply that magma emplacement took place along this preferential direction. Whereas the deepest zones of the pluton trend WNW-ESE (elongate parallel to regional ? 1) it is almost rootless. We present data showing that the Hombreiro-Sta. Eulalia pluton emplacement was closely related (spatially and chronologically), along with other granitoid plutons from the Lugo Dome, with two major structures of eastern Galicia: the basal shear zone of the Mondoñedo nappe and the extensional Vivero fault.

  8. Gothic Churches in Paris ST Gervais et ST Protais Image Matching 3d Reconstruction to Understand the Vaults System Geometry

    NASA Astrophysics Data System (ADS)

    Capone, M.; Campi, M.; Catuogno, R.

    2015-02-01

    This paper is part of a research about ribbed vaults systems in French Gothic Cathedrals. Our goal is to compare some different gothic cathedrals to understand the complex geometry of the ribbed vaults. The survey isn't the main objective but it is the way to verify the theoretical hypotheses about geometric configuration of the flamboyant churches in Paris. The survey method's choice generally depends on the goal; in this case we had to study many churches in a short time, so we chose 3D reconstruction method based on image dense stereo matching. This method allowed us to obtain the necessary information to our study without bringing special equipment, such as the laser scanner. The goal of this paper is to test image matching 3D reconstruction method in relation to some particular study cases and to show the benefits and the troubles. From a methodological point of view this is our workflow: - theoretical study about geometrical configuration of rib vault systems; - 3D model based on theoretical hypothesis about geometric definition of the vaults' form; - 3D model based on image matching 3D reconstruction methods; - comparison between 3D theoretical model and 3D model based on image matching;

  9. The Akaso field, Nigeria: Use of integrated 3-D seismic/fault slicing/clay shearing on fault trapping and dynamic leakage

    SciTech Connect

    Jev, B.I.; Kaars-Sijpestein, C.H.; Wilkie, J.T. (Shell Petroleum Development Co. Ltd., Lagos (Nigeria)); Peters, M.P.M.A. (Kon. Shell E and P Lab., Rijswijk (Netherlands))

    1991-03-01

    The Akaso field on the Eastern Niger delta (STOIIP 401 MMstb) is separated from the large Cawthorne Channel field (STOIIP 1307 MMstb) by a major antithetic fault. In 1989 3-D seismic data revealed a subtle back-split off this antithetic to the west of the main Akaso field, behind which stacked amplitude anomalies occurred extending to the tip line of the back-split. Fault slicing and clay smear studies of the back-split and main antithetic indicated strong seal potential with occasional leak windows. These results were fully confirmed by a deviated appraisal well in late 1989 that found 183 MMstb STOIIP in a series of stacked footwall closures. The trapping potential of this fault can be contrasted with its behavior during depletion based upon RFT data acquired in a series of Akaso development wells in 1990. Depletion of the Akaso E and G sands was observed due to production from the juxtaposed C-D and E sands of Cawthorne Channel and subsequent fault breakdown. Dynamic pressure drops of 120 psi and 311 psi observed in the Akaso field therefore represent a prime example of the trapping potential of clay-smeared faults and their subsequent leakage during differential depletion.

  10. High precision Differential Earthquake Location in 3D models: Evidence for a rheological barrier controlling the microseismicity at the Irpinia fault zone in southern Apennines

    NASA Astrophysics Data System (ADS)

    De Landro, Grazia; Amoroso, Ortensia; Alfredo Stabile, Tony; Matrullo, Emanuela; Lomax, Anthony; Zollo, Aldo

    2015-04-01

    A non-linear, global-search, probabilistic, double-difference earthquake location technique is illustrated. The main advantages of this method are the determination of comprehensive and complete solutions through the probability density function (PDF), the use of differential arrival-times as data, and the possibility to use a 3D velocity model both for absolute and relative locations, essential to obtain accurate differentials locations in structurally complex geological media. The joint use of this methodology and an accurate differential times data-set allowed us to carry out an high-resolution, earthquake location analysis, which helped to characterize the active fault geometries in the studied region. We investigated the recent micro-seismicity occurring at the Campanian-Lucanian Apennines, in the crustal volume embedding the fault system which generated the 1980, M 6.9 earthquake in Irpinia. In order to obtain highly accurate seismicity locations we applied the method to the P and S arrival time data set from 1312 events (M<3) that occurred from August 2005 to April 2011, and used the 3D P- and S-wave velocity models, optimized for the area under study. Both catalogue and cross-correlation first arrival-times have been used. The refined seismicity locations show that the events occur in a volume delimited by the faults activated during the 1980 Irpinia M 6.9 earthquake on sub-parallel, predominantly normal faults. Corresponding to a contact zone between different rheology rock formations (carbonate platform and basin residuals), we evidence an abrupt interruption of the seismicity across a SW-NE oriented structural discontinuity. This "barrier" appears to be located in the area bounded by the fault segments activated during the first (0 sec) and the second (20 sec) rupture episodes of the 80's Irpinia earthquake. We hypothesize that this geometrical barrier can have played a key role during the 1980 Irpinia event, and possibly controlled the delayed times of activation of the two rupture segments.

  11. Development and application of a 3-D geometry/mass model for LDEF satellite ionizing radiation assessments

    NASA Technical Reports Server (NTRS)

    Colborn, B. L.; Armstrong, T. W.

    1992-01-01

    A computer model of the three dimensional geometry and material distributions for the LDEF spacecraft, experiment trays, and, for selected trays, the components of experiments within a tray was developed for use in ionizing radiation assessments. The model is being applied to provide 3-D shielding distributions around radiation dosimeters to aid in data interpretation, particularly in assessing the directional properties of the radiation exposure. Also, the model has been interfaced with radiation transport codes for 3-D dosimetry response predictions and for calculations related to determining the accuracy of trapped proton and cosmic ray environment models. The methodology is described used in developing the 3-D LDEF model and the level of detail incorporated. Currently, the trays modeled in detail are F2, F8, and H12 and H3. Applications of the model which are discussed include the 3-D shielding distributions around various dosimeters, the influence of shielding on dosimetry responses, and comparisons of dose predictions based on the present 3-D model vs those from 1-D geometry model approximations used in initial estimates.

  12. Kinematic Analysis of Normal Faults from 3D Seismics within the Otway Basin, Australia: Evidence for Oblique Movement in a Passive Margin

    NASA Astrophysics Data System (ADS)

    Tanner, D. C.; Ziesch, J.; Beilecke, T.; Krawczyk, C. M.

    2014-12-01

    The onshore Otway Basin is dominated by normal faults and only minimal strike-slip faulting has been reported. The basin is part of the NW-striking, passive margin that records the break-up of Gondwana and the Antarctic-Australian separation between Late Jurassic and Miocene times. From a 3D seismic cube (ca. 8 km x 7 km x 4 km depth) around the CO2CRC Otway site in SE Australia, we interpreted eight major, Cretaceous and Tertiary stratigraphic horizons (all syn-rift) and over 24 major normal faults. Detailed analysis of the fault system in our 3D geological model shows that the area is characterised by southwest-dipping, normal faults that have a listric character in the SW and planar character in the NE. North-dipping, antithetic faults developed secondarily due to movement on the major faults. Syn-sedimentary movement caused fourfold strata thicknesses in the hanging-wall of the faults. Fault offset increases towards the south; up to 800 m in the lower stratigraphy. Most faults, however, die out before the Eocene. Using different techniques we determined that 60% the major faults didn't move in a pure dip-slip fashion, rather the movement contained a component of dextral strike-slip. In particular, juxtaposition maps of the stratigraphic horizons on the fault surfaces shows that in the obliquely-displaced faults the tip-lines of the faults are extremely asymmetric, with one flatly-dipping tip-line and one steep, overturned tip-line. Dip-slip faults demonstrate symmetrical convergence of the tip-lines. However faults with different kinematics are not grouped, but heterogeneously distributed over the model, suggesting strain-partitioning took place. This evidences that faults react differently when the stress field in the passive margin changes direction, but in a way that suggests that they are interacting.

  13. The Carboneras Fault Zone (SE Spain): Constraints on Fault Zone Properties and Geometry from Controlled-Source-Generated Guided Seismic Waves

    NASA Astrophysics Data System (ADS)

    Rietbrock, A.; Haberland, C. A.; Faulkner, D. R.; Nippress, S.; Rutter, E. H.; Kelly, C. M.; Teixido, T.

    2014-12-01

    We combine geophysical data, field-geological mapping and lab measurements to study the Carboneras fault zone (CFZ) in SE Spain. The CFZ is part of the Trans-Alborán Shear Zone which constitutes part of the diffuse plate boundary between Africa and Iberia. The CFZ is inferred to behave as a stretching transform fault with˜40 km left-lateral offset. It was active principally between 12 - 6 Ma BP, and has been exhumed from ca. 1 - 2 km depth. The relatively recent movement history and the semi-arid terrain lead to excellent exposure.The phyllosilicate-rich fault gougeis excellently preserved. In 2010 we conducted a controlled source seismic experiment at the CFZ in which explosive sources in boreholes (two groups of 3 explosions) were placed in two strands of the fault zone. The signals were observed with dense linear seismic arrays crossing the CFZ at 3.5km and 8.3km distance, respectively. The recordings show clear high-energy P-phases at receivers and from sources located at or near the fault zone. We interpret these phases as P-waves trapped in the low-velocity layer (waveguide) formed by the damage zone of the fault(s). With waveform modeling (using an analytical solution assuming a straight waveguide embedded in two quarter spaces and a line source at depth) we derive basic models well-explaining the observations. Lab-measurements of the different rocks constrain the possible models. Additionally, we employed extensive three-dimensional finite-difference (3D-FD) modeling with more realistic (curved and anastomosing) waveguide geometries. It seems that the studied segments of the CFZ form effective waveguides for seismic waves with connectivity over several kilometers. The derived seismic models together with lab measurements of the seismic velocities indicate that the average fault zone core widths are in the order of 15 to 25m which is in good agreement with surface geological mapping.

  14. Three-Dimensional Splay Fault Geometry and Implications for Tsunami Generation

    Microsoft Academic Search

    G. F. Moore; N. L. Bangs; A. Taira; S. Kuramoto; E. Pangborn; H. J. Tobin

    2007-01-01

    Megasplay faults, very long thrust faults that rise from the subduction plate boundary megathrust and intersect the sea floor at the landward edge of the accretionary prism, are thought to play a role in tsunami genesis. We imaged a megasplay thrust system along the Nankai Trough in three dimensions, which allowed us to map the splay fault geometry and its

  15. Geometry and scaling relations of a population of very small rift-related normal faults

    E-print Network

    Geometry and scaling relations of a population of very small rift-related normal faults Roy W normal faults within the Solite Quarry of the Dan River rift basin range in length from a few millimetres to a few metres and are possibly the smallest visible faults studied to date. Displacement is greatest

  16. Stratigraphic architecture and fault offsets of alluvial terraces at Te Marua, Wellington fault, New Zealand, revealed by pseudo-3D GPR investigation

    NASA Astrophysics Data System (ADS)

    Beauprêtre, S.; Manighetti, I.; Garambois, S.; Malavieille, J.; Dominguez, S.

    2013-08-01

    earthquake slips on faults are commonly determined by measuring morphological offsets at current ground surface. Because those offsets might not always be well preserved, we examine whether the first 10 m below ground surface contains relevant information to complement them. We focus on the Te Marua site, New Zealand, where 11 alluvial terraces have been dextrally offset by the Wellington fault. We investigated the site using pseudo-3D Ground Penetrating Radar and also produced a high-resolution digital elevation model (DEM) of the zone to constrain the surface slip record. The GPR data reveal additional information: (1) they image the 3D stratigraphic architecture of the seven youngest terraces and show that they are strath terraces carved into graywacke bedrock. Each strath surface is overlain by 3-5 m of horizontally bedded gravel sheets, including two pronounced and traceable reflectors; (2) thanks to the multilayer architecture, terrace risers and channels are imaged at three depths and their lateral offsets can be measured three to four times, constraining respective offsets and their uncertainties more reliably; and (3) the offsets are better preserved in the subsurface than at the ground surface, likely due to subsequent erosion-deposition on the latter. From surface and subsurface data, we infer that Te Marua has recorded six cumulative offsets of 2.9, 7.6, 18, 23.2, 26, and 31 m (± 1-2 m). Large earthquakes on southern Wellington fault might produce 3-5 m of slip, slightly less than previously proposed. Pseudo-3D GPR thus provides a novel paleoseismological tool to complement and refine surface investigations.

  17. Accuracy Evaluation of 3D Geometry from Low-Attitude UAV collections A case at Zijin Mine

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Wu, L.; Chen, S.; Shu, D.; Xu, Z.; Li, F.; Wang, R.

    2014-04-01

    This study investigates the usability of low-attitude unmanned aerial vehicle (UAV) acquiring high resolution images for the geometry reconstruction of opencast mine. Image modelling techniques like Structure from Motion (SfM) and Patch-based Multiview Stereo (PMVS) algorithms are used to generate dense 3D point cloud from UAV collections. Then, precision of 3D point cloud will be first evaluated based on Real-time Kinematic (RTK) ground control points (GCPs) at point level. The experimental result shows that the mean square error of the UAV point cloud is 0.11 m. Digital surface model (DSM) of the study area is generated from UAV point cloud, and compared with that from the Terrestrial Laser Scanner (TLS) data for further comparison at the surface level. Discrepancy map of 3D distances based on DSMs shows that most deviation is less than ±0.4 m and the relative error of the volume is 1.55 %.

  18. The differences in the development of Rayleigh-Taylor instability in 2D and 3D geometries

    NASA Astrophysics Data System (ADS)

    Kuchugov, P. A.; Rozanov, V. B.; Zmitrenko, N. V.

    2014-06-01

    Results are presented from theoretical analysis and numerical simulations aimed to clarify specific features of Rayleigh-Taylor instability in 2D and 3D geometries. Two series of simulations, one with an isolated single-mode perturbation of the interface and the other with a random density perturbation, were performed. It is shown that the relative evolutions of integral characteristics for the first and the second series are different in 2D and 3D geometries. An attempt is made to interpret this result in the framework of the previously developed evolutionary approach based on the concept of the "critical age" of the perturbation (where, by the age is meant the product of the wavenumber and amplitude). The critical age corresponds to the destruction of the main mushroom-like structure formed during the development of Rayleigh-Taylor instability due to the onset of the secondary Kelvin-Helmholtz instability.

  19. Automatic Method for Correlating Horizons across Faults in 3D Seismic Data

    Microsoft Academic Search

    Fitsum Admasu; Klaus D. Tönnies

    2004-01-01

    Horizons are visible boundaries between certain sediment layers in seismic data, and a fault is a crack of horizons and it is recognized in seismic data by the discontinuities of horizons layers. Interpretation of seismic data is a time- consuming manual task, which is only partially supported by computer methods. In this paper, we present an auto- matic method for

  20. Anisotropic 3D seismic features for robust horizons correlation across faults

    Microsoft Academic Search

    Fitsum Admasu; Klaus D. Tönnies

    2005-01-01

    While 3D seismic data become widespread and the data-sets get larger, the demand for automation to speed up the seismic interpretation process is increasing as well. However, the development of intelligent tools which can do more to assist interpreters has been difficult due to low information content in seismic data. In this paper, we present an image processing method in

  1. Geometry and kinematics of adhesive wear in brittle strike-slip fault zones

    Microsoft Academic Search

    Mark T. Swanson

    2005-01-01

    Detailed outcrop surface mapping in Late Paleozoic cataclastic strike-slip faults of coastal Maine shows that asymmetric sidewall ripouts, 0.1 200 m in length, are a significant component of many mapped faults and an important wall rock deformation mechanism during faulting. The geometry of these structures ranges from simple lenses to elongate slabs cut out of the sidewalls of strike-slip faults

  2. Geometry and kinematics of adhesive wear in brittle strike-slip fault zones

    Microsoft Academic Search

    Mark T. Swanson

    2005-01-01

    Detailed outcrop surface mapping in Late Paleozoic cataclastic strike-slip faults of coastal Maine shows that asymmetric sidewall ripouts, 0.1–200m in length, are a significant component of many mapped faults and an important wall rock deformation mechanism during faulting. The geometry of these structures ranges from simple lenses to elongate slabs cut out of the sidewalls of strike-slip faults by a

  3. Preliminary Pseudo 3-D Imagery of the State Line Fault, Stewart Valley, Nevada Using Seismic Reflection Data

    Microsoft Academic Search

    S. C. Saldaña; C. M. Snelson; W. J. Taylor; M. Beachly; C. M. Cox; R. Davis; M. Stropky; R. Phillips; C. Robins; C. Cothrun

    2007-01-01

    The Pahrump Fault system is located in the central Basin and Range region and consists of three main fault zones: the Nopah range front fault zone, the State Line fault zone and the Spring Mountains range fault zone. The State Line fault zone is made up north-west trending dextral strike-slip faults that run parallel to the Nevada- California border. Previous

  4. The Role of Faulting on the Growth of a Carbonate Platform: Evidence from 3D Seismic Analysis and Section Restoration

    NASA Astrophysics Data System (ADS)

    Nur Fathiyah Jamaludin, Siti; Pubellier, Manuel; Prasad Ghosh, Deva; Menier, David; Pierson, Bernard

    2014-05-01

    Tectonics in addition to other environmental factors impacts the growth of carbonate platforms and plays an important role in shaping the internal architecture of the platforms. Detailed of faults and fractures development and healing in carbonate environment have not been explored sufficiently. Using 3D seismic and well data, we attempt to reconstruct the structural evolution of a Miocene carbonate platform in Central Luconia Province, offshore Malaysia. Luconia Province is located in the NW coast of Borneo and has become one of the largest carbonate factories in SE Asia. Seismic interpretations including seismic attribute analysis are applied to the carbonate platform to discern its sedimentology and structural details. Detailed seismic interpretations highlight the relationships of carbonate deposition with syn-depositional faulting. Branching conjugate faults are common in this carbonate platform and have become a template for reef growth, attesting lateral facies changes within the carbonate environments. Structural restoration was then appropriately performed on the interpreted seismic sections based on sequential restoration techniques, and provided images different from those of horizon flattening methods. This permits us to compensate faults' displacement, remove recent sediment layers and finally restore the older rock units prior to the fault motions. It allows prediction of platform evolution as a response to faulting before and after carbonate deposition and also enhances the pitfalls of interpretation. Once updated, the reconstructions allow unravelling of the un-seen geological features underneath the carbonate platform, such as paleo-structures and paleo-topography which in turn reflects the paleo-environment before deformations took place. Interestingly, sections balancing and restoration revealed the late-phase (Late Oligocene-Early Miocene) rifting of South China Sea, otherwise difficult to visualize on seismic sections. Later it is shown that this carbonate platform was possibly originated from two or more connected reef build-ups. The platform evolution in terms of tectonic influences on carbonate growth and development may serve as a case example for re-evaluation of pre-Late Miocene structures as a new potential target for hydrocarbon exploration in Central Luconia Province. Eventually, techniques used in this study might be of interest to oil and gas explorers in carbonate system.

  5. Geometry of crustal faults: implications for seismicity distributions

    NASA Astrophysics Data System (ADS)

    Kaven, J. O.; Pollard, D. D.

    2009-12-01

    We investigate the importance of geometric complexity in fault systems using relocated seismicity from a catalog of events for the Joshua Tree - Landers earthquake sequence. The spatial density of seismicity is used to locate finite width fault zones and construct surfaces indicative of the centers of these fault zones. The method indentifies ten separate faults ranging in average strike from north-south to east-west that compare well with surface fault maps. These faults exhibit significant surface curvature with the Joshua Tree fault departing from a planar approximation by more than 2000m. The mechanical effects of the geometrically complex fault surfaces are illustrated using solutions to the quasi-static boundary value problem and investigating the resultant stresses and tractions induced by slip on the Joshua Tree fault before the rupture of the Landers earthquake. We find that the propensity for slip on the Landers faults increased in regions of initiation and largest slip during the subsequent event. The geometrically complex models predict greater propensity to slip along the northern faults involved in the Landers earthquake than the commonly used planar and vertical four-fault models. The stresses adjacent to the Joshua Tree fault are investigated by calculating the changes in Coulomb stresses on optimally oriented surfaces of weakness. We find that the geometrically complex model for Joshua Tree fault predicts the aftershocks immediately following the Joshua Tree earthquake quite well, and better than the planar fault model.

  6. Geometry and kinematics of adhesive wear in brittle strike-slip fault zones

    NASA Astrophysics Data System (ADS)

    Swanson, Mark T.

    2005-05-01

    Detailed outcrop surface mapping in Late Paleozoic cataclastic strike-slip faults of coastal Maine shows that asymmetric sidewall ripouts, 0.1-200 m in length, are a significant component of many mapped faults and an important wall rock deformation mechanism during faulting. The geometry of these structures ranges from simple lenses to elongate slabs cut out of the sidewalls of strike-slip faults by a lateral jump of the active zone of slip during adhesion along a section of the main fault. The new irregular trace of the active fault after this jump creates an indenting asperity that is forced to plow through the adjoining wall rock during continued adhesion or be cut off by renewed motion along the main section of the fault. Ripout translation during adhesion sets up the structural asymmetry with trailing extensional and leading contractional ends to the ripout block. The inactive section of the main fault trace at the trailing end can develop a 'sag' or 'half-graben' type geometry due to block movement along the scallop-shaped connecting ramp to the flanking ripout fault. Leading contractional ramps can develop 'thrust' type imbrication and forces the 'humpback' geometry to the ripout slab due to distortion of the inactive main fault surface by ripout translation. Similar asymmetric ripout geometries are recognized in many other major crustal scale strike-slip fault zones worldwide. Ripout structures in the 5-500 km length range can be found on the Atacama fault system of northern Chile, the Qujiang and Xiaojiang fault zones in western China, the Yalakom-Hozameen fault zone in British Columbia and the San Andreas fault system in southern California. For active crustal-scale faults the surface expression of ripout translation includes a coupled system of extensional trailing ramps as normal oblique-slip faults with pull-apart basin sedimentation and contractional leading ramps as oblique thrust or high angle reverse faults with associated uplift and erosion. The sidewall ripout model, as a mechanism for adhesive wear during fault zone deformation, can be useful in studies of fault zone geometry, kinematics and evolution from outcrop- to crustal-scales.

  7. Geodetic slip rates in the southern San Andreas Fault system: Effects of elastic heterogeneity and fault geometry

    NASA Astrophysics Data System (ADS)

    Lindsey, E. O.; Fialko, Y.

    2013-02-01

    We use high resolution interferometric synthetic aperture radar and GPS measurements of crustal motion across the southern San Andreas Fault system to investigate the effects of elastic heterogeneity and fault geometry on inferred slip rates and locking depths. Geodetically measured strain rates are asymmetric with respect to the mapped traces of both the southern San Andreas and San Jacinto faults. Two possibilities have been proposed to explain this observation: large contrasts in crustal rigidity across the faults, or an alternate fault geometry such as a dipping San Andreas fault or a blind segment of the San Jacinto Fault. We evaluate these possibilities using a two-dimensional elastic model accounting for heterogeneous structure computed from the Southern California Earthquake Center crustal velocity model CVM-H 6.3. The results demonstrate that moderate variations in elastic properties of the crust do not produce a significant strain rate asymmetry and have only a minor effect on the inferred slip rates. However, we find that small changes in the location of faults at depth can strongly impact the results. Our preferred model includes a San Andreas Fault dipping northeast at 60°, and two active branches of the San Jacinto fault zone. In this case, we infer nearly equal slip rates of 18 ± 1 and 19 ± 2 mm/yr for the San Andreas and San Jacinto fault zones, respectively. These values are in good agreement with geologic measurements representing average slip rates over the last 104-106 years, implying steady long-term motion on these faults.

  8. Fault strength in Marmara region inferred from the geometry of the principle stress axes and fault orientations: A case study for the Prince's Islands fault segment

    NASA Astrophysics Data System (ADS)

    Pinar, Ali; Coskun, Zeynep; Mert, Aydin; Kalafat, Dogan

    2015-04-01

    The general consensus based on historical earthquake data point out that the last major moment release on the Prince's islands fault was in 1766 which in turn signals an increased seismic risk for Istanbul Metropolitan area considering the fact that most of the 20 mm/yr GPS derived slip rate for the region is accommodated mostly by that fault segment. The orientation of the Prince's islands fault segment overlaps with the NW-SE direction of the maximum principle stress axis derived from the focal mechanism solutions of the large and moderate sized earthquakes occurred in the Marmara region. As such, the NW-SE trending fault segment translates the motion between the two E-W trending branches of the North Anatolian fault zone; one extending from the Gulf of Izmit towards Ç?narc?k basin and the other extending between offshore Bak?rköy and Silivri. The basic relation between the orientation of the maximum and minimum principal stress axes, the shear and normal stresses, and the orientation of a fault provides clue on the strength of a fault, i.e., its frictional coefficient. Here, the angle between the fault normal and maximum compressive stress axis is a key parameter where fault normal and fault parallel maximum compressive stress might be a necessary and sufficient condition for a creeping event. That relation also implies that when the trend of the sigma-1 axis is close to the strike of the fault the shear stress acting on the fault plane approaches zero. On the other hand, the ratio between the shear and normal stresses acting on a fault plane is proportional to the coefficient of frictional coefficient of the fault. Accordingly, the geometry between the Prince's islands fault segment and a maximum principal stress axis matches a weak fault model. In the frame of the presentation we analyze seismological data acquired in Marmara region and interpret the results in conjuction with the above mentioned weak fault model.

  9. Effects of Training Method and Gender on Learning 2D/3D Geometry

    ERIC Educational Resources Information Center

    Khairulanuar, Samsudin; Nazre, Abd Rashid; Jamilah, H.; Sairabanu, Omar Khan; Norasikin, Fabil

    2010-01-01

    This article reports the findings of an experimental study involving 36 primary school students (16 girls, 20 boys, Mean age = 9.5 years, age range: 8-10 years) in geometrical understanding of 2D and 3D objects. Students were assigned into two experimental groups and one control group based on a stratified random sampling procedure. The first…

  10. 3D Brain surface matching based on geodesics and local geometry

    Microsoft Academic Search

    Yongmei Michelle Wang; Bradley S. Peterson; Lawrence H. Staib

    2003-01-01

    The non-rigid registration of surfaces is a complex and difficult task for which there are many important applications, such as comparing shape between deformable objects and com- paring associated function. This paper presents a new approach for brain surface matching by determining the correspondence of 3D point sets between pairs of surfaces. The algorithm is based on shape using a

  11. Index spaces for 3D retrieval: toward a better understanding of their geometry and distribution

    Microsoft Academic Search

    E. Paquet; H. L. Viktor

    2010-01-01

    Distance is a fundamental concept when considering the information retrieval and cluster analysis of 3D information. That is, a large number of information retrieval descriptor comparison and cluster analysis algorithms are built around the very concept of the distance, such as the Mahalanobis or Manhattan distances, between points. Although not always explicitly stated, a significant proportion of these distances are,

  12. Deformation of Rock Mass Caused by Strike-Slip Faulting: 3D Analysis of Analogue Models by Helical X-ray Computed Tomography

    Microsoft Academic Search

    K. Ueta

    2007-01-01

    Strike-slip fault zones are induced experimentally in artificial rock subjected to strike-slip displacement along basement fault. The purpose is to investigate in three dimensions, the geometries and sequence of development of structural elements comprising the fault zones by use of a helical X-ray CT scanner. 860 mm long, 310 mm wide, 25 mm high artificial rocks were made by mixing

  13. Accurate 3D reconstruction of complex blood vessel geometries from intravascular ultrasound

    E-print Network

    Subramanian, Kalpathi R.

    structures. The two geometries studied are a bovine artery vascular graft having U-shape and a constriction wall, is commonly used in visualizing the vascular lumen, atherosclerotic plaque and other structures

  14. Insights into the 3D architecture of an active caldera ring-fault at Tendürek volcano through modeling of geodetic data

    NASA Astrophysics Data System (ADS)

    Bathke, H.; Nikkhoo, M.; Holohan, E. P.; Walter, T. R.

    2015-07-01

    The three-dimensional assessment of ring-fault geometries and kinematics at active caldera volcanoes is typically limited by sparse field, geodetic or seismological data, or by only partial ring-fault rupture or slip. Here we use a novel combination of spatially dense InSAR time-series data, numerical models and sand-box experiments to determine the three-dimensional geometry and kinematics of a sub-surface ring-fault at Tendürek volcano in Turkey. The InSAR data reveal that the area within the ring-fault not only subsides, but also shows substantial westward-directed lateral movement. The models and experiments explain this as a consequence of a 'sliding-trapdoor' ring-fault architecture that is mostly composed of outward-inclined reverse segments, most markedly so on the volcano's western flanks but includes inward-inclined normal segments on its eastern flanks. Furthermore, the model ring-fault exhibits dextral and sinistral strike-slip components that are roughly bilaterally distributed onto its northern and southern segments, respectively. Our more complex numerical model describes the deformation at Tendürek better than an analytical solution for a single rectangular dislocation in a half-space. Comparison to ring-faults defined at Glen Coe, Fernandina and Bárðarbunga calderas suggests that 'sliding-trapdoor' ring-fault geometries may be common in nature and should therefore be considered in geological and geophysical interpretations of ring-faults at different scales worldwide.

  15. The Monte Carlo SRNA-VOX code for 3D proton dose distribution in voxelized geometry using CT data.

    PubMed

    Ili?, Radovan D; Spasi?-Joki?, Vesna; Belicev, Petar; Dragovi?, Milos

    2005-03-01

    This paper describes the application of the SRNA Monte Carlo package for proton transport simulations in complex geometry and different material compositions. The SRNA package was developed for 3D dose distribution calculation in proton therapy and dosimetry and it was based on the theory of multiple scattering. The decay of proton induced compound nuclei was simulated by the Russian MSDM model and our own using ICRU 63 data. The developed package consists of two codes: the SRNA-2KG, which simulates proton transport in combinatorial geometry and the SRNA-VOX, which uses the voxelized geometry using the CT data and conversion of the Hounsfield's data to tissue elemental composition. Transition probabilities for both codes are prepared by the SRNADAT code. The simulation of the proton beam characterization by multi-layer Faraday cup, spatial distribution of positron emitters obtained by the SRNA-2KG code and intercomparison of computational codes in radiation dosimetry, indicate immediate application of the Monte Carlo techniques in clinical practice. In this paper, we briefly present the physical model implemented in the SRNA package, the ISTAR proton dose planning software, as well as the results of the numerical experiments with proton beams to obtain 3D dose distribution in the eye and breast tumour. PMID:15798273

  16. Flow properties along field lines in a 3-D tilted-dipole geometry

    Microsoft Academic Search

    V. J. Pizzo

    1995-01-01

    A 3-D MHD simulation of a global, tilted-dipole solar wind flow pattern is analyzed to determine flow properties along individual magnetic field lines. In the model, flow conditions near the Sun are chosen to provide a reasonable match to the interplanetary configuration prevailing during the recent south polar passage by Ulysses, i.e., a streamer belt inclined approximately 30 deg to

  17. 3D Microstructural Investigation of Experimentally Deformed Smectite-rich San Andreas Fault Gouge from the Southern Deforming Zone (SAFOD)

    NASA Astrophysics Data System (ADS)

    Wojatschke, J.; Scuderi, M.; Warr, L. N.; Saffer, D. M.; Marone, C.

    2014-12-01

    Smectite clays have been recognized to play an important role in fault zone strength and slip behavior. Due to their interaction with fluids, hydrological properties change and lead to a weakening of the fault. Some of the weakest clay gouge has been recovered from SAFOD core along the active Central Deforming Zone of the San Andreas Fault, with a coefficient of friction as low as µ=0.095. We conducted laboratory shearing experiments to investigate the microstructural fabric development and frictional behavior of powders and natural intact fault gouge to characterize differences in mechanical and hydrological properties caused by varying smectite clay fabrics. In this study we used almost pure clay powder from SAF gouge (<63 µm) and mixed it with varying amounts of quartz or SAF clasts (120-500 µm). We sheared gouge layers in a double-direct shear configuration housed in a pressure vessel, at an effective normal stress of ?'n = 5 MPa and under saturated conditions with a pore pressure of 2 MPa. We used a relatively low normal stress to allow recovery of material after the experiments for microstructural investigation. We sheared the layers at a constant velocity of 10 ?m/s, followed by a series of slide-hold-slide tests to characterize frictional properties. After the experiments all samples were analyzed using a focused ion beam - scanning electron microscope (FIB-SEM) in order to reconstruct the 3D microstructures associated with experimentally induced polished slip surfaces at the micro- to nanometer scale. Initial results document clear stages of clay fabric development related to the clay to clast ratio, which exhibit similarities with naturally developed fabrics. In smectite-dominated mixtures, principle slip surfaces develop parallel to each other, but these features are modified as the clast content increases. With higher clay content strain hardening becomes more prominent. Clay minerals and fabric developed during shear have a strong effect on gouge mechanical and hydrological properties, and therefore likely play a key role in controlling fault gouge slip behavior at seismogenic depth.

  18. Mesoscopic hydrogel molding to control the 3D geometry of bioartificial muscle tissues

    PubMed Central

    Bian, Weining; Liau, Brian; Badie, Nima

    2010-01-01

    This protocol describes a cell/hydrogel molding method for precise and reproducible biomimetic fabrication of three-dimensional (3D) muscle tissue architectures in vitro. Using a high aspect ratio soft lithography technique, we fabricate polydimethylsiloxane (PDMS) molds containing arrays of mesoscopic posts with defined size, elongation and spacing. On cell/hydrogel molding, these posts serve to enhance the diffusion of nutrients to cells by introducing elliptical pores in the cell-laden hydrogels and to guide local 3D cell alignment by governing the spatial pattern of mechanical tension. Instead of ultraviolet or chemical cross-linking, this method utilizes natural hydrogel polymerization and topographically constrained cell-mediated gel compaction to create the desired 3D tissue structures. We apply this method to fabricate several square centimeter large, few hundred micron-thick bioartificial muscle tissues composed of viable, dense, uniformly aligned and highly differentiated cardiac or skeletal muscle fibers. The protocol takes 4–5 d to fabricate PDMS molds followed by 2 weeks of cell culture. PMID:19798085

  19. Computerized X-ray tomography analysis of three-dimensional fault geometries in basement-induced wrench faulting

    Microsoft Academic Search

    K. Ueta; K. Tani; T. Kato

    2000-01-01

    Computerized X-ray tomography applied to sandbox experiments makes it possible to analyze the kinematic evolution, as well as the three-dimensional geometry, of faults in basement-controlled wrench faulting. With increasing basement displacement, the evolution of shear bands developed in the model sand bed is observed as follows. (1) The right-stepping shears that have a ‘cirque’ or ‘shell’ or ‘ship body’ shape

  20. Control of faults on the 3D coupled fluid and heat transport in a geothermal site (Gross Schönebeck, NE-German Basin)

    NASA Astrophysics Data System (ADS)

    Cherubini, Y.; Cacace, M.; Scheck-Wenderoth, M.

    2011-12-01

    Studies that quantify the influence of faults on the fluid and heat transfer in 3D are still sparse. Faults have a significant impact on physical processes controlling heat transfer and fluid motion in the subsurface as they disturb the conformal succession of geological layers. Depending on their hydraulic properties, faults can act either as preferential pathways or as barriers to fluid flow (Barton et al. 1995). It is important to understand the role of faults and their impact on the thermal field for exploitation of geothermal energy. We improved an existing 3D structural model of the geothermal site "Gross Schönebeck" (Moeck et al. 2005) to carry out coupled fluid and heat transfer simulations. The coupled non-linear partial differential equations describing fluid flow and heat transport in a saturated porous medium are numerically solved by the finite element software FEFLOW° (Diersch, 2002). Simulation results are validated with borehole data. The geological model covers an area of 55 x 50 km. It integrates 18 sedimentary layers of Carboniferous to Quaternary age and reaches down to 5 km depth. An up to 1200 m thick Upper Permian (Zechstein) salt layer decouples two fault systems. We focus on the subsalt fault system which comprises the reservoir target zone and which includes major NW-SE and minor NE-SW trending faults cutting the lower part of the model. The major intersecting faults of the subsalt system are integrated as vertical discrete elements within the numerical model. By discrimination of critically stressed and extensional faults within the current stress field, the hydraulic conductivity of the faults is assessed (Moeck et al. 2009). The impact of the main fault characterising parameters, - the permeability and effective width of the fault-, are investigated by sensitivity analyses. We present outcomes from these simulations by comparing them with results from conductive and coupled fluid and heat transfer simulations obtained from models that do not integrate faults. The results pioneer in that they treat the fault-induced transport of fluid and heat in 3D. We find that faults can strongly alter the fluid regime as well as the temperature evolution in response to their contrasting hydraulic properties with respect to the surrounding matrix.

  1. 3D current path in stacked devices: Metrics and challenges

    Microsoft Academic Search

    H. B. Kor; F. Infante; P. Perdu; C. L. Gan; D. Lewis

    2011-01-01

    Although magnetic current imaging (MCI) is useful in fault isolation of devices with 2D current distributions, MCI alone cannot give the exact information of current paths in complex 3D stacked devices. Previous work has demonstrated the ability of a simulation approach to find a short circuit in 3D geometry. This approach has been challenged in the case of dense and

  2. The Need (?) for Descriptive Geometry in a World of 3D Modeling.

    ERIC Educational Resources Information Center

    Croft, Frank M. Jr.

    1998-01-01

    Evaluates the use of modern CAD methods to solve geometric problems. Solves descriptive geometry problems using the layout and position of the successive auxiliary views from the projection of three-dimensional figures onto a two-dimensional plane of paper. (CCM)

  3. JASPERSE CHEM 341 TEST 1 VERSION 1 1. Draw the correct Lewis structure of CH3CN. (Needn't show 3-D geometry) (3pt)

    E-print Network

    Jasperse, Craig P.

    1 JASPERSE CHEM 341 TEST 1 VERSION 1 Ch. 1-4 1. Draw the correct Lewis structure of CH3CN. (Needn't show 3-D geometry) (3pt) 2. Draw the correct Lewis structure for HOCH2CHO. (Needn't show 3-D geometry). (3pt) 3. Draw a 3-dimensional picture for the atoms in CH3CO2CH2CH3, using the hash-wedge convention

  4. Fault Geometry at the Rupture Termination of the 1995 Hyogo-ken Nanbu Earthquake

    Microsoft Academic Search

    Haruko Sekiguchi; Kojiro Irikura; Tomotaka Iwata

    2000-01-01

    The source geometry and slip distribution at rupture termination of the 1995 Hyogo-ken Nanbu earthquake were investigated using waveform inversion on the assumption of fault branching in the northeastern part of the rupture model. Possible branching of the Okamoto fault is suggested both by the static-displacement distribution and damage extension east of Kobe (Nishinomiya area). To exclude data contaminated by

  5. The effects of realistic fault geometry on ground motion on the Claremont - Casa Loma stepover of the San Jacinto Fault

    NASA Astrophysics Data System (ADS)

    Lozos, J.; Oglesby, D. D.; Brune, J. N.; Olsen, K. B.

    2012-12-01

    The Claremont and Casa Loma strands of the San Jacinto Fault in southern California are separated by a 25 km long extensional stepover, which bounds a sedimentary basin. Both individual strands are themselves geometrically complex. A smaller fault strand is located within the stepover, approximately halfway between the two main strands. The width of the larger stepover approaches 4 km, which has been shown by prior observational and modeling work to be close to the upper limit for stepover width through which rupture may jump. The region within and surrounding the Claremont-Casa Loma stepover is densely populated, which further emphasizes the importance of understanding the rupture and shaking hazard associated with this fault system. We use the 3D finite element method to model dynamic ruptures on the Claremont-Casa Loma stepover, incorporating geometrical complexities based on the USGS Quaternary Fault Database and the SCEC Community Fault Model, in order to investigate the ability of the rupture to propagate through the geometrical complexities in this region, as well as the resulting ground motions. As compared to a stepover model with planar segments, the overall intensity and distribution of strong motion for the complex model is reduced, but there remains a region of decreased peak motions between the end of the nucleating fault and the second fault strand. In addition, rupture directivity is diminished near each bend in the fault. Due to this break in directivity, peak ground motions near the fault are weakest immediately after the rupture turns a bend, and are strongest and more widespread immediately before the next bend. Unlike the case of a stepover with planar segments, the shape and intensity of the ground motion distribution is not symmetrical across the fault; an alternating pattern of fault bends produces an alternating pattern for which side of the fault trace experiences higher ground motion. Future work will involve incorporating a complex 3D velocity structure based on the SCEC Community Velocity Model, which should significantly improve the accuracy of our ground motion estimates.

  6. Relation Between the 3D-Geometry of the Coronal Wave and Associated CME During the 26 April 2008 Event

    NASA Technical Reports Server (NTRS)

    Temmer, M.; Veronig, A. M.; Gopalswamy, N.; Yashiro, S.

    2011-01-01

    We study the kinematical characteristics and 3D geometry of a large-scale coronal wave that occurred in association with the 26 April 2008 flare-CME event. The wave was observed with the EUVI instruments aboard both STEREO spacecraft (STEREO-A and STEREO-B) with a mean speed of approx 240 km/s. The wave is more pronounced in the eastern propagation direction, and is thus, better observable in STEREO-B images. From STEREO-B observations we derive two separate initiation centers for the wave, and their locations fit with the coronal dimming regions. Assuming a simple geometry of the wave we reconstruct its 3D nature from combined STEREO-A and STEREO-B observations. We find that the wave structure is asymmetric with an inclination toward East. The associated CME has a deprojected speed of approx 750 +/- 50 km/s, and it shows a non-radial outward motion toward the East with respect to the underlying source region location. Applying the forward fitting model developed by Thernisien, Howard, and Vourlidas we derive the CME flux rope position on the solar surface to be close to the dimming regions. We conclude that the expanding flanks of the CME most likely drive and shape the coronal wave.

  7. 3D field solver in toroidal geometry for the long wavelength E&M modes

    NASA Astrophysics Data System (ADS)

    Janhunen, Salomon; Wang, Bei; Hesthaven, Jan; Adams, Mark; Ku, Seung-Hoe; Chang, Choong-Seock

    2014-10-01

    Gyrokinetic simulations - such as those performed by the XGC code - provide a self-consistent framework to investigate a wide range of physics in strongly magnetized high temperature laboratory plasmas, global modes usually considered to be in the realm of MHD simulations. However, the present simulation models generally concentrate on short wavelength electro-magnetic modes mostly to convenience the field solver performance. To incorporate more global fluid-like modes, also non-zonal long wavelength physics needs to be retained. In this work we present development of a fully 3D mixed FEM/FDM electro-magnetic field solver for the gyrokinetic code XGC1. We present optimization for use on massively parallel computational platforms, investigation of numerical accuracy characteristics using the method of manufactured solutions and evaluate the regime of validity for the current physics model. Center for Edge Physics Simulation.

  8. Laser cone beam computed tomography scanner geometry for large volume 3D dosimetry

    NASA Astrophysics Data System (ADS)

    Jordan, K. J.; Turnbull, D.; Batista, J. J.

    2013-06-01

    A new scanner geometry for fast optical cone-beam computed tomography is reported. The system consists of a low power laser beam, raster scanned, under computer control, through a transparent object in a refractive index matching aquarium. The transmitted beam is scattered from a diffuser screen and detected by a photomultiplier tube. Modest stray light is present in the projection images since only a single ray is present in the object during measurement and there is no imaging optics to introduce further stray light in the form of glare. A scan time of 30 minutes was required for 512 projections with a field of view of 12 × 18 cm. Initial performance from scanning a 15 cm diameter jar with black solutions is presented. Averaged reconstruction coefficients are within 2% along the height of the jar and within the central 85% of diameter, due to the index mismatch of the jar. Agreement with spectrometer measurements was better than 0.5% for a minimum transmission of 4% and within 4% for a dark, 0.1% transmission sample. This geometry's advantages include high dynamic range and low cost of scaling to larger (>15 cm) fields of view.

  9. 3D inclusion trail geometry determination within individual porphyroblasts using reflected light optical microscopy of oriented blocks

    NASA Astrophysics Data System (ADS)

    Munro, Mark; Bowden, Douglas; Ord, Alison; Hobbs, Bruce

    2015-04-01

    It is vital to interpret porphyroblast microstructures accurately relative to both one another and to external matrix structures when using them to reconstruct the tectono-metamorphic evolution of orogenic terranes. Mis-interpretation may have profound implications for either the deformation component or the inferred metamorphic reactions resulting in erroneous Pressure-Temperature-time-Deformation (P-T-t-D) trajectories. A number of well-established approaches have been devised for measuring porphyroblast inclusion trails including pitch and strike measurement, 'FitPitch' best-fit plane assignment, and the radial asymmetry method. A long-standing limitation of these methods is that they generally permit only a single measurement to be extracted from each individual porphyroblast, and therefore provide mean 3D orientation data for an entire population. Alternatively, High-Resolution X-ray Computed Tomography (HRXCT) facilitates the imaging of 3D internal geometries within individuals. However, at present significant operating costs render it unviable for routine application to large numbers of samples required for extracting meaningful tectonic interpretations. Here, a new method is presented for the determination of 3D geometries within porphyroblasts using reflected light examination of polished schist material. Reflected light microscopy yields good quality representation of inclusion trails preserved within porphyroblasts. Sectioning oriented samples into small, oriented blocks allows multiple intersections through porphyroblasts (generally >5mm) to be measured via mechanical stage and amalgamated to reconstruct the plane in 3D. The method represents an accessible alternative to HRXCT, which is applicable to any porphyroblastic phase of adequate size to permit at least two intersections. The technique is demonstrated on garnets from the Mesoproterozoic Mount Barren Group, southern Albany-Fraser orogen of S. W. Australia. Porphyroblasts within a structural domain of the Kybalup Schist member of the Mount Barren Group preserve two generations of foliation that have been largely overprinted in the matrix during the effects of subsequent deformation. The earliest generation (S1) was associated with approximately East-West oriented horizontal bulk shortening.

  10. Structural geometry of Raplee Ridge monocline and thrust fault imaged using inverse Boundary Element Modeling and ALSM data

    E-print Network

    Hilley, George

    Structural geometry of Raplee Ridge monocline and thrust fault imaged using inverse Boundary (ALSM) topographic data define the geometry of exposed marker layers within this fold. The spatial, and points on these surfaces were used to infer the underlying fault geometry and remote strain conditions

  11. High order spatial expansion for the method of characteristics applied to 3-D geometries

    SciTech Connect

    Naymeh, L.; Masiello, E.; Sanchez, R. [CEA/DEN/DM2S, SERMA/LSTD, Centre de Saclay, PC 57, 91191 Gif-sur-Yvette cedex (France)

    2013-07-01

    The method of characteristics is an efficient and flexible technique to solve the neutron transport equation and has been extensively used in two-dimensional calculations because it permits to deal with complex geometries. However, because of a very fast increase in storage requirements and number of floating operations, its direct application to three-dimensional routine transport calculations it is not still possible. In this work we introduce and analyze several modifications aimed to reduce memory requirements and to diminish the computing burden. We explore high-order spatial approximation, the use of intermediary trajectory-dependent flux expansions and the possibility of dynamic trajectory reconstruction from local tracking for typed subdomains. (authors)

  12. Fault superimposition and linkage resulting from stress changes during rifting: Examples from 3D seismic data, Phitsanulok Basin, Thailand

    NASA Astrophysics Data System (ADS)

    Morley, C. K.; Gabdi, S.; Seusutthiya, K.

    2007-04-01

    The Phitsanulok basin, Thailand provides examples of changing fault displacement patterns with time associated with faults of different orientations. In the Northern Phitsanulok basin three main stress states have been identified associated with Late Oligocene-Recent fault development: (1) Late Oligocene-Late Miocene approximately E-W extension (N-S Shmax), 'main rift' stage, (2) Late Miocene-Pliocene transtension to tranpression (?) (E-W to NE-SW Shmax), 'late rift' stage, and (3) Pliocene-Recent very minor faulting, E-W extension, N-S Shmax, 'post-rift' stage. Syn-rift faults tend to strike N-S, but also follow NE-SW and NW-SE trends and are basement involved. The Late Miocene deformation produced a distinctly different type of fault population from the main rift fault set, characterized by numerous, small displacement (tens of metres), faults striking predominantly NE-SW. Most of these faults are convergent, conjugate sets aligned in discrete zones and nucleated within the sedimentary basin. Reactivation of main rift faults trends during the late rift stage favoured strike directions between 350° and 50°. The displacement characteristics of three large faults within the basin show variations depending upon fault orientation. The low-angle (23°-30° dip), Western Boundary Fault (˜7 km throw) displays little discernible difference in the distribution of displacement on fault zone during the different stress states other than increases and decreases in displacement amount. Smaller faults exhibit a more selective reactivation history than the Western Boundary fault and are more informative about fault response to a varying stress field. Activation of the (oblique) NE-SW striking NTM-1 initially produced a fault divided into three segments, splaying into N-S trends. Stress reorientation during the late rift stage finally linked NE-SW striking segments. The partial linkage of the fault zone at the time of oil migration resulted in the southwestern part of the NTM-1 fault sealing hydrocarbon bearing reservoirs, whilst late linkage areas along the northeastern part failed to seal hydrocarbons. The N-S striking PTO-1 Fault shows early isolated fault segments, linkage during syn-rift motion, then a more patchy distribution of displacement late in the fault history, perhaps due to non-optimal orientation of the fault to the regional stress field, when compared with the NTM-1 Fault. The fault characteristics described indicate that where strong pre-existing fabrics are present, and varying stress regimes have occurred, fault population characteristics and evolution of fault displacement can depart considerably from extensional fault populations associated with a single phase of extension.

  13. 3D geometry and quantitative variation of the cervico-thoracic region in Crocodylia.

    PubMed

    Chamero, Beatriz; Buscalioni, Angela D; Marugán-Lobón, Jesús; Sarris, Ioannis

    2014-07-01

    This study aims to interpret the axial patterning of the crocodylian neck, and to find a potential taxonomic signal that corresponds to vertebral position. Morphological variation in the cervico-thoracic vertebrae is compared in fifteen different crocodylian species using 3D geometric morphometric methods. Multivariate analysis indicated that the pattern of intracolumnar variation was a gradual change in shape of the vertebral series (at the parapophyses, diapophyses, prezygapohyses, and postzygapohyses), in the cervical (C3 to C9) and dorsal (D1-D2) regions which was quite conservative among the crocodylians studied. In spite of this, we also found that intracolumnar shape variation allowed differentiation between two sub regions of the crocodylian neck. Growth is subtly correlated with vertebral shape variation, predicting changes in both the vertebral centrum and the neural spine. Interestingly, the allometric scaling for the pooled sample is equivalently shared by each vertebra studied. However, there were significant taxonomic differences, both in the average shape of the entire neck configuration (regional variation) and by shape variation at each vertebral position (positional variation) among the necks. The average neck vertebra of crocodylids is characterized by a relatively cranio-caudally short neural arch, whereby the spine is relatively longer and pointed orthogonal to the frontal plane. Conversely, the average vertebra in alligatorids has cranio-caudally longer neural spine and arch, with a relatively (dorso-ventrally) shorter spine. At each vertebral position there are significant differences between alligatorids and crocodylids. We discuss that the delayed timing of neurocentral fusion in Alligatoridae possibly explains the observed taxonomic differences. PMID:24753482

  14. 3D features of delayed thermal convection in fault zones: consequences for deep fluid processes in the Tiberias Basin, Jordan Rift Valley

    NASA Astrophysics Data System (ADS)

    Magri, Fabien; Möller, Sebastian; Inbar, Nimrod; Siebert, Christian; Möller, Peter; Rosenthal, Eliyahu; Kühn, Michael

    2015-04-01

    It has been shown that thermal convection in faults can also occur for subcritical Rayleigh conditions. This type of convection develops after a certain period and is referred to as "delayed convection" (Murphy, 1979). The delay in the onset is due to the heat exchange between the damage zone and the surrounding units that adds a thermal buffer along the fault walls. Few numerical studies investigated delayed thermal convection in fractured zones, despite it has the potential to transport energy and minerals over large spatial scales (Tournier, 2000). Here 3D numerical simulations of thermally driven flow in faults are presented in order to investigate the impact of delayed convection on deep fluid processes at basin-scale. The Tiberias Basin (TB), in the Jordan Rift Valley, serves as study area. The TB is characterized by upsurge of deep-seated hot waters along the faulted shores of Lake Tiberias and high temperature gradient that can locally reach 46 °C/km, as in the Lower Yarmouk Gorge (LYG). 3D simulations show that buoyant flow ascend in permeable faults which hydraulic conductivity is estimated to vary between 30 m/yr and 140 m/yr. Delayed convection starts respectively at 46 and 200 kyrs and generate temperature anomalies in agreement with observations. It turned out that delayed convective cells are transient. Cellular patterns that initially develop in permeable units surrounding the faults can trigger convection also within the fault plane. The combination of these two convective modes lead to helicoidal-like flow patterns. This complex flow can explain the location of springs along different fault traces of the TB. Besides being of importance for understanding the hydrogeological processes of the TB (Magri et al., 2015), the presented simulations provide a scenario illustrating fault-induced 3D cells that could develop in any geothermal system. References Magri, F., Inbar, N., Siebert, C., Rosenthal, E., Guttman, J., Möller, P., 2015. Transient simulations of large-scale hydrogeological processes causing temperature and salinity anomalies in the Tiberias Basin. Journal of Hydrology, 520(0), 342-355. Murphy, H.D., 1979. Convective instabilities in vertical fractures and faults. Journal of Geophysical Research: Solid Earth, 84(B11), 6121-6130. Tournier, C., Genthon, P., Rabinowicz, M., 2000. The onset of natural convection in vertical fault planes: consequences for the thermal regime in crystalline basementsand for heat recovery experiments. Geophysical Journal International, 140(3), 500-508.

  15. Fault and joint geometry at Raft River geothermal area, Idaho

    SciTech Connect

    Guth, L.R.; Bruhn, R.L.; Beck, S.L.

    1981-07-01

    Raft River geothermal reservoir is formed by fractures in sedimentary strata of the Miocene and Pliocene Salt Lake Formation. The fracturing is most intense at the base of the Salt Lake Formation, along a decollement that dips eastward at less than 5/sup 0/ on top of metamorphosed Precambrian and Lower Paleozoic rocks. Core taken from less than 200 m above the decollement contains two sets of normal faults. The major set of faults dips between 50/sup 0/ and 70/sup 0/. These faults occur as conjugate pairs that are bisected by vertical extension fractures. The second set of faults dips 10/sup 0/ to 20/sup 0/ and may parallel part of the basal decollement or reflect the presence of listric normal faults in the upper plate. Surface joints form two suborthogonal sets that dip vertically. East-northeast-striking joints are most frequent on the limbs of the Jim Sage anticline, a large fold that is associated with the geothermal field. The north-trending joint set is prominent in the fold's hinge. Surface joint intensity decreases in proximity to known faults, indicating that surface joint intensity mapping may be useful for locating the surface traces of faults in the reservoir.

  16. In vitro analog of human bone marrow from 3D scaffolds with biomimetic inverted colloidal crystal geometry

    PubMed Central

    Nichols, Joan E.; Cortiella, Joaquin; Lee, Jungwoo; Niles, Jean A.; Cuddihy, Meghan; Wang, Shaopeng; Cantu, Andrea; Mlcak, Ron; Valdivia, Esther; Yancy, Ryan; Bielitzki, Joseph; McClure, Matthew L.; Kotov, Nicholas A.

    2009-01-01

    In vitro replicas of bone marrow can potentially provide a continuous source of blood cells for transplantation and serve as a laboratory model to examine human immune system dysfunctions and drug toxicology. Here we report the development of an in vitro artificial bone marrow based on a 3D scaffold with inverted colloidal crystal (ICC) geometry mimicking the structural topology of actual bone marrow matrix. To facilitate adhesion of cells, scaffolds were coated with a layer of transparent nanocomposite. After seeding with hematopoietic stem cells (HSCs), ICC scaffolds were capable of supporting expansion of CD34+ HSCs with B-lymphocyte differentiation. Three-dimensional organization was shown to be critical for production of B cells and antigen specific-antibodies. Functionality of bone marrow constructs was confirmed by implantation of matrices containing human CD34+ cells onto the backs of severe combined immunodeficiency (SCID) mice with subsequent generation of human immune cells. PMID:19042018

  17. Validation and Analysis of Forward Osmosis CFD Model in Complex 3D Geometries

    PubMed Central

    Gruber, Mathias F.; Johnson, Carl J.; Tang, Chuyang; Jensen, Mogens H.; Yde, Lars; Hélix-Nielsen, Claus

    2012-01-01

    In forward osmosis (FO), an osmotic pressure gradient generated across a semi-permeable membrane is used to generate water transport from a dilute feed solution into a concentrated draw solution. This principle has shown great promise in the areas of water purification, wastewater treatment, seawater desalination and power generation. To ease optimization and increase understanding of membrane systems, it is desirable to have a comprehensive model that allows for easy investigation of all the major parameters in the separation process. Here we present experimental validation of a computational fluid dynamics (CFD) model developed to simulate FO experiments with asymmetric membranes. Simulations are compared with experimental results obtained from using two distinctly different complex three-dimensional membrane chambers. It is found that the CFD model accurately describes the solute separation process and water permeation through membranes under various flow conditions. It is furthermore demonstrated how the CFD model can be used to optimize membrane geometry in such as way as to promote the mass transfer. PMID:24958428

  18. Oblique And Orthogonal Amagmatic Accretionary Ridges: Improbable Fault Geometries?

    NASA Astrophysics Data System (ADS)

    Dick, H. J.

    2006-12-01

    Amagmatic accretionary segments, where the mantle is directly emplaced to the seafloor, constitute the third class of stable plate boundary structure, along with transforms and magmatic ridge segments at ocean ridges. While transforms extend plate boundaries in the direction of plate spreading and magmatic accretionary segments extend them sub-perpendicular to it, amagmatic accretionary segments can assume any orientation to the plate spreading direction; locally replacing both transform faults and magmatic ridge segments. The primary terrain-forming boundary faults along amagmatic segments form at improbable dips and strikes to the plate spreading direction; likely representing the end-member case for plate failure from the base rather than the top. Where the tectonic plates are thin, as at the fast spreading EPR, first-order ridge segments trend perpendicular to the spreading direction, indicating plate failure from the top. At slow ridges, first-order segments are often oblique to the spreading direction, as along the Reykjanes Ridge. There, individual second-order segments arrange themselves en-echelon, sub-perpendicular to the spreading direction, linking with the oblique boundary faults parallel the rift to form one integrated set of faults and fissures to accommodate extension. This reflects plate failure influenced by plate weakening along the zone of lithospheric necking at the base of the plate, as well as brittle failure at the top. At ultraslow ridges (<20 mm/yr), however, where the effective spreading rate is less than ~12 mm/yr, and the weakening influence of melt in the lithosphere is nearly absent, oblique amagmatic spreading segments form, linking to magmatic segments to locally form curvilinear plate boundaries. High-angle normal faults are abundant, but form independent of low-angle boundary faults, becoming prominent terrain-forming features only at the magmatic segments. Linking of amagmatic and magmatic segments resembles ridge-transform intersections, with hooked volcanic ridges and curved fault scarps forming at obtuse wall intersections where high and low angle faults interact. This corresponds to the outside-corner highs of ridge-transform intersections, while the corresponding reflex wall intersection, corresponds to inside-corner highs at ridge-transform intersections. There oblique low-angle boundary faults and magmatic segment high-angle boundary faults cut each other. Where the ridge is perpendicular to spreading, as at Gakkel Ridge, amagmatic segments may or may not similarly link to magmatic segments, and orthogonal normal faults are rare along amagmatic segments. This likely explains the scarcity of hydrothermal plumes as compared to the magmatic segments, as high-angle faults form in the brittle regime and likely localize hydrothermal circulation.

  19. Three-dimensional splay fault geometry and implications for tsunami generation.

    PubMed

    Moore, G F; Bangs, N L; Taira, A; Kuramoto, S; Pangborn, E; Tobin, H J

    2007-11-16

    Megasplay faults, very long thrust faults that rise from the subduction plate boundary megathrust and intersect the sea floor at the landward edge of the accretionary prism, are thought to play a role in tsunami genesis. We imaged a megasplay thrust system along the Nankai Trough in three dimensions, which allowed us to map the splay fault geometry and its lateral continuity. The megasplay is continuous from the main plate interface fault upwards to the sea floor, where it cuts older thrust slices of the frontal accretionary prism. The thrust geometry and evidence of large-scale slumping of surficial sediments show that the fault is active and that the activity has evolved toward the landward direction with time, contrary to the usual seaward progression of accretionary thrusts. The megasplay fault has progressively steepened, substantially increasing the potential for vertical uplift of the sea floor with slip. We conclude that slip on the megasplay fault most likely contributed to generating devastating historic tsunamis, such as the 1944 moment magnitude 8.1 Tonankai event, and it is this geometry that makes this margin and others like it particularly prone to tsunami genesis. PMID:18006743

  20. Neural-network calibration of a multiple-line laser-camera range sensor for 3D surface-geometry measurement

    NASA Astrophysics Data System (ADS)

    Liu, Chris Yu-Liang; Kofman, Jonathan

    2008-11-01

    Single-line laser-camera range sensors require scanning over the object surface to measure three-dimensional (3D) surface geometry. Full-field 3D surface measurement techniques typically require more than one pattern to be projected and captured by camera. This paper presents a method to calibrate a multiple-line laser-camera range sensor using an artificial neural network (NN) to enable capture of full-field 3D surface geometry using a single projected pattern. The range sensor projects nineteen laser lines onto a surface. During calibration, points in 2D images are extracted from the intersections of nineteen laser profiles and horizontal lines marked on a calibration plate, for several calibration plate positions. A mapping of 2D image coordinates to 3D object coordinates is performed separately for each laser-line projection using a multi-layer perceptron (MLP) neural network. Experiments using different NN configurations found a network with two hidden layers of 43 nodes per layer using the sigmoidal activation function to generate the lowest 3D reconstruction errors. Errors were consistent errors over all calibration positions. Calibration with an acceptable error for many applications can be achieved without knowledge of the camera pose. The fast 3D reconstruction by the trained system may permit low resolution full-field 3D surface-geometry measurement in real-time.

  1. Assessing fault displacement and off-fault deformation in an extensional tectonic setting using 3-D ground-penetrating radar imaging

    Microsoft Academic Search

    M. Christie; G. P. Tsoflias; D. F. Stockli; R. Black

    2009-01-01

    High-resolution geophysical imaging can aid in the study of active faults by providing subsurface information about the geologic structure and deformational patterns present. We collected ground-penetrating radar (GPR) data across the active Emigrant Peak Fault in order to image and quantify fault displacement and assess off-fault deformation in an alluvial fan setting. The Emigrant Peak Fault in Fish Lake Valley,

  2. Exploration of Wadi Zerka Ma'in rotational fault and its drainage pattern, Eastern of Dead Sea, by means of remote sensing, GIS and 3D geological modeling

    NASA Astrophysics Data System (ADS)

    Odeh, Taleb; Gloaguen, Richard; Schirmer, Mario; Geyer, Stefan; Rödiger, Tino; Siebert, Christian

    2009-09-01

    The Wadi Zerka Ma'in catchment area is located in the North East of the Dead Sea. It contains a confined river of about 23 km length. The region is characterized by a recent sharp base level drop and a strong orographic control on climatic parameters such as temperature and precipitation. It is controlled by three regional structural systems as follow: 1) the anticline - syncline system (late Cretaceous - end of Miocene) which is a part of Syrian fold arc system; 2) NW - SE faults system which were generated simultaneously and parallel to the Red Sea spreading; 3) NWW - SSE faults system which are perpendicular to the Dead Sea and younger than the Red Sea fault system; 4) NNW - SSE faults system (middle Miocene - until now) which were generated simultaneously and parallel to the active Dead Sea transform fault. The structural setting of the study area was evaluated by means of a three-dimensional (3D) geological model, a digital elevation model (DEM) with resolutions 15 meters and stream profile analysis. DEM generation was performed using ASTER data. We found that the Wadi is located at the junction of two main fault systems. The major feature is a trans-tensional fault displacement which changes from 0 to 200 m. We showed that the catchment area is a result of a rotational fault while the river changes its flow direction according to the different fault system directions. The lower portion of the basin is affected by the major base level drops and display contributing rivers in exceptional non-equilibrium. Thus this catchment allows observing the rapid adaptation of the drainage system to both climatic and tectonic forcing.

  3. 3D Geometrical Inspection of Complex Geometry Parts Using a Novel Laser Triangulation Sensor and a Robot

    PubMed Central

    Brosed, Francisco Javier; Aguilar, Juan José; Guillomía, David; Santolaria, Jorge

    2011-01-01

    This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly “coupled” as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a “zero” or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy. PMID:22346569

  4. Basement Structure Controls on the Evolution and Geometry of Rift Systems - Insights from Offshore S. Norway using 3D Seismic Data

    NASA Astrophysics Data System (ADS)

    Phillips, Thomas; Jackson, Christopher; Bell, Rebecca; Duffy, Oliver; Fossen, Haakon

    2015-04-01

    Rift basins form within lithosphere containing a range of heterogeneities, such as thin-skinned thrust belts and larger scale structures such as thick-skinned shear zones or crustal sutures. How the presence and reactivation of these structures during later rift events affect the geometry and evolution of rifts remains poorly understood as they are not typically well imaged on seismic data. The main reasons for this are that crystalline basement is often buried beneath thick sedimentary successions and contains small impedance contrasts. Furthermore, larger, crustal-scale, lineaments and sutures may not be imaged at all on seismic data due to their large scale and depth. In this study, we use borehole-constrained 2D and 3D seismic reflection data located around the Egersund and Farsund Basins, offshore south Norway. In both areas, crystalline basement is exceptionally well-imaged on typical 2D and 3D reflection data due to large impedance contrasts within a highly heterogeneous, shallow basement. This allows us to map a series of intrabasement reflections and overlying rift systems. Within the Egersund area, two main types of intrabasement structure are identified and mapped: i) thin (100 m), shallowly dipping (0-10°W) reflections showing a ramp-flat geometry; and ii) thick (1-1.5 km), low angle (c. 30°W) structures comprising of packages of reflections. These structures correlate along-strike northwards to Caledonian orogeny related structures mapped onshore Norway. The thin structures are interpreted as thin-skinned Caledonian thrusts, whereas the thicker structures represent thick-skinned Devonian shear zones formed through orogenic collapse of the Caledonides. Through seismic-stratigraphic analysis of the cover, we document multiple stages of extensional reactivation along these structures during Devonian, Permian-Triassic and Late Jurassic-Early Cretaceous extension followed by reverse reactivation during Late Cretaceous compression. The Farsund Basin is situated above a deep crustal-scale lineament, the Tornquist zone. We also document multiple stages of reactivation and inversion within this basin, linked with motion along the underlying lineament. Reactivation of the Tornquist zone at depth leads to the formation of a deep, narrow basin at shallower levels. However, during reactivation, rift propagation may be inhibited by basement heterogeneities, such as pre-existing basement ridges. We find that the type of reactivated structure can exert a strong control on the geometry and evolution of the overlying rift. Low-angle, thin-skinned Caledonian thrusts have negligible effect on rift evolution as these are not readily reactivated. However, reactivation of thick-skinned structures does affect rift morphology. Direct reactivation of low angle Devonian shear zones forms a series of low angle rift-bounding faults, creating a wide, shallow basin. Conversely, reactivation of deep seated crustal lineaments causes the localisation of strain fields, creating deep, narrow basins. In both cases, the presence of these thick skinned structures acts as a template for the location of later rifts; their subsequent reactivation can then control the rift geometry.

  5. Characterization and 3-D modeling of Ni60Ti SMA for actuation of a variable geometry jet engine chevron

    NASA Astrophysics Data System (ADS)

    Hartl, Darren J.; Lagoudas, Dimitris C.

    2007-04-01

    This work describes the thermomechanical characterization and FEA modeling of commercial jet engine chevrons incorporating active Shape Memory Alloy (SMA) beam components. The reduction of community noise at airports generated during aircraft take-off has become a major research goal. Serrated aerodynamic devices along the trailing edge of a jet engine primary and secondary exhaust nozzle, known as chevrons, have been shown to greatly reduce jet noise by encouraging advantageous mixing of the streams. To achieve the noise reduction, the secondary exhaust nozzle chevrons are typically immersed into the fan flow which results in drag, or thrust losses during cruise. SMA materials have been applied to this problem of jet engine noise. Active chevrons, utilizing SMA components, have been developed and tested to create maximum deflection during takeoff and landing while minimizing deflection into the flow during the remainder of flight, increasing efficiency. Boeing has flight tested one Variable Geometry Chevron (VGC) system which includes active SMA beams encased in a composite structure with a complex 3-D configuration. The SMA beams, when activated, induce the necessary bending forces on the chevron structure to deflect it into the fan flow and reduce noise. The SMA composition chosen for the fabrication of these beams is a Ni60Ti40 (wt%) alloy. In order to calibrate the material parameters of the constitutive SMA model, various thermomechanical experiments are performed on trained (stabilized) standard SMA tensile specimens. Primary among these tests are thermal cycles at various constant stress levels. Material properties for the shape memory alloy components are derived from this tensile experimentation. Using this data, a 3-D FEA implementation of a phenomenological SMA model is calibrated and used to analyze the response of the chevron. The primary focus of this work is the full 3-D modeling of the active chevron system behavior by considering the SMA beams as fastened to the elastic chevron structure. Experimental and numerical results are compared. Discussion is focused on actuation properties such as tip deflection and chevron bending profile. The model proves to be an accurate tool for predicting the mechanical response of such a system subject to defined thermal inputs.

  6. Control of fault geometry and permeability contrast on fault-related hydrothermal fluid flow

    NASA Astrophysics Data System (ADS)

    Andersen, Christine; Rüpke, Lars; Hasenclever, Jörg; Grevemeyer, Ingo; Petersen, Sven

    2015-04-01

    High-temperature black smoker systems along slow-spreading ridges such as the Mid-Atlantic Ridge (MAR) are frequently related to tectonic fault zones and therefore are commonly found off axis. While preferential flow of hot fluids along highly permeable, fractured rocks seems intuitive, such efficient flow leads to the entrainment of cold ambient seawater resulting in a drastic decrease in vent temperatures. This temperature drop is difficult to reconcile with high-temperature black smoker activity observed at outcropping fault zones. In our recent study we aim to resolve this apparent contradiction by combining newly acquired seismological data (Grevemeyer et al., 2013) from the high-temperature, off-axis Logatchev 1 hydrothermal field (LHF1) along the MAR with 2D hydrothermal flow modeling. The seismic data shows intense off-axis seismicity with focal mechanisms suggesting a fault zone dipping from LHF1 toward the ridge axis. In order to explain fault-related high-temperature hydrothermal discharge as observed at LHF1, our simulations predict that fault zones need to be just permeable and wide enough to capture and redirect hydrothermal plumes rising from depth but, because they are not isolated conduits, must not be too wide or permeable in order to prevent cooling through mixing with ambient colder fluids. The two controlling parameters fault width and permeability contrast between fault and surrounding rock can be expressed as a single term, the relative transmissibility of the fault zone, which is defined by the product of the two. Low relative fault transmissibility leads to plumes that cross the fault and vent above the heat source rather than at the fault termination at the seafloor. High relative fault transmissibility leads to significantly lower vent exit temperatures than those observed at black smoker systems. Our findings further illustrate the intrinsic relationship between permeability, mass flux and upflow temperature: the higher the permeability, the higher the mass flux and the lower the vent temperature. The common occurrence of fault-linked high-temperature vent fields strongly points at a not-yet-quantified self-adjusting permeability that depends on pore space-clogging reactions between hydrothermal and ambient cold fluids. Furthermore, the temperature drop associated with any high permeability zone in heterogeneous crust may well explain the sparse high-temperature vent fields along the MAR and why the heterogeneous crust of the Atlantic, with its strong permeability contrasts, is predominantly cooled by lower-temperature fluid flow.

  7. Detailed characterization of 2D and 3D scatter-to-primary ratios of various breast geometries using a dedicated CT mammotomography system

    NASA Astrophysics Data System (ADS)

    Shah, Jainil; Pachon, Jan H.; Madhav, Priti; Tornai, Martin P.

    2011-03-01

    With a dedicated breast CT system using a quasi-monochromatic x-ray source and flat-panel digital detector, the 2D and 3D scatter to primary ratios (SPR) of various geometric phantoms having different densities were characterized in detail. Projections were acquired using geometric and anthropomorphic breast phantoms. Each phantom was filled with 700ml of 5 different water-methanol concentrations to simulate effective boundary densities of breast compositions from 100% glandular (1.0g/cm3) to 100% fat (0.79g/cm3). Projections were acquired with and without a beam stop array. For each projection, 2D scatter was determined by cubic spline interpolating the values behind the shadow of each beam stop through the object. Scatter-corrected projections were obtained by subtracting the scatter, and the 2D SPRs were obtained as a ratio of the scatter to scatter-corrected projections. Additionally the (un)corrected data were individually iteratively reconstructed. The (un)corrected 3D volumes were subsequently subtracted, and the 3D SPRs obtained from the ratio of the scatter volume-to-scatter-corrected (or primary) volume. Results show that the 2D SPR values peak in the center of the volumes, and were overall highest for the simulated 100% glandular composition. Consequently, scatter corrected reconstructions have visibly reduced cupping regardless of the phantom geometry, as well as more accurate linear attenuation coefficients. The corresponding 3D SPRs have increased central density, which reduces radially. Not surprisingly, for both 2D and 3D SPRs there was a dependency on both phantom geometry and object density on the measured SPR values, with geometry dominating for 3D SPRs. Overall, these results indicate the need for scatter correction given different geometries and breast densities that will be encountered with 3D cone beam breast CT.

  8. The foundation of 3D geometry model in omni-directional laser warning system based on diffuse reflection detection

    NASA Astrophysics Data System (ADS)

    Zhang, Weian; Wang, Long; Dong, Qixin

    2011-06-01

    The omni-directional laser warning equipment based on infrared fish-eye lens and short-wave infrared FPA has been used to protect large-scale targets, which can detect the threat laser scattered by the attacked targets or the objects surrounding them, and image the laser spot on FPA, then fix the position of spot. The application offsets the disadvantage of direct interception warner which need disposed largely. Before study of imaging mechanism about the scattered laser spot, the definition of geometry relationship is needed firstly. In this paper we developed a 3D geometry model by analyzing the position relationships in typical battlefield environment among the enemy's threat laser source, the laser spot radiated on one flat surface and our omni-directional laser warning fish-eye lens. The model including R, ?, ?, d, ?, ?, ?, ? etc. 8 parameters and 4 coordinate systems was suitable for any general situations. After achievement of the model foundation, we obtained analytic expression of the laser spot contour on flat surface, then attained analytic expression of spot contour on image surface by calculating the object space half-field angle and the azimuth angle relative to fish-eye lens of an arbitrary point at the spot edge on flat surface. The attainment of the expression makes possible that we can analyze the spot energy distributions on image surface and the imaging characteristic of the scattered laser spot via fish-eye lens, then can compute the transmission direction of the threat laser. The foundation of the model in this paper has an importantly basic and guiding meaning to the latter research on this aspect.

  9. Application of a new 3D Finite-element Elasto-visco-plastic Modeling Technique to Simulate Origination and Evolution of the San Andreas Fault System

    NASA Astrophysics Data System (ADS)

    Popov, A.; Sobolev, S.; Zoback, M.

    2006-12-01

    The San Andreas Fault System (SAFS) in central and northern California is a complex of faults that accommodate the relative motion between the Pacific plate and the North American plate. This system began to develop about 20 Myr ago in response to the northward migration of the Mendocino triple junction. As the triple junction migrated northward along the plate boundary, the slab being subducted beneath North America was replaced by hot asthenospheric material in a slab window or slab gap and the transform deformation along the plate boundary developed simultaneously with thermal re-equilibration of the lithosphere. Large spatial (several 100 km) and temporal (20 Myr) scale, as well as essentially 3D style and strongly non-linear character of the associated brittle-ductile deformation processes require new efficient modeling technique. Our approach is based on the implicit time integration of momentum, mass and energy conservation equations and employs temperature- and stress-dependant elastoviscoplastic rheology. The code called SLIM3D ( Semi-Lagrangian Implicit Modeler) combines Lagrangian formulations and particle-based remeshing procedure. The locking-free hexahedral finite element with hourglass control is adopted to maintain robustness and efficiency of computation. The notion of consistent linearization of stress update algorithm and derivation of tangent modulus tensor is used to achieve optimal convergence rate of global Newton-Raphson equilibrium iteration at a large time step. First results of a full 3D modeling demonstrate that the general features of the SAFS can indeed result from strike-slip deformation of the continental margin subjected to the strong heating and then cooling according to the "slab-window" scenario. The key factor controlling spacing of the major faults is the amount of friction weakening achieved at the major faults, in accord with the results of our previous extended 2D models. The model-predicted faults distribution as well as deformation and thermal patterns are consistent with the SAFS, if friction coefficient at faults can be decreased at high shear strain by at least 3-5 times relative to its usual value of 0.5-0.7. We also discuss effects on SAFS deformation patterns of 3D lithospheric heterogeneity of North America margin and boundary tractions imposed by the Gorda plate.

  10. Stagnant lid convection in 3D-Cartesian geometry: Scaling laws and applications to icy moons and dwarf planets

    NASA Astrophysics Data System (ADS)

    Deschamps, Frédéric; Lin, Ja-Ren

    2014-04-01

    We conducted numerical experiments of stagnant lid thermal convection in 3D-Cartesian geometry, and use these experiments to derive parameterizations for the average internal temperature, heat flux, and stagnant lid thickness. Our experiments suggest that the non-dimensional temperature jump across the bottom thermal boundary layer (TBL) is well described by (1-?m)=1.23(?Tv/?T), where ?m is the non-dimensional average temperature of the convective sublayer, and ?Tv/?T a viscous temperature scale defined as the inverse of the logarithmic temperature derivative of viscosity. Due to the presence of the stagnant lid at the top of the fluid, the frequency of the time-variations of the surface heat flux is much lower than those of the bottom heat flux. The Nusselt number, measuring the heat transfer, is well explain by Nu=1.46Ram0.270(, where Ram is the effective Rayleigh number. This result indicates that the heat flux through the outer ice shells of large icy moons and dwarf planets is larger than that predicted by scalings in 2D-Cartesian geometry by 20-40%. We then apply our parameterizations to the dynamics of the outer ice I shells of icy moons and dwarf planets. As pointed out in previous studies, our calculations indicate that the presence of volatile in the primordial ocean of these bodies strongly reduces the vigor of convection within their outer ice I shell, the heat transfer through these shells, and the tectonic activity at their surface. Furthermore, thicker ice I layers may be achieved in bodies having low (0.7 m/s2) gravity acceleration (e.g., Pluto), than in bodies having larger (1.3 m/s2 and more) gravity acceleration (e.g., Europa, Ganymede, and Titan). Decrease in the surface temperature increases the thickness of the stagnant lid, which may result in a stronger lithosphere, and thus in fewer tectonic activity. Our parameterizations may also be used as boundary conditions at zero curvature to build parameterizations in spherical geometry.

  11. The Development of WARP - A Framework for Continuous Energy Monte Carlo Neutron Transport in General 3D Geometries on GPUs

    NASA Astrophysics Data System (ADS)

    Bergmann, Ryan

    Graphics processing units, or GPUs, have gradually increased in computational power from the small, job-specific boards of the early 1990s to the programmable powerhouses of today. Compared to more common central processing units, or CPUs, GPUs have a higher aggregate memory bandwidth, much higher floating-point operations per second (FLOPS), and lower energy consumption per FLOP. Because one of the main obstacles in exascale computing is power consumption, many new supercomputing platforms are gaining much of their computational capacity by incorporating GPUs into their compute nodes. Since CPU-optimized parallel algorithms are not directly portable to GPU architectures (or at least not without losing substantial performance), transport codes need to be rewritten to execute efficiently on GPUs. Unless this is done, reactor simulations cannot take full advantage of these new supercomputers. WARP, which can stand for ``Weaving All the Random Particles,'' is a three-dimensional (3D) continuous energy Monte Carlo neutron transport code developed in this work as to efficiently implement a continuous energy Monte Carlo neutron transport algorithm on a GPU. WARP accelerates Monte Carlo simulations while preserving the benefits of using the Monte Carlo Method, namely, very few physical and geometrical simplifications. WARP is able to calculate multiplication factors, flux tallies, and fission source distributions for time-independent problems, and can run in both criticality or fixed source modes. WARP can transport neutrons in unrestricted arrangements of parallelepipeds, hexagonal prisms, cylinders, and spheres. WARP uses an event-based algorithm, but with some important differences. Moving data is expensive, so WARP uses a remapping vector of pointer/index pairs to direct GPU threads to the data they need to access. The remapping vector is sorted by reaction type after every transport iteration using a high-efficiency parallel radix sort, which serves to keep the reaction types as contiguous as possible and removes completed histories from the transport cycle. The sort reduces the amount of divergence in GPU ``thread blocks,'' keeps the SIMD units as full as possible, and eliminates using memory bandwidth to check if a neutron in the batch has been terminated or not. Using a remapping vector means the data access pattern is irregular, but this is mitigated by using large batch sizes where the GPU can effectively eliminate the high cost of irregular global memory access. WARP modifies the standard unionized energy grid implementation to reduce memory traffic. Instead of storing a matrix of pointers indexed by reaction type and energy, WARP stores three matrices. The first contains cross section values, the second contains pointers to angular distributions, and a third contains pointers to energy distributions. This linked list type of layout increases memory usage, but lowers the number of data loads that are needed to determine a reaction by eliminating a pointer load to find a cross section value. Optimized, high-performance GPU code libraries are also used by WARP wherever possible. The CUDA performance primitives (CUDPP) library is used to perform the parallel reductions, sorts and sums, the CURAND library is used to seed the linear congruential random number generators, and the OptiX ray tracing framework is used for geometry representation. OptiX is a highly-optimized library developed by NVIDIA that automatically builds hierarchical acceleration structures around user-input geometry so only surfaces along a ray line need to be queried in ray tracing. WARP also performs material and cell number queries with OptiX by using a point-in-polygon like algorithm. WARP has shown that GPUs are an effective platform for performing Monte Carlo neutron transport with continuous energy cross sections. Currently, WARP is the most detailed and feature-rich program in existence for performing continuous energy Monte Carlo neutron transport in general 3D geometries on GPUs, but compared to production codes like Serpent and MCNP, WARP ha

  12. The role of fault surface geometry in the evolution of the fault deformation zone: comparing modeling with field example from the Vignanotica normal fault (Gargano, Southern Italy).

    NASA Astrophysics Data System (ADS)

    Maggi, Matteo; Cianfarra, Paola; Salvini, Francesco

    2013-04-01

    Faults have a (brittle) deformation zone that can be described as the presence of two distintive zones: an internal Fault core (FC) and an external Fault Damage Zone (FDZ). The FC is characterized by grinding processes that comminute the rock grains to a final grain-size distribution characterized by the prevalence of smaller grains over larger, represented by high fractal dimensions (up to 3.4). On the other hand, the FDZ is characterized by a network of fracture sets with characteristic attitudes (i.e. Riedel cleavages). This deformation pattern has important consequences on rock permeability. FC often represents hydraulic barriers, while FDZ, with its fracture connection, represents zones of higher permability. The observation of faults revealed that dimension and characteristics of FC and FDZ varies both in intensity and dimensions along them. One of the controlling factor in FC and FDZ development is the fault plane geometry. By changing its attitude, fault plane geometry locally alter the stress component produced by the fault kinematics and its combination with the bulk boundary conditions (regional stress field, fluid pressure, rocks rheology) is responsible for the development of zones of higher and lower fracture intensity with variable extension along the fault planes. Furthermore, the displacement along faults provides a cumulative deformation pattern that varies through time. The modeling of the fault evolution through time (4D modeling) is therefore required to fully describe the fracturing and therefore permeability. In this presentation we show a methodology developed to predict distribution of fracture intensity integrating seismic data and numerical modeling. Fault geometry is carefully reconstructed by interpolating stick lines from interpreted seismic sections converted to depth. The modeling is based on a mixed numerical/analytical method. Fault surface is discretized into cells with their geometric and rheological characteristics. For each cell, the acting stress and strength are computed by analytical laws (Coulomb failure). Total brittle deformation for each cell is then computed by cumulating the brittle failure values along the path of each cell belonging to one side onto the facing one. The brittle failure value is provided by the DF function, that is the difference between the computed shear and the strength of the cell at each step along its path by using the Frap in-house developed software. The width of the FC and the FDZ are computed as a function of the DF distribution and displacement around the fault. This methodology has been successfully applied to model the brittle deformation pattern of the Vignanotica normal fault (Gargano, Southern Italy) where fracture intensity is expressed by the dimensionless H/S ratio representing the ratio between the dimension and the spacing of homologous fracture sets (i.e., group of parallel fractures that can be ascribed to the same event/stage/stress field).

  13. Control of preexisting faults and near-surface diapirs on geometry and kinematics of fold-and-thrust belts (Internal Prebetic, Eastern Betic Cordillera)

    NASA Astrophysics Data System (ADS)

    Pedrera, Antonio; Marín-Lechado, Carlos; Galindo-Zaldívar, Jesús; García-Lobón, José Luis

    2014-07-01

    We have determined, for the first time, the 3D geometry of a sector of the eastern Internal Prebetic comprised between Parcent and Altea diapirs, combining structural, borehole and multichannel seismic reflection data. The tectonic structure of the Jurassic-Cretaceous carbonate series is characterized by regional ENE-WSW fold-and-thrusts that interact with oblique N-S and WNW-ESE folds, detached over Triassic evaporites and clays. The structural style comprises box-shape anticlines, and N-vergent anticlines with vertical to overturned limbs frequently bordered by reverse and strike-slip faults. The anticlines surround a triangular broad synclinal structure, the Tárbena basin, filled by a late Oligocene to Tortonian sedimentary sequence that recorded folding and thrusting history. The location and geometrical characteristics of fold-and-thrusts may be controlled by the positive inversion of pre-existing Mesozoic normal faults, and by the position and shape of near-surface diapirs composed of Triassic rocks. Therefore, we propose an initial near-surface diapir emplacement of Triassic evaporitic rocks driven by late Jurassic to early Cretaceous rifting of the southern Iberian paleomargin. Thrusting and folding started during the latest Oligocene (?28-23 Ma) roughly orthogonal to the NW-directed shortening. Deformation migrated to the south during Aquitanian (?23-20 Ma), when tectonic inversion implied the left-lateral transpressive reactivation of N-S striking former normal faults and right-lateral/reverse reactivation of inherited WNW-ESE faults. We show two mechanisms driving the extrusion of the diapirs during contraction: lateral migration of a pre-existing near-surface diapir associated with dextral transpression; and squeezing of a previous near-surface diapir at the front of an anticline. Our study underlines the value of 3D geological modeling to characterize geometry and kinematics of complex fold-and-thrust belts influenced by preexisting faults and near-surface diapirs.

  14. 3D Temperature distribution and numerical modeling of heat transfers in an active fault zone: Eugene Island 330, Offshore Louisiana.

    E-print Network

    Guerin, Gilles

    fault zone: Eugene Island 330, Offshore Louisiana. 4.1 Abstract At the center of an active growth fault system underlain by high-relief salt diapirs, the Eugene Island 330 field is a case study productive reservoirs of the EI330 oil field. #12;126 4.2 Introduction The Eugene Island 330 (EI330) oil

  15. Crustal structure and fault geometry of the 2010 Haiti earthquake from temporary seismometer deployments

    USGS Publications Warehouse

    Douilly, Roby; Haase, Jennifer S.; Ellsworth, William L.; Bouin, Marie?Paule; Calais, Eric; Symithe, Steeve J.; Armbruster, John G.; Mercier de Lépinay, Bernard; Deschamps, Anne; Mildor, Saint?Louis; Meremonte, Mark E.; Hough, Susan E.

    2013-01-01

    Haiti has been the locus of a number of large and damaging historical earthquakes. The recent 12 January 2010 Mw 7.0 earthquake affected cities that were largely unprepared, which resulted in tremendous losses. It was initially assumed that the earthquake ruptured the Enriquillo Plantain Garden fault (EPGF), a major active structure in southern Haiti, known from geodetic measurements and its geomorphic expression to be capable of producing M 7 or larger earthquakes. Global Positioning Systems (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data, however, showed that the event ruptured a previously unmapped fault, the Léogâne fault, a north?dipping oblique transpressional fault located immediately north of the EPGF. Following the earthquake, several groups installed temporary seismic stations to record aftershocks, including ocean?bottom seismometers on either side of the EPGF. We use data from the complete set of stations deployed after the event, on land and offshore, to relocate all aftershocks from 10 February to 24 June 2010, determine a 1D regional crustal velocity model, and calculate focal mechanisms. The aftershock locations from the combined dataset clearly delineate the Léogâne fault, with a geometry close to that inferred from geodetic data. Its strike and dip closely agree with the global centroid moment tensor solution of the mainshock but with a steeper dip than inferred from previous finite fault inversions. The aftershocks also delineate a structure with shallower southward dip offshore and to the west of the rupture zone, which could indicate triggered seismicity on the offshore Trois Baies reverse fault. We use first?motion focal mechanisms to clarify the relationship of the fault geometry to the triggered aftershocks.

  16. Development of kink bands in granodiorite: Effect of mechanical heterogeneities, fault geometry, and friction

    NASA Astrophysics Data System (ADS)

    Chheda, T. D.; Nevitt, J. M.; Pollard, D. D.

    2014-12-01

    The formation of monoclinal right-lateral kink bands in Lake Edison granodiorite (central Sierra Nevada, CA) is investigated through field observations and mechanics based numerical modeling. Vertical faults act as weak surfaces within the granodiorite, and vertical granodiorite slabs bounded by closely-spaced faults curve into a kink. Leucocratic dikes are observed in association with kinking. Measurements were made on maps of Hilgard, Waterfall, Trail Fork, Kip Camp (Pollard and Segall, 1983b) and Bear Creek kink bands (Martel, 1998). Outcrop scale geometric parameters such as fault length andspacing, kink angle, and dike width are used to construct a representative geometry to be used in a finite element model. Three orders of fault were classified, length = 1.8, 7.2 and 28.8 m, and spacing = 0.3, 1.2 and 3.6 m, respectively. The model faults are oriented at 25° to the direction of shortening (horizontal most compressive stress), consistent with measurements of wing crack orientations in the field area. The model also includes a vertical leucocratic dike, oriented perpendicular to the faults and with material properties consistent with aplite. Curvature of the deformed faults across the kink band was used to compare the effects of material properties, strain, and fault and dike geometry. Model results indicate that the presence of the dike, which provides a mechanical heterogeneity, is critical to kinking in these rocks. Keeping properties of the model granodiorite constant, curvature increased with decrease in yield strength and Young's modulus of the dike. Curvature increased significantly as yield strength decreased from 95 to 90 MPa, and below this threshold value, limb rotation for the kink band was restricted to the dike. Changing Poisson's ratio had no significant effect. The addition of small faults between bounding faults, decreasing fault spacing or increasing dike width increases the curvature. Increasing friction along the faults decreases slip, so the shortening is accommodated by more kinking. Analysis of these parameters also gives us an insight concerning the kilometer-scale kink band in the Mount Abbot Quadrangle, where the Rosy Finch Shear Zone may provide the mechanical heterogeneity that is necessary to cause kinking.

  17. The role of salt layers in the hangingwall deformation of kinked-planar extensional faults: Insights from 3D analogue models and comparison with the Parentis Basin

    NASA Astrophysics Data System (ADS)

    Ferrer, O.; Roca, E.; Vendeville, B. C.

    2014-12-01

    Using an analogue modelling approach, this work investigates the role played by salt in the hangingwall deformation of an extensional fault. Models' set-up included a wooden block simulating the footwall of different kinked-planar fault geometries flattening at depth. Above these faults, the hangingwall was modelled using only sand or sand overlain by pre- or syn-kinematic silicone putty. Regardless of the stage at which was deposited, the silicone appears as an efficient decoupling level that changes the deformation mode of the overlying sand layers. Above the silicone layers, the rollover panels only continue to develop up to the welding of the underlying silicone. Afterwards, they do not grow anymore and all shearing induced by the underlying fault bends is accommodated along the tilted silicone layer that acts as an extensional shear band. Further fault slip produces near-horizontal growth stratal geometries that can be easily misinterpreted as a syn-rift/post-rift boundary. In addition, the differential sedimentary loading of syn-kinematic layers triggers the upslope silicone flow from the hangingwall depocenters towards the rollover shoulders. This migration results in the formation of silicone welds at the rollover limbs and the growth of gentle silicone-cored anticlines above or near the rollover shoulder that are locally pierced by diapirs and walls. These experimental results fit with the Parentis Basin structure that, formed from the motion of lithosphere-scale kinked-planar extensional faults, includes salt inflated anticlines above their rollover shoulders and an intra-Albian unconformity interpreted now as syn-kinematic.

  18. Testing the influence of vertical, pre-existing joints on normal faulting using analogue and 3D discrete element models (DEM)

    NASA Astrophysics Data System (ADS)

    Kettermann, Michael; von Hagke, Christoph; Virgo, Simon; Urai, Janos L.

    2015-04-01

    Brittle rocks are often affected by different generations of fractures that influence each other. We study pre-existing vertical joints followed by a faulting event. Understanding the effect of these interactions on fracture/fault geometries as well as the development of dilatancy and the formation of cavities as potential fluid pathways is crucial for reservoir quality prediction and production. Our approach combines scaled analogue and numerical modeling. Using cohesive hemihydrate powder allows us to create open fractures prior to faulting. The physical models are reproduced using the ESyS-Particle discrete element Modeling Software (DEM), and different parameters are investigated. Analogue models were carried out in a manually driven deformation box (30x28x20 cm) with a 60° dipping pre-defined basement fault and 4.5 cm of displacement. To produce open joints prior to faulting, sheets of paper were mounted in the box to a depth of 5 cm at a spacing of 2.5 cm. Powder was then sieved into the box, embedding the paper almost entirely (column height of 19 cm), and the paper was removed. We tested the influence of different angles between the strike of the basement fault and the joint set (0°, 4°, 8°, 12°, 16°, 20°, and 25°). During deformation we captured structural information by time-lapse photography that allows particle imaging velocimetry analyses (PIV) to detect localized deformation at every increment of displacement. Post-mortem photogrammetry preserves the final 3-dimensional structure of the fault zone. We observe that no faults or fractures occur parallel to basement-fault strike. Secondary fractures are mostly oriented normal to primary joints. At the final stage of the experiments we analyzed semi-quantitatively the number of connected joints, number of secondary fractures, degree of segmentation (i.e. number of joints accommodating strain), damage zone width, and the map-view area fraction of open gaps. Whereas the area fraction does not change distinctly, the number of secondary fractures and connected joints increases strongly with increasing angles between basement fault and joint strike. Integrating these models with a 3-dimensional DEM code using the ESyS-Particle software allows for retrieving 4D information from the models, as well as for testing other parameters such as joint spacing or joint depth. Our DEM models are capable of robustly reproducing all characteristic features observed in the analogue models, and will provide a quantitative measure of the influence of joint-fault angle on permeability of cohesive rocks that have experienced more than one brittle deformation phase.

  19. Influence of a transverse basement fault on along-strike variations in the geometry of an inverted normal fault: Case study of the Mosha Fault, Central Alborz Range, Iran

    NASA Astrophysics Data System (ADS)

    Yassaghi, A.; Madanipour, S.

    2008-12-01

    Inverted normal faults show variations in structural geometry from footwall shortcut thrusts to hanging-wall break-back thrusts. In the present study, we evaluated along-strike variations in the geometry of the Mosha Fault, Central Alborz Range, Iran. Detailed structural mapping within the Taleqan Mountains revealed that the Mosha Fault in the eastern part of the study area is associated with a large, basement-cored hanging-wall anticline thrust over Tertiary rocks that occur as a syncline or cut by footwall shortcut thrusts. In the western part of the study area, however, the hanging wall consists of break-back thrust sheets of Paleozoic-Mesozoic rocks. These thrust sheets occur as a duplex system and have allochthonous masses gravitationally emplaced in the foothills of the Taleqan Mountains. Curved fold axial traces and scattered intrusive bodies are observed in the Valian Valley area, where the Mosha Fault is displaced across a transverse basement fault. This basement fault controlled along-strike variations in the geometry of the Mosha Fault during its evolution from a basin-bounding fault to an inverted normal fault. Inversion of the fault in the eastern part of the study area, where the fault is relatively steep, involved basement rocks; in the western part of the study area, where the fault is relatively shallowly dipping, deformation in the hanging wall is accommodated by thin-skinned break-back thrust sheets.

  20. Influence of pre-existing basement faults on the structural evolution of the Zagros Simply Folded belt: 3D numerical modelling

    NASA Astrophysics Data System (ADS)

    Ruh, Jonas B.; Gerya, Taras

    2015-04-01

    The Simply Folded Belt of the Zagros orogen is characterized by elongated fold trains symptomatically defining the geomorphology along this mountain range. The Zagros orogen results from the collision of the Arabian and the Eurasian plates. The Simply Folded Belt is located southwest of the Zagros suture zone. An up to 2 km thick salt horizon below the sedimentary sequence enables mechanical and structural detachment from the underlying Arabian basement. Nevertheless, deformation within the basement influences the structural evolution of the Simply Folded Belt. It has been shown that thrusts in form of reactivated normal faults can trigger out-of-sequence deformation within the sedimentary stratigraphy. Furthermore, deeply rooted strike-slip faults, such as the Kazerun faults between the Fars zone in the southeast and the Dezful embayment and the Izeh zone, are largely dispersing into the overlying stratigraphy, strongly influencing the tectonic evolution and mechanical behaviour. The aim of this study is to reveal the influence of basement thrusts and strike-slip faults on the structural evolution of the Simply Folded Belt depending on the occurrence of intercrustal weak horizons (Hormuz salt) and the rheology and thermal structure of the basement. Therefore, we present high-resolution 3D thermo-mechnical models with pre-existing, inversively reactivated normal faults or strike-slip faults within the basement. Numerical models are based on finite difference, marker-in-cell technique with (power-law) visco-plastic rheology accounting for brittle deformation. Preliminary results show that deep tectonic structures present in the basement may have crucial effects on the morphology and evolution of a fold-and-thrust belt above a major detachment horizon.

  1. The 3D fault and vein architecture of strike-slip releasing- and restraining bends: Evidence from volcanic-centre-relatedmineral deposits

    USGS Publications Warehouse

    Berger, B.R.

    2007-01-01

    High-temperature, volcanic-centre-related hydrothermal systems involve large fluid-flow volumes and are observed to have high discharge rates in the order of 100-400 kg/s. The flows and discharge occur predominantly on networks of critically stressed fractures. The coupling of hydrothermal fluid flow with deformation produces the volumes of veins found in epithermal mineral deposits. Owing to this coupling, veins provide information on the fault-fracture architecture in existence at the time of mineralization. They therefore provide information on the nature of deformation within fault zones, and the relations between different fault sets. The Virginia City and Goldfield mining districts, Nevada, were localized in zones of strike-slip transtension in an Early to Mid-Miocene volcanic belt along the western margin of North America. The Camp Douglas mining area occurs within the same belt, but is localized in a zone of strike-slip transpression. The vein systems in these districts record the spatial evolution of strike-slip extensional and contractional stepovers, as well as geometry of faulting in and adjacent to points along strike-slip faults where displacement has been interrupted and transferred into releasing and restraining stepovers. ?? The Geological Society of London 2007.

  2. Great Basin Center for Geothermal Energy Proposal for DOE Geothermal Funding for Research to Increase Utilization of Geothermal Resources in the Western United States 3-D Fault and Geothermal Reservoir Imaging Method Enhancement

    Microsoft Academic Search

    John Louie; Gary Oppliger

    We propose to enhance resource management and recovery efforts at existing geothermal fields by developing more accurate fault and reservoir imaging techniques for 3-d seismic surveys. Upgrading an existing parallel supercomputer facility within the Mackay School of Mines will allow us to explore the application to geothermal fields of new, computationally intensive 3-d seismic imaging methods developed by the petroleum

  3. 3D seismic interpretation in Jarn Yaphour field, Abu Dhabi

    Microsoft Academic Search

    Z. S. Z. Zeld; S. H. El Bishlawy

    1990-01-01

    A major 3D seismic project covering about 425 sq miles (1100 km²) was conducted at Jarn Yaphour to define the structural geometry, particularly faulting, better and to resolve stratigraphic complexities associated with the field's principal reservoirs. Data interpretation included detailed geoseismic mapping of nine horizons and seismostratigraphic analysis of three intervals of interest. This paper discusses the interpretation techniques applied

  4. Geometry of the San Andreas Fault and Sedimentary Basin in the Northern Salton Trough

    NASA Astrophysics Data System (ADS)

    Fuis, G. S.; Bauer, K.; Catchings, R.; Goldman, M.; Ryberg, T.; Scheirer, D. S.; Langenheim, V. E.; Rymer, M. J.; Persaud, P.; Stock, J. M.; Hole, J. A.

    2014-12-01

    The Salton Seismic Imaging Project (SSIP) was undertaken, in part, to provide more accurate information on the plate-boundary faults and basin geometry in the Salton Trough region. One of these faults, the southernmost San Andreas Fault (SAF) zone in the northern Salton Trough (Coachella Valley), is considered by many to be likely to produce a large-magnitude earthquake in the near future. We report here on the geometry of the SAF and the adjacent sedimentary basin beneath the Coachella Valley. We interpret two seismic profiles in the northern Salton Trough that are orthogonal to the axis of the Coachella Valley. Seismic imaging, potential-field studies, and (or) earthquake hypocentral relocations along these profiles indicate that the active strand of the SAF dips NE. On a southern profile, through the Mecca Hills, we obtain a reflection image of the SAF zone in the depth range of 6-12 km that coincides with the microearthquake pattern reported by Hauksson et al. (2012), dipping ~ 60° NE. Steeply dipping reflectors above 6 km emerge at the surface at mapped secondary fault traces in the Mecca Hills, clearly defining a "flower structure" for the upper SAF. On the second profile, from Palm Springs to Landers, two alternative interpretations of SAF structure are possible. By one interpretation, which is based on earthquakes alone, the Banning and Garnet Hill Faults are two closely spaced faults, dipping ~ 60° NNE that pass through two aftershock clusters of the 1986 M 5.9 North Palm Springs earthquake. By the second interpretation, which is based on our reflection imaging on this line, the Banning and Garnet Hills faults converge at 10-km depth; below that depth, a single SAF dips ~ 60° NNE. In the second interpretation, the faults above 10 km resemble the flower structure interpreted beneath the Mecca Hills on our southern profile. The deeper fault in the second interpretation is subparallel to the closely spaced faults of the first interpretation but a few km deeper. Sedimentary basin depth (Vp < 5.5 km/s, estimated) ranges from 3-4 km in the northern Coachella Valley to a maximum of 5 km in the southern Coachella Valley. Because of the generally flat magnetic field, basement beneath the Coachella Valley southwest of the SAF is interpreted to be similar to that in the Peninsular Ranges.

  5. The value of inclined coreholes for characterizing the geometry of 3-D fracture networks in bedrock aquifers

    NASA Astrophysics Data System (ADS)

    Munn, Jonathan; Parker, Beth

    2013-04-01

    In bedrock aquifers where matrix permeability is low, the nature and distribution of the fracture network has a strong impact on the transport and fate of contaminants. Accurate fracture characterization is therefore essential to fully understand the flow system and to predict contaminant migration. Powerful DFN models exist, yet the limitation is often on obtaining field data of sufficient quality to use as input parameters. One major contributing factor is the common practice of using only vertical coreholes to characterize bedrock aquifers. This can lead to datasets that are significantly biased toward fractures perpendicular to the corehole and are therefore not well suited for three-dimensional (3-D) fracture geometry characterization. This bias is particularly pronounced in flat-lying sedimentary strata where fracture networks are typically comprised of flat-lying bedding parallel fractures and vertical, or near vertical joints. An examination of such bias was conducted at a contaminated site in Guelph, Ontario, Canada, in a Silurian dolostone aquifer. Three inclined coreholes plunging 60 degrees with varying azimuths were drilled between 2010 and 2012 to supplement existing data from eleven vertical coreholes from previous investigations. Depth discrete datasets were collected in the coreholes including lithological and fracture logs from rock core, downhole geophysical surveys (e.g, acoustic televiewer, formation conductivity, temperature, natural gamma), and hydraulic testing including the first use of flexible liner profiling in inclined coreholes. These datasets were integrated to provide estimates of fracture frequency, orientation and aperture distributions and to estimate values of bulk effective fracture porosity. Orientation analysis revealed three dominant fracture sets on site that vary in intensity through mechanical layers. These sets consist of a horizontal, bedding-plane set with an average spacing of 0.3m, and two high-angle sets, NE-SW and WNW-ESE striking, with average spacings of 1.5m and 2.1m, respectively. When data from only the vertical coreholes are used for the analysis, only two fracture sets are identifiable: a bedding plane set and a high-angle E-W set, confirming the necessity of inclined coreholes for complete fracture orientation analysis. Hydraulic fracture apertures were estimated using the cubic law and range from 15 to 407 ?m with a geometric mean of 125 ?m. The fracture network properties will ultimately be used as input parameters for static and dynamic discrete fracture network models to assess current and future risks to nearby municipal supply wells. The study shows that inclined coreholes of varying orientation can help minimize sampling bias, and thereby provide a more representative sample of the fracture network.

  6. Lithological 3D grid model of the Vuonos area built by using geostatistical simulation honoring the 3D fault model and structural trends of the Outokumpu association rocks in Eastern Finland

    NASA Astrophysics Data System (ADS)

    Laine, Eevaliisa

    2015-04-01

    The Outokumpu mining district - a metallogenic province about 100 km long x 60 km wide - hosts a Palaeoproterozoic sulfide deposit characterized by an unusual lithological association. It is located in the North Karelia Schist Belt , which was thrust on the late Archaean gneissic-granitoid basement of the Karelian craton during the early stages of the Svecofennian Orogeny between 1.92 and 1.87 Ga (Koistinen 1981). Two major tectono-stratigraphic units can be distinguished, a lower, parautochthonous 'Lower Kaleva' unit and an upper, allochthonous 'upper Kaleva' unit or 'Outokumpu allochthon'. The latter consists of tightly-folded deep marine turbiditic mica schists and metagraywackes containing intercalations of black schist, and the Outo¬kumpu assemblage, which comprises ca. 1950 Ma old, serpentinized peridotites surrounded by carbonate-calc-silicate ('skarn')-quartz rocks. The ore body is enclosed in the Outokumpu assemblage, which is thought to be part of a disrupted and incomplete ophiolite complex (Vuollo & Piirainen 1989) that can be traced to the Kainuu schist belt further north where the well-preserved Jormua ophiolite is ex¬posed (Kontinen 1987, Peltonen & Kontinen 2004). Outokumpu can be divided into blocks divided by faults and shear zones (Saalmann and Laine, 2014). The aim of this study was to make a 3D lithological model of a small part of the Outokumpu association rocks in the Vuonos area honoring the 3D fault model built by Saalmann and Laine (2014). The Vuonos study area is also a part of the Outokumpu mining camp area (Aatos et al. 2013, 2014). Fault and shear structures was used in geostatistical gridding and simulation of the lithologies. Several possible realizations of the structural grids, conforming the main lithological trends were built. Accordingly, it was possible to build a 3D structural grid containing information of the distribution of the possible lithologies and an estimation the associated uncertainties. References: Aatos, S., Jokinen, J., Koistinen, E., Kontinen, A., Korhonen, J., Korpisalo, J., Kurimo, M.,Lahti, I., Laine, E., Levaniemi, H., Sorjonen-Ward, P. & Torppa, J. 2014. Developing deep exploration methods in the Outokumpu Mining Camp area. In: Lauri, L. S., Heilimo, E., Levaniemi, H., Tuusjarvi, M., Lahtinen, R. & Holtta, P. (eds) Current Research: 2nd GTK Mineral Potential Workshop, Kuopio, Finland, May 2014. Geological Survey of Finland,Report of Investigation 207. Koistinen, T. J., 1981. Structural evolution of an early Proterozoic strata-bound Cu-Co-Zn deposit, Outokumpu, Finland. Transactions of the Royal Society of Edinburgh: Earth Sciences, 72, pp. 115-158. Kontinen,A., 1987.An early Proterozoic ophiolite -- the Jormuamafic-ultramafic complex, northern Finland. Precambrian Research 35, 313-341. Peltonen, P. & Kontinen, A. 2004. The Jormua Ophiolite: a mafic-ultramafic complex from an ancient ocean-continent transition zone. In: Precambrian ophiolites and related rocks. Developments in Precambrian geology 13. Amsterdam: Elsevier, 35-71. Saalmann, K.; Laine, E.L, 2014. Structure of the Outokumpu ore district and ophiolite-hosted Cu-Co-Zn-Ni-Ag-Au sulfide deposits revealed from 3D modeling and 2D high-resolution seismic reflection data. Ore Geology Reviews, Volume 62, October 2014, Pages 156-180. Vuollo, J., and Piirainen, T., 1989. Mineralogical evidence for an ophiolite from the Outokumpu serpentinites in North Karelia, Finland. Bulletin of the Geological Society of Finland 61, 95-112.

  7. Hypocentral relocation using clustering-along-planes constraints: implications for fault geometry

    NASA Astrophysics Data System (ADS)

    Santana, Flavio L.; Medeiros, Walter E.; do Nascimento, Aderson F.; Bezerra, Francisco H. R.

    2012-08-01

    Hypocentre location is an ill-posed inverse problem even assuming that the velocity model is known, because different sets of hypocentre locations may satisfy the fitting criterion. We present a regularized hypocentre inversion in which the constraints of spatial proximity of the hypocentres to target planes are used. This constraint introduces the geological bias that earthquakes might occur along fault planes. Here, the target planes may be either (1) planes specified by the interpreter or (2) planes fitting groups of events. We assume also that initial estimates of hypocentres and origin times are available. Then, the initial hypocentre estimates, origin times and target planes are used as input to an inversion problem to relocate the hypocentres so that the maximum-possible clustering of events along the given planes is attained, matching the observed traveltimes. We use L1 norm for data fitting, L2 norm for the plane proximity criterion and a polytope algorithm to minimize the functional. Results from synthetic and real data indicate that the plane proximity constraint allows for hypocentre relocation presenting a high degree of clustering along planes. The real-data example is an intraplate earthquake sequence in NE Brazil. Our methodology defined the geometry and strike of fault segments close to known geology and focal mechanism data. In addition, the new method indicates that the fault is characterized by a splay geometry in its southern end and that more than three fault segments are necessary to explain the hypocentre distribution.

  8. Description of the Active Tectonic Deformation and Fault Friction in Iran Using Block and 3D Finite Element Modeling

    NASA Astrophysics Data System (ADS)

    Vernant, P.; Chery, J.

    2004-12-01

    The intracontinental deformation involved in the eastern part of the Arabia/Eurasia collision zone (i.e., mainly Iran) is distributed among several orogens (Zagros, Caucasus, Alborz, Kopet-Dag) surrounding rigid blocks (South Caspian, Central Iran, Lut, Helmand). In this study we investigate the more appropiated desciption of the active tectonic deformation in Iran using different modeling approaches. To do so, we have developed models of the eastern part of the Arabia/Eurasia collision ranging from eastern Turkey (~43°E) to western Afghanistan (~63°E) and from the Arabian to the Eurasian plate. The available GPS velocity fields (Vernant et al., 2004) are used to constrain (block model) or set-up the boundary conditions (finite element modeling). Two different rheologies are used for the finite element modeling: (a) one visco-elastic layer, (b) two layers: the upper one corresponds to the crust and the lower one to the lithospheric mantle. The great strike-slip faults are treated as vertical material discontinuities of the mesh. Fault slip-rates ranging from 0.3 to 0.02 are controlled by a Coulomb-type friction. A third rheology is used corresponding to the block model: (c) elastic constitutive law with fault friction = 0. The rms of the residuals (observed - modeled velocity field) are compared for the different experiments. The statistics obtained are close for the three different rheologies implying that the GPS data are too sparse to definitely conclude about the best description of the active deformation in Iran. However, elasto-plastic or elastic rheologies with law fault frictions show a slightly better fit to the GPS data. This is confirmed by the comparison between the geological fault slip rates and the modeled ones, suggesting that the active tectonic deformation in Iran can be described using rigid blocks and very low fault slip rate (0.02 to 0.0). However, more GPS measurement need to be done to conclude if the deformation is only accommodated by rigid blocks and faults or if elasto-plastic deformation zones exist somewhere in this part of the Alpine-Himalayan mountain belt.

  9. Digital Images with 3D Geometry from Data Compression by Multi-scale Representations of B-Spline Surfaces

    NASA Astrophysics Data System (ADS)

    Koch, K.

    2011-09-01

    To build up a 3D (three-dimensional) model of the surface of an object, the heights of points on the surface are measured, for instance, by a laser scanner. The intensities of the reflected laser beam of the points can be used to visualize the 3D model as range image. It is proposed here to fit a two-dimensional B-spline surface to the measured heights and intensities by the lofting method. To fully use the geometric information of the laser scanning, points on the fitted surface with their intensities are computed with a density higher than that of the measurements. This gives a 3D model of high resolution which is visualized by the intensities of the points on the B-spline surface. For a realistic view of the 3D model, the coordinates of a digital photo of the object are transformed to the coordinate system of the 3D model so that the points get the colors of the digital image. To efficiently compute and store the 3D model, data compression is applied. It is derived from the multi-scale representation of the dense grid of points on the B-spline surface. The proposed method is demonstrated for an example.

  10. Geometry and kinematics of the Mosha Fault, south central Alborz Range, Iran: An example of basement involved thrusting

    NASA Astrophysics Data System (ADS)

    Moinabadi, Mohsen Ehteshami; Yassaghi, Ali

    2007-03-01

    Field investigation of the western part of the Mosha Fault in several structural sections in the south central Alborz Range showed that the fault has a high angle of dip to the north, and emplaces Precambrian to Cenozoic rocks over the Eocene Karaj Formation. Study of the kinematics of the Mosha Fault in this area, based on S-C fabric and microstructures, demonstrates that it is a deep-seated semi-ductile thrust. Strain analysis on rock samples from different sections across the Mosha Fault shows a flattening pattern of deformation in which the long axis of the strain ellipsoid is aligned in the fault shear sense. The Mosha Fault is associated with a large hanging-wall anticline, cored by Precambrian rocks, and series of footwall synclines, formed of late Tertiary rocks. This geometry, together with several low angle short-cut thrusts in the fault footwall, implies that the Mosha Fault is an inverted normal fault which has been reactivated since the late Tertiary. In the study area, the reverse fault mechanism was associated with the rapid uplift and igneous activity in the central Alborz Range during the late Tertiary, unlike in the eastern portion of the fault, where the fault kinematics was replaced by a strike-slip mechanism in the Late Miocene.

  11. Geodetic imaging of potential seismogenic asperities on the Xianshuihe-Anninghe-Zemuhe fault system, southwest China, with a new 3-D viscoelastic interseismic coupling model

    NASA Astrophysics Data System (ADS)

    Jiang, Guoyan; Xu, Xiwei; Chen, Guihua; Liu, Yajing; Fukahata, Yukitoshi; Wang, Hua; Yu, Guihua; Tan, Xibin; Xu, Caijun

    2015-03-01

    We use GPS and interferometric synthetic aperture radar (InSAR) measurements to image the spatial variation of interseismic coupling on the Xianshuihe-Anninghe-Zemuhe (XAZ) fault system. A new 3-D viscoelastic interseismic deformation model is developed to infer the rotation and strain rates of blocks, postseismic viscoelastic relaxation, and interseismic slip deficit on the fault surface discretized with triangular dislocation patches. The inversions of synthetic data show that the optimal weight ratio and smoothing factor are both 1. The successive joint inversions of geodetic data with different viscosities reveal six potential fully coupled asperities on the XAZ fault system. Among them, the potential asperity between Shimian and Mianning, which does not exist in the case of 1019 Pa s, is confirmed by the published microearthquake depth profile. Besides, there is another potential partially coupled asperity between Daofu and Kangding with a length scale up to 140 km. All these asperity sizes are larger than the minimum resolvable wavelength. The minimum and maximum slip deficit rates near the Moxi town are 7.0 and 12.7 mm/yr, respectively. Different viscosities have little influence on the roughness of the slip deficit rate distribution and the fitting residuals, which probably suggests that our observations cannot provide a good constraint on the viscosity of the middle lower crust. The calculation of seismic moment accumulation on each segment indicates that the Songlinkou-Selaha (S4), Shimian-Mianning (S7), and Mianning-Xichang (S8) segments are very close to the rupture of characteristic earthquakes. However, the confidence level is confined by sparse near-fault observations.

  12. Geometry

    NSDL National Science Digital Library

    Mr. Edwards

    2010-09-29

    Geometric concepts Thanks to all who have contributed to this site. Your hard work is appreciated. Geogebra Interactive manipulation of geometric figures National Library of Virtual Manipulatives Utah State University internet site with lots of math games Pythagorean Theorem Find out how the Greek philosopher figured the lengths of lines in a right triangle Triangles Build, name and see triangles in 3-D Great Geometry Play a matching game with polygons Learn to sort the different types of triangles Groovy Geometry Make different shapes and sizes ...

  13. 3D model of fault and fissures structure of the Kovdor Baddeleyite-Apatite-Magnetite Deposit (NE of the Fennoscandian Shield)

    NASA Astrophysics Data System (ADS)

    Zhirov, Dmitry; Klimov, Sergey

    2015-04-01

    The Kovdor baddeleyite-apatite-magnetite deposit (KBAMD) is represented by a large vertical ore body and is located in the southwestern part of the Kovdor ultramafic-alkaline central-type intrusion. The intrusion represents a concentrically zoned complex of rocks with an oval shape in plan, and straight zoning, which complies with the injection and displacement of each of further magma phases from the center towards the periphery. The operation of the deposit in open pits started in 1962, and nowadays, it has produced over 500,000,000 tons of ore. This is one of the largest open pits in the Kola region, which is ca. 2 km long, 1.8 km wide, and over 400 m deep. Regular structural studies has been carried out since late 1970. A unique massif of spatial data has been accumulated so far to include over 25,000 measurements of fissures and faults from the surface, ca. 20,000 measurements of fissures in the oriented drill core (over 18 km) etc. Using this data base the 3D model of fault and fissures structure was designed. The analysis of one has resulted in the identification of a series of laws and features, which are necessary to be taken into account when designing a deep open pit and mining is carried out. These are mainly aspects concerning the origin, kinematics, mechanics and ratio of spatial extension of various fault systems, variation of their parameters at deep horizons, features of a modern stress field in the country rocks, etc. The 3D model has allowed to divide the whole fracture / fissure systems of the massif rocks into 2 large groups: prototectonic system of joints, including cracks of 'liquid magmatic (carbonatite stage) contraction genesis', and newly formed faults due to the superimposed tectonic stages. With regard to the deposit scale, these are characterized as intraformational and transformational, respectively. Each group shows a set (an assemblage) of fault systems with unique features and signs, as well as regular interconnections. The prototectonic assemblage of fissures includes the following main systems: 2-3 subsystems Rd of radial with angle of dip within 65-90° (median at 78°), two subsystems S of a circular subvertical (tangential, crossing Rd) with angle of dip within 60-90° (74°), and two diagonal-conic ones: a centriclinal C dipping towards the center of the intrusion at angles of 25-55° (43°), and a periclinal P dipping from the center of the intrusion at angles of 5-35° (18°). The system of subhorizontal joints L (angle of dip within 0-12°) at deep horizons is insignificantly manifested. All the prototectonic systems are regularly interrelated, and vary asymuthal features according to the law of axial symmetry (when moving around the vertical axis of symmetry passed through the geometric center of the carbonatite intrusion). The superimposed tectonics of post-ore stages forms a few large faults and systems of rupture discontinuities. A few (up to 3) variously oriented displacements are documented in the field on kinematic features (slide furrows, oriented cleavages). They were used for reconstruction of stresses and tectonic evolution. The superimposed tectonic faulting has heterogeneous (local) distribution in the rocks of the deposit, and slight predictability of main parameters. This study was supported by the Russian Scientific Fund (project nos. 14-17-00751).

  14. R2OBBIE-3D, a Fast Robotic High-Resolution System for Quantitative Phenotyping of Surface Geometry and Colour-Texture.

    PubMed

    Martins, António F; Bessant, Michel; Manukyan, Liana; Milinkovitch, Michel C

    2015-01-01

    While recent imaging techniques provide insights into biological processes from the molecular to the cellular scale, phenotypes at larger scales remain poorly amenable to quantitative analyses. For example, investigations of the biophysical mechanisms generating skin morphological complexity and diversity would greatly benefit from 3D geometry and colour-texture reconstructions. Here, we report on R2OBBIE-3D, an integrated system that combines a robotic arm, a high-resolution digital colour camera, an illumination basket of high-intensity light-emitting diodes and state-of-the-art 3D-reconstruction approaches. We demonstrate that R2OBBIE generates accurate 3D models of biological objects between 1 and 100 cm, makes multiview photometric stereo scanning possible in practical processing times, and enables the capture of colour-texture and geometric resolutions better than 15 ?m without the use of magnifying lenses. R2OBBIE has the potential to greatly improve quantitative analyses of phenotypes in addition to providing multiple new applications in, e.g., biomedical science. PMID:26039509

  15. R2OBBIE-3D, a Fast Robotic High-Resolution System for Quantitative Phenotyping of Surface Geometry and Colour-Texture

    PubMed Central

    Manukyan, Liana; Milinkovitch, Michel C.

    2015-01-01

    While recent imaging techniques provide insights into biological processes from the molecular to the cellular scale, phenotypes at larger scales remain poorly amenable to quantitative analyses. For example, investigations of the biophysical mechanisms generating skin morphological complexity and diversity would greatly benefit from 3D geometry and colour-texture reconstructions. Here, we report on R2OBBIE-3D, an integrated system that combines a robotic arm, a high-resolution digital colour camera, an illumination basket of high-intensity light-emitting diodes and state-of-the-art 3D-reconstruction approaches. We demonstrate that R2OBBIE generates accurate 3D models of biological objects between 1 and 100 cm, makes multiview photometric stereo scanning possible in practical processing times, and enables the capture of colour-texture and geometric resolutions better than 15 ?m without the use of magnifying lenses. R2OBBIE has the potential to greatly improve quantitative analyses of phenotypes in addition to providing multiple new applications in, e.g., biomedical science. PMID:26039509

  16. Geometry and faults tectonic activity of the Okavango Rift Zone, Botswana: Evidence from magnetotelluric and electrical resistivity tomography imaging

    NASA Astrophysics Data System (ADS)

    Bufford, Kelsey Mosley; Atekwana, Estella A.; Abdelsalam, Mohamed G.; Shemang, Elijah; Atekwana, Eliot A.; Mickus, Kevin; Moidaki, Moikwathai; Modisi, Motsoptse P.; Molwalefhe, Loago

    2012-04-01

    We used Magnetotelluric (MT) and Electrical Resistivity Tomography (ERT) to investigate the geometry and nature of faults activity of the Okavango Rift Zone (ORZ) in Botswana, an incipient rift at the southern tip of the Southwestern Branch of the East African Rift System. The ORZ forms a subtle topographic depression filled with Quaternary lacustrine and fluvio-deltaic sediments and is bounded by NE-trending normal faults that are more prominent in the southeastern portion of the rift basin. An MT model from a regional (˜140 km) NW-SE trending MT transect shows that much of the rift basin is underlain by a broad asymmetrical low resistivity anomaly that slopes gently (˜1°) from NW to SE reaching a depth of ˜300 m. This anomaly suggests that faults in the southeastern part of the rift form a NW-dipping border fault zone and that the lacustrine and fluvio-deltaic sediments contain brackish to saline water filling the broad half-graben structure. Furthermore, MT and ERT models from detailed (4-13 km long) MT transects and resistivity profiles show that one border fault (Thamalakane) and two within-basin faults (Lecha and Tsau) in the southeastern part of the ORZ are characterized by a localized high conductivity anomaly while another border fault (Kunyere) lacks such an anomaly. These localized anomalies are attributed to channelized fresh surface water and saline groundwater percolating through these faults forming "fault zone conductors" and suggest actively displacing faults. The lack of a "fault zone conductor" in the Kunyere fault is interpreted as indicating diminishing displacement on this fault, and that strain was transferred to the Thamalakane fault further to the east. The fluids provide lubricant for the ORZ faults, hence preventing infrequent large magnitude earthquakes, but favoring frequent micro-seismicity.

  17. Relocation of the microseismicity in the Corinth rift and implications on the faulting geometry

    NASA Astrophysics Data System (ADS)

    Pacchiani, F.; Lyon-Caen, H.; Bourouis, S.; Bernard, P.; Deschamps, A.; Papadimitriou, P.; Makropoulos, K.

    2003-04-01

    We present the relocation results of the microseismicity associated with the Corinth Rift in the region of the city of Aigion, Greece. The data used were recorded by a permanent network of 12 stations, in an area of 30km x 30km around the city of Aigion, which started recording in May 2000. Nearly 5000 events have been located since, including the ML = 4.7 earthquake of April 8, 2001. The seismic activity is characterized by clusters of different sizes that are located in a thin and shallow seismogenic zone mainly between 4km and 10km of depth accompanied by diffuse seismicity which is more important to the north. The microseismicity of the region is relocated putting emphasis on the most important clusters. The latter are identified by comparing wavelet transforms of the signals. The P- and S-wave travel-times for the clustered events are corrected using cross-spectral correlations. Two relocation methods are employed: a master-slave event based method and the double-difference algorithm, HYPODD. In an attempt to constrain the geometry of the underlying faults, we computed the poles of all possible 3-point planes within a cluster, each hypocenter being a point. We will present the geometry of each cluster in relationship with the geometry of the faults and discuss the implications for the active deformation of the rift. For the principal cluster related to the April 8, 2001 earthquake, the preferred plane varies. However, there is a prevailing plane orientation which strikes between 210 and 240 degrees and dips between 30 and 60 degrees. This result is in agreement with the focal mechanism of the mainshock (Zahradnik et al. 2003, submitted) and with the regional stress state. The orientation of the plane is not related to observed structures in the field and is most probably associated to re-activation of pre-existing faults.

  18. Reorienting in Virtual 3D Environments: Do Adult Humans Use Principal Axes, Medial Axes or Local Geometry?

    PubMed Central

    Ambosta, Althea H.; Reichert, James F.; Kelly, Debbie M.

    2013-01-01

    Studies have shown that animals, including humans, use the geometric properties of environments to orient. It has been proposed that orientation is accomplished primarily by encoding the principal axes (i.e., global geometry) of an environment. However, recent research has shown that animals use local information such as wall length and corner angles as well as local shape parameters (i.e., medial axes) to orient. The goal of the current study was to determine whether adult humans reorient according to global geometry based on principal axes or whether reliance is on local geometry such as wall length and sense information or medial axes. Using a virtual environment task, participants were trained to select a response box located at one of two geometrically identical corners within a featureless rectangular-shaped environment. Participants were subsequently tested in a transformed L-shaped environment that allowed for a dissociation of strategies based on principal axes, medial axes and local geometry. Results showed that participants relied primarily on a medial axes strategy to reorient in the L-shaped test environment. Importantly, the search behaviour of participants could not be explained by a principal axes-based strategy. PMID:24223869

  19. Orogen-parallel variability in 3D seismicity distribution, Northern Apennines (Italy): Evidence for a slab tear fault?

    NASA Astrophysics Data System (ADS)

    Piccinini, D.; Piana Agostinetti, N.; Saccorotti, G.; Fiaschi, A.; Matassoni, L.; Morelli, M.

    2014-12-01

    Within the central Mediterranean geodynamic puzzle, the seismotectonic processes of the northern sector of the Apennines are still under debate. In this framework, we conducted a careful examination of seismic catalogues for five years of instrumental seismicity located in the eastern sector of the Tosco-Emiliano Apennines. In our study, we merge two separate seismic bulletins, derived from a small- and a large-aperture seismic network. The joint analysis of the seismic phases of both catalogues allows us to improve event locations and to assess their hypocentral depths. After re-location using a regional velocity model, we found that the spatial distribution of hypocenters follows characteristic patterns at the southwestern and northeastern sides of the chain. Such distribution exhibits a marked axial offset in correspondence of the Livorno-Sillaro Line (LSL), a NE-SW trending lithological discontinuity previously interpreted in terms of a transform zone. Basing on this evidence, and on additional observations related to the morphology of the area, we hypothesise the LSL to represent the shallow manifestation of a discontinuity affecting the whole lithospheric thickness, i.e. a incipient tear fault dislocating the subducting slab.

  20. FACET: a radiation view factor computer code for axisymmetric, 2D planar, and 3D geometries with shadowing

    SciTech Connect

    Shapiro, A.B.

    1983-08-01

    The computer code FACET calculates the radiation geometric view factor (alternatively called shape factor, angle factor, or configuration factor) between surfaces for axisymmetric, two-dimensional planar and three-dimensional geometries with interposed third surface obstructions. FACET was developed to calculate view factors for input to finite-element heat-transfer analysis codes. The first section of this report is a brief review of previous radiation-view-factor computer codes. The second section presents the defining integral equation for the geometric view factor between two surfaces and the assumptions made in its derivation. Also in this section are the numerical algorithms used to integrate this equation for the various geometries. The third section presents the algorithms used to detect self-shadowing and third-surface shadowing between the two surfaces for which a view factor is being calculated. The fourth section provides a user's input guide followed by several example problems.

  1. Structure Segmentation and Transfer Faults in the Marcellus Shale, Clearfield County, Pennsylvania: Implications for Gas Recovery Efficiency and Risk Assessment Using 3D Seismic Attribute Analysis

    NASA Astrophysics Data System (ADS)

    Roberts, Emily D.

    The Marcellus Shale has become an important unconventional gas reservoir in the oil and gas industry. Fractures within this organic-rich black shale serve as an important component of porosity and permeability useful in enhancing production. Horizontal drilling is the primary approach for extracting hydrocarbons in the Marcellus Shale. Typically, wells are drilled perpendicular to natural fractures in an attempt to intersect fractures for effective hydraulic stimulation. If the fractures are contained within the shale, then hydraulic fracturing can enhance permeability by further breaking the already weakened rock. However, natural fractures can affect hydraulic stimulations by absorbing and/or redirecting the energy away from the wellbore, causing a decreased efficiency in gas recovery, as has been the case for the Clearfield County, Pennsylvania study area. Estimating appropriate distances away from faults and fractures, which may limit hydrocarbon recovery, is essential to reducing the risk of injection fluid migration along these faults. In an attempt to mitigate the negative influences of natural fractures on hydrocarbon extraction within the Marcellus Shale, fractures were analyzed through the aid of both traditional and advanced seismic attributes including variance, curvature, ant tracking, and waveform model regression. Through the integration of well log interpretations and seismic data, a detailed assessment of structural discontinuities that may decrease the recovery efficiency of hydrocarbons was conducted. High-quality 3D seismic data in Central Pennsylvania show regional folds and thrusts above the major detachment interval of the Salina Salt. In addition to the regional detachment folds and thrusts, cross-regional, northwest-trending lineaments were mapped. These lineaments may pose a threat to hydrocarbon productivity and recovery efficiency due to faults and fractures acting as paths of least resistance for induced hydraulic stimulation fluids. These lineaments may represent major transfer faults that serve as pathways for hydraulic fluid migration. Detection and evaluation of fracture orientation and intensity and emphasis on the relationship between fracture intensity and production potential is of high interest in the study area as it entails significant time and cost implications for both conventional and unconventional hydrocarbon exploration and production.

  2. Rupture behavior and ground motion from 3D simulations of the Casa Loma - Claremont stepover on the San Jacinto Fault, southern California

    NASA Astrophysics Data System (ADS)

    Lozos, J.; Oglesby, D. D.; Brune, J. N.; Olsen, K. B.

    2011-12-01

    The extensional stepover between the Claremont and Casa Loma strands of the San Jacinto Fault in southern California is an area in which complex fault geometry may have a controlling effect on both rupture propagation and ground motion. The two main strands of the fault in this region are roughly parallel, with an average 4 km separation between them, but smaller complexities within the individual strands may affect rupture velocity, slip rate, seismic radiation, and ground motion. The presence of the Farm Road strand, a smaller fault segment between the Claremont and Casa Loma strands, may add further complexity to the rupture behavior. We use the three-dimensional finite element method to conduct models of this complex stepover region. We test several different nucleation locations, several initial stress states, and several different seismogenic depths for the Farm Road strand. We then use the outputs of these dynamic models to determine ground motion distributions from these ruptures. We find that the nucleation location strongly affects the rupture's ability to jump the stepover; nucleations closer to the overlap are less likely to result in jumping rupture. Including the Farm Road strand makes a considerable difference in the rupture behavior and ground motion distribution when compared to a model without it, though its contribution is complex. The strength of its effect is variable based on nucleation location, and while its presence does allow rupture to jump the larger stepover in stress states that would normally prohibit jumping, it serves to reduce radiated energy and ground motion in stress states that would allow rupture to jump in the absence of the smaller strand. The depth of the Farm Road strand has more effect on the rupture in the stress state that would not permit jumping in the absence of that segment. These results suggest that hazard associated with rupture on the northern San Jacinto depends on specific nucleation point, but also that a seemingly less-permissive stress state for throughgoing rupture may ultimately lead to stronger ground motions. This work also continues to highlight the non-monotonic effects of an intermediate fault segment on rupture behavior through a larger stepover.

  3. Dynamical System Analysis and Forecasting of Deformation Produced by an Earthquake Fault

    Microsoft Academic Search

    Marian Anghel; Yehuda Ben-Zion; Ramiro Rico-Martinez

    2004-01-01

    — We present a method of constructing low-dimensional nonlinear models describing the main dynamical features of a discrete 2-D cellular fault zone, with many degrees of freedom, embedded in a 3-D elastic solid. A given fault system is characterized by a set of parameters that describe the dynamics, rheology, property disorder, and fault geometry. Depending on the location in the

  4. Modelling of bubbly and annular two-phase flow in subchannel geometries with BACCHUS-3D/TP

    SciTech Connect

    Bottoni, M.; Lyczkowski, R.W.

    1992-01-01

    The theoretical and computational bases of the BACCHUS-3D/TP computer program are reviewed. The computer program is used for thermal-hydraulic analyses of nuclear fuel bundles under normal and accident conditions. The present program combines two models and solution procedures previously used separately, namely, the Improved Slip Model (ISM) and the Separated-Phases Model (SPM). The former model uses mixture equations with accounting for slip between the phases, whereas the latter uses separate continuity and momentum equations. At the present stage of development, both assume thermodynamic equilibrium. Techniques used to affect smooth transition between the two models are described. including treatment of frictional pressure drop and solution of the Poisson and momentum equations. A detailed derivation of the computation of mass transfer between the phases is given because it is a central and novel feature of the model.

  5. Constraints on recent earthquake source parameters, fault geometry and aftershock characteristics in Oklahoma

    NASA Astrophysics Data System (ADS)

    McNamara, D. E.; Benz, H.; Herrmann, R. B.; Bergman, E. A.; McMahon, N. D.; Aster, R. C.

    2014-12-01

    In late 2009, the seismicity of Oklahoma increased dramatically. The largest of these earthquakes was a series of three damaging events (Mw 4.8, 5.6, 4.8) that occurred over a span of four days in November 2011 near the town of Prague in central Oklahoma. Studies suggest that these earthquakes were induced by reactivation of the Wilzetta fault due to the disposal of waste water from hydraulic fracturing ("fracking") and other oil and gas activities. The Wilzetta fault is a northeast trending vertical strike-slip fault that is a well known structural trap for oil and gas. Since the November 2011 Prague sequence, thousands of small to moderate (M2-M4) earthquakes have occurred throughout central Oklahoma. The most active regions are located near the towns of Stillwater and Medford in north-central Oklahoma, and Guthrie, Langston and Jones near Oklahoma City. The USGS, in collaboration with the Oklahoma Geological Survey and the University of Oklahoma, has responded by deploying numerous temporary seismic stations in the region in order to record the vigorous aftershock sequences. In this study we use data from the temporary seismic stations to re-locate all Oklahoma earthquakes in the USGS National Earthquake Information Center catalog using a multiple-event approach known as hypo-centroidal decomposition that locates earthquakes with decreased uncertainty relative to one another. Modeling from this study allows us to constrain the detailed geometry of the reactivated faults, as well as source parameters (focal mechanisms, stress drop, rupture length) for the larger earthquakes. Preliminary results from the November 2011 Prague sequence suggest that subsurface rupture lengths of the largest earthquakes are anomalously long with very low stress drop. We also observe very high Q (~1000 at 1 Hz) that explains the large felt areas and we find relatively low b-value and a rapid decay of aftershocks.

  6. Geophysical Investigation of the Offshore Section of the Northern San Andreas Fault: Fault Zone Geometries, Shallow Deformation Patterns, and Holocene Sediment Distribution

    NASA Astrophysics Data System (ADS)

    Beeson, J. W.; Goldfinger, C.; Johnson, S. Y.

    2014-12-01

    We mapped a ~120 km offshore section of the northern San Andreas Fault (NSAF) between Pt. Arena and Pt. Delgada using closely spaced seismic-reflection profiles, high-resolution multibeam bathymetry and marine magnetics data. This new dataset documents NSAF location and continuity, associated tectonic geomorphology, shallow stratigraphy and deformation. Variable deformation patterns in the generally narrow (~1-km-wide) fault zone are largely associated with fault trend and fault bends. We have described four regions (Pt. Arena, Basin, Shelter Cove, and Mendocino) along and adjacent to the NSAF based on fault trend, deformation styles, seismic stratigraphy, and seafloor bathymetry. The NSAF in the southern region (Pt. Arena) of the survey area is imaged as an arcuate fault trace that changes ~15° (327° to 342°) from south to north over a distance of about 50 km. The NSAF in the middle two regions (Basin and Shelter Cove) passes through two acute fault bends (~9° and ~8°), resulting in both an asymmetric "lazy z" sedimentary basin and an uplifted rocky shoal ("Tolo Bank"). The northwestern region of the survey area (Mendocino) lies west of the NSAF and Shelter Cove, and includes an east-trending fault zone related to the Mendocino transform fault that extends onshore near Punta Gorda. Using the densely spaced seismic-reflection profiles we have created an isopach map of Holocene sediment throughout the survey area. This isopach map has revealed thick sediment piles adjacent to coastal watersheds with high uplift rates. We infer from fault geometries, local bathymetry/topography and aero/marine magnetics that the NSAF zone transitions from a broadly distributed fault zone to a narrow fault zone over a short distance near Shelter Cove, Ca. At Shelter Cove the NSAF is characterized as a narrow, continuous fault. North of Shelter Cove the San Andreas likely terminates into a series of "horse tail" splay thrust faults known as the Kings Range Thrust. These observations allows for the NSAF near Shelter Cove, CA to accommodate significant slip, in agreement with paleoseismic studies and historical records.

  7. Marrow-derived stem cell motility in 3D synthetic scaffold is governed by geometry along with adhesivity and stiffness.

    PubMed

    Peyton, Shelly R; Kalcioglu, Z Ilke; Cohen, Joshua C; Runkle, Anne P; Van Vliet, Krystyn J; Lauffenburger, Douglas A; Griffith, Linda G

    2011-05-01

    Design of 3D scaffolds that can facilitate proper survival, proliferation, and differentiation of progenitor cells is a challenge for clinical applications involving large connective tissue defects. Cell migration within such scaffolds is a critical process governing tissue integration. Here, we examine effects of scaffold pore diameter, in concert with matrix stiffness and adhesivity, as independently tunable parameters that govern marrow-derived stem cell motility. We adopted an "inverse opal" processing technique to create synthetic scaffolds by crosslinking poly(ethylene glycol) at different densities (controlling matrix elastic moduli or stiffness) and small doses of a heterobifunctional monomer (controlling matrix adhesivity) around templating beads of different radii. As pore diameter was varied from 7 to 17?µm (i.e., from significantly smaller than the spherical cell diameter to approximately cell diameter), it displayed a profound effect on migration of these stem cells-including the degree to which motility was sensitive to changes in matrix stiffness and adhesivity. Surprisingly, the highest probability for substantive cell movement through pores was observed for an intermediate pore diameter, rather than the largest pore diameter, which exceeded cell diameter. The relationships between migration speed, displacement, and total path length were found to depend strongly on pore diameter. We attribute this dependence to convolution of pore diameter and void chamber diameter, yielding different geometric environments experienced by the cells within. PMID:21449030

  8. Marrow-Derived Stem Cell Motility in 3D Synthetic Scaffold Is Governed by Geometry Along With Adhesivity and Stiffness

    PubMed Central

    Peyton, Shelly R.; Kalcioglu, Z. Ilke; Cohen, Joshua C.; Runkle, Anne P.; Van Vliet, Krystyn J.; Lauffenburger, Douglas A.

    2012-01-01

    Design of 3D scaffolds that can facilitate proper survival, proliferation, and differentiation of progenitor cells is a challenge for clinical applications involving large connective tissue defects. Cell migration within such scaffolds is a critical process governing tissue integration. Here, we examine effects of scaffold pore diameter, in concert with matrix stiffness and adhesivity, as independently tunable parameters that govern marrow-derived stem cell motility. We adopted an “inverse opal” processing technique to create synthetic scaffolds by crosslinking poly(ethylene glycol) at different densities (controlling matrix elastic moduli or stiffness) and small doses of a heterobifunctional monomer (controlling matrix adhesivity) around templating beads of different radii. As pore diameter was varied from 7 to 17 µm (i.e., from significantly smaller than the spherical cell diameter to approximately cell diameter), it displayed a profound effect on migration of these stem cells—including the degree to which motility was sensitive to changes in matrix stiffness and adhesivity. Surprisingly, the highest probability for substantive cell movement through pores was observed for an intermediate pore diameter, rather than the largest pore diameter, which exceeded cell diameter. The relationships between migration speed, displacement, and total path length were found to depend strongly on pore diameter. We attribute this dependence to convolution of pore diameter and void chamber diameter, yielding different geometric environments experienced by the cells within. PMID:21449030

  9. Self-organizing fault systems and self-organizing elastodynamic events on them: Geometry and the distribution of sizes of events

    E-print Network

    Shaw, Bruce E.

    Self-organizing fault systems and self-organizing elastodynamic events on them: Geometry. [1] We introduce a new model which both generates a self- organizing complex segmented fault system fault system. This opens up a new realm of study of populations of cascading elastodynamic ruptures

  10. Temporal variation in the geometry of a strike slip fault zone: Examples from the Dead Sea Transform

    NASA Astrophysics Data System (ADS)

    Marco, Shmuel

    2007-12-01

    The location of the active fault strands along the Dead Sea Transform fault zone (DST) changed through time. In the western margins of Dead Sea basin, the early activity began a few kilometers west of the preset shores and moved toward the center of the basin in four stages. Similar centerward migration of faulting is apparent in the Hula Valley north of the Sea of Galilee as well as in the Negev and the Sinai Peninsula. In the Arava Valley, seismic surveys reveal a series of buried inactive basins whereas the current active strand is on their eastern margins. In the central Arava the centerward migration of activity was followed by outward migration with Pleistocene faulting along NNE-trending faults nearly 50 km west of the center. Largely the faulting along the DST, which began in the early-middle Miocene over a wide zone of up to 50 km, became localized by the end of the Miocene. The subsidence of fault-controlled basins, which were active in the early stage, stopped at the end of the Miocene. Later during the Plio-Pleistocene new faults were formed in the Negev west of the main transform. They indicate that another cycle has begun with the widening of the fault zone. It is suggested that the localization of faulting goes on as long as there is no change in the stress field. The stresses change because the geometry of the plates must change as they move, and consequently the localization stage ends. The fault zone is rearranged, becomes wide, and a new localization stage begins as slip accumulates. It is hypothesized that alternating periods of widening and narrowing correlate to changes of the plate boundaries, manifest in different Euler poles.

  11. Timing and geometry of left-slip faulting and compressional folding in Hondo Field, Western Santa Barbara Channel

    SciTech Connect

    McGroder, M. (Exxon Production Research Co., Houston, TX (United States)); Millson, C.; Gardner, D. (Exxon Co., Thousand Oaks, CA (United States))

    1994-04-01

    Hondo field is located within the Santa Ynez offshore lease unit, approximately 5 mi south of Gaviota, California. Production is from Monterey fractured shales and deeper sandstone horizons. Two types of structures are well imaged on 3-D reflection data from the east end of the field, which has undergone 3-D prestack time migration. The most conspicuous structure is an east-west compressional fold with a gently to moderately dipping southern limb and a shorter and more steeply dipping north limb. The shape of the fold suggests that uplift was related to southward transport up a north dipping thrust ramp at (subseismic) depth. The northern limb of this structure is widest at the level of the top Sisquoc Formation and narrowest in sediments 2-3 cycles beneath the sea floor. This triangular panel of north dip indicates growth of the structure commenced during deposition of the lower Pico Formation in the Pliocene, and continued through the Pleistocene. The second-order structures that control trap distribution within the field include high-angle faults that trend roughly eastwest. The northernmost of these faults, the north bounding fault (NBF) is known from well data to have 1500 feet of throw and to dip steeply to the south. It would restore to a vertical or steep north dip upon removal of the effects of Pliocene-Pleictocene folding. The southernmost of these faults (SF) appears to change displacement from down-to-the-south in the east to down-to-the-north in the west and also dips steeply. A high-angle fault in the center of the field (CF) also has a variable sense of offset across it. Several prominent northeast-southwest faults lie between the CF and SF and clearly exhibit normal separation on vertical time sections and left separation on time slices. Variable thicknesses of Sisquoc Formation and roughly uniform thicknesses on Monterey Formation indicate that these faults were active in latest Miocene to early Pliocene.

  12. P1 approximation, MDA and IDA for the simulation of radiative transfer in a 3D geometry for an absorbing scattering medium

    NASA Astrophysics Data System (ADS)

    Gerardin, J.; Seiler, N.; Ruyer, P.; Trovalet, L.; Boulet, P.

    2012-01-01

    A numerical study has been conducted using the differential approximation and two modified versions of this method, known as MDA and IDA. The methods have been applied on a 3D geometry containing a participating, absorbing, emitting and anisotropically scattering medium. Comparisons have been carried out with some cases of the literature. It has been observed that the IDA can significantly improve the solution, where the classical P1 approximation is not able to reproduce accurately the actual flux or flux divergence in some of studied configurations. The MDA does not really improve the solution in the purely absorbing cases and when radiation is mainly coming from the medium. In other situations (scattering media, relevant influence of the boundaries), the MDA is more accurate than the P1 but the IDA still performs better, with uncertainties around a few percents for the literature cases studied in the present work.

  13. Geometry of basement faults around the Soultz geothermal wells from reflected and converted seismic waves recorded during the 2007 multisource VSP survey

    NASA Astrophysics Data System (ADS)

    Lubrano Lavadera, P.; Marthelot, J.; Zillmer, M.; Cornet, F. H.; Genter, A.

    2012-12-01

    Three wells (GPK 2 to 4) drilled at the Soultz geothermal site (France) penetrate the granitic basement of the Rhine graben between 1.5 and 5 km depth where the temperature at TD is 200°C. They are located at a distance of 5 km from the western southeast-dipping border fault of the graben in an area where the sedimentary cover is affected by a network of antithetic normal faults having local strikes in a fan of +/-30° relative to the North. The wells are deviated beneath 2.5 km with a maximum lateral offset of 0.6 km between wells. A VSP (Vertical Seismic Profiling) survey has been conducted in 2007 with 3 component geophones placed at 20 m interval between depths of 3 to 5 km in the GPK 3 and 4 wells and a vertical vibrator located at 26 surface positions spread at distances between 500m and 5km from the well head in different azimuths. After correlation with the 8 to 88 Hz vibrator sweep, the different seismic waves are separated according to their apparent velocities across the geophone lines for each shot position and each well. The downgoing waves include P and S wave trains having the slopes of the direct P and S waves in the granite. After f-k filtering of these large amplitude waves, coherent downgoing arrivals with apparent velocities larger than the direct P waves appear on vertical and horizontal geophone components. In contrast to VSP in stratified sediments, upgoing waves are absent or restricted to a small depth interval in the vicinity of P wave first arrivals. The traveltimes of direct P waves correspond to a model with P wave velocities increasing from 2 to 4.6 km/s in the 1.5 km thick sedimentary cover and 6 km/s in the granite. A previous 3D model of fracture zone indicators at different scales within the reservoir (cores, image and flow logs, induced microseismicity patterns) has led to the tentative identification of a major NNW trending 70° dipping basement fault intersecting the GPK3 well at 4775 m measured depth. 3D ray tracing of P waves reflected on this fault and recorded in the two wells provides traveltimes that fit the high apparent velocity downgoing waves for the shots located in positions allowing reflections. Depending on the incidence angles of the reflected waves at the geophones, these waves are observed in a complementary way on vertical or horizontal geophones. The geometry of the VSP survey allows illuminating vertically and horizontally the GPK3 fault in the depth range 3 to 4.7 km and in a 1000m lateral interval respectively. In contrast, the 2D surface seismic lines shot around the wells show no reliable reflections within the basement. In addition to the major fault, the Soultz VSP data include several evidences of basement faults where reflected waves and converted waves coincide at the well. VSP is one of the few geophysical techniques able to image fault zones within a deep seated granite.

  14. Study of the postseismic deformation transient due to the Mw6 2004 Parkfield earthquake using a new 3-D semi-analytic model of stress-driven fault creep

    Microsoft Academic Search

    S. Barbot; Y. Fialko

    2007-01-01

    We developed a new semi-analytic model of time-dependent aseismic fault slip driven by coseismic stress changes. The model uses elastic Greens functions, expressed analytically in the Fourier domain, to solve for the displacement due to an arbitrary set of body forces in a 3-D computational grid representing a heterogeneous visco-elastic half-space. The numerical approach makes use of the convolution theorem

  15. Enabling 3D geomechanical restoration of strike- and oblique-slip faults using geological constraints, with applications to the deep-water Niger Delta

    NASA Astrophysics Data System (ADS)

    Durand-Riard, Pauline; Shaw, John H.; Plesch, Andreas; Lufadeju, Gbenga

    2013-03-01

    We present a new approach of using local constraints on fault slip to perform three-dimensional geomechanical restorations. Geomechanical restoration has been performed previously on extensional and contractional systems, yet attempts to restore strike- and oblique-slip fault systems have generally failed to recover viable fault-slip patterns. The use of local measures of slip as constraints in the restoration overcomes this difficulty and enables restorations of complex strike- and oblique slip-systems. To explore this approach, we develop a synthetic restraining bend system to evaluate different ways that local slip constraints can be applied. Our restorations show that classical boundary conditions fail to reproduce the fault offset and strain pattern. In contrast, adding piercing points and/or properly constraining lateral walls enables restoration of the structure and resolves the correct pattern of slip along the faults. We then restore a complex system of tear-faults in the deepwater Niger Delta basin. We use channel offsets imaged by the seismic data to define local fault-slip constraints. Balancing these constraints equally on both sides of the major faults yields the most consistent restoration outcomes. This approach resolves reasonable slip styles on the complex set of thrust, normal, and strike-slip faults in the structure. This suggests that limited geologic fault slip constraints can be effectively incorporated in geomechanical restorations, yielding accurate restoration kinematics and thereby forecasting faults slip patterns within the structures.

  16. A free software for pore-scale modelling: solving Stokes equation for velocity fields and permeability values in 3D pore geometries

    NASA Astrophysics Data System (ADS)

    Gerke, Kirill; Vasilyev, Roman; Khirevich, Siarhei; Karsanina, Marina; Collins, Daniel; Korost, Dmitry; Mallants, Dirk

    2015-04-01

    In this contribution we introduce a novel free software which solves the Stokes equation to obtain velocity fields for low Reynolds-number flows within externally generated 3D pore geometries. Provided with velocity fields, one can calculate permeability for known pressure gradient boundary conditions via Darcy's equation. Finite-difference schemes of 2nd and 4th order of accuracy are used together with an artificial compressibility method to iteratively converge to a steady-state solution of Stokes' equation. This numerical approach is much faster and less computationally demanding than the majority of open-source or commercial softwares employing other algorithms (finite elements/volumes, lattice Boltzmann, etc.) The software consists of two parts: 1) a pre and post-processing graphical interface, and 2) a solver. The latter is efficiently parallelized to use any number of available cores (the speedup on 16 threads was up to 10-12 depending on hardware). Due to parallelization and memory optimization our software can be used to obtain solutions for 300x300x300 voxels geometries on modern desktop PCs. The software was successfully verified by testing it against lattice Boltzmann simulations and analytical solutions. To illustrate the software's applicability for numerous problems in Earth Sciences, a number of case studies have been developed: 1) identifying the representative elementary volume for permeability determination within a sandstone sample, 2) derivation of permeability/hydraulic conductivity values for rock and soil samples and comparing those with experimentally obtained values, 3) revealing the influence of the amount of fine-textured material such as clay on filtration properties of sandy soil. This work was partially supported by RSF grant 14-17-00658 (pore-scale modelling) and RFBR grants 13-04-00409-a and 13-05-01176-a.

  17. MICADO: Parallel implementation of a 2D-1D iterative algorithm for the 3D neutron transport problem in prismatic geometries

    SciTech Connect

    Fevotte, F.; Lathuiliere, B. [EDF R and D (France)

    2013-07-01

    The large increase in computing power over the past few years now makes it possible to consider developing 3D full-core heterogeneous deterministic neutron transport solvers for reference calculations. Among all approaches presented in the literature, the method first introduced in [1] seems very promising. It consists in iterating over resolutions of 2D and ID MOC problems by taking advantage of prismatic geometries without introducing approximations of a low order operator such as diffusion. However, before developing a solver with all industrial options at EDF, several points needed to be clarified. In this work, we first prove the convergence of this iterative process, under some assumptions. We then present our high-performance, parallel implementation of this algorithm in the MICADO solver. Benchmarking the solver against the Takeda case shows that the 2D-1D coupling algorithm does not seem to affect the spatial convergence order of the MOC solver. As for performance issues, our study shows that even though the data distribution is suited to the 2D solver part, the efficiency of the ID part is sufficient to ensure a good parallel efficiency of the global algorithm. After this study, the main remaining difficulty implementation-wise is about the memory requirement of a vector used for initialization. An efficient acceleration operator will also need to be developed. (authors)

  18. Seismic fault geometry and kinematics of the 13 May 1995 Western Macedonia (Greece) earthquake

    Microsoft Academic Search

    D. Mountrakis; S. Pavlides; N. Zouros; Th. Astaras; A. Chatzipetros

    1998-01-01

    During the devastating earthquake of 13 May 1995, in the Kozani-Grevena area (Western Macedonia, Greece), many surface ruptures formed in the epicentral area. Most of these fractures were due to faulting, but some were secondary ground ruptures and landslides.Geological field work in the area has shown that the Aliakmon river neotectonic fault consists of several (three or more) fault strands:

  19. 3-D Discrete Analytical Ridgelet Transform

    Microsoft Academic Search

    David Helbert; Philippe Carre; Eric Andres

    2006-01-01

    In this paper, we propose an implementation of the 3-D ridgelet transform: The 3-D Discrete Analytical Ridgelet Transform (3-D DART). This transform uses the Fourier strategy for the computation of the associated 3-D discrete Radon transform. The innovative step is the definition of a discrete 3-D transform with the discrete analytical geometry theory by the construction of 3-D discrete analytical

  20. Radon concentrations in soil gas, considering radioactive equilibrium conditions with application to estimating fault-zone geometry

    NASA Astrophysics Data System (ADS)

    Koike, Katsuaki; Yoshinaga, Tohru; Asaue, Hisafumi

    2009-02-01

    A calculation method for determining the amount of Rn isotopes and daughter products at the start of measurement (CRAS) is proposed as a more accurate means of estimating the initial Rn concentration in soil gas. The CRAS utilizes the decay law between 222Rn and 220Rn isotopes and the daughter products 218Po and 216Po, and is applicable to ?-scintillation counter measurements. As Rn is both inert and chemically stable, it is useful for fault investigation based on the soil gas geochemistry. However, the total number of ? particles emitted by the decay of Rn has generally been considered to be proportional to the initial Rn concentration, without considering the gas condition with respect to radioactive equilibrium. The CRAS method is shown to be effective to derive Rn concentration for soil gases under both nonequilibrium conditions, in which the total number of decays increases with time, and equilibrium conditions, which are typical of normal soil under low gas flux. The CRAS method in conjunction with finite difference method simulation is applied to the analysis of two active fault areas in Japan, and it is demonstrated that this combination could detect the sharp rises in 222Rn concentrations associated with faults. The method also allows the determination of fault geometry near the surface based on the asymmetry variation of the Rn concentration distribution when coupled with a numerical simulation of 222Rn transport. The results for the new method as applied to the two case studies are consistent with the data collected from the geological survey. It implies that the CRAS method is suitable for investigating the fault system and interstitial gas mobility through fractures. The present analyses have also demonstrated that high Rn concentrations require the recent and repeated accumulation of 222Rn parents (230Th and 226Ra) in fault gouges through deep gas release during fault movement.

  1. Seismogenic Fault Geometry of 2010 Mw 7.1 Solomon Islands Earthquake

    NASA Astrophysics Data System (ADS)

    Kuo, Y.; Ku, C.; Taylor, F. W.; Huang, B.; Chen, Y.; Chao, W.; Huang, H.; Kuo, Y.; Wu, Y.; Suppe, J.

    2010-12-01

    The Solomon Islands is located in southwestern Pacific, where the Indo-Australian Plate is subducting northeastward beneath the Pacific Plate. Due to subduction of rugged seafloor topography, including seamounts, the seismic activity and tectonic behavior may be complicated. Seismicity in this region was anomalously low until 2007 when a megathrust rupture (Mw 8.1) occurred. More recently, on 3 January 2010, a Mw7.1 earthquake occurred beneath the extreme outer forearc next to the trench. It came with one foreshock (Mw 6.6, 50 minutes ahead) and two large aftershocks (Mw 6.8 and 6.0) greater than magnitude 6 within a week. It is interesting to note that these four focal mechanisms are very much similar and appear to have occurred along the interplate thrust zone between the Indo-Australian plate and Solomon Islands forearc. This Earthquake nucleated approximately 50 km to the southeast of the M8.1 Earthquake occurring in April of 2007, which is located to the other side of Rendova Island. Because a tsunami followed the 2010 earthquake, it is likely that submarine surface deformation accompanied the event. By the results of D-InSAR on ALOS and ERS, plus limited points of ground displacement from GPS and strong motion seismometers, the continuous ground displacement field is constructed and normalized. Our preliminary result shows the ground movement in the Rendova Island can reach tens of centimeters, implying shallow earthquake source consistent with the suggestion by triggering tsunami. Besides, the earthquake sequence retrieved from our local seismometer observation network allows us to further define underground fault geometry. The spatial distribution of the epicenter also concludes the seamount located in the middle divides two seismogenic asperities which generate 2007 and 2010 earthquakes respectively.

  2. Characterizing Geometry, Kinematics, and Fracturing of a Wavy Fault Surface, Arkitsa, Greece

    NASA Astrophysics Data System (ADS)

    Resor, P. G.; Meer, V. E.

    2006-12-01

    The Arkitsa fault is a high angle normal fault within the Gulf of Evvia rift system of central Greece. Quarrying of hanging wall sediments has exposed a 600 m length of a wavy footwall fault surface within Triassic/Jurassic platform carbonates. This excellent exposure enables examination of fault damage zone processes up to hundred meter scale. Using a robotic reflectorless total station we create a virtual fault surface with 1-m spatial resolution and sub-cm precision that extends over a length of 250 m and a vertical height of 60 m. Zones of extreme curvature (antiforms and synforms) parallel the average slip direction with approximately 7-m peak-to-peak spacing and thereby define the wavy fault surface. Detailed field measurements across the base of the scanned surface further characterize the fault orientation, slip, and footwall fractures. Fault strike varies over 75° with a mean of 291° while dip varies over 29° with a mean of 63°(n=165). The trend of slip indicators (surface grooves and slickenlines) varies over 57° with a mean of 342° while the plunge varies over 22° with a mean of 56° (n=162). Fracture density and orientation, measured at 24 circular scanlines, varies across the studied exposure and has little correlation to fault dip direction (P > 0.30). Open through-going fractures are oriented at a high angle to the observed slip direction with a mean strike of 59° and dip of 42° (n=317). The virtual fault surface and field measurements are integrated using sub- cm resolution digital orthophotos within a geographic information system (GIS). The integrated data allows for exploration of possible interactions among fault shape, fault slip, and footwall fractures.

  3. The 3-D Tectonic Crustal Stress Field and Style of Faulting Along the Pacific North America Plate Boundary in Southern California

    NASA Astrophysics Data System (ADS)

    Yang, W.; Hauksson, E.

    2012-12-01

    We invert for the state of stress in the southern California crust using recent high quality earthquake focal mechanisms catalog (1981-2010). To interpret the stress field we determine the maximum horizontal compressive stress (SHmax) orientations and the style of faulting across southern California at four different scales of resolution, with grid spacing of 5 and 10 km, and with 15 or 30 events per grid. The stress field is best resolved where seismicity rates are high but sufficient data are available to constrain the stress field across most of the region. The trend of SHmax exhibits significant regional and local spatial heterogeneities. The regional trend of SHmax varies from north along the San Andreas system to NNE to the east in the Eastern California Shear Zone as well as to the west, within the Continental Borderland and the western Transverse Ranges. The transition zones from one state of stress to the other are very sharp and occur over a distance of a few kilometers, following a trend from Yucca Valley to Imperial Valley to the east, and the western edge of the Peninsular Ranges to the west. The local scale heterogeneities in the SHmax trend include NNW trends along the San Andreas Fault near Cajon Pass, Tejon Pass, and the Cucapa Range, as well as NNE trends near the northern San Jacinto Fault and the Wheeler Ridge region. The style of faulting exhibits similar complexity, ranging from predominantly normal faulting in the high Sierra Nevada, to strike-slip faulting along the San Andreas system, to three consecutive bands of thrust faulting in the Wheeler Ridge area and the western Transfer Ranges. The local variations in the style of faulting include normal faulting at the north end of the San Jacinto Fault and scattered regions of thrust faulting. We compare the pattern of SHmax trend in the crust with the GPS measured maximum shortening strain rate tensor and upper mantle anisotropy. The regional variations in the SHmax trends are very similar to the pattern of the maximum shortening axes of surface strain rate tensor field although the strain filed tends to be smoother and appears to capture some of the upper mantle deformation field. The mean trend of SHmax depart about approximately 14° to the east from the trend of the maximum shortening directions of anisotropy in the upper mantle.tacked SHmax profile across the Cajon Pass from the Continental Borderland to the Basin and Range. GPS velocity profile is in cyan.

  4. Shallow Geometry and Velocities Along the Rialto-Colton Fault, San Bernardino Basin, California

    NASA Astrophysics Data System (ADS)

    Gandhok, G.; Catching, R. D.; Rymer, M. J.; Goldman, M. R.

    2003-12-01

    The Rialto-Colton fault, part of and located southwest of the San Jacinto fault zone, extends along the southwestern margin of the San Bernardino basin. There, the Rialto-Colton fault is buried beneath Quaternary alluvium. Ground-water studies suggest that the Rialto-Colton fault extends northwestward, structurally bounding the San Bernardino basin and acting as a ground-water barrier. Potential-field studies also show evidence for variations in basement depth along the presumed trace of the fault. To better locate the Rialto-Colton fault and to better assess its potential earthquake hazard, the U.S. Geological Survey acquired five combined, high-resolution seismic reflection and refraction profiles along the expected trace of the fault. Our seismic reflection images show that the Rialto-Colton fault consists of an approximately 1-km-wide zone of small-offset (approximately 20 to 30 m) faults in the upper 1 km depth. No single large-offset fault was imaged along any of the seismic profiles. Reflections extend to depths of at least 800 m along most of the seismic profiles, suggesting that basement is at least 800 m deep. We also used tomographic methods to invert first-arrival refractions for the velocity structure along each of the seismic profiles. P-wave velocities range from about 300 m/s at the surface to about 2500 m/s at depths of about 100 m. Our seismic velocity images show that the ground-water table largely correlates with the 1500 m/s contours, and the velocity images show that the ground-water table is disrupted across the reflection-imaged fault zone at shallow depths. Some of the faults extend to within a few meters of the surface, suggesting that there has been recent activity on the Rialto-Colton fault. Because the densely populated and growing cites of San Bernardino, Rialto, Colton, and Fontana are located along the projected trend of the Rialto-Colton fault, rupture along the fault may present a significant earthquake hazard to the region.

  5. Simple 3D Drawing

    NSDL National Science Digital Library

    Ensley, Doug

    Developed by Barbara Kaskosz of the University of Rhode Island and Doug Ensley of Shippensburg University, this resource from The Mathematical Association of America's Digital Classroom Resources collection will prove quite valuable for educators and anyone with an interest in computer graphics or geometry. Through this resource, visitors will learn how to draw and rotate 3D objects via a series of short tutorials. Along the way, users will learn about the mathematics behind manipulating cubes, the geometry involved with the manipulation of cubes, and they will also get a chance to work on their own structures. Overall, it's a fine resource and it offers insights for students in several different disciplines.

  6. Simple 3D Drawing

    NSDL National Science Digital Library

    Developed by Barbara Kaskosz of the University of Rhode Island and Doug Ensley of Shippensburg University, this resource from The Mathematical Association of America's Digital Classroom Resources collection will prove quite valuable for educators and anyone with an interest in computer graphics or geometry. Through this resource, visitors will learn how to draw and rotate 3D objects via a series of short tutorials. Along the way, users will learn about the mathematics behind manipulating cubes, the geometry involved with the manipulation of cubes, and they will also get a chance to work on their own structures. Overall, it's a fine resource and it offers insights for students in several different disciplines

  7. Re-evaluation of Fault Geometry and Slip Distribution of the 1944 Bolu-Gerede Earthquake Rupture, North Anatolian Fault System, Turkey

    NASA Astrophysics Data System (ADS)

    Kondo, H.; Awata, Y.; Emre, O.; Dogan, A.; Ozalp, S.; Tokay, F.; Yildirim, C.

    2002-12-01

    The successive earthquakes along the North Anatolian Fault System in 20th century provides us fundamental data on fault segmentation, characteristics faulting behavior, and dimensions and scaling laws of faulting. In this point of view, we re-evaluate geometry and slip-distribution of the Ms7.3 Bolu-Gerede earthquake rupture of 1944, which has not been studied since 1970. The 1944 rupture is traceable for about 185-km, from 30-km west of Bolu (40.6N, 31.4E) to 20-km west of Ilgaz (41.0N, 33.4E) almost continuously and straightly, trending N75E. Amount of slip along the rupture varies between 2 and 6 m right-laterally. In the middle-east section of the rupture, east of Gerede, the slip is as large as 4.5 to 6 m. Along the other sections, the amount of slip decreases to about 2-4 m. The rupture can be subdivided into 5 to 7 geometrical segments of 10 to 45-km-long, which are separated by small separation, bend, step, push-up and pull-apart structures. At 6-km east of Iametpasa (40.9N, 32.7E), a series of foundation of a stone-bridge, which is built approximately AD 680+190-90 (Ikeda, 1994), has been offset for about 20 m. The 3.5 to 4.0 m slip-per-event during the 1944 earthquakes suggests that the 20 m displacement has been accumulated by 5 to 6 faulting events with an average recurrence interval of about 200 to 350 years. Re-evaluated average slip of the 1944 rupture is about 3.5 m that is almost twice of the previously well-known amount. The straightness and continuance of the fault strands foresee that the 1944 earthquake had more simple rupture process and shorter source time than those of 1999 Izmit earthquake of Ms 7.4.

  8. Relay zone geometry and displacement transfer between normal faults recorded in coal-mine plans

    Microsoft Academic Search

    P. Huggins; J. Watterson; J. J. Walsh; C. Childs

    1995-01-01

    Overlap lengths, separations and throw gradients were measured on 132 relay zones recorded on coal-mine plans. Throws on the relay-bounding fault traces are usually ? 2 m and individual structures are recorded on only one seam. Throw gradients associated with relay zones are not always higher than on single faults, but asymmetry of throw profiles is diagnostic of relay zones.

  9. Extrapolating subsurface geometry by surface expressions in transpressional strike slip fault, deduced from analogue experiments with settings of rheology and convergence angle

    NASA Astrophysics Data System (ADS)

    Hsieh, Shang Yu; Neubauer, Franz

    2015-04-01

    The internal structure of major strike-slip faults is still poorly understood, particularly how to extrapolate subsurface structures by surface expressions. Series of brittle analogue experiments by Leever et al., 2011 resulted the convergence angle is the most influential factor for surface structures. Further analogue models with different ductile settings allow a better understanding in extrapolating surface structures to the subsurface geometry of strike-slip faults. Fifteen analogue experiments were constructed to represent strike-slip faults in nature in different geological settings. As key parameters investigated in this study include: (a) the angle of convergence, (b) the thickness of brittle layer, (c) the influence of a rheological weak layer within the crust, and (d) influence of a thick and rheologically weak layer at the base of the crust. The experiments are aimed to explain first order structures along major transcurrent strike-slip faults such as the Altyn, Kunlun, San Andrea and Greendale (Darfield earthquake 2010) faults. The preliminary results show that convergence angle significantly influences the overall geometry of the transpressional system with greater convergence angles resulting in wider fault zones and higher elevation. Different positions, densities and viscosities of weak rheological layers have not only different surface expressions but also affect the fault geometry in the subsurface. For instance, rheological weak material in the bottom layer results in stretching when experiment reaches a certain displacement and a buildup of a less segmented, wide positive flower structure. At the surface, a wide fault valley in the middle of the fault zone is the reflection of stretching along the velocity discontinuity at depth. In models with a thin and rheologically weaker layer in the middle of the brittle layer, deformation is distributed over more faults and the geometry of the fault zone below and above the weak zone shows significant differences, suggesting that the correlation of structures across a weak layer has to be supported by geophysical data, which help constraining the geometry of the deep part. This latter experiment has significantly similar phenomena in reality, such as few pressure ridges along Altyn fault. The experimental results underline the need to understand the role of the convergence angle and the influence of rheology on fault evolution, in order to connect between surface deformation and subsurface geometry.

  10. Fault architecture, fault rocks and fault rock properties in carbonate rocks

    NASA Astrophysics Data System (ADS)

    Bauer, Helene; Decker, Kurt

    2010-05-01

    Fault architecture, fault rocks and fault rock properties in carbonate rocks The current study addresses a comparative analysis of fault zones in limestone and dolomite rocks comparing the architecture of fault core and damage zones, fault rocks, and the hydrodynamic properties of faults exposed in the Upper Triassic Wetterstein Fm. of the Hochschwab Massif (Austria). All analysed faults are sinistral strike-slip faults, which formed at shallow crustal depth during the process of eastward lateral extrusion of the Eastern Alps in the Oligocene and Lower Miocene Fault zones in limestone tend to be relatively narrow zones with distinct fault core and damage zones. Fault cores, which include the principle slip surface of the fault, are characterized by cataclastic fault rock associated with slickensides separating strands of catalasite from surrounding host rock or occurring between different types of cataclasite. Cataclasites differ in terms of fragment size, matrix content and the angularity of fragments,. Cataclasite fabrics indicate progressive cataclasis and substantial displacement across the fault rock. Fault core heterogeneity tends to decrease within more evolved (higher displacement) faults. In all fault cores cataclasites are localized within strands, which connect to geometrically complex anastomosing volumes of fault rock. The 3D geometry of such fault cores is difficult to resolve on the outcrop scale. Beside cataclastic flow pressure solution, overprinting cataclastic fabrics, could be documented within fault zones. Damage zones in limestone fault zones are characterized by intensively fractured (jointed) host rock and dilatation breccias, indicating dilatation processes and peripheral wall rock weakening accompanying the growth of the fault zone. Dilatation breccias with high volumes of carbonate cement indicate these processes are related to high fluid pressure and the percolation of large volumes of fluid. Different parts of the damage zones were differentiated on the base of variable fracture densities. Fracture densities (P32 in m² joint surfaces per m³ rock) generally vary along all investigated faults. They are especially high in more evolved (higher displacement) fault zones where they are associated with large-scale Riedel sehars and in parts of the damage zones, that are next to the fault cores. The assessment of the abundance of small-scale fractures uses fracture facies as an empirical classification providing semi-quantitative estimates of fracture density and abundance. Different units were assigned to fracture facies 1 to 4, with fracture facies 4 indicating highest fracture density. Fault zones in dolomite tend to have several fault cores localized within wider zones of fractured wall rock (damage zones), even at low strain. Compared to fault zones with similar displacement in limestone, damage zones in dolomite tend to be wider and have higher fracture densities. Dilatation breccias are more abundant. A clear separation of fault core and damage zone is more difficult. Damage zones observed at the lateral (mode III) tips of the analysed strike-slip faults show that hydraulic fracturing and fluid flow through the propagating fault are of major importance for its evolution. A typical transition from the wall rock ahead of the propagating fault to the core of the slipped fault includes: densely jointed wall rock, wall rock with abundant cement-filled tension gashes, dilatation breccia and cataclasite reworking both dilatation breccia and wall rock. The detailed documentation of different fault zone units is supplemented by porosity measurements in order to assess the hydrogeological properties of the fault zones. High permeability units are first of all located in the damage zones, characterized by high fracture densities. Porosity measurements on fault rocks showed highest porosity (up to 6%) for fractured wall rocks (fracture facies 4) and dilatation breccias (porosity of undeformed wall rock: 1,5 % average, 2 % maximum). Thin sections prove that most of the porosity is carried by uncemented f

  11. Controlled Fabrication of Microparticles with Complex 3D Geometries by Tunable Interfacial Deformation of Confined Polymeric Fluids in 2D Micromolds.

    PubMed

    Choi, Chang-Hyung; Lee, Byungjin; Kim, Jongmin; Nam, Jin-Oh; Yi, Hyunmin; Lee, Chang-Soo

    2015-06-01

    Polymeric microparticles with complex shapes have attracted substantial attention in many application areas because particle shape is a critical parameter to impart programmable functionalities. The formation of specific three-dimensional (3D) microstructures in a simple, scalable, and controllable manner is difficult. Here, we report the controlled fabrication of microparticles with complex 3D shapes based on the simple tuning of mold swelling and capillarity. Specifically, a photocurable solution loaded in micromolds is spatially deformed into complex shapes depending on the degree of molding swelling and capillarity, thereby producing polymeric microparticles with controlled 3D shapes upon photopolymerization. The results show that highly uniform microparticles with controlled two-dimensional (2D) and 3D shapes were fabricated from identical 2D micromolds via the simple tuning of the wetting fluids. This technique can be extended to produce highly complex microarchitectures with controlled 3D geometric domains via 2D mold designs. Finally, multicompartment microparticles with independently controlled 3D shapes for each compartment are produced by a simple combination of fabrication sequences. We envision that this strategy of producing 3D microarchitectures from easily designed simple micromolds could provide a path to new materials and new properties. PMID:25920947

  12. Geometry

    NSDL National Science Digital Library

    Rusin, Dave

    A short article designed to provide an introduction to geometry, including classical Euclidean geometry and synthetic (non-Euclidean) geometries; analytic geometry; incidence geometries (including projective planes); metric properties (lengths and angles); and combinatorial geometries such as those arising in finite group theory. Many results in this area are basic in either the sense of simple, or useful, or both. History; applications and related fields and subfields; textbooks, reference works, and tutorials; software and tables; other web sites with this focus.

  13. Transfer zones in listric normal fault systems

    NASA Astrophysics Data System (ADS)

    Bose, Shamik

    Listric normal faults are common in passive margin settings where sedimentary units are detached above weaker lithological units, such as evaporites or are driven by basal structural and stratigraphic discontinuities. The geometries and styles of faulting vary with the types of detachment and form landward and basinward dipping fault systems. Complex transfer zones therefore develop along the terminations of adjacent faults where deformation is accommodated by secondary faults, often below seismic resolution. The rollover geometry and secondary faults within the hanging wall of the major faults also vary with the styles of faulting and contribute to the complexity of the transfer zones. This study tries to understand the controlling factors for the formation of the different styles of listric normal faults and the different transfer zones formed within them, by using analog clay experimental models. Detailed analyses with respect to fault orientation, density and connectivity have been performed on the experiments in order to gather insights on the structural controls and the resulting geometries. A new high resolution 3D laser scanning technology has been introduced to scan the surfaces of the clay experiments for accurate measurements and 3D visualizations. Numerous examples from the Gulf of Mexico have been included to demonstrate and geometrically compare the observations in experiments and real structures. A salt cored convergent transfer zone from the South Timbalier Block 54, offshore Louisiana has been analyzed in detail to understand the evolutionary history of the region, which helps in deciphering the kinematic growth of similar structures in the Gulf of Mexico. The dissertation is divided into three chapters, written in a journal article format, that deal with three different aspects in understanding the listric normal fault systems and the transfer zones so formed. The first chapter involves clay experimental models to understand the fault patterns in divergent and convergent transfer zones. Flat base plate setups have been used to build different configurations that would lead to approaching, normal offset and overlapping faults geometries. The results have been analyzed with respect to fault orientation, density, connectivity and 3D geometry from photographs taken from the three free surfaces and laser scans of the top surface of the clay cake respectively. The second chapter looks into the 3D structural analysis of the South Timbalier Block 54, offshore Louisiana in the Gulf of Mexico with the help of a 3D seismic dataset and associated well tops and velocity data donated by ExxonMobil Corporation. This study involves seismic interpretation techniques, velocity modeling, cross section restoration of a series of seismic lines and 3D subsurface modeling using depth converted seismic horizons, well tops and balanced cross sections. The third chapter deals with the clay experiments of listric normal fault systems and tries to understand the controls on geometries of fault systems with and without a ductile substrate. Sloping flat base plate setups have been used and silicone fluid underlain below the clay cake has been considered as an analog for salt. The experimental configurations have been varied with respect to three factors viz. the direction of slope with respect to extension, the termination of silicone polymer with respect to the basal discontinuities and overlap of the base plates. The analyses for the experiments have again been performed from photographs and 3D laser scans of the clay surface.

  14. Geometry, kinematics and slip rate along the Mosha active fault, Central Alborz, Iran

    NASA Astrophysics Data System (ADS)

    Ritz, J.-F.; Pics Geological Team

    2003-04-01

    The Mosha fault is one of the major active fault in Central Alborz as shown by its strong historical seismicity and its clear morphological signature. Situated at the vicinity of Tehran city, this ~150 km long ~N100°E trending fault represents an important potential seismic source that threatens the Iranian metropolis. In the framework of an Iranian-French joint research program (PICS) devoted to seismic hazard assessment in the Tehran region, we undertook a morphotectonic (determination of the cumulative displacements and the ages of offset morphologic markers) and paleoseismic (determination of the ages and magnitudes of ancient events) study along the Mosha fault. Our objectives are the estimation of the long-term slip rate (Upper Pleistocene-Holocene) and the mean recurrence interval of earthquakes along the different segments of the fault. Our investigations within the Tar Lake valley, along the eastern part of the fault potentially the site of the 1665 (VII, 6.5) historical earthquake - allows us to calculate a preliminary 2 ± 0.1 mm/yr minimum left lateral slip rate. If we assume a characteristic coseismic average displacement comprised between 0.35 m (Mw 6.5) and 1.2 m (Mw 7.1) calculated from Wells &Coppersmith’s functions (1994) and taking the moment magnitudes attributed to the 1665 and 1830 earthquakes (e.g. Berberian &Yeats, 2001) the mean maximum recurrence intervals along this segment of the Mosha fault are comprised between 160 and 620 yrs.

  15. Self-calibration of cone-beam CT geometry using 3D-2D image registration: development and application to tasked-based imaging with a robotic C-arm

    NASA Astrophysics Data System (ADS)

    Ouadah, S.; Stayman, J. W.; Gang, G.; Uneri, A.; Ehtiati, T.; Siewerdsen, J. H.

    2015-03-01

    Purpose: Robotic C-arm systems are capable of general noncircular orbits whose trajectories can be driven by the particular imaging task. However obtaining accurate calibrations for reconstruction in such geometries can be a challenging problem. This work proposes a method to perform a unique geometric calibration of an arbitrary C-arm orbit by registering 2D projections to a previously acquired 3D image to determine the transformation parameters representing the system geometry. Methods: Experiments involved a cone-beam CT (CBCT) bench system, a robotic C-arm, and three phantoms. A robust 3D-2D registration process was used to compute the 9 degree of freedom (DOF) transformation between each projection and an existing 3D image by maximizing normalized gradient information with a digitally reconstructed radiograph (DRR) of the 3D volume. The quality of the resulting "self-calibration" was evaluated in terms of the agreement with an established calibration method using a BB phantom as well as image quality in the resulting CBCT reconstruction. Results: The self-calibration yielded CBCT images without significant difference in spatial resolution from the standard ("true") calibration methods (p-value >0.05 for all three phantoms), and the differences between CBCT images reconstructed using the "self" and "true" calibration methods were on the order of 10-3 mm-1. Maximum error in magnification was 3.2%, and back-projection ray placement was within 0.5 mm. Conclusion: The proposed geometric "self" calibration provides a means for 3D imaging on general noncircular orbits in CBCT systems for which a geometric calibration is either not available or not reproducible. The method forms the basis of advanced "task-based" 3D imaging methods now in development for robotic C-arms.

  16. Threshold Voltage model for mesa-isolated small geometry fully depleted SOI MOSFETs based on analytical solution of 3-D Poisson's equation

    Microsoft Academic Search

    Guruprasad Katti; Nandita DasGupta; Amitava DasGupta

    2004-01-01

    A threshold voltage model for mesa-isolated fully depleted silicon-on-insulator (FDSOI) MOSFETs, based on the analytical solution of three-dimensional (3-D) Poisson's equation is presented for the first time in this paper. The separation of variables technique is used to solve the 3-D Poisson's equation analytically with appropriate boundary conditions. Simple and accurate analytical expressions for the threshold voltage of the front

  17. A 3-D Semi-analytic Viscoelastic Model of the San Andreas Fault System: A 1000-year Perspective of the Earthquake Cycle

    Microsoft Academic Search

    B. R. Smith; D. T. Sandwell

    2004-01-01

    Combining historical earthquake data, coastal tide gauge measurements, and continuous vertical and horizontal geodetic velocities, we simulate one thousand years of the earthquake cycle for the entire San Andreas Fault System. We employ a model based on a new semi-analytic solution that provides the displacement and stress caused by time-dependent dislocations embedded in an elastic layer overlying a Maxwell viscoelastic

  18. Facies composition and scaling relationships of extensional faults in carbonates

    NASA Astrophysics Data System (ADS)

    Bastesen, Eivind; Braathen, Alvar

    2010-05-01

    Fault seal evaluations in carbonates are challenged by limited input data. Our analysis of 100 extensional faults in shallow-buried layered carbonate rocks aims to improve forecasting of fault core characteristics in these rocks. We have analyzed the spatial distribution of fault core elements described using a Fault Facies classification scheme; a method specifically developed for 3D fault description and quantification, with application in reservoir modelling. In modelling, the fault envelope is populated with fault facies originating from the host rock, the properties of which (e.g. dimensions, geometry, internal structure, petrophysical properties, and spatial distribution of structural elements) are defined by outcrop data. Empirical data sets were collected from outcrops of extensional faults in fine grained, micro-porosity carbonates from western Sinai (Egypt), Central Spitsbergen (Arctic Norway), and Central Oman (Adam Foothills) which all have experienced maximum burial of 2-3 kilometres and exhibit displacements ranging from 4 centimetres to 400 meters. Key observations include fault core thickness, intrinsic composition and geometry. The studied fault cores display several distinct fault facies and facies associations. Based on geometry, fault cores can be categorised as distributed or localized. Each can be further sub-divided according to the presence of shale smear, carbonate fault rocks and cement/secondary calcite layers. Fault core thickness in carbonate rocks may be controlled by several mechanisms: (1) Mechanical breakdown: Irregularities such as breached relays and asperities are broken down by progressive faulting and fracturing to eventually form a thicker fault rock layer. (2) Layer shearing: Accumulations of shale smear along the fault core. (3) Diagenesis; pressure solution, karstification and precipitation of secondary calcite in the core. Observed fault core thicknesses scatter over three orders of magnitude, with a D/T range of 1:1 to 1:1000. In general the complete dataset shows a positive correlation between thickness (T) of fault cores and the displacement (D) on faults. For increasing displacement relationships, the D/T relationship is not constant. The D/T relationship is generally higher for small faults than for larger faults, which implies that comparisons between small and large fault with respect to this parameter should be handled with care. Fault envelope composition, as reflected by the relative proportions of different fault facies in the core, varies with displacement. In small scale faults (0-1 m displacement), secondary calcite layers and fault gouge dominate, whereas shale dominated fault rocks (shale smear) and carbonate dominated fault rocks (breccias) constitute minor components. Shale dominated fault rocks are restricted to shale-rich protoliths, and fault breccias to break-down of lenses formed near fault jogs. In medium scale faults (1-10m), fault rocks form the dominating facies, whereas the amount of secondary calcite layers decreases due to transformation into breccias. Further, in shale rich carbonates the fault cores consist of composite facies associations. In major faults (10-300 m displacement) fault rock layers and lenses dominate the fault cores. A common observation in large scale faults is a distinct layering of different fault rocks, shale smearing of major shale layers and massive secondary calcite layers along slip surfaces. Fault core heterogeneity in carbonates is ascribed to the distribution of fault facies, such as fault rocks, secondary calcite layers and shale smear. In a broader sense, facies distribution and thickness are controlled by displacement, protolith and tectonic environment. The heterogeneous properties and the varied distribution observed in this study may be valuable in forecasting fault seal characteristics of carbonate reservoirs.

  19. Large-scale geometry and evolution of the Karakorum Fault, W-Tibet.

    NASA Astrophysics Data System (ADS)

    Lacassin, R.; Valli, F.; Arnaud, N.; Leloup, P. H.; Li, H.; Tapponnier, P.; Paquette, J. L.; Chevalier, M. L.; Guillot, S.; Xu, Z.

    2003-04-01

    Discriminating between localized and distributed deformation in the continental lithosphere requires to determine the kinematics of large-scale fault zones. In the India-Asia collision zone, the total offset, activity span and slip rate of the Karakorum fault zone (KFZ) are amongst the most debated. We discuss new structural and age data from the southern fault-half, which must be taken into account. SE of Lat 33N (W of Shiquanhe), the active KFZ splays into several strike-slip branches that offset quaternary fans and moraines along the Tashikang-Gar basin. Southwards, some of these branches become oblique normal faults that exhume metamorphic and magmatic rocks of the Karakorum range. Along the NE border of the range, mylonites and gneisses with clear evidence of ductile dextral shear are intruded by synkinematic leucogranites. Conventional U/Pb on zircons from these leucogranites show a spread of age between 20 and 24 Ma, identical to direct ion probe dating of zircons. The uncertainties are largely due to inheritance. Cooling was delayed until ca.10Ma, at which time very rapid cooling is recorded by 40Ar/39Ar and fission track data, in various lithologies and locations along the fault, up to 800 km apart (Karakorum range at Lat 32.5N, Tashkorgan region, Lat 37.7N). Purely strike-slip ductile shear was thus already in progress along the fault at ca.22Ma. A change to oblique dextral-normal motion may have occurred around 10Ma. Cartographic evidence for strike-slip faulting is also clear within the Karakorum range and along its SW border where it resulted in large-scale boudinage of ophiolite units. North of the range, the ophiolite bearing melange of Shiquanhe possibly corresponds to the Shyok suture zone, offset right-lateraly by at least 300km. South of Baer, in the Menshi-Kailas region, we found no clear outcrop of ductilely sheared rocks but the evidence for recent strike-slip faulting is abundant. Several active strike-slip branches bound the Kailas range to the south and continue eastwards at least up to Long 82.5E. The south Kailas counterthrust system and melange zone of A.Gansser is in fact a transpressive flower structure, with clear microtectonic evidence for brittle dextral shear. Since it is part of the shear zone, this counterthrust cannot be used to estimate the total offset the KFZ, as has been proposed. There is no evidence that the KFZ connects directly with the Gurla Mandatha detachment zone. Instead, south of Kailas, the Karakorum fault appears to continue eastwards along the Indus-Tsangpo suture zone.

  20. Large-scale geometry, offset and kinematic evolution of the Karakorum fault, Tibet

    NASA Astrophysics Data System (ADS)

    Lacassin, Robin; Valli, Franck; Arnaud, Nicolas; Leloup, P. Hervé; Paquette, Jean Louis; Haibing, Li; Tapponnier, Paul; Chevalier, Marie-Luce; Guillot, Stephane; Maheo, Gweltaz; Zhiqin, Xu

    2004-03-01

    The total offset, lifespan and slip rate of the Karakorum fault zone (KFZ) (western Tibet) are debated. Along the southern fault half, ongoing oblique slip has exhumed dextrally sheared gneisses intruded by synkinematic leucogranites, whose age (˜23 Ma, U/Pb on zircon) indicates that right-lateral motion was already in progress in the late Oligocene. Ar/Ar K-feldspar thermochronology confirms that rapid cooling started around 12 Ma, likely at the onset of the present dextral normal slip regime. Correlation of suture zones across the fault requires a total offset greater than 250 km along the active - northern - fault branch. An average long-term slip rate of 1±0.3 cm/yr is inferred assuming that this offset accrued in a time span of 23-34 Ma. Southwest of the Ladakh-Karakorum Range, the large-scale boudinage of ophiolitic units suggests that an offset of several hundreds of kilometers exists along another - southern - branch of the KFZ. Towards the southeast, in the Mount Kailas region, the fault zone does not end at Gurla Mandatha, but continues eastwards, as a transpressive flower structure, along the Indus-Tsangpo suture. Our new data thus suggest that the KFZ contributed to absorb hundreds of kilometers of India-Asia convergence.

  1. Fab trees for designing complex 3D printable materials

    E-print Network

    Wang, Ye, M. Eng. Massachusetts Institute of Technology

    2013-01-01

    With more 3D printable materials being invented, 3D printers nowadays could replicate not only geometries, but also appearance and physical properties. On the software side, the tight coupling between geometry and material ...

  2. The Makerbot: Desktop 3D printing

    E-print Network

    Roughan, Matthew

    The Makerbot: Desktop 3D printing Matthew Roughan School of Mathematical Sciences matthew is Lots of maths hidden in something like 3D printing Geometry and Linear algebra ++ Same math used #12;CNC CNC = Computer Numerical Control CNC machines have been around for a while 3D printers

  3. On the Effects of Non-planar Geometry for Blind Thrust Faults on Strong Ground Motion

    E-print Network

    Olsen, Kim Bak

    of synthetic seismograms for several simple rupture scenarios with planar and curved fault approximations propagation and computation of synthetic seismograms are modeled using a fourth-order finite- difference-element method with an unstructured mesh. Here we use the boundary integral equation method (BIEM), which

  4. Quantitative Process of CAOB Orogeny: Insights into the Geometry and Kinematic Evolution of the Central Segment of Wu'erhe-Xiazijie Fault at the Northwestern Margin of Junggar Basin, China

    NASA Astrophysics Data System (ADS)

    He, Dengfa; Wu, Xiaozhi; ma, Delong

    2014-05-01

    How do the Central Asia Orogenic Belts (CAOB) accrete or propagate since the Carboniferous Period is a key issue to understand its orogenic style and evolution processes. To make use of the new acquired seismic data, 2-D and 3-D, drilled cores and logging data, and surface geology at the Wu'erhe-Xiazijie thrust zone (WXTZ) at the northwestern margin of Junggar Basin, the paper studies the geometry and kinematics of the central segment of WXTZ. At the end of Carboniferous, it formed a fault-bend fold in the Carboniferous with the thrust fault (F1) soled into the intra-Carboniferous detachment zone and stepped-up to the surface and subjected to erosion, and thus with the very lowest Permian Jiamuhe Formation (P1j) unconformablly overlain it. The slip and horizontal shortening of F1 are 2.69km and 2.66km respectively. The second phase of thrusting was in the depositional stage of Early Permian Fengcheng Formation (P1f). By utilizing the old lower flat (F1) and a new upper detachment (F2) in the top Carboniferous it formed a tectonic wedge with a back-thrust fault developed in the overlying strata. The slip and horizontal shortening of the wedge are 9.93km and 9.43km respectively. Then it subsided and filled with thick-sediments till the earliest Triassic Period. The third phase of thrusting formed a meso-scale fault-bend fold in the Permian with the F2 as the lower detachment and the upper flat (F3) located at the base of Fengcheng Formation (P1f). The slip and horizontal shortening of the fault (F2 or F3) are the same as 4.48km. The fourth phase of thrusting took place at the latest Triassic, the fault (F4) cutoff F2 downwards and propagated upward into the upper Permian and formed a fault-propagation fold in the Triassic strata, with the fault-slip and horizontal shortening of 4.67km and 4.07km respectively. The fault-propagation fold is so-called Fengcheng anticline and a giant oil field nowadays. Besides thrusting of F4, the thrust faults, Wulanlinge( F5) and Da'erbut (F6) thrust also into the basin in a backward sequence at this time of period. Since Jurassic, it evolved into a quiescent period with the Jurassic, Cretaceous, and Paleogene strata upwardly onlapping the thrust zone. However, the Da'erbut Fault (F6) reactivated during the Late Neogene to the Quaternary. It showed a composite character of sinistral strike-slipping and reverse-faulting, which modified the structure of WXTZ. WXTZ shows episodic thrusting during Carboniferous to Triassic and exhibits a breaking-backward style with the fault-slip and horizontal shortening more than 21.74km and 20.64km respectively.

  5. 3D field harmonics

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.

    1991-03-30

    We have developed an harmonic representation for the three dimensional field components within the windings of accelerator magnets. The form by which the field is presented is suitable for interfacing with other codes that make use of the 3D field components (particle tracking and stability). The field components can be calculated with high precision and reduced cup time at any location (r,{theta},z) inside the magnet bore. The same conductor geometry which is used to simulate line currents is also used in CAD with modifications more readily available. It is our hope that the format used here for magnetic fields can be used not only as a means of delivering fields but also as a way by which beam dynamics can suggest correction to the conductor geometry. 5 refs., 70 figs.

  6. Oceanic transform earthquakes with unusual mechanisms or locations - Relation to fault geometry and state of stress in the adjacent lithosphere

    NASA Technical Reports Server (NTRS)

    Wolfe, Cecily J.; Bergman, Eric A.; Solomon, Sean C.

    1993-01-01

    Results are presented of a search for transform earthquakes departing from the pattern whereby they occur on the principal transform displacement zone (PTDZ) and have strike-slip mechanisms consistent with transform-parallel motion. The search was conducted on the basis of source mechanisms and locations taken from the Harvard centroid moment tensor catalog and the bulletin of the International Seismological Center. The source mechanisms and centroid depths of 10 such earthquakes on the St. Paul's, Marathon, Owen, Heezen, Tharp, Menard, and Rivera transforms are determined from inversions of long-period body waveforms. Much of the anomalous earthquake activity on oceanic transforms is associated with complexities in the geometry of the PTDZ or the presence of large structural features that may influence slip on the fault.

  7. Neotectonic reactivation of shear zones and implications for faulting style and geometry in the continental margin of NE Brazil

    NASA Astrophysics Data System (ADS)

    Bezerra, F. H. R.; Rossetti, D. F.; Oliveira, R. G.; Medeiros, W. E.; Neves, B. B. Brito; Balsamo, F.; Nogueira, F. C. C.; Dantas, E. L.; Andrades Filho, C.; Góes, A. M.

    2014-02-01

    The eastern continental margin of South America comprises a series of rift basins developed during the breakup of Pangea in the Jurassic-Cretaceous. We integrated high resolution aeromagnetic, structural and stratigraphic data in order to evaluate the role of reactivation of ductile, Neoproterozoic shear zones in the deposition and deformation of post-rift sedimentary deposits in one of these basins, the Paraíba Basin in northeastern Brazil. This basin corresponds to the last part of the South American continent to be separated from Africa during the Pangea breakup. Sediment deposition in this basin occurred in the Albian-Maastrichtian, Eocene-Miocene, and in the late Quaternary. However, our investigation concentrates on the Miocene-Quaternary, which we consider the neotectonic period because it encompasses the last stress field. This consisted of an E-W-oriented compression and a N-S-oriented extension. The basement of the basin forms a slightly seaward-tilted ramp capped by a late Cretaceous to Quaternary sedimentary cover ~ 100-400 m thick. Aeromagnetic lineaments mark the major steeply-dipping, ductile E-W- to NE-striking shear zones in this basement. The ductile shear zones mainly reactivated as strike-slip, normal and oblique-slip faults, resulting in a series of Miocene-Quaternary depocenters controlled by NE-, E-W-, and a few NW-striking faults. Faulting produced subsidence and uplift that are largely responsible for the present-day morphology of the valleys and tablelands in this margin. We conclude that Precambrian shear zone reactivation controlled geometry and orientation, as well as deformation of sedimentary deposits, until the Neogene-Quaternary.

  8. Morphotectonic, Quaternary and Structural Geology Analyses of the Shallow Geometry of the Mw 6.1, 2009 L'Aquila Earthquake Fault (central Italy): A Missed Opportunity for Surface Faulting Prevention.

    NASA Astrophysics Data System (ADS)

    Pucci, S.; Villani, F.; Civico, R.; Pantosti, D.; Smedile, A.; De Martini, P. M.; Di Naccio, D.; Gueli, A.

    2014-12-01

    The surface-rupturing 2009 L'Aquila earthquake evidenced the limited knowledge of active faults in the Middle Aterno Valley area. Gaps in detailed mapping of Quaternary deposits and tectonic landforms did not trigger researches on active faults, but after the tragic event. We present a morphotectonic study of geometry and evolution of the activated fault system (Paganica-San Demetrio, PSDFS). The LIDAR analysis and field survey yield to a new geological and structural map of the area with an unprecedented detail for the Quaternary deposits. It shows an alluvial depositional system prograding and migrating due to fault system evolution. The normal faults offset both the Quaternary deposits and the bedrock. The structural analysis allows us to recognize two fault systems: (A) NNE- and WNW-trending conjugate extensional system overprinting a strike-slip kinematics and (B) dip-slip NW-trending system. Crosscut relationship suggests that the activity of system B prevails, since Early Pleistocene, on system A, which earlier may have controlled a differently shaped basin. System B is the main responsible for the present-day compound outline of the Middle Aterno Valley, while system A major splays now act as segment boundaries. The long-term expression of B results in prominent fault scarps offsetting Quaternary deposits, dissecting erosional and depositional flat landforms. We retrieved detailed morphologic throws along fault scarps and we dated landforms by 14C, OSL (Optically Stimulated Luminescence), CRN (Cosmogenic Radionuclide) and tephra chronology. We show the persistent role of extensional faulting in dominating Quaternary landform evolution and we estimate slip-rate of the PSDFS at different time-scales. The results support repeated activity of PSDFS for ~20 km total length, thus implying M6.6 maximum expected earthquake. Such an approach should have been applied beforehand for the actual hazard estimation, to trigger, early enough, the adoption of precautionary measures against surface faulting events.

  9. Future earthquake source faults on deep sea-floor around the Boso triple plate junction revealed by tectonic geomorphology using 3D images produced from 150 meter grid DEM

    NASA Astrophysics Data System (ADS)

    Goto, H.; Nakata, T.; Watanabe, M.; Suzuki, Y.; Izumi, N.; Nishizawa, A.; Horiuchi, D.; Kido, Y. N.

    2013-12-01

    Boso triple junction, which is the only example of a triple trench junction on earth, is located off the southeast of Boso peninsula, where the Izu-Bonin trench meets with the Japan trench and the Sagami trench. Boso submarine canyon, which is extended to Katsuuma basin about 7000m deep, forms an incised meander along the north side of Sagami trough. Taito spur separate Katsuuma basin from Bando abyssal basin about 9000m deep, where Japan trench meet with Isu-Bonin trench. In this paper, we present detailed stereo-paired topographic images produced from 0.002 degree (about 150m) DBEM (Digital Bathymetry Model), which processed from the depth sounding data obtained by Japan Coast Guard and JAMSTEC around Boso triple junction. It enables us to observe submarine geomorphology easily and precisely. We identified submarine active faults and other tectonic features related to subduction by using the similar standard for air-photo interpretation of inland active faults. We made more precise submarine active tectonic geomorphological map around Boso triple junction than that by previous workers. Numerous distinct faults on the so-called outer rise associated with subduction of Pacific plate are regarded as normal faulting as widely accepted. While the normal faults on the outer rise are parallel to the trench in the southern part of the Japan trench and the northern part of the Izu-Bonin trench, these normal faults around the east of the triple junction with NNW-SSE extend slightly oblique to the trench. The western margin of Bando abyssal basin is bounded by the thrust faults, which form east-facing 200-500m-high convex scarps associated with raised basin floor to the west of the scarp. These faults also deform Mogi submarine fan surface and uplift to the west along the extension of the scarp. The antecedent valley is extended for about 10km across Taito spur that is an active anticlinal ridge about 1000m high. Katsuura basin is surrounded by terraced former basin floor that is tilted to the west, indicating up-growing of Taito spur. Northeastern part of Izu bar on Philippine Sea plate is characterized by rather smooth extensive convex slope between 1500m-7500m for over 200km long along the trench. On the lower part of the slope below 6000m, several gullies such as Mikura canyon and Kita-Hachijo canyon dissecting the slope forms rapids, probably due to continuous up-warping by subsurface thrusting dipping to the west under the slope. It is noteworthy that we can identify prominent active tectonic features on even very deep sea-floor along the plate boundaries, by using 3D images produced from 150 meter grid DEM.

  10. Examining the Influence of Pore Size Distribution and Geometry on Flow through Unsaturated Peat using 3D Micro-CT Scanning

    Microsoft Academic Search

    F. Rezanezhad; W. L. Quinton; J. S. Price; D. Elrick; T. Elliot; K. Shook

    2009-01-01

    In organic soils, hydraulic conductivity is related to the degree of decomposition and soil compression, which reduce the effective pore diameter and consequently restrict water flow. The unsaturated hydraulic conductivity of complex dual-porosity peat soils is controlled by the peat structure which affects the air-filled porosity, pore size distribution and shape. This study investigates how the size distribution and geometry

  11. Fault geometry and cumulative offsets in the central Coast Ranges, California: Evidence for northward increasing slip along the San Gregorio-San Simeon-Hosgri fault

    USGS Publications Warehouse

    Langenheim, V.E.; Jachens, R.C.; Graymer, R.W.; Colgan, J.P.; Wentworth, C.M.; Stanley, R.G.

    2012-01-01

    Estimates of the dip, depth extent, and amount of cumulative displacement along the major faults in the central California Coast Ranges are controversial. We use detailed aeromagnetic data to estimate these parameters for the San Gregorio–San Simeon–Hosgri and other faults. The recently acquired aeromagnetic data provide an areally consistent data set that crosses the onshore-offshore transition without disruption, which is particularly important for the mostly offshore San Gregorio–San Simeon–Hosgri fault. Our modeling, constrained by exposed geology and in some cases, drill-hole and seismic-reflection data, indicates that the San Gregorio–San Simeon–Hosgri and Reliz-Rinconada faults dip steeply throughout the seismogenic crust. Deviations from steep dips may result from local fault interactions, transfer of slip between faults, or overprinting by transpression since the late Miocene. Given that such faults are consistent with predominantly strike-slip displacement, we correlate geophysical anomalies offset by these faults to estimate cumulative displacements. We find a northward increase in right-lateral displacement along the San Gregorio–San Simeon–Hosgri fault that is mimicked by Quaternary slip rates. Although overall slip rates have decreased over the lifetime of the fault, the pattern of slip has not changed. Northward increase in right-lateral displacement is balanced in part by slip added by faults, such as the Reliz-Rinconada, Oceanic–West Huasna, and (speculatively) Santa Ynez River faults to the east.

  12. Calculating Nuclear Power Plant Vulnerability Using Integrated Geometry and Event/Fault-Tree Models

    SciTech Connect

    Peplow, Douglas E. [Oak Ridge National Laboratory (United States); Sulfredge, C. David [Oak Ridge National Laboratory (United States); Sanders, Robert L. [Oak Ridge National Laboratory (United States); Morris, Robert H. [Oak Ridge National Laboratory (United States); Hann, Todd A. [Defense Threat Reduction Agency (United States)

    2004-01-15

    Since the events of September 11, 2001, the vulnerability of nuclear power plants to terrorist attacks has become a national concern. The results of vulnerability analysis are greatly influenced by the computational approaches used. Standard approximations used in fault-tree analysis are not applicable for attacks, where high component failure probabilities are expected; two methods that do work with high failure probabilities are presented. Different blast modeling approaches can also affect the end results. Modeling the structural details of facility buildings and the geometric layout of components within the buildings is required to yield meaningful results.

  13. Geometry compression

    Microsoft Academic Search

    Michael Deering

    1995-01-01

    This paper introduces the concept of Geometry Compression, al- lowing 3D triangle data to be represented with a factor of 6 to 10 times fewer bits than conventional techniques, with only slight loss- es in object quality. The technique is amenable to rapid decompres- sion in both software and hardware implementations; if 3D render- ing hardware contains a geometry decompression

  14. "Intelligent design" of a 3D reflection survey for the SAFOD drill-hole site

    NASA Astrophysics Data System (ADS)

    Alvarez, G.; Hole, J. A.; Klemperer, S. L.; Biondi, B.; Imhof, M.

    2003-12-01

    SAFOD seeks to better understand the earthquake process by drilling though the San Andreas fault (SAF) to sample an earthquake in situ. To capitalize fully on the opportunities presented by the 1D drill-hole into a complex fault zone we must characterize the surrounding 3D geology at a scale commensurate with the drilling observations, to provide the structural context to extrapolate 1D drilling results along the fault plane and into the surrounding 3D volume. Excellent active-2D and passive-3D seismic observations completed and underway lack the detailed 3D resolution required. Only an industry-quality 3D reflection survey can provide c. 25 m subsurface sample-spacing horizontally and vertically. A 3D reflection survey will provide subsurface structural and stratigraphic control at the 100-m level, mapping major geologic units, structural boundaries, and subsurface relationships between the many faults that make up the SAF fault system. A principal objective should be a reflection-image (horizon-slice through the 3D volume) of the near-vertical fault plane(s) to show variations in physical properties around the drill-hole. Without a 3D reflection image of the fault zone, we risk interpreting drilled anomalies as ubiquitous properties of the fault, or risk missing important anomalies altogether. Such a survey cannot be properly costed or technically designed without major planning. "Intelligent survey design" can minimize source and receiver effort without compromising data-quality at the fault target. Such optimization can in principal reduce the cost of a 3D seismic survey by a factor of two or three, utilizing the known surface logistic constraints, partially-known sub-surface velocity field, and the suite of scientific targets at SAFOD. Our methodology poses the selection of the survey parameters as an optimization process that allows the parameters to vary spatially in response to changes in the subsurface. The acquisition geometry is locally optimized for uniformity of subsurface illumination by a micro-genetic algorithm. We start by accurately establishing the correspondence between the subsurface area of the target reflector (in this case, the steeply-dipping SAF) and the part of the surface area whose sources and receivers contribute to its image using 3D ray-tracing. We then use dense acquisition parameters in that part of the survey area and use standard parameters in the rest of the survey area. This is the key idea that allows us to get optimum image quality with the least acquisition effort. The optimization also requires constraints from structural geologists and from the community who will interpret the results. The most critical parameters to our optimization process are the structural model of the target(s) (depth and geological dips) and the velocity model in the subsurface. We seek community input, and have formed a scientific advisory committee of academic and industry leaders, to help evaluate trade-offs for the community between cost, resolution and volume of the resultant data-set, and to ensure that an appropriate range of piggy-back experiments is developed to utilize the seismic sources available during the 3D experiment. The scientific output of our project will be a community-vetted design for a 3D reflection survey over SAFOD that is technically feasible, cost-effective, and most likely to yield the image and seismic parameter measurements that will best constrain the physical properties of the fault zone and their spatial variation.

  15. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  16. Integrated analysis of seismological, gravimetric and structural data for identification of active faults geometries in Abruzzo and Molise areas (Italy)

    NASA Astrophysics Data System (ADS)

    Gaudiosi, Germana; Nappi, Rosa; Alessio, Giuliana; Porfido, Sabina; Cella, Federico; Fedi, Maurizio; Florio, Giovanni

    2015-04-01

    This paper deals with an interdisciplinary research that has been carried out for more constraining the active faults and their geometry of Abruzzo - Molise areas (Central-Southern Apennines), two of the most active areas from a geodynamic point of view of the Italian Apennines, characterized by the occurrence of intense and widely spread seismic activity. An integrated analysis of structural, seismic and gravimetric (Gaudiosi et al., 2012) data of the area has been carried out through the Geographic Information System (GIS) which has provided the capability for storing and managing large amount of spatial data from different sources. In particular, the analysis has consisted of these main steps: (a) collection and acquisition of aerial photos, numeric cartography, Digital Terrain Model (DTM) data, geophysical data; (b) generation of the vector cartographic database and alpha-numerical data; c) image processing and features classification; d) cartographic restitution and multi-layers representation. In detail three thematic data sets have been generated "fault", "earthquake" and "gravimetric" data sets. The fault Dataset has been compiled by examining and merging the available structural maps, and many recent geological and geophysical papers of literature. The earthquake Dataset has been implemented collecting seismic data by the available historical and instrumental Catalogues and new precise earthquake locations for better constraining existence and activity of some outcropping and buried tectonic structures. Seismic data have been standardized in the same format into the GIS and merged in a final catalogue. For the gravimetric Dataset, the Multiscale Derivative Analysis (MDA) of the gravity field of the area has been performed, relying on the good resolution properties of the Enhanced Horizontal Derivative (EHD) (Fedi et al., 2005). MDA of gravity data has allowed localization of several trends identifying anomaly sources whose presence was not previously detected. The main results of our integrated analysis show a strong correlation among faults, hypocentral location of earthquakes and MDA lineaments from gravity data. Furthermore 2D seismic hypocentral locations together with high-resolution analysis of gravity anomalies have been correlated to estimate the fault systems parameters (strike, dip direction and dip angle) of some structures of the areas, through the application of the DEXP method (Fedi M. and M. Pilkington, 2012). References Fedi M., Cella F., Florio G., Rapolla A.; 2005: Multiscale Derivative Analysis of the gravity and magnetic fields of the Southern Apennines (Italy). In: Finetti I.R. (ed), CROP PROJECT: Deep Seismic Exploration of the Central Mediterranean and Italy, pp. 281-318. Fedi M., Pilkington M.; 2012: Understanding imaging methods for potential field data. Geophysics, 77: G13-G24. Gaudiosi G., Alessio G., Cella F., Fedi M., Florio G., Nappi, R.; 2012: Multiparametric data analysis for seismic sources identification in the Campanian area: merging of seismological, structural and gravimetric data. BGTA,. Vol. 53, n. 3, pp. 283-298.

  17. SU-E-T-342: Use of Patient Geometry Measurements to Predict Dosimetric Gain with VMAT Over 3D for Chestwall and Regional Nodal Radiation

    SciTech Connect

    Dumane, V; Knoll, M; Green, S; Bakst, R [The Mount Sinai Medical Center, NY, NY (United States); Hunt, M [Mem Sloan-Kettering Cancer Ctr, NY, NY (United States); Steinberger, E [The Mount Sinai School of Medicine, NY, NY (United States)

    2014-06-01

    Purpose: To predict the dosimetric gain of VMAT over 3D for the treatment ofchestwall/IMN/supraclavicular nodes using geometric parameters acquired during simulation Methods: CT scans for 20 left and 20 right sided patients were retrospectively analyzed toobtain percent ipsilateral lung volume included in the PWT and supraclavicular fields, central lung depth (CLD), maximum lung depth (MLD), separation, chestwall concavity (defined here as the product of CLD and separation) and the maximum heart depth (MHD). VMAT, PWT and P/E plans were done for each case. The ipsilateral lung V20 Gy and mean, total lung V20 Gy and mean, heart V25 Gy and mean were noted for each plan. Correlation coefficients were obtained and linear regression models were built using data from the above training set of patients and then tested on 4 new patients. Results: The decrease in ipsilateral lung V20 Gy, total lung V20 Gy, ipsilateral lung mean and total lung mean with VMAT over PWT significantly (p<0.05) correlated with the percent volume of ipsilateral lung included in the PWT and supraclavicular fields with correlation coefficient values of r = 0.83, r = 0.77, r = 0.78 and r = 0.75 respectively. Significant correlations were also found between MHD and the decrease in heart V25 Gy and mean of r = 0.77 and r = 0.67 respectively. Dosimetric improvement with VMAT over P/E plans showed no correlation to any of the geometric parameters investigated in this study. The dosimetric gain predicted for the 4 test cases by the linear regression models given their respective percent ipsilateral lung volumes fell within the 95% confidence intervals around the best regression fit. Conclusion: The percent ipsilateral lung volume appears to be a strong predictor of the dosimetric gain on using VMAT over PWT apriori.

  18. Direct measurements of dust attenuation in z ? 1.5 star-forming galaxies from 3D-HST: Implications for dust geometry and star formation rates

    SciTech Connect

    Price, Sedona H.; Kriek, Mariska [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Brammer, Gabriel B. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Conroy, Charlie [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Schreiber, Natascha M. Förster; Wuyts, Stijn [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Franx, Marijn; Fumagalli, Mattia [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Lundgren, Britt [Department of Astronomy, University of Wisconsin, 475 N Charter Street, Madison, WI 53706 (United States); Momcheva, Ivelina; Nelson, Erica J.; Van Dokkum, Pieter G. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Skelton, Rosalind E. [South African Astronomical Observatory, P.O. Box 9, Observatory 7935 (South Africa); Whitaker, Katherine E., E-mail: sedona@berkeley.edu [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States)

    2014-06-10

    The nature of dust in distant galaxies is not well understood, and until recently few direct dust measurements have been possible. We investigate dust in distant star-forming galaxies using near-infrared grism spectra of the 3D-HST survey combined with archival multi-wavelength photometry. These data allow us to make a direct comparison between dust around star-forming regions (A {sub V,} {sub H} {sub II}) and the integrated dust content (A {sub V,} {sub star}). We select a sample of 163 galaxies between 1.36 ? z ? 1.5 with H? signal-to-noise ratio ?5 and measure Balmer decrements from stacked spectra to calculate A {sub V,} {sub H} {sub II}. First, we stack spectra in bins of A {sub V,} {sub star}, and find that A {sub V,} {sub H} {sub II} = 1.86 A {sub V,} {sub star}, with a significance of ? = 1.7. Our result is consistent with the two-component dust model, in which galaxies contain both diffuse and stellar birth cloud dust. Next, we stack spectra in bins of specific star formation rate (log SSFR), star formation rate (log SFR), and stellar mass (log M {sub *}). We find that on average A {sub V,} {sub H} {sub II} increases with SFR and mass, but decreases with increasing SSFR. Interestingly, the data hint that the amount of extra attenuation decreases with increasing SSFR. This trend is expected from the two-component model, as the extra attenuation will increase once older stars outside the star-forming regions become more dominant in the galaxy spectrum. Finally, using Balmer decrements we derive dust-corrected H? SFRs, and find that stellar population modeling produces incorrect SFRs if rapidly declining star formation histories are included in the explored parameter space.

  19. Geometry, slip distribution, and kinematics of surface rupture on the Sakarya fault segment during the 17 August 1999 ?zmit, Turkey, earthquake

    USGS Publications Warehouse

    Langridge, R.M.; Stenner, H.D.; Fumal, T.E.; Christofferson, S.A.; Rockwell, T.K.; Hartleb, R.D.; Bachhuber, J.; Barka, A.A.

    2002-01-01

    The Mw 7.4 17 August 1999 ?zmit earthquake ruptured five major fault segments of the dextral North Anatolian Fault Zone. The 26-km-long, N86°W-trending Sakarya fault segment (SFS) extends from the Sapanca releasing step-over in the west to near the town of Akyazi in the east. The SFS emerges from Lake Sapanca as two distinct fault traces that rejoin to traverse the Adapazari Plain to Akyazi. Offsets were measured across 88 cultural and natural features that cross the fault, such as roads, cornfield rows, rows of trees, walls, rails, field margins, ditches, vehicle ruts, a dike, and ground cracks. The maximum displacement observed for the ?zmit earthquake (?5.1 m) was encountered on this segment. Dextral displacement for the SFS rises from less than 1 m at Lake Sapanca to greater than 5 m near Arifiye, only 3 km away. Average slip decreases uniformly to the east from Arifiye until the fault steps left from Sagir to Kazanci to the N75°W, 6-km-long Akyazi strand, where slip drops to less than 1 m. The Akyazi strand passes eastward into the Akyazi Bend, which consists of a high-angle bend (18°-29°) between the Sakarya and Karadere fault segments, a 6-km gap in surface rupture, and high aftershock energy release. Complex structural geometries exist between the ?zmit, Düzce, and 1967 Mudurnu fault segments that have arrested surface ruptures on timescales ranging from 30 sec to 88 days to 32 yr. The largest of these step-overs may have acted as a rupture segmentation boundary in previous earthquake cycles.

  20. Co-seismic fault geometry and slip distribution of the 26 December 2004, giant Sumatra-Andaman earthquake constrained by GPS, coral reef, and remote sensing data

    NASA Astrophysics Data System (ADS)

    Wan, Yongge; Shen, Zheng-kang; Wang, Min; Zeng, Yuehua; Huang, Jichao; Li, Xiang; Cui, Huawei; Gao, Xiwei

    2015-05-01

    We analyze co-seismic displacement field of the 26 December 2004, giant Sumatra-Andaman earthquake derived from Global Position System observations, geological vertical measurement of coral head, and pivot line observed through remote sensing. Using the co-seismic displacement field and AK135 spherical layered Earth model, we invert co-seismic slip distribution along the seismic fault. We also search the best fault geometry model to fit the observed data. Assuming that the dip angle linearly increases in downward direction, the postfit residual variation of the inversed geometry model with dip angles linearly changing along fault strike are plotted. The geometry model with local minimum misfits is the one with dip angle linearly increasing along strike from 4.3o in top southernmost patch to 4.5o in top northernmost path and dip angle linearly increased. By using the fault shape and geodetic co-seismic data, we estimate the slip distribution on the curved fault. Our result shows that the earthquake ruptured ~200-km width down to a depth of about 60 km. 0.5-12.5 m of thrust slip is resolved with the largest slip centered around the central section of the rupture zone 7ºN-10ºN in latitude. The estimated seismic moment is 8.2 × 1022 N m, which is larger than estimation from the centroid moment magnitude (4.0 × 1022 N m), and smaller than estimation from normal-mode oscillation data modeling (1.0 × 1023 N m).

  1. PCA-based 3D Face Photography

    Microsoft Academic Search

    Jesus P. Mena-chalco; Ives Macedo; Luiz Velho; Roberto Marcondes Cesar Jr

    2008-01-01

    This paper presents a 3D face photography system based on a small set of training facial range images. The training set is composed by 2D texture and 3D range images (i.e. geometry) of a single subject with different facial expressions. The basic idea behind the method is to create texture and geometry spaces based on the training set and transformations

  2. Temporal variation in the geometry of a strike–slip fault zone: Examples from the Dead Sea Transform

    Microsoft Academic Search

    Shmuel Marco

    2007-01-01

    The location of the active fault strands along the Dead Sea Transform fault zone (DST) changed through time. In the western margins of Dead Sea basin, the early activity began a few kilometers west of the preset shores and moved toward the center of the basin in four stages. Similar centerward migration of faulting is apparent in the Hula Valley

  3. 3-D seismology in the Arabian Gulf

    SciTech Connect

    Al-Husseini, M. [Gulf PetroLink, Manama (Bahrain); Chimblo, R. [Saudi Aramco, Dhahran (Saudi Arabia)

    1995-08-01

    Since 1977 when Aramco and GSI (Geophysical Services International) pioneered the first 3-D seismic survey in the Arabian Gulf, under the guidance of Aramco`s Chief Geophysicist John Hoke, 3-D seismology has been effectively used to map many complex subsurface geological phenomena. By the mid-1990s extensive 3-D surveys were acquired in Abu Dhabi, Oman, Qatar and Saudi Arabia. Also in the mid-1990`s Bahrain, Kuwait and Dubai were preparing to record surveys over their fields. On the structural side 3-D has refined seismic maps, focused faults and fractures systems, as well as outlined the distribution of facies, porosity and fluid saturation. In field development, 3D has not only reduced drilling costs significantly, but has also improved the understanding of fluid behavior in the reservoir. In Oman, Petroleum Development Oman (PDO) has now acquired the first Gulf 4-D seismic survey (time-lapse 3D survey) over the Yibal Field. The 4-D survey will allow PDO to directly monitor water encroachment in the highly-faulted Cretaceous Shu`aiba reservoir. In exploration, 3-D seismology has resolved complex prospects with structural and stratigraphic complications and reduced the risk in the selection of drilling locations. The many case studies from Saudi Arabia, Oman, Qatar and the United Arab Emirates, which are reviewed in this paper, attest to the effectiveness of 3D seismology in exploration and producing, in clastics and carbonates reservoirs, and in the Mesozoic and Paleozoic.

  4. Efficient Numerical Procedure for Reduction of Computation Time in BIEM for Elastodynamic Analysis of Nonplanar Faults

    Microsoft Academic Search

    N. Kame

    2003-01-01

    Recent progress in boundary integral equation method (BIEM) have been enabled us to analyze dynamic rupture process on fully non-planar fault geometry, such as steps, bendings, and branchings, in 2D (Kame and Yamashita, 1999) and 3D (Aochi, Fukuyama and Matsu'ura 2000; Fukuyama, Tada and Shibazaki 2002, Eos Trans. AGU 83(47)). In space-time boundary integral formulations, the stress on the fault

  5. Testing long-period ground-motion simulations of scenario earthquakes using the Mw 7.2 El Mayor-Cucapah mainshock: Evaluation of finite-fault rupture characterization and 3D seismic velocity models

    USGS Publications Warehouse

    Graves, Robert W.; Aagaard, Brad T.

    2011-01-01

    Using a suite of five hypothetical finite-fault rupture models, we test the ability of long-period (T>2.0 s) ground-motion simulations of scenario earthquakes to produce waveforms throughout southern California consistent with those recorded during the 4 April 2010 Mw 7.2 El Mayor-Cucapah earthquake. The hypothetical ruptures are generated using the methodology proposed by Graves and Pitarka (2010) and require, as inputs, only a general description of the fault location and geometry, event magnitude, and hypocenter, as would be done for a scenario event. For each rupture model, two Southern California Earthquake Center three-dimensional community seismic velocity models (CVM-4m and CVM-H62) are used, resulting in a total of 10 ground-motion simulations, which we compare with recorded ground motions. While the details of the motions vary across the simulations, the median levels match the observed peak ground velocities reasonably well, with the standard deviation of the residuals generally within 50% of the median. Simulations with the CVM-4m model yield somewhat lower variance than those with the CVM-H62 model. Both models tend to overpredict motions in the San Diego region and underpredict motions in the Mojave desert. Within the greater Los Angeles basin, the CVM-4m model generally matches the level of observed motions, whereas the CVM-H62 model tends to overpredict the motions, particularly in the southern portion of the basin. The variance in the peak velocity residuals is lowest for a rupture that has significant shallow slip (<5 km depth), whereas the variance in the residuals is greatest for ruptures with large asperities below 10 km depth. Overall, these results are encouraging and provide confidence in the predictive capabilities of the simulation methodology, while also suggesting some regions in which the seismic velocity models may need improvement.

  6. Inferred fault geometry and slip distribution of the 2010 Jiashian, Taiwan, earthquake is consistent with a thick-skinned deformation model

    NASA Astrophysics Data System (ADS)

    Ching, Kuo-En; Johnson, Kaj M.; Rau, Ruey-Juin; Chuang, Ray Y.; Kuo, Long-Chen; Leu, Pei-Ling

    2011-01-01

    We invert measurements of coseismic displacements from 139 continuously recorded GPS sites from the 2010, Jiashian, Taiwan earthquake to solve for fault geometry and slip distribution using an elastic uniform stress drop inversion. The earthquake occurred at a depth of ~ 23 km in an area between the Western Foothills fold-and-thrust belt and the crystalline high mountains of the Central Range, providing an opportunity to examine the deep fault structure under Taiwan. The inferred rupture plane is oblique to the prominent orientation of thrust faults and parallel to several previously recognized NW-striking transfer zones that appear to connect stepping thrusts. We find that a fault striking 318°-344° with dip of 26°-41° fits the observations well with oblique reverse-sinistral slip under a low stress drop of about 0.5 MPa. The derived geodetic moment of 2.92 × 1018 N-m is equivalent to a Mw = 6.24 earthquake. Coseismic slip is largely concentrated within a circular patch with a 10-km radius at the depth between 10 and 24 km and maximum slip of 190 mm. We suggest this earthquake ruptured the NW-striking Chishan transfer fault zone, which we interpret as a listric NE-dipping lateral ramp with oblique slip connecting stepping thrust faults (ramps). The inferred slip on the lateral ramp is considerably deeper than the 7-15 km deep detachment identified in previous studies of western Taiwan. We infer an active basal detachment under western Taiwan at a depth of at least ~ 20-23 km based on these inversion results. The earthquake may have nucleated at the base of the lateral ramp near the intersection with the basal detachment. Coulomb stress change calculations suggest that this earthquake moved several NE-striking active thrust faults in western Taiwan nearer to failure.

  7. Geometry, numerical models and revised slip rate for the Reelfoot fault and trishear fault-propagation fold, New Madrid seismic zone

    E-print Network

    Mueller, Karl

    -propagation fold, New Madrid seismic zone Jocasta Championa , Karl Muellera,*, Alex Tatea , Margaret Guccioneb in the New Madrid seismic zone (John- ston and Schweig, 1996). We term the Reelfoot fault as the active

  8. Regional and reservoir-scale analysis of fault systems and structural development of Pagerungan Gas Field, East Java Sea, Indonesia

    SciTech Connect

    Davies, R.K.; Medwedeff, D.A. [Arco Exploration and Production Technology, Plano, TX (United States)

    1996-12-31

    Pagerungan gas field lies on a complexly faulted and folded anticline just north of the major Sakala-Paliat Fault System (SPFS) offshore Bali. The Eocene clastic reservoir is affected by two generations of faults: Eocene normal and Neogene compressional faults. Fault geometry, timing and connectivity is determined by combining regional and field-scale methods. Restored regional structure maps and sections indicate the field is located on the L. Eocene, footwall-paleo-high of the south-dipping SPFS. Within the field, smaller normal faults nucleated sub-parallel to the SPFS with both synthetic and antithetic dips. Neogene to Present compression folded the strata creating closure in the field, reversed slip on selected preexisting normal faults, and nucleated new reverse fault sets. Some normal faults are completely inverted, others have net normal offset after some reverse slip, and still others are not reactivated. Reverse faults strike sub-parallel to earlier formed normal faults. The eastern and western parts of the field are distinguished by the style and magnitude of early compressional deformation. 3D seismic analysis indicates the geometry of reservoir faults is similar to the regional fault systems: sub-parallel segments share displacement at their terminations either by distributed deformation in the rock between adjacent terminations or through short cross-faults oriented at a high angle to the principal fault sets. Anomalous trends in the contours of throw projected onto fault surfaces predict the connectivity of complex fault patterns. Integration of regional and field-scale analysis provides the most accurate prediction of fault geometry and lays the foundation for field development.

  9. Regional and reservoir-scale analysis of fault systems and structural development of Pagerungan Gas Field, East Java Sea, Indonesia

    SciTech Connect

    Davies, R.K.; Medwedeff, D.A. (Arco Exploration and Production Technology, Plano, TX (United States))

    1996-01-01

    Pagerungan gas field lies on a complexly faulted and folded anticline just north of the major Sakala-Paliat Fault System (SPFS) offshore Bali. The Eocene clastic reservoir is affected by two generations of faults: Eocene normal and Neogene compressional faults. Fault geometry, timing and connectivity is determined by combining regional and field-scale methods. Restored regional structure maps and sections indicate the field is located on the L. Eocene, footwall-paleo-high of the south-dipping SPFS. Within the field, smaller normal faults nucleated sub-parallel to the SPFS with both synthetic and antithetic dips. Neogene to Present compression folded the strata creating closure in the field, reversed slip on selected preexisting normal faults, and nucleated new reverse fault sets. Some normal faults are completely inverted, others have net normal offset after some reverse slip, and still others are not reactivated. Reverse faults strike sub-parallel to earlier formed normal faults. The eastern and western parts of the field are distinguished by the style and magnitude of early compressional deformation. 3D seismic analysis indicates the geometry of reservoir faults is similar to the regional fault systems: sub-parallel segments share displacement at their terminations either by distributed deformation in the rock between adjacent terminations or through short cross-faults oriented at a high angle to the principal fault sets. Anomalous trends in the contours of throw projected onto fault surfaces predict the connectivity of complex fault patterns. Integration of regional and field-scale analysis provides the most accurate prediction of fault geometry and lays the foundation for field development.

  10. Europeana and 3D

    NASA Astrophysics Data System (ADS)

    Pletinckx, D.

    2011-09-01

    The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.

  11. On the climate-geometry imbalance, response time and volume-area scaling of an alpine glacier: insights from a 3-D flow model applied to Vadret da Morteratsch

    NASA Astrophysics Data System (ADS)

    Zekollari, Harry; Huybrechts, Philippe

    2015-04-01

    The worldwide mass loss of glaciers in the coming century will not only result from additional warming, but will also be a consequence of the glacier's response to the 20th century warming. This is a consequence of their response time, as a change in mass balance needs time to translate into a change in glacier geometry. A better insight in the response time of glaciers is therefore crucial to improve future glacier projections. Our knowledge on glacier response times mainly relies on analytical methods, conceptual models and numerical experiments with idealized glacier setups. Here we present for the first time a detailed 3-D ice flow modelling study on the response time of an individual glacier. The modelling relies on an extensive observational dataset and on ice flow and mass balance models that are calibrated and validated against different sources. This unique setup allows us to analyse the response time of an alpine glacier in a realistic setting and look at the different factors that influence it, with a particular focus on those not taken into account in analytical methods and conceptual models. We start by analysing the present-day and past climate-geometry imbalance. Subsequently we focus on the response time and the effect of the magnitude and spatial distribution of the forcing, which effects have hitherto not been investigated. Response times from our numerical simulation are compared with analytical methods and also the influence of the glacier size is examined. Finally we discuss the applicability of the volume-area scaling, suggest how the glacier slope can be incorporated, and analyse the impact of the climate-geometry imbalance on this relationship.

  12. Constraining the slip distribution and fault geometry of the Mw 7.9, 3 November 2002, Denali fault earthquake with Interferometric Synthetic Aperture Radar and Global Positioning System data

    USGS Publications Warehouse

    Wright, T.J.; Lu, Zhiming; Wicks, C.

    2004-01-01

    The Mw 7.9, Denali fault earthquake (DFE) is the largest continental strike-slip earthquake to occur since the development of Interferometric Synthetic Aperture Radar (InSAR). We use five interferograms, constructed using radar images from the Canadian Radarsat-1 satellite, to map the surface deformation at the western end of the fault rupture. Additional geodetic data are provided by displacements observed at 40 campaign and continuous Global Positioning System (GPS) sites. We use the data to determine the geometry of the Susitna Glacier fault, thrusting on which initiated the DFE, and to determine a slip model for the entire event that is consistent with both the InSAR and GPS data. We find there was an average of 7.3 ?? 0.4 m slip on the Susitna Glacier fault, between 1 and 9.5 km depth on a 29 km long fault that dips north at 41 ?? 0.7?? and has a surface projection close to the mapped rupture. On the Denali fault, a simple model with large slip patches finds a maximum of 8.7 ?? 0.7 m of slip between the surface and 14.3 ?? 0.2 km depth. A more complex distributed slip model finds a peak of 12.5 ?? 0.8 m in the upper 4 km, significantly higher than the observed surface slip. We estimate a geodetic moment of 670 ?? 10 ?? 10 18 N m (Mw 7.9), consistent with seismic estimates. Lack of preseismic data resulted in an absence of InSAR coverage for the eastern half of the DFE rupture. A dedicated geodetic InSAR mission could obviate coverage problems in the future.

  13. 3D Gradient coil design – Toroidal surfaces

    Microsoft Academic Search

    Peter T. While; Larry K. Forbes; Stuart Crozier

    2009-01-01

    Gradient coil design typically involves optimisation of current densities or coil windings on familiar cylindrical, planar, spherical or conical surfaces. In this paper, an analytic inverse method is presented for the theoretical design of toroidal transverse gradient coils. This novel geometry is based on previous work involving a 3D current density solution, in which the precise geometry of the gradient

  14. 3D Gradient coil design - Toroidal surfaces

    Microsoft Academic Search

    Peter T. While; Larry K. Forbes; Stuart Crozier

    2009-01-01

    Gradient coil design typically involves optimisation of current densities or coil windings on familiar cylindrical, planar, spherical or conical surfaces. In this paper, an analytic inverse method is presented for the theoretical design of toroidal transverse gradient coils. This novel geometry is based on previous work involving a 3D current density solution, in which the precise geometry of the gradient

  15. Insights Into the Geometries and Mechanics of Active Folding Above Blind-Thrust Faults From Discrete Element Models

    Microsoft Academic Search

    N. P. Benesh; A. Plesch; J. H. Shaw; E. Frost

    2006-01-01

    Using the discrete element method, we examine the nature of fault-bend fold development in sedimentary growth and pre-growth layers above a sharp anticlinal bend in a blind thrust fault. Our models were composed of tens of thousands of numerical disks bonded together to form a coherent package of hangingwall pre-growth sedimentary strata overlying a fixed fault surface. This pre-growth package,

  16. 3D Model to 3D Print

    Microsoft Academic Search

    Sandeep Singh

    \\u000a It’s time to bring the ideas you’ve learned in the first couple of chapters and develop a model in SketchUp for 3D printing\\u000a in Shapeways. The goal of this chapter is to get you acquainted with all the basic steps of developing a model for 3D printing.\\u000a You’ll start this chapter off with a brainstorming session where you develop sketches

  17. Intraoral 3D scanner

    NASA Astrophysics Data System (ADS)

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther

    2007-09-01

    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  18. Alterations in regional vascular geometry produced by theoretical stent implantation influence distributions of wall shear stress: analysis of a curved coronary artery using 3D computational fluid dynamics modeling

    PubMed Central

    LaDisa, John F; Olson, Lars E; Douglas, Hettrick A; Warltier, David C; Kersten, Judy R; Pagel, Paul S

    2006-01-01

    Background The success of stent implantation in the restoration of blood flow through areas of vascular narrowing is limited by restenosis. Several recent studies have suggested that the local geometric environment created by a deployed stent may influence regional blood flow characteristics and alter distributions of wall shear stress (WSS) after implantation, thereby rendering specific areas of the vessel wall more susceptible to neointimal hyperplasia and restenosis. Stents are most frequently implanted in curved vessels such as the coronary arteries, but most computational studies examining blood flow patterns through stented vessels conducted to date use linear, cylindrical geometric models. It appears highly probable that restenosis occurring after stent implantation in curved arteries also occurs as a consequence of changes in fluid dynamics that are established immediately after stent implantation. Methods In the current investigation, we tested the hypothesis that acute changes in stent-induced regional geometry influence distributions of WSS using 3D coronary artery CFD models implanted with stents that either conformed to or caused straightening of the primary curvature of the left anterior descending coronary artery. WSS obtained at several intervals during the cardiac cycle, time averaged WSS, and WSS gradients were calculated using conventional techniques. Results Implantation of a stent that causes straightening, rather than conforms to the natural curvature of the artery causes a reduction in the radius of curvature and subsequent increase in the Dean number within the stented region. This straightening leads to modest skewing of the velocity profile at the inlet and outlet of the stented region where alterations in indices of WSS are most pronounced. For example, time-averaged WSS in the proximal portion of the stent ranged from 8.91 to 11.7 dynes/cm2 along the pericardial luminal surface and 4.26 to 4.88 dynes/cm2 along the myocardial luminal surface of curved coronary arteries as compared to 8.31 dynes/cm2 observed throughout the stented region of a straight vessel implanted with an equivalent stent. Conclusion The current results predicting large spatial and temporal variations in WSS at specific locations in curved arterial 3D CFD simulations are consistent with clinically observed sites of restenosis. If the findings of this idealized study translate to the clinical situation, the regional geometry established immediately after stent implantation may predispose portions of the stented vessel to a higher risk of neointimal hyperplasia and subsequent restenosis. PMID:16780592

  19. Morphometric and geometric characterization of normal faults on Mars

    NASA Astrophysics Data System (ADS)

    Vaz, David A.; Spagnuolo, Mauro G.; Silvestro, Simone

    2014-09-01

    Using three different approaches (fault plane fitting, 3D crater rim palinspatic restorations and fault scarps morphometric analysis) we investigate the geometry and degradation history of Martian normal faults in two distinct areas. The three independent methods produce similar results, indicating that the average dip angle of the normal faults on these two locations is probably below the value that is usually assumed for Mars (?60°). Our best estimate for this average dip angle is 46.8±9.8°, which is a value comparable with the mean dip angle inferred on Earth for seismically active normal faults. This lower average dip angle implies that all the rift strain estimates performed until now might be underestimated. From the comparative analysis of the two faulted regions (Phlegethon Catena and Claritas Fossae), we show that local and regional dip variabilities may exist on Mars. This reinforces the idea that the amount of extension associated with Martian rifts must be reconsidered. We also demonstrate the advantages of performing a comparative morphometric analysis of fault scarps. This approach enables the reconstruction of the faults scarps degradation history and can be used to evaluate how environmental conditions changed through time. After modeling the degradation of the fault scarps at the two sites we conclude that the observed morphometric variations are mainly due to the different faulting ages in an environment characterized by low scarp degradation rates (4×10-3 m/kyr) over the last 3 Ga.

  20. Integrating 3D seismic curvature and curvature gradient attributes for fracture characterization: Methodologies and interpretational implications

    SciTech Connect

    Gao, Dengliang

    2013-03-01

    In 3D seismic interpretation, curvature is a popular attribute that depicts the geometry of seismic reflectors and has been widely used to detect faults in the subsurface; however, it provides only part of the solutions to subsurface structure analysis. This study extends the curvature algorithm to a new curvature gradient algorithm, and integrates both algorithms for fracture detection using a 3D seismic test data set over Teapot Dome (Wyoming). In fractured reservoirs at Teapot Dome known to be formed by tectonic folding and faulting, curvature helps define the crestal portion of the reservoirs that is associated with strong seismic amplitude and high oil productivity. In contrast, curvature gradient helps better define the regional northwest-trending and the cross-regional northeast-trending lineaments that are associated with weak seismic amplitude and low oil productivity. In concert with previous reports from image logs, cores, and outcrops, the current study based on an integrated seismic curvature and curvature gradient analysis suggests that curvature might help define areas of enhanced potential to form tensile fractures, whereas curvature gradient might help define zones of enhanced potential to develop shear fractures. In certain fractured reservoirs such as at Teapot Dome where faulting and fault-related folding contribute dominantly to the formation and evolution of fractures, curvature and curvature gradient attributes can be potentially applied to differentiate fracture mode, to predict fracture intensity and orientation, to detect fracture volume and connectivity, and to model fracture networks.

  1. Geometry of the Nojima fault at Nojima-Hirabayashi, Japan - I. A simple damage structure inferred from borehole core permeability

    USGS Publications Warehouse

    Lockner, D.A.; Tanaka, H.; Ito, H.; Ikeda, R.; Omura, K.; Naka, H.

    2009-01-01

    The 1995 Kobe (Hyogo-ken Nanbu) earthquake, M = 7.2, ruptured the Nojima fault in southwest Japan. We have studied core samples taken from two scientific drillholes that crossed the fault zone SW of the epicentral region on Awaji Island. The shallower hole, drilled by the Geological Survey of Japan (GSJ), was started 75 m to the SE of the surface trace of the Nojima fault and crossed the fault at a depth of 624 m. A deeper hole, drilled by the National Research Institute for Earth Science and Disaster Prevention (NIED) was started 302 m to the SE of the fault and crossed fault strands below a depth of 1140 m. We have measured strength and matrix permeability of core samples taken from these two drillholes. We find a strong correlation between permeability and proximity to the fault zone shear axes. The half-width of the high permeability zone (approximately 15 to 25 m) is in good agreement with the fault zone width inferred from trapped seismic wave analysis and other evidence. The fault zone core or shear axis contains clays with permeabilities of approximately 0.1 to 1 microdarcy at 50 MPa effective confining pressure (10 to 30 microdarcy at in situ pressures). Within a few meters of the fault zone core, the rock is highly fractured but has sustained little net shear. Matrix permeability of this zone is approximately 30 to 60 microdarcy at 50 MPa effective confining pressure (300 to 1000 microdarcy at in situ pressures). Outside this damage zone, matrix permeability drops below 0.01 microdarcy. The clay-rich core material has the lowest strength with a coefficient of friction of approximately 0.55. Shear strength increases with distance from the shear axis. These permeability and strength observations reveal a simple fault zone structure with a relatively weak fine-grained core surrounded by a damage zone of fractured rock. In this case, the damage zone will act as a high-permeability conduit for vertical and horizontal flow in the plane of the fault. The fine-grained core region, however, will impede fluid flow across the fault. ?? Birkh??user Verlag, Basel 2009.

  2. The quaternion Bingham Distribution, 3D object detection, and dynamic manipulation

    E-print Network

    Glover, Jared Marshall

    2014-01-01

    Over the past few years, the field of robotic computer vision has undergone a 3-D revolution. One of the biggest challenges in dealing with 3-D geometry lies in appropriately handling 3-D rotational data. To specify "where" ...

  3. Low-angle extensional faulting, reactivated mylonites, and seismic reflection geometry of the Newark basin margin in eastern Pennsylvania

    SciTech Connect

    Ratcliffe, N.M.; Burton, W.C.; D'Angelo, R.M.; Costain, J.K.

    1986-09-01

    Low-angle 25/sup 0/ to 35/sup 0/ dips have been determined for the border fault of the Newark basin near Riegelsville, Pennsylvania, on the basis of a Vibroseis profile and two continuously cored drill holes across faults at the basin margin. A group of moderately strong planar reflections in a zone 0.5 km thick in gneiss and carbonate rocks of the footwall block coincides with the updip projection of imbricate fault slices and mylonites associated with the Musconetcong thrust system of Drake et al. (1967). Contrasts in acoustic impedance among mylonitic dolostone and mylonitic gneiss and their protoliths, determined from measurements on samples from a third cored hole, are sufficiently large to account for reflections seen in the footwall block. Analysis of drill core and surface outcrops supports the conclusion that low-angle extensional faulting in the early Mesozoic was localized by reactivation of Paleozoic imbricate thrust faults in the basement rocks. Extension in the northwest-southeast quadrant was approximately perpendicular to the strike of the ancient thrust faults in eastern Pennsylvania. The data presented here are the most explicit three-dimensional information obtained thus far in the eastern US in support of the concept of fault reactivation in controlling formation of early Mesozoic extensional basins.

  4. Dynamic evolution of a fault system through interactions between fault segments

    Microsoft Academic Search

    Ryosuke Ando; Taku Tada; Teruo Yamashita

    2004-01-01

    We simulate the dynamic evolution process of fault system geometry considering interactions between fault segments. We calculate rupture propagation using an elastodynamic boundary integral equation method (BIEM) in which the trajectory of a fault tip is dynamically self-chosen. We consider a system of two noncoplanar fault segments: a preexisting main fault segment (fault 1) and a subsidiary one (fault 2)

  5. Fault Geometry and Active Stress from Earthquakes and Field Geology Data Analysis: The Colfiorito 1997 and L'Aquila 2009 Cases (Central Italy)

    NASA Astrophysics Data System (ADS)

    Ferrarini, F.; Lavecchia, G.; de Nardis, R.; Brozzetti, F.

    2015-05-01

    The fault segmentation pattern and the regional stress tensor acting since the Early Quaternary in the intra-Apennine area of central Italy was constrained by integrating two large geological and seismological fault-slip data sets collected for the areas struck by the two most energetic seismic sequences of the last 15 years (Colfiorito 1997, M w 6.0 and L'Aquila 2009, M w 6.1). The integrated analysis of the earthquake fault association and the reconstruction of the 3D shape of the seismogenic sources were exploited to identify homogeneous seismogenic volumes associated with subsets of geological and focal mechanism data. The independent analysis of geological and seismological data allowed us to observe and highlight similarities between the attitude of the long-term (e.g., Quaternary) and the instantaneous present-day (seismogenic) extensional deformations and to reveal their substantial coaxiality. Coherently, with the results from the kinematic analysis, the stress field inversion also noted a prevailing tensional seismotectonic regime associated with a subhorizontal, NE-SW, minimum stress axis. A minor, very local, and shallow (<5 km) strike-slip component of the stress field was observed in the Colfiorito sector, where an inherited N-S oriented right-lateral fault was reactivated with sinistral kinematics. Instead, an almost total absence of strike-slip solutions was observed in the L'Aquila area. These results do not agree with those indicating Quaternary regional strike-slip regimes or wide areas characterized by strike-slip deformation during the Colfiorito and L'Aquila seismic sequences.

  6. Multiscale Representation and Compression of 3-D Point Data

    Microsoft Academic Search

    Sung-Bum Park; Sang-Uk Lee

    2009-01-01

    A compact representation scheme is presented for 3-D point data. To describe underlying surface from raw point samples, we dyadically divide a 3-D domain enclosing whole points. Then, local points in each cube are approximated by a plane patch, yielding a multiscale representation of 3-D surface. To reduce the redundancy between different scale models, the geometry innovation is evaluated between

  7. 3D Motifs

    Microsoft Academic Search

    Elaine C. Meng; Benjamin J. Polacco; Patricia C. Babbitt

    Three-dimensional (3D) motifs are patterns of local structure associated with function, typically based on residues in binding\\u000a or catalytic sites. Protein structures of unknown function can be annotated by comparing them to known 3D motifs. Many methods\\u000a have been developed for identifying 3D motifs and for searching structures for their occurrence. Approaches vary in the type\\u000a and amount of input

  8. 3D detectors - a new direction for Medipix

    Microsoft Academic Search

    V. A. Wright; A. Blue; M. Horn; I. Johnston; E. Koskiahde; L. Lea; J. Melone; S. Nenonen; V. O’Shea; M. Rahman; P. Roy; K. Smith

    2004-01-01

    The 3D sensor geometry has many advantages over the traditional planar sensor geometry, including improvements in radiation tolerance (Nucl. Instr and Meth. A 509 (2003) 132) and charge collection time. A 3D sensor compatible with the Medipix1 chip is presented. Preliminary electrical measurements have been made on a test sample fabricated with Schottky contacts and simulations using the ISE package

  9. Gravity and magnetic expression of the San Leandro gabbro with implications for the geometry and evolution of the Hayward Fault zone, northern California

    USGS Publications Warehouse

    Ponce, D.A.; Hildenbrand, T.G.; Jachens, R.C.

    2003-01-01

    The Hayward Fault, one of the most hazardous faults in northern California, trends north-northwest and extends for about 90 km along the eastern San Francisco Bay region. At numerous locations along its length, distinct and elongate gravity and magnetic anomalies correlate with mapped mafic and ultramafic rocks. The most prominent of these anomalies reflects the 16-km-long San Leandro gabbroic block. Inversion of magnetic and gravity data constrained with physical property measurements is used to define the subsurface extent of the San Leandro gabbro body and to speculate on its origin and relationship to the Hayward Fault Zone. Modeling indicates that the San Leandro gabbro body is about 3 km wide, dips about 75??-80?? northeast, and extends to a depth of at least 6 km. One of the most striking results of the modeling, which was performed independently of seismicity data, is that accurately relocated seismicity is concentrated along the western edge or stratigraphically lower bounding surface of the San Leandro gabbro. The western boundary of the San Leandro gabbro block is the base of an incomplete ophiolite sequence and represented at one time, a low-angle roof thrust related to the tectonic wedging of the Franciscan Complex. After repeated episodes of extension and attenuation, the roof thrust of this tectonic wedge was rotated to near vertical, and in places, the strike-slip Hayward Fault probably reactivated or preferentially followed this pre-existing feature. Because earthquakes concentrate near the edge of the San Leandro gabbro but tend to avoid its interior, we qualitatively explore mechanical models to explain how this massive igneous block may influence the distribution of stress. The microseismicity cluster along the western flank of the San Leandro gabbro leads us to suggest that this stressed volume may be the site of future moderate to large earthquakes. Improved understanding of the three-dimensional geometry and physical properties along the Hayward Fault will provide additional constraints on seismic hazard probability, earthquake modeling, and fault interactions that are applicable to other major strike-slip faults around the world.

  10. PCA-based 3D Face Photography

    Microsoft Academic Search

    Ives Mac; Luiz Velho; Roberto M. Cesar-Jr

    This paper presents a 3D face photography system based on a small set of training facial range images. The training set is composed by 2D texture and 3D range images (i.e. ge- ometry) of a single subject with different facial expressions. The basic idea behind the method is to create texture and geometry spaces based on the training set and

  11. Self-Discovery of Structural Geology Concepts using Interactive 3D Visualization

    NASA Astrophysics Data System (ADS)

    Billen, M. I.; Saunders, J.

    2010-12-01

    Mastering structural geology concepts that depend on understanding three-dimensional (3D) geometries and imagining relationships among unseen subsurface structures are fundamental skills for geologists. Traditionally these skills are developed first, through use of 2D drawings of 3D structures that can be difficult to decipher or 3D physical block models that show only a limited set of relationships on the surfaces of the blocks, followed by application and testing of concepts in field settings. We hypothesize that this learning process can be improved by providing repeated opportunities to evaluate and explore synthetic 3D structures using interactive 3D visualization software. We present laboratory modules designed for undergraduate structural geology curriculum using a self-discovery approach to teach concepts such as: the Rule of V’s, structure separation versus fault slip, and the more general dependence of structural exposure on surface topography. The laboratory modules are structured to allow students to discover and articulate each concept from observations of synthetic data both on traditional maps and using the volume visualization software 3DVisualizer. Modules lead students through exploration of data (e.g., a dipping layered structure exposed in ridge-valley topography or obliquely offset across a fault) by allowing them to interactively view (rotate, pan, zoom) the exposure of structures on topographic surfaces and to toggle on/off the full 3D structure as a transparent colored volume. This tool allows student to easily visually understand the relationships between, for example a dipping structure and its exposure on valley walls, as well as how the structure extends beneath the surface. Using this method gives students more opportunities to build a mental library of previously-seen relationships from which to draw-on when applying concepts in the field setting. These laboratory modules, the data and software are freely available from KeckCAVES.

  12. 3D characterization of a Great Basin geothermal system: Astor Pass, NV

    NASA Astrophysics Data System (ADS)

    Siler, D. L.; Mayhew, B.; Faulds, J. E.

    2012-12-01

    The Great Basin exhibits both anomalously high heat flow (~75±5 mWm-2) and active faulting and extension resulting in robust geothermal activity. There are ~430 known geothermal systems in the Great Basin, with evidence suggesting that undiscovered blind geothermal systems may actually represent the majority of geothermal activity. These systems employ discrete fault intersection/interaction areas as conduits for geothermal circulation. Recent studies show that steeply dipping normal faults with step-overs, fault intersections, accommodation zones, horse-tailing fault terminations and transtensional pull-aparts are the most prominent structural controls of Great Basin geothermal systems. These fault geometries produce sub-vertical zones of high fault and fracture density that act as fluid flow conduits. Structurally controlled fluid flow conduits are further enhanced when critically stressed with respect to the ambient stress conditions. The Astor Pass blind geothermal system, northwestern Nevada, lies along the boundary between the Basin and Range to the east and the Walker Lane to the west. Along this boundary, strain is transferred from dextral shear in the Walker Lane to west-northwest directed extension in the Basin and Range. As such, the Astor Pass area lies in a transtensional setting consisting of both northwest-striking, left-stepping dextral faults and more northerly striking normal faults. The Astor Pass tufa tower implies the presence of a blind geothermal system. Previous studies suggest that deposition of the Astor Pass tufa was controlled by the intersection of a northwest-striking dextral normal fault and north-northwest striking normal fault. Subsequent drilling (to ~1200 m) has revealed fluid temperatures of ~94°C, confirming the presence of a blind geothermal system at Astor Pass. Expanding upon previous work and employing additional detailed geologic mapping, interpretation of 2D seismic reflection data and analysis of well cuttings, a 3-dimensional geologic model of the Astor Pass blind geothermal system was constructed. The 3D structural framework indicates that the Pleistocene tufa is associated with three discrete fault zones whose intersections plunge moderately to steeply NW-NNW. These critically stressed fault intersections act as conduits for upwelling geothermal fluids.

  13. 3D Reconstruction From Non-Euclidian Distance Fields Anders Sandholm Ken Museth

    E-print Network

    3D representation of the corresponding geometry by simple 1D interpolation between the 2D images for 3D recon- struction from binary images of contours that sparsely sample 3D geometry. Our approach-Euclidian images are then inter- polated to create a uniform volumetric implicit representation of the geometry

  14. Image Analysis for AutomaticImage Analysis for Automatic PhenotypingPhenotyping 3D Imaging3D Imaging

    E-print Network

    Glasbey, Chris

    Image Analysis for AutomaticImage Analysis for Automatic PhenotypingPhenotyping 3D Imaging3D to the red bottle · Need to recover the 3D geometry of the bottle for comparisons in size and shape Source: focus length from Wikipedia #12;High Resolution Colour Laser Scanner · A polychromatic RGB laser source

  15. Geometry of the Nojima fault at Nojima-Hirabayashi, Japan - II. Microstructures and their implications for permeability and strength

    USGS Publications Warehouse

    Moore, Diane E.; Lockner, D.A.; Ito, H.; Ikeda, R.; Tanaka, H.; Omura, K.

    2009-01-01

    Samples of damage-zone granodiorite and fault core from two drillholes into the active, strike-slip Nojima fault zone display microstructures and alteration features that explain their measured present-day strengths and permeabilities and provide insight on the evolution of these properties in the fault zone. The least deformed damage-zone rocks contain two sets of nearly perpendicular (60-90?? angles), roughly vertical fractures that are concentrated in quartz-rich areas, with one set typically dominating over the other. With increasing intensity of deformation, which corresponds generally to increasing proximity to the core, zones of heavily fragmented rock, termed microbreccia zones, develop between prominent fractures of both sets. Granodiorite adjoining intersecting microbreccia zones in the active fault strands has been repeatedly fractured and locally brecciated, accompanied by the generation of millimeter-scale voids that are partly filled with secondary minerals. Minor shear bands overprint some of the heavily deformed areas, and small-scale shear zones form from the pairing of closely spaced shear bands. Strength and permeability measurements were made on core collected from the fault within a year after a major (Kobe) earthquake. Measured strengths of the samples decrease regularly with increasing fracturing and fragmentation, such that the gouge of the fault core and completely brecciated samples from the damage zone are the weakest. Permeability increases with increasing disruption, generally reaching a peak in heavily fractured but still more or less cohesive rock at the scale of the laboratory samples. Complete loss of cohesion, as in the gouge or the interiors of large microbreccia zones, is accompanied by a reduction of permeability by 1-2 orders of magnitude below the peak values. The core samples show abundant evidence of hydrothermal alteration and mineral precipitation. Permeability is thus expected to decrease and strength to increase somewhat in active fault strands between earthquakes, as mineral deposits progressively seal fractures and fill pore spaces. ?? Birkh??user Verlag, Basel 2009.

  16. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  17. Holographic 3-D printer

    Microsoft Academic Search

    Masahiro Yamaguchi; Nagaaki Ohyama; Toshio Honda

    1990-01-01

    This paper proposes a holographic printer, which produces 3-D hard copies of computer processed objects. For the purpose of automatic making of 3-D hard copies of distortion free, a new method to synthesize holographic stereogram is proposed. It is is flat format and lippmann type holographic stereogram which can be printed by one optical step. The proposed hologram has not

  18. Regional fault pattern study - Sonam/Ajapa area offshore Western Niger Delta

    SciTech Connect

    Kanu, K.A.; Glass, J.E.; Okoro, P.C. [Chevron Nigeria Ltd., Lagos (Nigeria)] [and others

    1995-08-01

    A total of 900 km{sup 2} of high quality 3-D data was used to interpret structural trends: an inner trend containing the Mefa, Meji and Ajapa oil fields and a younger outer trend containing the large Sonam condensate field. Each trend is bounded by a large, regional down-to-the-coast fault system on the northeast and its associated counter-regional fault to the southwest. Hydrocarbon accumulations are contained within rollover anticlines adjacent to the main seaward-dipping fault trends. However, our data shows that structural geometries within each trend are highly three-dimensional. Anticlinal end closure is achieved by changes in fault detachment level and displacement which generally occur near major fault junctions. Thus, significant accumulations are associated with first-order high-relief accommodation zones. In the absence of such first-order closure, we cannot rely upon the systems of relatively small faults that occur on seaward dipping flanks and in areas of crestal collapse. Detailed 3-D mapping, supported by drilling results, shows that such faults do not link strongly together, thereby allowing leakage of hydrocarbons mound fault tips and up relay ramps between faults.

  19. Fault reactivation control on normal fault growth: an experimental study

    NASA Astrophysics Data System (ADS)

    Bellahsen, Nicolas; Daniel, Jean Marc

    2005-04-01

    Field studies frequently emphasize how fault reactivation is involved in the deformation of the upper crust. However, this phenomenon is generally neglected (except in inversion models) in analogue and numerical models performed to study fault network growth. Using sand/silicon analogue models, we show how pre-existing discontinuities can control the geometry and evolution of a younger fault network. The models show that the reactivation of pre-existing discontinuities and their orientation control: (i) the evolution of the main fault orientation distribution through time, (ii) the geometry of relay fault zones, (iii) the geometry of small scale faulting, and (iv) the geometry and location of fault-controlled basins and depocenters. These results are in good agreement with natural fault networks observed in both the Gulf of Suez and Lake Tanganyika. They demonstrate that heterogeneities such as pre-existing faults should be included in models designed to understand the behavior and the tectonic evolution of sedimentary basins.

  20. August 2003 3D Watermarking 3D WATERMARKING

    E-print Network

    Alatan, Aydin

    August 2003 3D Watermarking 3D WATERMARKING: Data Hiding on 3-D Triangle Meshes Mustafa Teke 2003 3D Watermarking Problem Definition Hiding information into 3D Objects with minimum distrotion rate, And make the watermark robust against attacks. #12;August 2003 3D Watermarking Intro The Method is Robust

  1. 3-D nFPGA: A Reconfigurable Architecture for 3-D CMOS\\/Nanomaterial Hybrid Digital Circuits

    Microsoft Academic Search

    Chen Dong; Deming Chen; Sansiri Haruehanroengra; Wei Wang

    2007-01-01

    In this paper, we introduce a novel reconfigurable architecture, named 3D field-programmable gate array (3D nFPGA), which utilizes 3D integration techniques and new nanoscale materials synergistically. The proposed architecture is based on CMOS nanohybrid techniques that incorporate nanomaterials such as carbon nanotube bundles and nanowire crossbars into CMOS fabrication process. This architecture also has built-in features for fault tolerance and

  2. Geometry of the Subducted Lithosphere Beneath the Banda Sea in Eastern Indonesia From Seismicity and Fault Plane Solutions

    Microsoft Academic Search

    Richard K. Cardwell; Bryan L. Isacks

    1978-01-01

    The spatial distribution of hypocenters in eastern Indonesia, together with 41 new and previously published fault plane solutions, can be explained by a simple model of two lithospheric plates descending into the upper mantle beneath the Banda Sea. The major one, defined by the shallow to deep hypocenters located along the Banda arc, is a laterally continuous slab that has

  3. Characteristic fault zone architectures as result of different failure modes: first results from scale models of normal faulting

    NASA Astrophysics Data System (ADS)

    Kettermann, Michael; Urai, Janos L.

    2014-05-01

    It is known that fault zone architecture and structural style vary distinctly between tensile and shear failure modes, with strong effects on the associated fluid flow properties. A systematically comparative study in 3D has not been done so far, though. Inferring transport properties in sub-seismic scale from fault network geometries would have important applications in brittle lithologies such as carbonates or basalts. We present a method to investigate the structural properties of fault networks in 3D using cohesive hemihydrate powder (CaSO4 * 1/2H2O) embedded in two layers of dry fine grained sand. The material properties of the sand and powder are well known from previous studies. By increasing the overburden stress the failure mode of the powder can be changed from tensile to shear failure. Using hemihydrate powder allows us to harden and excavate the layer after the deformation by wetting the model slowly and brushing off the overburden sand. Visual investigation of the 3D structures is then possible in very high resolution. Analyses using photographs and 3D models from photogrammetry include qualitative observations as well as measurements of e.g. strike of fault segments, fault dip or graben width. We show a total of eight experiments that produce graben faults at four different overburden stresses (0, 1.5, 3, 6 cm overburden thickness) and at two increasing stages of strain (3 and 5 mm). In this set of models we describe two structural domains that show characteristic differences in their defining attributes. The tensile domain at small overburden stress (0 and 1.5 cm overburden) shows strongly dilatant faults with open fissures, vertical faults and large changes in strike at segment boundaries. The shear domain, formed by larger overburden stress (6 cm overburden), shows shallower fault dips around 65° with striations, numerous undulating fault branches and splays with low-angle fault intersections. Models with 3 cm overburden show a hybrid failure type with features from both structural domains. Using these attributes could enhance the prediction of fault network structures in the subsurface with interest in fields like fractured reservoirs or ore mineralization. Validation of these results with seismic and outcrop data is primary goal of the consecutive work.

  4. The 3-D Universe

    NSDL National Science Digital Library

    This Moveable Museum article, available as a printable PDF file, looks at how astronomers use data to create 3-D models of the universe. Explore these concepts further using the recommended resources mentioned in this reading selection.

  5. 3D Plasmon Ruler

    SciTech Connect

    None

    2011-01-01

    In this animation of a 3D plasmon ruler, the plasmonic assembly acts as a transducer to deliver optical information about the structural dynamics of an attached protein. (courtesy of Paul Alivisatos group)

  6. TRACE 3-D documentation

    SciTech Connect

    Crandall, K.R.

    1987-08-01

    TRACE 3-D is an interactive beam-dynamics program that calculates the envelopes of a bunched beam, including linear space-charge forces, through a user-defined transport system. TRACE 3-D provides an immediate graphics display of the envelopes and the phase-space ellipses and allows nine types of beam-matching options. This report describes the beam-dynamics calculations and gives detailed instruction for using the code. Several examples are described in detail.

  7. Ricci flow for 3D shape analysis.

    PubMed

    Zeng, Wei; Samaras, Dimitris; Gu, Xianfeng David

    2010-04-01

    Ricci flow is a powerful curvature flow method, which is invariant to rigid motion, scaling, isometric, and conformal deformations. We present the first application of surface Ricci flow in computer vision. Previous methods based on conformal geometry, which only handle 3D shapes with simple topology, are subsumed by the Ricci flow-based method, which handles surfaces with arbitrary topology. We present a general framework for the computation of Ricci flow, which can design any Riemannian metric by user-defined curvature. The solution to Ricci flow is unique and robust to noise. We provide implementation details for Ricci flow on discrete surfaces of either euclidean or hyperbolic background geometry. Our Ricci flow-based method can convert all 3D problems into 2D domains and offers a general framework for 3D shape analysis. We demonstrate the applicability of this intrinsic shape representation through standard shape analysis problems, such as 3D shape matching and registration, and shape indexing. Surfaces with large nonrigid anisotropic deformations can be registered using Ricci flow with constraints of feature points and curves. We show how conformal equivalence can be used to index shapes in a 3D surface shape space with the use of Teichmüller space coordinates. Experimental results are shown on 3D face data sets with large expression deformations and on dynamic heart data. PMID:20224122

  8. Ricci Flow for 3D Shape Analysis

    Microsoft Academic Search

    Xianfeng Gu; Sen Wang; Junho Kim; Yun Zeng; Yang Wang; Hong Qin; Dimitris Samaras

    2007-01-01

    Ricci flow is a powerful curvature flow method in geo- metric analysis. This work is the first application of surface Ricci flow in computer vision. We show that previous meth- ods based on conformal geometries, such as harmonic maps and least-square conformal maps, which can only handle 3D shapes with simple topology are subsumed by our Ricci flowbasedmethodwhichcan handlesurfaceswitharbitrary topology.

  9. Structural evolution of the Currawong Pb-Zn-Cu deposit (Victoria, Australia) - new insights from 3D implicit modelling linked to structural observations

    NASA Astrophysics Data System (ADS)

    Vollgger, Stefan; Cruden, Alexander

    2015-04-01

    Structurally controlled mineralisation commonly shows distinctive geometries, orientations and spatial distributions that derive from associated structures. These structures have the ability to effectively transport, trap and focus fluids. Moreover, structures such as faults and shear zones can offset, truncate and spatially redistribute earlier mineralisation. We present a workflow that combines structural fieldwork with state-of-the-art 3D modelling to assess the structural framework of an ore deposit. Traditional 3D models of ore deposits rely on manual digitisation of cross sections and their subsequent linkage to form 3D objects. Consequently, the geological interpretation associated with each section will be reflected in the resulting 3D models. Such models are therefore biased and should be viewed and interpreted with caution. Conversely, 3D implicit modelling minimises the modelling bias by using an implicit function that is fitted to spatial data such as drillhole data. This function defines a scalar field, from which 3D isosurfaces can be extracted. Assay data can be visualised as 3D grade shells at various threshold grade values and used to analyse and measure the shape, distribution and orientation of mineralisation. Additionally, lithology codes from drillholes can be used to extract lithological boundaries in 3D without the need for manual digitisation. In our case study at the Palaeozoic Currawong Pb-Zn-Cu deposit (Victoria, Australia), orientations extracted from ore bodies within a 3D implicit model have been compared to structural field data collected around the deposit. The data and model suggest that Currawong's massive sulfide lenses have been structurally modified. Mineralisation trends are parallel to a dominant NW dipping foliation mapped in the field. This foliation overprints earlier bedding in the host metasediments that has been deformed into upright folds. Several sets of steep faults further increase the structural complexity of the deposit and offset mineralisation. Previously suggested conceptual models for Currawong do not adequately explain the spatial geometry and distribution of the mineralisation that is apparent in the 3D implicit model. We present a new structural history for the Currawong deposit, which explains the structural evolution (folding & faulting) of the massive sulfide lenses in 3D.

  10. 3D Model of the Neal Hot Springs Geothermal Area

    DOE Data Explorer

    Faulds, James E.

    The Neal Hot Springs geothermal system lies in a left-step in a north-striking, west-dipping normal fault system, consisting of the Neal Fault to the south and the Sugarloaf Butte Fault to the north (Edwards, 2013). The Neal Hot Springs 3D geologic model consists of 104 faults and 13 stratigraphic units. The stratigraphy is sub-horizontal to dipping <10 degrees and there is no predominant dip-direction. Geothermal production is exclusively from the Neal Fault south of, and within the step-over, while geothermal injection is into both the Neal Fault to the south of the step-over and faults within the step-over.

  11. 3D Model of the Neal Hot Springs Geothermal Area

    SciTech Connect

    Faulds, James E.

    2013-12-31

    The Neal Hot Springs geothermal system lies in a left-step in a north-striking, west-dipping normal fault system, consisting of the Neal Fault to the south and the Sugarloaf Butte Fault to the north (Edwards, 2013). The Neal Hot Springs 3D geologic model consists of 104 faults and 13 stratigraphic units. The stratigraphy is sub-horizontal to dipping <10 degrees and there is no predominant dip-direction. Geothermal production is exclusively from the Neal Fault south of, and within the step-over, while geothermal injection is into both the Neal Fault to the south of the step-over and faults within the step-over.

  12. FEM-based linear inverse modeling using a 3D source array to image magma chambers with free geometry. Application to InSAR data from Rabaul Caldera (PNG).

    NASA Astrophysics Data System (ADS)

    Ronchin, Erika; Masterlark, Timothy; Dawson, John; Saunders, Steve; Martí Molist, Joan

    2015-04-01

    In this study, we present a method to fully integrate a family of finite element models (FEMs) into the regularized linear inversion of InSAR data collected at Rabaul caldera (PNG) between February 2007 and December 2010. During this period the caldera experienced a long-term steady subsidence that characterized surface movement both inside the caldera and outside, on its western side. The inversion is based on an array of FEM sources in the sense that the Green's function matrix is a library of forward numerical displacement solutions generated by the sources of an array common to all FEMs. Each entry of the library is the LOS surface displacement generated by injecting a unity mass of fluid, of known density and bulk modulus, into a different source cavity of the array for each FEM. By using FEMs, we are taking advantage of their capability of including topography and heterogeneous distribution of elastic material properties. All FEMs of the family share the same mesh in which only one source is activated at the time by removing the corresponding elements and applying the unity fluid flux. The domain therefore only needs to be discretized once. This precludes remeshing for each activated source, thus reducing computational requirements, often a downside of FEM-based inversions. Without imposing an a-priori source, the method allows us to identify, from a least-squares standpoint, a complex distribution of fluid flux (or change in pressure) with a 3D free geometry within the source array, as dictated by the data. The results of applying the proposed inversion to Rabaul InSAR data show a shallow magmatic system under the caldera made of two interconnected lobes located at the two opposite sides of the caldera. These lobes could be consistent with feeding reservoirs of the ongoing Tavuvur volcano eruption of andesitic products, on the eastern side, and of the past Vulcan volcano eruptions of more evolved materials, on the western side. The interconnection and spatial distribution of sources find correspondence in the petrography of the volcanic products described in literature and in the dynamics of the single and twin eruptions that characterize the caldera. As many other volcanoes, Rabaul caldera is an active and dangerous volcanic system whose dynamics still need to be understood to effectively predict the behavior of future eruptions. The good results obtained from the application of the method to Rabaul caldera show that the proposed linear inversion based on the FEM array of sources is suitable to generate models of magmatic systems. The method can image in space and time the complex free geometry of the source that generates the deformation, widening our understanding of deformational sources and their dynamics. This takes source modeling a step towards more realistic source models.

  13. Magmatic Systems in 3-D

    NASA Astrophysics Data System (ADS)

    Kent, G. M.; Harding, A. J.; Babcock, J. M.; Orcutt, J. A.; Bazin, S.; Singh, S.; Detrick, R. S.; Canales, J. P.; Carbotte, S. M.; Diebold, J.

    2002-12-01

    Multichannel seismic (MCS) images of crustal magma chambers are ideal targets for advanced visualization techniques. In the mid-ocean ridge environment, reflections originating at the melt-lens are well separated from other reflection boundaries, such as the seafloor, layer 2A and Moho, which enables the effective use of transparency filters. 3-D visualization of seismic reflectivity falls into two broad categories: volume and surface rendering. Volumetric-based visualization is an extremely powerful approach for the rapid exploration of very dense 3-D datasets. These 3-D datasets are divided into volume elements or voxels, which are individually color coded depending on the assigned datum value; the user can define an opacity filter to reject plotting certain voxels. This transparency allows the user to peer into the data volume, enabling an easy identification of patterns or relationships that might have geologic merit. Multiple image volumes can be co-registered to look at correlations between two different data types (e.g., amplitude variation with offsets studies), in a manner analogous to draping attributes onto a surface. In contrast, surface visualization of seismic reflectivity usually involves producing "fence" diagrams of 2-D seismic profiles that are complemented with seafloor topography, along with point class data, draped lines and vectors (e.g. fault scarps, earthquake locations and plate-motions). The overlying seafloor can be made partially transparent or see-through, enabling 3-D correlations between seafloor structure and seismic reflectivity. Exploration of 3-D datasets requires additional thought when constructing and manipulating these complex objects. As numbers of visual objects grow in a particular scene, there is a tendency to mask overlapping objects; this clutter can be managed through the effective use of total or partial transparency (i.e., alpha-channel). In this way, the co-variation between different datasets can be investigated, even if one data object lies behind another. Stereoscopic viewing is another powerful tool to investigate 3-D relationships between objects. This form of immersion is constructed through viewing two separate images that are interleaved--typically 48 frames per second, per eye--and synced through an emitter and a set of specialized polarizing eyeglasses. The polarizing lenses flicker at an equivalent rate, blanking the eye for which a particular image was not drawn, producing the desired stereo effect. Volumetric visualization of the ARAD 3-D seismic dataset will be presented. The effective use of transparency reveals detailed structure of the melt-lens beneath the 9°03'N overlapping spreading center (OSC) along the East Pacific Rise, including melt-filled fractures within the propagating rift-tip. In addition, range-gated images of seismic reflectivity will be co-registered to investigate the physical properties (melt versus mush) of the magma chamber at this locale. Surface visualization of a dense, 2-D grid of MCS seismic data beneath Axial seamount (Juan de Fuca Ridge) will also be highlighted, including relationships between the summit caldera and rift zones, and the underlying (and humongous) magma chamber. A selection of Quicktime movies will be shown. Popcorn will be served, really!

  14. Dynamical system analysis and forecasting of deformation produced by an earthquake fault

    E-print Network

    Anghel, M; Rico-Martínez, R; Rico-Martinez, Ramiro

    2003-01-01

    We present a method of constructing low-dimensional nonlinear models describing the main dynamical features of a discrete 2D cellular fault zone, with many degrees of freedom, embedded in a 3D elastic solid. A given fault system is characterized by a set of parameters that describe the dynamics, rheology, property disorder, and fault geometry. Depending on the location in the system parameter space we show that the coarse dynamics of the fault can be confined to an attractor whose dimension is significantly smaller than the space in which the dynamics takes place. Our strategy of system reduction is to search for a few coherent structures that dominate the dynamics and to capture the interaction between these coherent structures. The identification of the basic interacting structures is obtained by applying the Proper Orthogonal Decomposition (POD) to the surface deformations fields that accompany strike-slip faulting accumulated over equal time intervals. We use a feed-forward artificial neural network (ANN)...

  15. Design of 3D-Printed Titanium Compliant Mechanisms

    NASA Technical Reports Server (NTRS)

    Merriam, Ezekiel G.; Jones, Jonathan E.; Howell, Larry L.

    2014-01-01

    This paper describes 3D-printed titanium compliant mechanisms for aerospace applications. It is meant as a primer to help engineers design compliant, multi-axis, printed parts that exhibit high performance. Topics covered include brief introductions to both compliant mechanism design and 3D printing in titanium, material and geometry considerations for 3D printing, modeling techniques, and case studies of both successful and unsuccessful part geometries. Key findings include recommended flexure geometries, minimum thicknesses, and general design guidelines for compliant printed parts that may not be obvious to the first time designer.

  16. INFILLING OF SPARSE 3D SEISMIC DATA FOR 3D FOCUSSING OPERATOR A. Gisolf * , M.J. van de Rijzen and D.J. Verschuur

    E-print Network

    -spread geometry used on land or for Ocean Bottom Cable acquisition, where shots are recorded in parallel receiverINFILLING OF SPARSE 3D SEISMIC DATA FOR 3D FOCUSSING OPERATOR ESTIMATION A. Gisolf * , M.J. van de

  17. Radiochromic 3D Detectors

    NASA Astrophysics Data System (ADS)

    Oldham, Mark

    2015-01-01

    Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle advantages of radiochromic dosimetry include greater tissue equivalence (radiologically) and the lack of requirement for development of the colour change. In a radiochromic material, the colour change arises direct from ionising interactions affecting dye molecules, without requiring any latent chemical, optical or thermal development, with important implications for increased accuracy and convenience. It is only relatively recently however, that 3D radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of 3D radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and 3D dose measurement in general.

  18. Lenticular Sheet 3-D Pictures And 3-D Projections

    NASA Astrophysics Data System (ADS)

    Marraud, A.; Bonnet, M.; Rambourg, A.

    1980-06-01

    The concept of lenticular sheet 3-D pictures dates from the beginning of this century. This method is responsible of commercial 3-D post-cards and 3-D photographic portraits. New applications are presented in this paper. They concern two domains where direct holographic 3-D reconstructions are impossible. These applications are the 3-D reconstruction of electron microscope pictures and the 3-D projection on a lenticular screen.

  19. First 3D Printout

    Microsoft Academic Search

    Sandeep Singh

    \\u000a I didn’t want to keep you waiting for too long, so in this chapter you’ll print your first 3D model using the Shapeways Creator\\u000a and Co-Creator. “What? I thought this book was about using SketchUp to develop models for 3D printing!” Well, you aren’t done\\u000a with SketchUp yet. You’ll be learning how to develop custom models using SketchUp starting in

  20. Quantum 3D Superstrings

    E-print Network

    Luca Mezincescu; Paul K. Townsend

    2011-10-21

    The classical Green-Schwarz superstring action, with N=1 or N=2 spacetime supersymmetry, exists for spacetime dimensions D=3,4,6,10, but quantization in the light-cone gauge breaks Lorentz invariance unless either D=10, which leads to critical superstring theory, or D=3. We give details of results presented previously for the bosonic and N=1 closed 3D (super)strings and extend them to the N=2 3D superstring. In all cases, the spectrum is parity-invariant and contains anyons of irrational spin.

  1. Urbanisation and 3d Spatial - a Geometric Approach

    NASA Astrophysics Data System (ADS)

    Duncan, E. E.; Rahman, A. Abdul

    2013-09-01

    Urbanisation creates immense competition for space, this may be attributed to an increase in population owing to domestic and external tourism. Most cities are constantly exploring all avenues in maximising its limited space. Hence, urban or city authorities need to plan, expand and use such three dimensional (3D) space above, on and below the city space. Thus, difficulties in property ownership and the geometric representation of the 3D city space is a major challenge. This research, investigates the concept of representing a geometric topological 3D spatial model capable of representing 3D volume parcels for man-made constructions above and below the 3D surface volume parcel. A review of spatial data models suggests that the 3D TIN (TEN) model is significant and can be used as a unified model. The concepts, logical and physical models of 3D TIN for 3D volumes using tetrahedrons as the base geometry is presented and implemented to show man-made constructions above and below the surface parcel within a user friendly graphical interface. Concepts for 3D topology and 3D analysis are discussed. Simulations of this model for 3D cadastre are implemented. This model can be adopted by most countries to enhance and streamline geometric 3D property ownership for urban centres. 3D TIN concept for spatial modelling can be adopted for the LA_Spatial part of the Land Administration Domain Model (LADM) (ISO/TC211, 2012), this satisfies the concept of 3D volumes.

  2. Influence of faults on groundwater flow and transport at YuccaMountain, Nevada

    SciTech Connect

    Cohen, Andrew J.B.; Sitar, Nicholas

    1999-10-07

    Numerical simulations of groundwater flow at Yucca Mountain, Nevada are used to investigate how faults influence groundwater flow pathways and regional-scale macrodispersion. The 3-D model has a unique grid block discretization that facilitates the accurate representation of the complex geologic structure present in faulted formations. Each hydrogeologic layer is discretized into a single layer of irregular and dipping grid blocks, and faults are discretized such that they are laterally continuous and varied in displacement varies along strike. In addition, the presence of altered fault zones is explicitly modeled, as appropriate. Simulations show that upward head gradients can be readily explained by the geometry of hydrogeologic layers, the variability of layer permeabilities, and the presence of permeable fault zones or faults with displacement only, not necessarily by upwelling from a deep aquifer. Large-scale macrodispersion results from the vertical and lateral diversion of flow near the contact of high- and low-permeability layers at faults, and from upward flow within high-permeability fault zones. Conversely, large-scale channeling can occur as a result of groundwater flow into areas with minimal fault displacement. Contaminants originating at the water table can flow in a direction significantly different from that of the water table gradient, and isolated zones of contaminants can occur at the water table downgradient. By conducting both 2-D and 3-D simulations, we show that the 2-D cross-sectional models traditionally used to examine flow in faulted formations may not be appropriate. In addition, the influence of a particular type of fault cannot be generalized; depending on the location where contaminants enter the saturated zone, faults may either enhance or inhibit vertical dispersion.

  3. 3D Printed Bionic Ears

    PubMed Central

    Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

    2013-01-01

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

  4. 3D printed bionic ears.

    PubMed

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

  5. 3D Computer Vision and Video Computing 3D Vision3D Vision

    E-print Network

    Zhu, Zhigang

    ;3 3D Computer Vision and Video Computing Problem StatementProblem Statement Two Subproblems1 3D Computer Vision and Video Computing 3D Vision3D Vision CSc I6716 Fall 2011 Topic 4 of Part II@cs.ccny.cuny.edu 3D Computer Vision and Video Computing Outline of MotionOutline of Motion Problems and Applications

  6. 3D Shape Match

    NSDL National Science Digital Library

    Dan Bunker

    2011-01-01

    This interactive Flash applet provides a Concentration-type game (called pelmanism in the UK) in which students must discern the properties of three-dimensional solids and their colors in order to match them in pairs. Spheres, cones, prisms and other standard 3-D shapes are hidden face down on cards. Time and number of trials needed to solve are recorded.

  7. 3D reservoir visualization

    SciTech Connect

    Van, B.T.; Pajon, J.L.; Joseph, P. (Inst. Francais du Petrole (FR))

    1991-11-01

    This paper shows how some simple 3D computer graphics tools can be combined to provide efficient software for visualizing and analyzing data obtained from reservoir simulators and geological simulations. The animation and interactive capabilities of the software quickly provide a deep understanding of the fluid-flow behavior and an accurate idea of the internal architecture of a reservoir.

  8. 3-D numerical modelling of the influence of reactivated pre-existing faults on the distribution of deformation: example of North-Western Ghana around 2.15-2.00 Ga

    NASA Astrophysics Data System (ADS)

    FENG, Xiaojun; Gerbault, Muriel; Martin, Roland; Ganne, Jérôme; Jessell, Mark

    2015-04-01

    High strain zones appear to play a significant role in feeding the upper crust with fluids and partially molten material from lower crust sources. The Bole-Bulenga terrain (North-Western Ghana) is located in between two subvertical shear zones, and mainly consists of high-grade orthogneisses, paragneisses and metabasites intruded by partially molten lower crustal material with monzogranites and orthogneisses (Eburnean orogeny, around 2.1 Ga). In order to understand the location of these high grade rocks at the edges and in between these two shear zones, a three dimensional numerical model was built to test the influence of different orientations of a system of branched strike-slip faults on visco-plastic deformation, under compressional and simple shear boundary conditions. Our models indicate domains of tensile vs. compressional strain as well as shear zones, and show that not only internal fault zones but also the host rock in between the faults behave relatively softer than external regions. Under both applied compressive and simple shear boundary conditions, these softened domains constitute preferential zones of tensile strain accommodation (dilation) in the upper crust, which may favor infilling by deeper partially molten rocks. Our modeled pre-existing faults zones are assumed to have formed during an early D1 stage of deformation, and they are shown to passively migrate and rotate together with the solid matrix under applied external boundary conditions (corresponding to a post D1 - early D2 phase of deformation). We suggest that in the Bole-Bulenga terrain, fluids or partially molten material stored in deeper crustal domains, preferentially intruded the upper crust within these highly (shear and tensile) strained domains, thanks to this D2 shearing deformation phase. Building relief at the surface is primarily controlled by fault orientations, together with mechanical parameters and external boundary conditions. In particular, greatest magnitudes of relief are obtained when faults dip in parallel one with the other and when they are inclined at depth, as they thus facilitate stress rotation and material transfer from depth. The host rock density does not play a primary role in producing relief compared to variations in friction angle at the crustal scale (30km thick). Relief increases by 200 - 300 m when the host rock density is increased by 200 kg/m3 , whereas relief drops by about 1200 m when decreasing the host rock friction from ? = 20° to 10°.

  9. Finite-Source Inversion for the 2004 Parkfield Earthquake using 3D Velocity Model Green's Functions

    Microsoft Academic Search

    A. Kim; D. Dreger; S. Larsen

    2008-01-01

    We determine finite fault models of the 2004 Parkfield earthquake using 3D Green's functions. Because of the dense station coverage and detailed 3D velocity structure model in this region, this earthquake provides an excellent opportunity to examine how the 3D velocity structure affects the finite fault inverse solutions. Various studies (e.g. Michaels and Eberhart-Phillips, 1991; Thurber et al., 2006) indicate

  10. Fault geometries illuminated from seismicity in central Taiwan: Implications for crustal scale structural boundaries in the northern Central Range

    Microsoft Academic Search

    Jonathan R. Gourley; Timothy Byrne; Yu-Chang Chan; Francis Wu; Ruey-Juin Rau

    2007-01-01

    Data sets of collapsed earthquake locations, earthquake focal mechanisms, GPS velocities and geologic data are integrated to constrain the geometry and kinematics of a crustal block within the accreted continental margin rocks of Taiwan's northeastern Central Range. This block is laterally extruding and exhuming towards the north-northeast. The block is bound on the west-southwest by the previously recognized Sanyi–Puli seismic

  11. Efficient Computation of Casimir Interactions between Arbitrary 3D Objects

    E-print Network

    White, Jacob K.

    We introduce an efficient technique for computing Casimir energies and forces between objects of arbitrarily complex 3D geometries. In contrast to other recently developed methods, our technique easily handles nonspheroidal, ...

  12. Thermochronometric Constraints on the Timing and Geometry of Extensional Faulting in the Whipple and Iron Mountains, Colorado River Extensional Corridor

    NASA Astrophysics Data System (ADS)

    Brichau, S.; Stockli, D. F.; Wells, M. L.; Dewane, T. J.; Schroeder, J.; Hager, C.

    2006-12-01

    The metamorphic core complexes in the Colorado River extensional corridor of the Basin and Range province represent some of the world`s premier examples of large-magnitude crustal extension and have inspired many of the modern concepts of metamorphic core complex formation. Tertiary exhumation of middle-crustal rocks in the Whipple Moutains core complex and its proposed breakway zone in the Iron Mountains present an ideal opportunity to better understand the timing, rates, and structural processes of footwall exhumation using low-T thermochronometry. For this study, detailed apatite and zircon (U-Th)/He data were collected along a swath parallel to the regional extensional direction from the Iron Moutains to the NE-most extent of the Whipple Moutains. The zircon (U-Th)/He ages (ZHe) range from ~14-47 Ma in the Whipple Mountains and from ~20-46 Ma in the Iron Mountains. The apatite (U-Th)/He ages (AHe) progress from ~14-27 Ma and from ~19-45 Ma in the Whipple and Iron Mountains, respectively. In the Whipple Moutains ZHe data exhibit a marked inflection point, constraining the onset of rapid exhumation at ~22 Ma. Both AHe and ZHe ages below the inflection point smoothly decrease in down-dip direction, yielding apparent time-integrated fault slip rates of 1.4 (+0.6/-0.3) km/Myr (ZHe) and 3.1 (+1.4/-0.7) km/Myr (AHe), respectively. A detailed look reveals that AHe and ZHe ages define structurally-repeated age-distance arrays best interpreted as progressive transfer of footwall slivers to the hanging wall during exhumation. The data illustrate the structural complexity of the Whipple detachment and the presence of footwall incisement slices. New AHe and ZHe ages from the Iron Moutains show that the timing of dominant exhumation (21-24 Ma) is similar to the onset of rapid exhumation of the Whipple detachment footwall. The Iron Mountains experienced early Miocene exhumation due to flexural rotation, resulting in westward tilting, likely recording the earliest history of extension and thus the onset of fault slip along the Whipple detachment fault system in its breakaway zone.

  13. Constitutive models of faults in the viscoelastic lithosphere

    NASA Astrophysics Data System (ADS)

    Moresi, Louis; Muhlhaus, Hans; Mansour, John; Miller, Meghan

    2013-04-01

    Moresi and Muhlhaus (2006) presented an algorithm for describing shear band formation and evolution as a coallescence of small, planar, fricition-failure surfaces. This algorithm assumed that sliding initially occurs at the angle to the maximum compressive stress dictated by Anderson faulting theory and demonstrated that shear bands form with the same angle as the microscopic angle of initial failure. Here we utilize the same microscopic model to generate frictional slip on prescribed surfaces which represent faults of arbitrary geometry in the viscoelastic lithosphere. The faults are actually represented by anisotropic weak zones of finite width, but they are instantiated from a 2D manifold represented by a cloud of points with associated normals and mechanical/history properties. Within the hybrid particle / finite-element code, Underworld, this approach gives a very flexible mechanism for describing complex 3D geometrical patterns of faults with no need to mirror this complexity in the thermal/mechanical solver. We explore a number of examples to demonstrate the strengths and weaknesses of this particular approach including a 3D model of the deformation of Southern California which accounts for the major fault systems. L. Moresi and H.-B. Mühlhaus, Anisotropic viscous models of large-deformation Mohr-Coulomb failure. Philosophical Magazine, 86:3287-3305, 2006.

  14. Creating Entirely Textured 3D Models of Real Objects Using Surface Flattening

    E-print Network

    Chetverikov, Dmitry

    ). Obtaining the 3D model of an object can be achieved by various 3D scanners, most frequently by laser are independent: precise geometry is provided by a 3D laser scanner, while textures are obtained from high qualityCreating Entirely Textured 3D Models of Real Objects Using Surface Flattening Zsolt Jank´o, G´eza K

  15. High-Frequency Radiation from an Earthquake Fault: A Review and a Hypothesis of Fractal Rupture Front Geometry

    NASA Astrophysics Data System (ADS)

    Gusev, A. A.

    2013-01-01

    Observed high-frequency (HF) radiation from earthquake faults exhibits specific properties that cannot be deduced or extrapolated from low-frequency fault behavior. In particular: (1) HF time functions look like random signals, with smooth mean spectrum and moderately heavy-tailed probability distribution function for amplitudes; (2) well-known directivity of low-frequency radiation related to rupture propagation is strongly reduced at HF, suggesting incoherent (delta-correlated) behavior of the HF radiator, and contradicting the usual picture of a rupture front as a regular, non-fractal moving line; (3) in the spectral domain, HF radiation occupies a certain specific band seen as a plateau on acceleration source spectra K(f) = f2 dot{M}0 (f) . The lower cutoff frequency f b of K(f) spectra is often located significantly higher than the common spectral corner frequency f c, or f a. In many cases, empirical f b( M 0) trends are significantly slower as compared to the simple f b ? M {0/-1/3}, testifying the lack of similarity in spectral shapes; (4) evidence is accumulating in support of the reality of the upper cutoff frequency of K(f): fault-controlled f max, or f uf. However, its identification is often hampered by such problems as: (a) strong interference between f uf and site-controlled f max; (b) possible location of f uf above the observable spectral range; and (c) substantial deviations of individual source spectra from the ideal spectral shape; (5) intrinsic structure of random-like HF radiation has been shown to bear significant self-similar (fractal) features. A HF signal can be represented as a product of a random HF "carrier signal" with constant mean square amplitude, and a positive modulation function, again random, that represents a signal envelope. It is this modulation function that shows approximately fractal behavior. This kind of behavior was revealed over a broad range of time scales, from 1 to 300 s from teleseismic data and from 0.04 to 30 s from near-fault accelerogram data. To explain in a qualitative way many of these features, it is proposed that rupture propagation can be visualized as occurring, simultaneously, at two different space-time scales. At a macro-scale (i.e. at a low resolution view), one can safely believe in the reality of a singly connected rupture with a front as a smooth line, like a crack tip, that propagates in a locally unilateral way. At a micro-scale, the rupture front is tortuous and disjoint, and can be visualized as a multiply connected fractal "line" or polyline. It propagates, locally, in random directions, and is governed by stochastic regularities, including fractal time structure. The two scales and styles are separated by a certain characteristic time, of the order of (0.07-0.15) × rupture duration. The domain of fractal behavior spans a certain HF frequency range; its boundaries, related to the lower and upper fractal limits, are believed to be manifested as f b and f uf.

  16. Context-driven automated target detection in 3D data

    Microsoft Academic Search

    Karen F. West; Brian N. Webb; James R. Lersch; Steven Pothier; Joseph M. Triscari; A. E. Iverson

    2004-01-01

    This paper summarizes a system, and its component algorithms, for context-driven target vehicle detection in 3-D data that was developed under the Defense Advanced Research Projects Agency (DARPA) Exploitation of 3-D Data (E3D) Program. In order to determine the power of shape and geometry for the extraction of context objects and the detection of targets, our algorithm research and development

  17. Stereo Vision Geometry Optimal Correction of Correspondence

    E-print Network

    Dorst, Leo

    Stereo Vision Geometry Optimal Correction of Correspondence 3-D Reconstruction of Points and Lines: 3-D Computation by Stereo Vision Kanatani Reading Club July 24 2009 Kanatani Reading Club Chapter 6: 3-D Computation by Stereo Vision #12;Stereo Vision Geometry Optimal Correction of Correspondence 3-D

  18. 3d X 3d X SrTiO3Ti 2p 3d

    E-print Network

    Katsumoto, Shingo

    XX 3d X 3d X X XX X XX SrTiO3Ti 2p 3d SrTiO3Ti 2p 3d 2p 2p SrTiO3 ts) 2p3/2 (t2g) 2p3/2 (e ) 2p1/2 (eg)2p SrTiO3 3d unit (t2g) (eg) (eg)2p1/2 (t2g)3d (Ti Fe Cu) arb. ( 2g) (Ti, Fe, Cu) y(ansitynten 3d In 3d 468464460456 · Photon Energy (e

  19. Migrating from 2D to 3D in "Autograph"

    ERIC Educational Resources Information Center

    Butler, Douglas

    2006-01-01

    With both "Cabri" and "Autograph" now venturing into 3D, the dimension that previously was only demonstrated in the classroom with a lot of arm waving and crude wire cages can now be explored dynamically on screen. "Cabri 3D" concentrates on constructions, using the principles of Euclidian geometry, whereas "Autograph" creates objects using a…

  20. 3D gradient coil design for open MRI systems

    Microsoft Academic Search

    Peter T. While; Larry K. Forbes; Stuart Crozier

    2010-01-01

    Existing gradient coil design methods typically require some predetermined surface to be specified upon which the precise locations of coil windings are optimised with respect to gradient homogeneity and other measures of coil performance. In contrast, in this paper an analytic inverse method is presented for the theoretical design of 3D gradient coils in which the precise 3D geometry of

  1. 3-D Gradient Coil Design—Initial Theoretical Framework

    Microsoft Academic Search

    Peter T. While; Larry K. Forbes; Stuart Crozier

    2009-01-01

    An analytic inverse method is presented for the theoretical design of 3-D transverse gradient coils. Existing gradient coil design methods require the basic geometry of the coil to be predetermined before optimization. Typically, coil windings are constrained to lie on cylindrical, planar, spherical, or conical surfaces. In this paper, a fully 3-D region in the solution space is explored and

  2. Layout-based 3D solid modeling for IC

    Microsoft Academic Search

    Zhiping Yu; K. Wang; Tao Chen; R. W. Dutton; J. T. Watt

    1995-01-01

    A software system for 3D solid modeling of IC structures (devices, interconnection, and circuits) based on the layout design and processing information is described. Both the 3D perspective view and 2D cross sections of the structure can be examined using the system. Features of the system include automatic update of the geometry as the layout is changed and dynamic display

  3. Advanced geometric techniques in 3D process simulation

    Microsoft Academic Search

    N. A. Golias; R. W. Dutton

    1996-01-01

    The modeling of semiconductor devices in the deep submicron era is a complicated and challenging procedure. Due to continuous scaling of IC structures many physical effects pose requirements for a full 3D simulation. The incorporation of advanced computational geometry techniques is imperative in the realization of such 3D process simulation tools. The simulation of a virtual factory, with the various

  4. 3-D Grab!

    NASA Astrophysics Data System (ADS)

    Connors, M. G.; Schofield, I. S.

    2012-12-01

    Modern technologies in imaging greatly extend the potential to present visual information. With recently developed software tools, the perception of the third dimension can not only dramatically enhance presentation, but also allow spatial data to be better encoded. 3-D images can be taken for many subjects with only one camera, carefully moved to generate a stereo pair. Color anaglyph viewing now can be very effective using computer screens, and active filter technologies can enhance visual effects with ever-decreasing cost. We will present various novel results of 3-D imaging, including those from the auroral observations of the new twinned Athabasca University Geophysical Observatories.; Single camera stereo image for viewing with red/cyan glasses.

  5. Interactives: 3D Shapes

    NSDL National Science Digital Library

    How much liquid can that glass hold? What are the dimensions of that package that's heading off to a friend overseas? Answers to both of those questions (and many more) can be found in this lovely interactive feature on 3D shapes created by experts at the Annenberg Media group. Visitors to this site will learn about three-dimensional geometric shapes by examining a number of objects through a number of interactive exercises and games. The materials are divided into four sections, which include "3D Shapes", "Surface Area & Volume", and "Platonic Solids". The "Platonic Solids" area is quite a bit of fun, as visitors will get the opportunity to print out foldable shapes such as a tetrahedron. A short fifteen question quiz that tests the materials covered by these various activities rounds out the site.

  6. Sketching 3D Animations

    Microsoft Academic Search

    Jean-francis Balaguer; Enrico Gobbetti

    1995-01-01

    We are interested in providing animators with a general-purpose tool allowing them to create animations using straight-ahead actions as well as pose-to-pose techniques. Our approach seeks to bring the expressiveness of real-time motion capture systems into a general-purpose multi-track system running on a graphics workstation. We emphasize the use of high-bandwidth interaction with 3D objects together with specific data reduction

  7. 3D Flyover Movies

    NSDL National Science Digital Library

    Marvin Simkin

    2005-01-01

    This collection of 3D flyover movies depicts geologically interesting localities in the Southwest United States. The selection includes well-known landmarks such as Meteor Crater, Monument Valley, Hopi Buttes, and others. They are available in a number of different formats and file sizes. The movies, the data files used to make them, and the software to view them are all available for free download. There is also a link to a tutorial on how to make Fledermaus scenes and movies.

  8. Genesis and growth of the NW trending normal fault array of the Levant Basin

    NASA Astrophysics Data System (ADS)

    Ghalayini, Ramadan; Homberg, Catherine; Daniel, Jean-Marc; Nader, Fadi

    2015-04-01

    The Levant basin, located in the Eastern Mediterranean region, presents a conspicuous normal fault array in the interpreted Oligo-Miocene units. How did the faults grow, evolve and interact with each other is important in order to increase our understanding on the growth of normal fault systems in general and the structural setting of the Levant Basin in particular. Found offshore Lebanon, and partly offshore SE Cyprus and Israel, these faults are layer bound and comprised only in the Oligo-Miocene units, bounded by the base Messinian horizon and Eocene unconformity horizon at their top and bottom respectively. They correlate well with the thickness of the Oligo-Miocene sediments which might explain their distribution. Quantitative and qualitative fault analysis techniques were applied to a 3D seismic reflection dataset. Deduced thickness variations at the Miocene interval (across the faults) and growth index calculations show that the motion of these faults is syn-sedimentary since the Early Miocene time. As observed in cross-section; most of the faults are throughgoing faults and do not show significant refraction or bifurcation. However, the displacement data show that the fault history is complex and imply that the Cenozoic package is characterized by a significant mechanical layering. The latter has influenced the fault development with preferential and double nucleation sites of fault segments which later linked by vertical tip propagation. An asymmetry in the upward and downward vertical restriction is also deduced and horizontal linkages also occurred. The various geometric observations and displacement distribution indicate a strong resemblance between the normal faults of the Levant Basin and the widely documented polygonal fault systems. As polygonal faults are characterized by polygonal planform geometry and the faults in the Levant Basin are linear, we attribute the difference in their planform geometry to a regional anisotropic NW-SE stress field dominant since Oligocene times. These faults are thus possibly formed in relation with the vertical contraction of the fine-grained host rock unit with the conjunction of a complex fluid pressure profile in the sedimentary pile. Our interpretation suggested that growth of contractional faults on a basin-scale generally follows the isolated model, at least in their early history, accumulating length proportionally with displacement. When subject to an anisotropic regional stress field, they will grow very similarly to normal tectonic faults, being then influenced by mutual interaction and mechanical layering.

  9. Spring 2010 3D Photography

    E-print Network

    Stamos, Ioannis

    Spring 2010 3D Photography -------------------------------------------------------------- Project I a specified viewpoint. This range image is expressed as a two-dimensional array of 3-D points. 3-D points that are neighbors in this array are probably neighbors in the actual 3-D surface, unless the points lie on a shape

  10. HYFRACP3D. Finite Element Code for 3D-Hydraulic Fracture Propagation Equations (3-layer)

    Microsoft Academic Search

    S. H. Advani; J. K. Lee; H. Khattab

    1985-01-01

    HYFRACP3D is a finite element program for simulation of a pseudo three-dimensional fracture geometries with a two-dimensional planar solution. The model predicts the height, width and winglength over time for a hydraulic fracture propagating in a three-layered system of rocks with variable rock mechanics properties.

  11. HYFRACP3D. Finite Element Code For 3D-Hydraulic Fracture Propagation Equations (3-layer)

    Microsoft Academic Search

    S. H. Advani; J. K. Lee; H. Khattab

    1985-01-01

    HYFRACP3D is a finite element program for simulation of a pseudo three-dimensional fracture geometries with a two-dimensional planar solution. The model predicts the height, width and winglength over time for a hydraulic fracture propagating in a three-layered system of rocks with variable rock mechanics properties.

  12. Ductile Faults Control Seismogenic Movement on Oceanic Transforms

    NASA Astrophysics Data System (ADS)

    Lister, G. S.; Tkalcic, H.; Forster, M. A.; McClusky, S.

    2014-12-01

    Structural Geology is about 3D geometry and the symphony of kinematically-coordinated movement. In this case we discuss patterns of violent relative displacement inferred from focal plane data for earthquakes. Systematic stereographic analysis of centroid moment tensor data often shows well-defined orientation groups in scatterplots of fault plane normals and associated slip line vectors. These allow important geodynamic inferences, e.g., we can show that ductile faults control the geometry of oceanic transforms, and that normal fault earthquakes on spreading ridges are usually skewed with respect to adjacent transform faults. To explain this asymmetry requires finite rock strength, but it also means that it is not brittle failure that controls the orientation of oceanic transforms. This asymmetry also requires formation of tilt block geometries reminiscent of Basin-and-Range-style continental extension, systematic offset of earthquake hypocentres from the spreading ridge, and a general complexity in magma-fault interactions that is far beyond what might be expected if ocean-floor spreading is the result of dilating tension-mode fractures in dyke swarms. The role of ductile faulting should be given special mention because mostly it is argued that brittle faults are responsible for earthquakes. Yet many other examples of ductile faults in operation can be inferred, e.g., ductile faults associated with slab drop-off, where slab boudinage leads to extensional ductile faults and seismic activity driven by the pulling away of a relict slab, e.g., beneath the Hindu Kush. Another example might be found by close examination of the tectonic significance of the lowermost of the double (or paired) seismic zones such as can be seen in cross-sections of the subducting slab beneath Japan. The lowermost of the paired seismic zones may mark the locus of aseismic ductile shears or detachments formed by slumping of gigantic sheets of rock attempting to slide down the face of actively subducting slabs. Seismogenic activity may be driven by ductile faulting (again related to boudinage) of the relatively strong sheet of the subducting slab overlying this movement zone. The role of ductile faulting has been undervalued in earthquake generation, and this data suggests revision of seismotectonic doctrines may be necessary.

  13. 3D Computer Vision and Video Computing 3D Vision3D Vision

    E-print Network

    Zhu, Zhigang

    1 3D Computer Vision and Video Computing 3D Vision3D Vision CSc I6716 Fall 2010 Topic 4 of Part II@cs.ccny.cuny.edu 3D Computer Vision and Video Computing Outline of MotionOutline of Motion Problems and Applications The importance of visual motion Problem Statement The Motion Field of Rigid Motion Basics ­ Notations

  14. Simulating intense shock pulses due to asperities during fault-slip

    NASA Astrophysics Data System (ADS)

    Sainoki, Atsushi; Mitri, Hani S.

    2014-04-01

    Seismic waves arising from fault-slip that occurs in underground mines could inflict severe damage to mine openings. Experimental results have revealed that intense shock pulses could generate due to the unloading of fault surface asperities that move apart during the fault-slip. This study focuses on examining the effect of fault surface asperities on the seismic waves arising from fault-slip. By means of a mine-wide model, dynamic analyses are carried out in order to simulate collision and unloading of fault surface asperities. Saeb and Amadei's model and Barton's shear strength model are newly implemented into constitutive models of FLAC3D code for the analyses. Parametrical study is conducted with the dynamic analyses in order to examine the most influential factor on the generation of intense seismic waves. The results reveal that stress release due to the unloading of the asperities has a significant influence on the intensity of seismic waves, while the collision of asperities, stiffness of the fault, and asperity geometry have a much lesser influence. When the stress release is large, the peak particle velocity excited by seismic waves is found to increase threefold, compared to that for fault-slip occurring along a planar surface. It indicates that significant deterioration of rockmasses could be induced due to the high particle velocities. This study has numerically confirmed the hypothesis that intense shock pulses could occur due to the unloading of fault surface asperities.

  15. Three-Dimensional (3D) Structure of the Malawi Rift from Remote Sensing and Geophysics Data

    NASA Astrophysics Data System (ADS)

    Salmi, Haifa S. Al; Abdelsalam, Mohamed G.

    2014-05-01

    The Malawi rift is a Cenozoic aged rift representing the southernmost segment of the Western Branch of the East African Rift System (EARS). This rift extends over 900 km from the Rungwe volcanic province (Tanzania) in the north to the Urema graben (Mozambique) to the south, with an average width of 50km. It traverses a complex array of Proterozoic orogenic belts of different ages and Permo-Triassic (Karoo) and cretaceous graben systems. The rift's depth is between 3 to 5km partitioned between the topographic escarpment and the sediments fill. The basin's subsidence reflects accumulation of sediments and rift flank uplift. Regardless of its importance in understanding rift tectonics, especially in Africa, the three-dimensional (3D) geometry of the rift is not fully understood. This research presents results from detailed analysis of Digital Elevation Model (DEM) extracted from the Shuttle Radar Topography Mission (SRTM) data to map surface morphological expressions of the entire basin. These results are compared with available seismic data to provide along-strike and at depth variation of the geometry of the border fault systems, nature of rift segmentation and alternation of the polarity of half-grabens, and the partitioning of displacement between exposed and sub-surface border faults. Our results show the following: (1) Surface expression of border faults show that, unlike the typical half-graben en-echelon rift model, where half-graben segments with opposite polarity are linked together through accommodation zones indicative of soft linkage, the Malawi rift shows along-strike segmentation by changing geometry from half-graben to full graben geometry. A half-graben with specific polarity passes through a full-graben geometry before giving place to a half-graben with the opposite polarity. The length of half-gaben and graben segments becomes shorter as the rift progresses from north to south, and this is accompanied by a decrease in displacement within border faults. This geometry is indicative of the propagation of border faults through hard linkage. (2) The continuation of border faults at the subsurface show patterns consistent with those observed at the surface. At the sub-surface, the general trend of rift segmentation, formation of full grabens at the end of each segment, and the decreases in the length of the segments from north to south is consistent with observations at the surface. This suggests the homogeneity of strain accommodation throughout the depth of border faults. (3) Zones of segmentation of the Malawi rift coincide with regions where the pre-existing structures (both the Proterozoic basement and the Karoo grabens) are at high angle to the trend of the rift whereas well-developed border faults of the basin coincides with N-trending pre-existing structures sub-parallel to the rift.

  16. 3D Audio System

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Ames Research Center research into virtual reality led to the development of the Convolvotron, a high speed digital audio processing system that delivers three-dimensional sound over headphones. It consists of a two-card set designed for use with a personal computer. The Convolvotron's primary application is presentation of 3D audio signals over headphones. Four independent sound sources are filtered with large time-varying filters that compensate for motion. The perceived location of the sound remains constant. Possible applications are in air traffic control towers or airplane cockpits, hearing and perception research and virtual reality development.

  17. Revealing a Fault Plane with Hypocenters

    NSDL National Science Digital Library

    In this exercise, learners will plot earthquake hypocenters along a cross-section in an attempt to 'image' a fault deep beneath the surface. The hypocenter data is from the aftershock sequence of the 1986 North Palm Springs, CA earthquake. This activity is suitable for learners who have a good understanding of high school algebra and geometry. This activity can be typically accomplished during a 50-minute science class unit on Earth science. The exercise itself is performed off-line, although a 3-D model of the results can be viewed online. This activity supports the Reasoning and Proof and Geometry Standards (grades 9-12) of the Principles and Standards for School Mathematics (Source: National Council of Teachers of Mathematics -NCTM).

  18. Estimation of Precambrian basement topography in Central and Southeastern Wisconsin from 3D modeling of gravity and aeromagnetic data

    NASA Astrophysics Data System (ADS)

    Skalbeck, John D.; Koski, Adrian J.; Peterson, Matthew T.

    2014-07-01

    Increased concerns about groundwater resources in Wisconsin have brought about the need for better understanding of the subsurface geologic structure that leads to developing conceptual hydrogeologic models for numerical simulation of groundwater flow. Models are often based on sparse data from well logs usually located large distances apart and limited in depth. Model assumptions based on limited spatial data typically require simplification that may add uncertainty to the simulation results and the accuracy of a groundwater model. Three dimensional (3D) modeling of gravity and aeromagnetic data provides another tool for the groundwater modeler to better constrain the conceptual model of a hydrogeologic system. The area near the Waukesha Fault in southeastern Wisconsin provides an excellent research opportunity for our proposed approach because of the strong gravity and aeromagnetic anomalies associated with the fault, the apparent complexity in fault geometry, and uncertainty in Precambrian basement depth and structure. Fond du Lac County provides another opportunity to apply this approach because the Precambrian basement topography throughout the area is known to be very undulated and this uneven basement surface controls water well yields and creates zones of stagnant water. The results of the 3D modeling of gravity and aeromagnetic data provide a detailed estimation of the Precambrian basement topography in Fond Du Lac County and southeastern Wisconsin that may be useful in determining ground water flow and quality in this region.

  19. Four-dimensional evolution of a salt-related fault network: Eugene Island Block 330 field, offshore Louisiana

    SciTech Connect

    Rowan, M.G. [Univ. of Colorado, Boulder, CO (United States); Hart, B.S. [New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States); Nelson, S.; Flemings, P.B. [Pennsylvania State Univ., University Park, PA (United States)

    1996-12-31

    The Eugene Island Block 330 field consists of two anticlinal rollovers in the hanging wall of a listric normal fault system that detaches along a deep salt weld. We use interpretation of well and 3D seismic data, 3D structural restoration, and fault analysis techniques to investigate the evolution of the three-dimensional geometry through time and its impact on hydrocarbon migration and entrapment. The master fault that currently forms the northeastern boundary of the field originated as two distinct, overlapping fault segments separated by a relay ramp. The segments linked by breaching of the ramp prior to 2.2 Ma. The resultant footwall splay continued to accommodate a significant proportion of the net slip, but became essentially inactive by 1.5 Ma. In the hanging wall of the master fault, interaction between two synthetic splays and an antithetic fault resulted in a similar, complex history of varying displacement distribution. Analysis of evolving hanging and footwall cutoff geometries on the various faults suggests that cross-fault hydrocarbon migration at sand-on-sand contacts may have contributed to reservoir filling. This scenario requires that Lentic (>2.2 Ma) sands in the footwall were connected to deeper hydrocarbon sources, which cannot be demonstrated and may be problematic because of the discontinuous nature of these sands. Moreover, the present distribution of hydrocarbons and the sealing nature of faults at some sand-on-sand contacts imply that another mechanism, such as episodic vertical migration along fault zone is required to introduce hydrocarbons into the shallow reservoirs.

  20. Four-dimensional evolution of a salt-related fault network: Eugene Island Block 330 field, offshore Louisiana

    SciTech Connect

    Rowan, M.G. (Univ. of Colorado, Boulder, CO (United States)); Hart, B.S. (New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States)); Nelson, S.; Flemings, P.B. (Pennsylvania State Univ., University Park, PA (United States))

    1996-01-01

    The Eugene Island Block 330 field consists of two anticlinal rollovers in the hanging wall of a listric normal fault system that detaches along a deep salt weld. We use interpretation of well and 3D seismic data, 3D structural restoration, and fault analysis techniques to investigate the evolution of the three-dimensional geometry through time and its impact on hydrocarbon migration and entrapment. The master fault that currently forms the northeastern boundary of the field originated as two distinct, overlapping fault segments separated by a relay ramp. The segments linked by breaching of the ramp prior to 2.2 Ma. The resultant footwall splay continued to accommodate a significant proportion of the net slip, but became essentially inactive by 1.5 Ma. In the hanging wall of the master fault, interaction between two synthetic splays and an antithetic fault resulted in a similar, complex history of varying displacement distribution. Analysis of evolving hanging and footwall cutoff geometries on the various faults suggests that cross-fault hydrocarbon migration at sand-on-sand contacts may have contributed to reservoir filling. This scenario requires that Lentic (>2.2 Ma) sands in the footwall were connected to deeper hydrocarbon sources, which cannot be demonstrated and may be problematic because of the discontinuous nature of these sands. Moreover, the present distribution of hydrocarbons and the sealing nature of faults at some sand-on-sand contacts imply that another mechanism, such as episodic vertical migration along fault zone is required to introduce hydrocarbons into the shallow reservoirs.

  1. Modeling of Mantle Convection in 3D Subduction Zones

    NASA Astrophysics Data System (ADS)

    Bengtson, A. K.; van Keken, P. E.; Lin, S.; Kneller, E. A.

    2010-12-01

    The influence of 3D subduction zone geometries on mantle convection patterns is not well characterized. Subducting plates with complex 3D geometries often exhibit seismological signatures that cannot be explained by 2D flow patterns [Hoernle et al. Nature 2008/2009; Long and Silver Science 2008; Kneller et al. Nature 2007]. We use finite element methods to study the lateral transport and thermal structure in 3D subduction zones and their evolution over time. Realistic 3D geometries were created from seismological observations for both the Marianas and Central America, building upon the work of Kneller et al. [Nature 2007; Geochem. Geophys. Geosyst. 2008]. Highly refined meshes were created using spherical geometry on a Cartesian mesh, and slab motion was prescribed in a kinematic manner. The finite element code Sepran was used to solve the Stokes and heat equations using diffusion creep laws for viscosity. We present the velocities, temperatures, and pressures in the mantle wedge for the Marianas and Central America regions. Comparisons are made between 2D and 3D flow patterns to test the dependence of flow on 3D geometries, in addition to dependence of flow on plate direction. Resulting thermal and lateral structures are important for understanding mantle and slab mineralogy and seismic signatures. We find the lateral transport is particularly important in regions of strong obliquity and trench curvature.

  2. Simulating Large-Scale Earthquake Dynamic Rupture Scenarios On Natural Fault Zones Using the ADER-DG Method

    NASA Astrophysics Data System (ADS)

    Gabriel, Alice; Pelties, Christian

    2014-05-01

    In this presentation we will demonstrate the benefits of using modern numerical methods to support physic-based ground motion modeling and research. For this purpose, we utilize SeisSol an arbitrary high-order derivative Discontinuous Galerkin (ADER-DG) scheme to solve the spontaneous rupture problem with high-order accuracy in space and time using three-dimensional unstructured tetrahedral meshes. We recently verified the method in various advanced test cases of the 'SCEC/USGS Dynamic Earthquake Rupture Code Verification Exercise' benchmark suite, including branching and dipping fault systems, heterogeneous background stresses, bi-material faults and rate-and-state friction constitutive formulations. Now, we study the dynamic rupture process using 3D meshes of fault systems constructed from geological and geophysical constraints, such as high-resolution topography, 3D velocity models and fault geometries. Our starting point is a large scale earthquake dynamic rupture scenario based on the 1994 Northridge blind thrust event in Southern California. Starting from this well documented and extensively studied event, we intend to understand the ground-motion, including the relevant high frequency content, generated from complex fault systems and its variation arising from various physical constraints. For example, our results imply that the Northridge fault geometry favors a pulse-like rupture behavior.

  3. E3D. 3D Elastic Seismic Wave Propagation Code

    SciTech Connect

    Larsen, S.; Harris, D.; Schultz, C.; Maddix, D.; Bakowsky, T.; Bent, L. [Lawrence Livermore National Lab., CA (United States)

    1998-01-01

    E3D is capable of simulating seismic wave propagation in a 3D heterogeneous earth. Seismic waves are initiated by earthquake, explosive, and/or other sources. These waves propagate through a 3D geologic model, and are simulated as synthetic seismograms or other graphical output.

  4. E3D. 3D Elastic Seismic Wave Propagation Code

    Microsoft Academic Search

    S. Larsen; D. Harris; C. Schultz; D. Maddix; T. Bakowsky; L. Bent

    1998-01-01

    E3D is capable of simulating seismic wave propagation in a 3D heterogeneous earth. Seismic waves are initiated by earthquake, explosive, and\\/or other sources. These waves propagate through a 3D geologic model, and are simulated as synthetic seismograms or other graphical output.

  5. Trishear for curved faults

    NASA Astrophysics Data System (ADS)

    Brandenburg, J. P.

    2013-08-01

    Fault-propagation folds form an important trapping element in both onshore and offshore fold-thrust belts, and as such benefit from reliable interpretation. Building an accurate geologic interpretation of such structures requires palinspastic restorations, which are made more challenging by the interplay between folding and faulting. Trishear (Erslev, 1991; Allmendinger, 1998) is a useful tool to unravel this relationship kinematically, but is limited by a restriction to planar fault geometries, or at least planar fault segments. Here, new methods are presented for trishear along continuously curved reverse faults defining a flat-ramp transition. In these methods, rotation of the hanging wall above a curved fault is coupled to translation along a horizontal detachment. Including hanging wall rotation allows for investigation of structures with progressive backlimb rotation. Application of the new algorithms are shown for two fault-propagation fold structures: the Turner Valley Anticline in Southwestern Alberta, and the Alpha Structure in the Niger Delta.

  6. Distributed deformation and block rotation in 3D

    NASA Technical Reports Server (NTRS)

    Scotti, Oona; Nur, Amos; Estevez, Raul

    1990-01-01

    The authors address how block rotation and complex distributed deformation in the Earth's shallow crust may be explained within a stationary regional stress field. Distributed deformation is characterized by domains of sub-parallel fault-bounded blocks. In response to the contemporaneous activity of neighboring domains some domains rotate, as suggested by both structural and paleomagnetic evidence. Rotations within domains are achieved through the contemporaneous slip and rotation of the faults and of the blocks they bound. Thus, in regions of distributed deformation, faults must remain active in spite of their poor orientation in the stress field. The authors developed a model that tracks the orientation of blocks and their bounding faults during rotation in a 3D stress field. In the model, the effective stress magnitudes of the principal stresses (sigma sub 1, sigma sub 2, and sigma sub 3) are controlled by the orientation of fault sets in each domain. Therefore, adjacent fault sets with differing orientations may be active and may display differing faulting styles, and a given set of faults may change its style of motion as it rotates within a stationary stress regime. The style of faulting predicted by the model depends on a dimensionless parameter phi = (sigma sub 2 - sigma sub 3)/(sigma sub 1 - sigma sub 3). Thus, the authors present a model for complex distributed deformation and complex offset history requiring neither geographical nor temporal changes in the stress regime. They apply the model to the Western Transverse Range domain of southern California. There, it is mechanically feasible for blocks and faults to have experienced up to 75 degrees of clockwise rotation in a phi = 0.1 strike-slip stress regime. The results of the model suggest that this domain may first have accommodated deformation along preexisting NNE-SSW faults, reactivated as normal faults. After rotation, these same faults became strike-slip in nature.

  7. 3D collar design creation

    Microsoft Academic Search

    Jing-Jing Fang

    2003-01-01

    This preliminary research revolute the conventional clothing design process by true designs from three-dimensional (3D) rather than two-dimensional. The aim of the research is to develop a handy 3D clothing design software tool for general garment designers. Work carried out in this paper is the preliminary result of the 3D software infrastructure. In addition, 3D collar design based on a

  8. Recovering physical property information from subduction plate boundaries using 3D full-waveform seismic inversion

    NASA Astrophysics Data System (ADS)

    Bell, R. E.; Morgan, J. V.; Warner, M.

    2013-12-01

    Our understanding of subduction margin seismogenesis has been revolutionised in the last couple of decades with the discovery that the size of the seismogenic zone may not be controlled simply by temperature and a broad spectrum of seismic behaviour exists from stick-slip to stable sliding. Laboratory and numerical experiments suggest that physical properties, particularly fluid pressure may play an important role in controlling the seismic behaviour of subduction margins. Although drilling can provide information on physical properties along subduction thrust faults at point locations at relatively shallow depths, correlations between physical properties and seismic velocity using rock physics relationships are required to resolve physical properties along the margin and down-dip. Therefore, high resolution seismic velocity models are key to recovering physical property information at subduction plate boundaries away from drill sites. 3D Full waveform inversion (FWI) is a technique pioneered by the oil industry to obtain high-resolution high-fidelity models of physical properties in the sub-surface. 3D FWI involves the inversion of low-frequency (>2 to <7 Hz), early arriving (principally transmitted) seismic data, to recover the macro (intermediate to long-wavelength) velocity structure. Although 2D FWI has been used to improve velocity models of subduction plate boundaries before, 3D FWI has not yet been attempted. 3D inversions have superior convergence and accuracy, as they sample the subsurface with multi-azimuth multiply-crossing wavefields. In this contribution we perform a suite of synthetic tests to investigate if 3D FWI could be used to better resolve physical property information along subduction margin plate boundaries using conventionally collected 3D seismic data. We base our analysis on the Muroto Basin area of the Nankai margin and investigate if the acquisition parameters and geometry of the subduction margin render 3D seismic data collected across this basin in 1999 suitable for future 3D FWI. We build a 3D model of the sub-surface based on an existing velocity model that was used to migrate these data (Tsuji et al. 2000, JGR). We then add a low P-wave velocity layer along the décollement, which is supported by ODP core data but does not feature in the current seismic velocity model, to test if it could be recovered using 3D FWI. We use the same acquisition parameters as in the 1999 seismic survey (including a 6 km long streamer) to generate a fully-elastic synthetic seismic dataset, added noise and inverted the windowed transmitted arrivals only. We also ran a suite of resolution tests across the model. The results show that 3D FWI of conventionally collected 3D seismic data across the Muroto Basin would be capable of resolving variations in P-wave velocity along the décollement of the order of half the seismic wavelength at the plate boundary. This is a significant improvement on conventional travel-time tomography which resolves to the Fresnel width. In this presentation we will also postulate on the optimal 3D FWI experiment design for the next generation of 3D seismic surveys across subduction margins as a guide for those embarking on new data collection.

  9. 3D seismic imaging, example of 3D area in the middle of Banat

    NASA Astrophysics Data System (ADS)

    Antic, S.

    2009-04-01

    3D seismic imaging was carried out in the 3D seismic volume situated in the middle of Banat region in Serbia. The 3D area is about 300 km square. The aim of 3D investigation was defining geology structures and techtonics especially in Mesozoik complex. The investigation objects are located in depth from 2000 to 3000 m. There are number of wells in this area but they are not enough deep to help in the interpretation. It was necessary to get better seismic image in deeper area. Acquisition parameters were satisfactory (good quality of input parameters, length of input data was 5 s, fold was up to 4000 %) and preprocessed data was satisfied. GeoDepth is an integrated system for 3D velocity model building and for 3D seismic imaging. Input data for 3D seismic imaging consist of preprocessing data sorted to CMP gathers and RMS stacking velocity functions. Other type of input data are geological information derived from well data, time migrated images and time migrated maps. Workflow for this job was: loading and quality control the input data (CMP gathers and velocity), creating initial RMS Velocity Volume, PSTM, updating the RMS Velocity Volume, PSTM, building the Initial Interval Velocity Model, PSDM, updating the Interval Velocity Model, PSDM. In the first stage the attempt is to derive initial velocity model as simple as possible as.The higher frequency velocity changes are obtained in the updating stage. The next step, after running PSTM, is the time to depth conversion. After the model is built, we generate a 3D interval velocity volume and run 3D pre-stack depth migration. The main method for updating velocities is 3D tomography. The criteria used in velocity model determination are based on the flatness of pre-stack migrated gathers or the quality of the stacked image. The standard processing ended with poststack 3D time migration. Prestack depth migration is one of the powerful tool available to the interpretator to develop an accurate velocity model and get good seismic image. A comparison of a time and depth migrated sections highlights the improvements in imaging quality. On depth migrated section imaging and fault resolution is improved and is easer to get more complex and realistic geological model.

  10. Internal geometry and growth history of a thrust-related anticline in a deep water fold belt

    NASA Astrophysics Data System (ADS)

    Higgins, Simon; Clarke, Benjamin; Davies, Richard J.; Cartwright, Joe

    2009-12-01

    Although 3D seismic imaging has become a fundamental tool for the analysis of extensional fault geometries and their development, it has not been utilised to the same degree to investigate the structure and growth history of thrust faults. Here, the structural evolution of a fold and thrust belt is investigated through the analysis of an isolated fold imaged in the deep water Niger Delta. A quantitative description of thrust fault displacement through transfer zones is presented to investigate the internal structure of a complex fault-related fold, while syn-kinematic growth packages are used to chart fold growth through time, so as to also understand the early growth history. Results reveal that a number of initially separate folds coalesced along the axial trends into a single structural culmination. Numerous thrust faults with similar and opposing dip, link and transfer displacement within the structure as it changes vergence along strike. The distribution of bulk deformation along the fault-related fold is simple, systematic and similar to that observed for extensional fault systems. Deficits in fault heave, both in the form of perturbations on non-linking or aggregated profiles, and displacement minima within transfer zones, are compensated to some degree by an increase in fold-related strain. Despite this accommodation, fold amplitude or crest elevation is largely unaffected by variations in fault heave. The observations for this isolated fold should be widely applicable to fold and fault development in more complex areas.

  11. Numerical homogenization for seismic wave propagation in 3D geological media

    NASA Astrophysics Data System (ADS)

    Cupillard, P.; Capdeville, Y.; Botella, A.

    2014-12-01

    Despite the important increase of the computational power in the last decades, simulating the seismic wave propagation through realistic geological models is still a challenge. By realistic models we here mean 3D media in which a broad variety (in terms of amplitude and extent) of heterogeneities lies, including discontinuities with complex geometry such as faulted and folded horizons, intrusive geological contacts and fault systems. To perform accurate numerical simulations, these discontinuities require complicated meshes which usually contain extremely small elements, yielding large, sometimes prohibitive, computation costs. Fortunately, the recent development of the non-periodic homogenization technique now enables to overcome this problem by computing smooth equivalent models for which a coarse mesh is sufficient to get an accurate wavefield. In this work, we present an efficient implementation of the technique which now allows for the homogenization of large 3D geological models. This implementation relies on a tetrahedral finite-element solution of the elasto-static equation behind the homogenization problem. Because this equation is time-independent, solving it is numerically cheaper than solving the wave equation, but it nevertheless requires some care because of the large size of the stiffness matrix arising from the fine mesh of realistic geological structures. A domain decomposition is therefore adopted. In our strategy, the obtained sub-domains overlap but they are independent so the solution within each of them can be computed either in series or in parallel. In addition, well-balanced loads, efficient search algorithms and multithreading are implemented to speed up the computation. The resulting code enables the homogenization of 3D elastic media in a time that is neglectable with respect to the simulation time of the wave propagation within. This is illustrated through a sub-surface model of the Furfooz karstic region, Belgium.

  12. Effects of fault propagation on superficial soils/gravel aquifer properties: The Chihshang Fault in Eastern Taiwan

    NASA Astrophysics Data System (ADS)

    Mu, C.; Lee, J.; guglielmi, Y.

    2013-12-01

    A mature bedrock fault zone generally consists of a fault core, a damage zone, and a surrounding host rock with different permeabilities, which mainly depend on the fracture density. However, near the surface, when an active thrust fault propagates from bedrocks into an unconsolidated surface cover, it results in a diffused fault zone, which may influence the hydraulic and mechanical properties around the fault zone. It is thus of great concern to understand to which extent surface soil/gravel hydraulic properties modifications by continuously active faulting can impact geotechnical projects in countries under active tectonic context, such as Taiwan, where active faults often are blinded beneath thick soil/gravel covers. By contrast, it is also interesting to decipher those fault-induced permeability modifications to estimate potential activity precursors to large earthquakes. Here, we combined a variety of measurements and analyses on the Chihshang fault, located at the plate suture between the Philippine Sea and Eurasian plates, which converge at a rapid rate of 8 cm/yr in Taiwan. At the Chinyuan site, the Chihshang fault is propagating from depth to emerge through thick alluvial deposits. We characterized the fault geometry and slip behavior at the shallow level by measuring and analyzing horizontal, vertical displacements, and groundwater table across the surface fault zone. The yielded fault dip of 45o in the shallow alluvium is consistent with the observations from surface ruptures and subsurface core logging. The 7-year-long groundwater table record shows that the piezometric level in the hanging wall is about 8 meter higher than that in the footwall in the summer; and about 10 meter higher in the winter. Repeated slug tests have been monthly conducted since 2007 to provide the average permeability within the fault zone and the presumably low-deformed zone outside of the diffused fault zone. Based on in-situ measurements at four wells across the fault zone, a 2-D modeling of pore pressure distribution around the fault zone is conducted using the finite-difference method (FLAC3D). The results showed that the permeability within the fault zone is 10-10 cm2 and outside of the fault zone is 10-8 cm2. The low permeable zone is estimated to be about 4-5 meters thick, and its location matches with the main fault structures mapped from geological and geodetic results. This low permeability fault zone acts as a hydraulic boundary, which explains the difference in the piezometric levels observed within the soil aquifer across the fault zone. This study provides a good natural analogue to permeability changes induced by clay smearing during soft sediments faulting. It also shows the significant impact of active thrust faults on soft sediments aquifer drainage.

  13. Local Diagnosis of Reconnection in 3D

    NASA Astrophysics Data System (ADS)

    Scudder, J. D.; Karimabadi, H.; Daughton, W. S.; Roytershteyn, V.

    2014-12-01

    We demonstrate (I,II) an approach to find reconnection sites in 3D where there is no flux function for guidance, and where local observational signatures for the ``violation of frozen flux'' are under developed, if not non-existent. We use 2D and 3D PIC simulations of asymmetric guide field reconnection to test our observational hierarchy of single spacecraft kinetic diagnostics - all possible with present state of the art instrumentation. The proliferation of turbulent, electron inertial scale layers in the realistic 3D case demonstrates that electron demagnetization, while necessary, is not sufficient to identify reconnection sites. An excellent local, observable, single spacecraft proxy is demonstrated for the size of the theoretical frozen flux violation. Since even frozen flux violations need not imply reconnection is at hand, a new calibrated dimensionless method is used to determine the importance of such violations. This measure is available in 2D and 3D to help differentiate reconnection layers from weaker frozen flux violating layers. We discuss the possibility that this technique can be implemented on MMS. A technique to highlight flow geometries conducive to reconnection in 3D simulations is also suggested, that may also be implementable with the MMS flotilla. We use local analysis with multiple necessary, but theoretically independent electron kinetic conditions to help reduce the probability of misidentification of any given layer as a reconnection site. Since these local conditions are all necessary for the site, but none is known to be sufficient, the multiple tests help to greatly reduce false positive identifications. The selectivity of the results of this approach using PIC simulations of 3D asymmetric guide field reconnection will be shown using varying numbers of simultaneous conditions. Scudder, J.D., H. Karimabadi, W. Daughton and V. Roytershteyn I, II, submitted Phys. Plasma., 2014

  14. CASPT2 study of inverse sandwich-type dinuclear 3d transition metal complexes of ethylene and dinitrogen molecules: similarities and differences in geometry, electronic structure, and spin multiplicity.

    PubMed

    Nakagaki, Masayuki; Sakaki, Shigeyoshi

    2015-07-01

    The spin multiplicities and coordination structures of inverse sandwich-type complexes (ISTCs) of ethylene and dinitrogen molecules with 3d transition metal elements (Sc to Ni), (?-C2H4)[M(AIP)]2 and (?-N2)[M(AIP)]2 (AIPH = (Z)-1-amino-3-iminoprop-1-ene; M = Sc to Ni) were investigated by the CASPT2 method. In both ethylene and dinitrogen ISTCs of the early 3d transition metals (Sc to Cr), sandwiched ethylene and dinitrogen ligands coordinate with two metal atoms in an ?(2)-side-on form and their ground states have an open-shell singlet spin multiplicity. The ?(1)-end-on coordination structure of dinitrogen ISTCs is considerably less stable than the ?(2)-side-on form in these metals. For the late 3d transition metals (Mn to Ni), ethylene and dinitrogen ISTCs exhibit interesting similarities and differences in spin multiplicity and structure as follows: in ethylene ISTCs of Mn to Ni, the ground state has an open-shell singlet spin multiplicity like those of the ISTCs of early transition metals. However, the ethylene ligand is considerably distorted, in which the ethylene carbon atoms have a tetrahedral-like structure similar to sp(3) carbon and each of them coordinates with one metal in a ?-?(1):?(1) structure. These geometrical features are completely different from those of ISTCs of the early transition metals. In dinitrogen ISTCs of Mn to Ni, on the other hand, the ground state has a high spin multiplicity from nonet (Mn) to triplet (Ni). The ?(2)-side-on coordination structure of the dinitrogen ligand is as stable as the ?(1)-end-on form in the Mn complex but the ?(1)-end-on structure is more stable than the ?(2)-side-on form in the Fe to Ni complexes. All these interesting similarities and differences between ethylene and dinitrogen ISTCs and between the early and late transition metal elements arise from the occupation of several important molecular orbitals. PMID:26041561

  15. 'Diamond' in 3-D

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This 3-D, microscopic imager mosaic of a target area on a rock called 'Diamond Jenness' was taken after NASA's Mars Exploration Rover Opportunity ground into the surface with its rock abrasion tool for a second time.

    Opportunity has bored nearly a dozen holes into the inner walls of 'Endurance Crater.' On sols 177 and 178 (July 23 and July 24, 2004), the rover worked double-duty on Diamond Jenness. Surface debris and the bumpy shape of the rock resulted in a shallow and irregular hole, only about 2 millimeters (0.08 inch) deep. The final depth was not enough to remove all the bumps and leave a neat hole with a smooth floor. This extremely shallow depression was then examined by the rover's alpha particle X-ray spectrometer.

    On Sol 178, Opportunity's 'robotic rodent' dined on Diamond Jenness once again, grinding almost an additional 5 millimeters (about 0.2 inch). The rover then applied its Moessbauer spectrometer to the deepened hole. This double dose of Diamond Jenness enabled the science team to examine the rock at varying layers. Results from those grindings are currently being analyzed.

    The image mosaic is about 6 centimeters (2.4 inches) across.

  16. Prominent rocks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Many prominent rocks near the Sagan Memorial Station are featured in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. Wedge is at lower left; Shark, Half-Dome, and Pumpkin are at center. Flat Top, about four inches high, is at lower right. The horizon in the distance is one to two kilometers away.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  17. Architect Studio 3D

    NSDL National Science Digital Library

    When one thinks of the vast number of influential architects the world has seen during the past centuries, one is reminded of Dies van der Rohe, Walter Gropius, Le Corbusier, and of course, that Master from the Midwest, Frank Lloyd Wright. It's hard to imagine that a website would be able to conjure up the spirit of this famous and controversial architect, but it does just that. With the assistance of a user-friendly interface, the Architect Studio 3D site allows users to build a model home for a number of clients and their very specific needs. With a small icon of the master residing in the bottom of the left-hand corner of the screen, visitors will get the chance to create their own building for one of these clients, and then submit it to a design gallery for consideration by others. For those visitors who may be less familiar with the world of architecture, there is a handy section titled "About Architecture". Here they will find a glossary of terms that provide brief descriptions of such important concepts and design elements as site, wall, client, roof, and exterior material. Of course, no such site would be complete without a brief biography of the man himself, and as such, a nice overview of his work and life is provided here as well.

  18. Elucidating the geometry of the active Shanchiao Fault in the Taipei metropolis, northern Taiwan, and the reactivation relationship with preexisting orogen structures

    NASA Astrophysics Data System (ADS)

    Chen, Chih-Tung; Lee, Jian-Cheng; Chan, Yu-Chang; Lu, Chia-Yu; Teng, Louis Suh-Yui

    2014-12-01

    The Shanchiao Fault is an active normal fault with documented paleoearthquakes in the Taipei metropolis, Taiwan. While posing direct seismic threat on the multimillion population, its crustal-scale fault plane configuration has not been constrained. This study presents the first attempt to resolve the fault plane dip changes of the Shanchiao Fault within the upper crust by forward modeling late Quaternary deformation. Tectonic subsidence over the last ~23 ka is estimated from vertical displacements of a rapidly formed alluvial fan horizon deformed into a dramatic rollover monocline. A 2-D profile across the Shanchiao Fault is chosen for elastic half-space dislocation modeling, and the results suggest that the fault is listric in the shallow crust with an abrupt change from subvertical ramp (85°-75°) to near-horizontal flat (10°-15°) at 3-4 km depth, consistent with an origin from the inversion of an orogen-related thrust detachment. Given the presence of rift-related fabrics in the underthrust Chinese Continental Margin basement beneath the Taiwanese orogenic wedge, listric ramp-flat-ramp models with a second deeper bend to 60° dip are also tested. Reasonable fits with the geological observations are produced when the lower ramp is located at greater than 8 km depth, which correlates with the hypocentral location of a moderate earthquake in 2004. Joint reactivation of preexisting thrust and rift faults by the Shanchiao Fault is therefore plausible with implications for seismic hazard in the Taipei area.

  19. Fault management Fault management

    E-print Network

    Fault management Pag. 1 Fault management Andrea Bianco T l i ti N t k G Network Management and Qo Torino #12;Fault management Pag. 2 The impact of network failures Cable 1101011000110101011 1 cable x 200 fibers/cable x 160 /fiber x 10 Gb/s/ = 320 Tb/s 5 billion telephone lines (@ 64 kb/s) Network Management

  20. Fault management Fault management

    E-print Network

    Fault management Pag. 1 Fault management Network Management and QoS Provisioning - 1Andrea Bianco traffic · May translate to revenue losses 5 billion telephone lines (@ 64 kb/s) 60.000 full CDs per second #12;Fault management Pag. 2 Fibers Network Management and QoS Provisioning - 4Andrea Bianco ­ TNG

  1. 3-D Cavern Enlargement Analyses

    SciTech Connect

    EHGARTNER, BRIAN L.; SOBOLIK, STEVEN R.

    2002-03-01

    Three-dimensional finite element analyses simulate the mechanical response of enlarging existing caverns at the Strategic Petroleum Reserve (SPR). The caverns are located in Gulf Coast salt domes and are enlarged by leaching during oil drawdowns as fresh water is injected to displace the crude oil from the caverns. The current criteria adopted by the SPR limits cavern usage to 5 drawdowns (leaches). As a base case, 5 leaches were modeled over a 25 year period to roughly double the volume of a 19 cavern field. Thirteen additional leaches where then simulated until caverns approached coalescence. The cavern field approximated the geometries and geologic properties found at the West Hackberry site. This enabled comparisons are data collected over nearly 20 years to analysis predictions. The analyses closely predicted the measured surface subsidence and cavern closure rates as inferred from historic well head pressures. This provided the necessary assurance that the model displacements, strains, and stresses are accurate. However, the cavern field has not yet experienced the large scale drawdowns being simulated. Should they occur in the future, code predictions should be validated with actual field behavior at that time. The simulations were performed using JAS3D, a three dimensional finite element analysis code for nonlinear quasi-static solids. The results examine the impacts of leaching and cavern workovers, where internal cavern pressures are reduced, on surface subsidence, well integrity, and cavern stability. The results suggest that the current limit of 5 oil drawdowns may be extended with some mitigative action required on the wells and later on to surface structure due to subsidence strains. The predicted stress state in the salt shows damage to start occurring after 15 drawdowns with significant failure occurring at the 16th drawdown, well beyond the current limit of 5 drawdowns.

  2. 3D Object Digitization: Majority Interpolation and Marching Cubes Peer Stelldinger

    E-print Network

    Hamburg,.Universität

    3D Object Digitization: Majority Interpolation and Marching Cubes Peer Stelldinger University-based reconstructions. 1 Introduction A lot of 3D image analysis algorithms use topologi- cal information like [4], which implies that a lot of problems in 3D digital geometry become relatively simple. The second

  3. Conformal mapping-based 3D face recognition Przemyslaw Szeptycki, Mohsen Ardabilian, Liming Chen

    E-print Network

    Conformal mapping-based 3D face recognition Przemyslaw Szeptycki, Mohsen Ardabilian, Liming Chen MI a conformal mapping-based ap- proach for 3D face recognition. The proposed approach makes use of conformal UV to conformal geometry theory, each 3D surface with disk topology can be mapped onto a 2D domain through

  4. Spherical 3D isotropic wavelets

    NASA Astrophysics Data System (ADS)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2012-04-01

    Context. Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. Aims: The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the SFB decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. Methods: We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. (2006). We also present a new fast discrete spherical Fourier-Bessel transform (DSFBT) based on both a discrete Bessel transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large box cosmological simulations and find we can successfully remove noise without much loss to the large scale structure. Results: We have described a new spherical 3D isotropic wavelet transform, ideally suited to analyse and denoise future 3D spherical cosmological surveys, which uses a novel DSFBT. We illustrate its potential use for denoising using a toy model. All the algorithms presented in this paper are available for download as a public code called MRS3D at http://jstarck.free.fr/mrs3d.html

  5. Adaptive 3D Web Sites

    Microsoft Academic Search

    Luca Chittaro; Roberto Ranon

    2007-01-01

    In recent years, technological developments have made it possible to build interactive 3D models of objects and 3D Virtual Environments that can be experienced through the Web, using common, low-cost personal computers. As in the case of Web-based hypermedia, adaptivity can play an important role in increasing the usefulness, effectiveness and usability of 3D Web sites, i.e., Web sites distributing

  6. 3D temperature model of south-western South America

    NASA Astrophysics Data System (ADS)

    Tassara, Andres; Morales, Daniel

    2013-04-01

    Temperature (T) and pressure (P) control the thermodynamics and physico-chemical behavior of Earth materials. PT conditions regulates by one side the type and relative amount of minerals forming a rock for a given chemical composition, and by the other also the physical properties of these minerals. Therefore, knowledge about the internal thermal structure of the lithosphere is fundamental in order to predict spatial variations on primary rocks properties, which further regulate the geodynamic behavior of plates, their thermomechanic configuration and tectono-magmatic evolution. Due to this fundamental role, increasing efforts are being dedicated to generate reliable models of temperature distribution inside the lithosphere for different tectonic regions of the planet. Such models should include a sufficiently large number of good-quality and well-distributed surface heat flow measurements that can be used to invert geothermal gradients. However, most of the world, including the south-western margin of South America, lack such measurements and other indirect approaches must be applied in order to derive the thermal structure. Here we present a regional-scale thermal model for the Andean margin between 18°S and 45°S. This model is based on an exisiting 3D geological model for this region that unifies a large geophysical database (seismicity, 2D and 3D seismic velocity models, receiver functions, land- and satellite-derived gravity) into a lithospheric-scale representation of the geometry for main geotectonic discontinuities like the subducted slab upper surface, the lithosphere-astenosphere boundary (LAB), continental crust-mantle boundary (Moho) and intracurstal discontinuity (ICD). From a regularly gridded interpolation of these geometries at a spatial resolution of 15 km, we computed at each grid node a 1D geothermal gradient that we then merged to create the 3D thermal structure. We assume that the lithosphere geotherm is defined by heat conduction with radioactive heat production regulated by the compositional structure of crust and mantle, and impose that the temperature at the base of the continental lithosphere is dictated by a particular condition. For the region east to the intersection of LAB with the subducted slab, we assume that the LAB correspond to the intersection of a adiabatic astenosphere with the conductive lithosphere and take its temperature as defined by the potential temperature of the adiabat at the surface and a constant adiabatic gradient. The thermal structure at the forearc region to the west of LAB-Slab intersection is defined by the temperature at the plate interface, which we compute considering the heat flow coming from the subducted plate, fault friction and a reduction factor that depends on convergence velocity and subduction geometry. We have tested different combinations of the many parameters involved in defining the model and compared the resulting values of surface heat flow against a compiltation of measurements in order to evaluate the performance of the models. Our preferred model fits most of the data and we will show here some examples of the usefulness of the model for estimating the geothermal energy potential of the region and the understanding of the thermomechanic behavior of the lithosphere in relation with active magmatism and tectonics.

  7. E3D, The Euro3D Visualization Tool

    NASA Astrophysics Data System (ADS)

    Sánchez, S. F.

    2004-07-01

    We present the first version of E3D, the Euro3D visualization tool for data from integral field spectroscopy. We describe its major characteristics, based on the proposed requirements, the current state of the project, and some planned future upgrades. We show examples of its use and capabilities.

  8. E3D, The Euro3D Visualization Tool

    Microsoft Academic Search

    S. F. Sánchez

    2004-01-01

    We present the first version of E3D, the Euro3D visualization tool for data from integral field spectroscopy. We describe its major characteristics, based on the proposed requirements, the current state of the project, and some planned future upgrades. We show examples of its use and capabilities.

  9. 3D Ear Print Authentication using 3D Radon Transform

    Microsoft Academic Search

    W. A. Mahmoud; M. R. Shaker

    2006-01-01

    This paper introduces a proposed method authentication based upon 3D Radon transform. It considers the three dimensional ear of human as a personal identification number. Next, it produces the required features using the 3D Radon transform. This transform is adapted from its 2D form to adequate this application. The neural network was used in the identification phase, the evaluation test

  10. Pointshop 3D: An Interactive System for Point-Based Surface Editing Matthias Zwicker Mark Pauly Oliver Knoll Markus Gross

    E-print Network

    Zwicker, Matthias

    for user guided alteration of 2D image data. In recent years advances in 3D digital photography spawned 2D photo editing to make it amena- ble to 3D photography. While existing 3D geometry-oriented modPointshop 3D: An Interactive System for Point-Based Surface Editing Matthias Zwicker Mark Pauly

  11. A multidisciplinary study of a syntectonic pluton close to a major lithospheric-scale fault—Relationships between the Montmarault granitic massif and the Sillon Houiller Fault in the Variscan French Massif Central: 2. Gravity, aeromagnetic investigations, and 3-D geologic modeling

    Microsoft Academic Search

    Aurore Joly; Guillaume Martelet; Yan Chen; Michel Faure

    2008-01-01

    New gravity and aeromagnetic investigations have been carried out to understand the emplacement mechanisms of a granitic pluton and the relationships with a nearby lithospheric-scale fault. This paper concerns the second part of a methodological multidisciplinary study and complements previous geochronologic and Anisotropy of Magnetic Susceptibility (AMS) studies on the same pluton. In the northern part of the Variscan French

  12. Fault zone structure of the Wildcat fault in Berkeley, California - Field survey and fault model test -

    NASA Astrophysics Data System (ADS)

    Ueta, K.; Onishi, C. T.; Karasaki, K.; Tanaka, S.; Hamada, T.; Sasaki, T.; Ito, H.; Tsukuda, K.; Ichikawa, K.; Goto, J.; Moriya, T.

    2010-12-01

    In order to develop hydrologic characterization technology of fault zones, it is desirable to clarify the relationship between the geologic structure and hydrologic properties of fault zones. To this end, we are performing surface-based geologic and trench investigations, geophysical surveys and borehole-based hydrologic investigations along the Wildcat fault in Berkeley,California to investigate the effect of fault zone structure on regional hydrology. The present paper outlines the fault zone structure of the Wildcat fault in Berkeley on the basis of results from trench excavation surveys. The approximately 20 - 25 km long Wildcat fault is located within the Berkeley Hills and extends northwest-southeast from Richmond to Oakland, subparallel to the Hayward fault. The Wildcat fault, which is a predominantly right-lateral strike-slip fault, steps right in a releasing bend at the Berkeley Hills region. A total of five trenches have been excavated across the fault to investigate the deformation structure of the fault zone in the bedrock. Along the Wildcat fault, multiple fault surfaces are branched, bent, paralleled, forming a complicated shear zone. The shear zone is ~ 300 m in width, and the fault surfaces may be classified under the following two groups: 1) Fault surfaces offsetting middle Miocene Claremont Chert on the east against late Miocene Orinda formation and/or San Pablo Group on the west. These NNW-SSE trending fault surfaces dip 50 - 60° to the southwest. Along the fault surfaces, fault gouge of up to 1 cm wide and foliated cataclasite of up to 60 cm wide can be observed. S-C fabrics of the fault gouge and foliated cataclasite show normal right-slip shear sense. 2) Fault surfaces forming a positive flower structure in Claremont Chert. These NW-SE trending fault surfaces are sub-vertical or steeply dipping. Along the fault surfaces, fault gouge of up to 3 cm wide and foliated cataclasite of up to 200 cm wide can be observed. S-C fabrics of the fault gouge and foliated cataclasite show reverse right-slip shear sense. We are performing sandbox experiments to investigate the three-dimensional kinematic evolution of fault systems caused by oblique-slip motion. The geometry of the Wildcat fault in the Berkeley Hills region shows a strong resemblance to our sandbox experimental model. Based on these geological and experimental data, we inferred that the complicated fault systems were dominantly developed within the fault step and the tectonic regime switched from transpression to transtension during the middle to late Miocene along the Wildcat fault.

  13. 3D fracture zon network in the crystalline geothermal reservoir of Soultz-sous-Forêts (Upper Rhine Graben, France)

    NASA Astrophysics Data System (ADS)

    Dezayes, C.; Sausse, J.; Genter, A.

    2009-04-01

    The Soultz experimental geothermal site is located in the French part of the Upper Rhine Graben, nearby its western regional boundary fault. The structure of the granite reservoir is constituted by both a nearly vertical major fracture zone network, connected to a dense network of small-scale fractures. Fracture zones are complex brecciated and fractured zones having irregular shape. The permeability of these fracture zones could be enhanced by hydraulic/chemical stimulations. They constitute the major pathways and their characterization is of prime importance for the reservoir knowledge. Based on borehole data of the Soultz geothermal site, 39 fracture zones have been characterized in six wells between 1400 and 5000m depth. The direction of the major set of fracture zone is N160°E±10° with high dip westward and eastward. These fracture zones are spatially concentrated in three clusters with depth. The upper cluster at 1800-2000m TVD (True Vertical Depth) is highly naturally permeable and mainly dipping to the East. At 3000-3400m TVD, the intermediate cluster constitutes a dense network developed in an altered matrix and constituted the upper reservoir. In the lower part of the wells, the deeper cluster appears as a fractured reservoir corresponding to isolated discrete faults developed within a low permeable matrix at about 4500-5000m TVD. In the two deep clusters, fracture zones are mainly dipping to the West. The geometry of these fracture zones has been integrated in a 3D model, in addition with the location of induced microseismicity as well as structures derived from vertical seismic profile (VSP) data interpretation. This 3D representation allows correlating geophysical and geological data in order to illustrate the complexity of 3D fracture network in crystalline rocks characterized at borehole scale (meter) and extended in 3D at reservoir scale (kilometer).

  14. Computer Simulations of Pulsatile Human Blood Flow Through 3D-Models of the Human Aortic Arch, Vessels of Simple Geometry and a Bifurcated Artery: Investigation of Blood Viscosity and Turbulent Effects

    E-print Network

    Sultanov, Renat A

    2008-01-01

    We report computational results of blood flow through a model of the human aortic arch and a vessel of actual diameter and length. On the top of the aortic arch the branching of the %%three arteries are included: the subclavian and jugular. A realistic pulsatile flow is used in all simulations. Calculations for bifurcation type vessels are also carried out and presented. Different mathematical methods for numerical solution of the fluid dynamics equations have been considered. The non-Newtonian behaviour of the human blood is investigated together with turbulence effects. A detailed time-dependent mathematical convergence test has been carried out. The results of computer simulations of the blood flow in vessels of three different geometries are presented: for pressure, strain rate and velocity component distributions we found significant disagreements between our results obtained with realistic non-Newtonian treatment of human blood and the widely used method in the literature: a simple Newtonian approximati...

  15. Microearthquakes illuminate the deep structure of the endglacial Pärvie fault, northern Sweden

    NASA Astrophysics Data System (ADS)

    Lindblom, Eva; Lund, Björn; Tryggvason, Ari; Uski, Marja; Bödvarsson, Reynir; Juhlin, Christopher; Roberts, Roland

    2015-06-01

    At 155 km, the Pärvie fault is the world's longest known endglacial fault (EGF). It is located in northernmost Sweden in a region where several kilometre-scale EGFs have been identified. Based on studies of Quaternary deposits, landslides and liquefaction structures, these faults are inferred to have ruptured as large earthquakes when the latest ice sheet disappeared from the region, some 9500 yr ago. The EGFs still exhibit relatively high seismic activity, and here we present new earthquake data from northern Sweden in general and the Pärvie fault in particular. More than 1450 earthquakes have been recorded in Sweden north of 66° latitude in the years 2000-2013. There is a remarkable correlation between this seismicity and the mapped EGF scarps. We find that 71 per cent of the observed earthquakes north of 66° locate within 30 km to the southeast and 10 km to the northwest of the EGFs, which is consistent with the EGFs' observed reverse faulting mechanisms, with dips to the southeast. In order to further investigate the seismicity along the Pärvie fault we installed a temporary seismic network in the area between 2007 and 2010. In addition to the routine automatic detection and location algorithm, we devised a waveform cross-correlation technique which resulted in a 50 per cent increase of the catalogue and a total of 1046 events along the Pärvie fault system between 2003 and 2013. The earthquakes were used to establish an improved velocity model for the area, using 3-D local earthquake tomography. The resulting 3-D velocity model shows smooth, minor velocity variations in the area. All events were relocated in this new 3-D model. A tight cluster on the central part of the Pärvie fault, where the rate of seismicity is the highest, could be relocated with high precision relative location. We performed depth phase analysis on 40 of the larger events to further constrain the hypocentral locations. We find that the seismicity on the Pärvie fault correlates very well with the mapped surface trace of the fault. The events do not align along a well-defined fault plane at depth but form a zone of seismicity that dips between 30° and 60° to the southeast of the surface fault trace, with distinct along-strike variations. The seismic zone extends to approximately 35 km depth. Using this geometry and earthquake scaling relations, we estimate that the endglacial Pärvie earthquake had a magnitude of 8.0 ± 0.4.

  16. Co-seismic reverse- and oblique-slip surface faulting generated by the 2008 Mw 7.9 Wenchuan earthquake, China

    NASA Astrophysics Data System (ADS)

    Xiwei, X.; Xueze, W.; Guihua, Y.; Guihua, C.; Klinger, Y.

    2008-12-01

    Field investigations show that the Mw 7.9 Wenchuan earthquake on 12th May 2008 ruptured two NW-dipping imbricate reverse faults along the Longmenshan thrust fault zone at the eastern margin of the Tibetan plateau. This earthquake produced a 240-km-long surface rupture zone along the Beichuan fault characterized by right-lateral oblique faulting and a 72-km-long surface rupture zone along the Pengguan fault characterized by dip-slip reverse faulting. Maximum vertical and horizontal dispacements of 6.2 m and 4.9 m, respectively, were observed along the Beichuan fault, whereas a maximum vertical displacement of 3.5 m occurred along the Pengguan fault. This co-seismic surface rupture pattern, involving multiple structures, is among the most complicated of recent great earthquakes and its surface rupture length is the longest among the co-seismic surface rupture zones for reverse faulting events ever reported in the intraplate setting. A 3D model for the rupture geometry shows crustal shortening to be the dominant process along the Longmenshan thrust fault zone to accommodate long-term deformation. Thus, oblique thrusting accomplished by the earthquake indicates that the east-southeastward extrusion of Tibet Plateau accommodates, in part, the continuing penetration of the Indian plate into the Eurasian plate, and this extrusion is transformed at the eastern margin of the Tibetan Plateau into crustal thickening and shortening that is responsible for the growth of high topography in the region.

  17. Geomorphological maps and 3d models in cave research

    NASA Astrophysics Data System (ADS)

    Ballesteros, Daniel; Jiménez-Sánchez, Montserrat; José Domínguez-Cuesta, María

    2013-04-01

    Cave geomorphological processes and features can be studied by geomorphological maps although topographic maps, aerial photos and GPS are not available. Methods in cave geomorphological mapping are conditioned by cave environment configuration, the need of using speleological techniques, and limitations arising from the projection of the 3D data from the cave to a 2D plan. Some of our previous works in the Cantabrian Mountains and Cantabrian Coast (NW Spain) established the approach of the design of cave geomorphological maps and its legend. Today we are improving the display of cave process combining geomorphological maps and 3d models based on the experience obtained from the research of one cave from the Cantabrian Coast and four caves in the Picos de Europa National Park (funded by GEOCAVE project, Spanish National Parks Agency). The five caves are developed in Carboniferous limestone affected by faults and thrusts. The method of work includes: 1) the elaboration of the cave survey at 1:50 to 1:500 scale; 2) the check of the cave survey of three caves by closed loops; 3) the mapping of cave features based on the performed survey; 4) the 3d modeling of the caves approximating each survey shoot by an octagonal prism; and 5) the implementation and management of the survey and geomorphological map in a Geographic Information System. Based on the survey, the cavities are small caves to deep alpine shafts with 281 to 4,438 m length and up to 738 m deep. The precision of the cave maps only could be estimated in two caves at a cavity scale, displaying both of them a 2.49 % error. The prisms of the 3d model was classified into four groups according to the morphology of the cave passage: 1) canyons, 2) phreatic and epiphreatic tubes, 3) soutirage conduits, 4) mixed forms composed by phreatic and epiphreatic tubes modified by fluvial incision, 5) pitches and 6) irregular passages enlarged strongly by gravity process. According to our previous works geomorphological features were classified using genetic and morphological criteria in four groups: 1) fluviokarst features; 2) speleothems; 3) gravity forms; and 4) anthropogenic features. Canyons passages usually include vadose erosive forms and few dripstones and flowstones; the phreatic and epiphreatic tubes frequently display many phreatic erosive features, fluvial and torrential deposits, flowstone, dripstone and few and small breakdown deposits; the soutirage conduits shows phreatic erosive features and few dripstone and gravity deposit removed from upper passages; the mixed forms combine the features of canyons and phreatic and epiphreatic tubes detailed above; the pitches display small dripstone and flowstone in the walls and gravity deposits or vadose erosive forms in its bottom; and the passages enlarged strongly by gravity process contain big talus deposits and some small slides that modified previous fluviokarst and speleothems features. Consequently, the results evidence that the geometry and geomorphology of the cavities can be defined together combining the geomorphological maps and 3d model in order to link the morphology of the conduits with the cave processes.

  18. Probabilistic Fault Displacement Hazard Assessment For Pipelines, Mad Dog and Atlantis Field Developments, Deepwater Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Angell, M.; Hanson, K.; Swan, F.; Youngs, R.; Abramson, H.

    2004-12-01

    Seafloor faults having strong geomorphic expression and evidence for late Quaternary activity (i.e. < ~150,000 years) are common geologic features associated with the Sigsbee Escarpment. Waterbottom maps derived from exploration 3D multichannel seismic data provided an early indication that several zones of seafloor faults are in the vicinity of the Mad Dog and Atlantis prospect areas. As part of the site investigation activities for field development BP initiated a study to characterize the potential hazard due to fault displacement. The fault displacement hazard study consists of five components: 1) a site-wide structural geologic characterization of the style and origin of active faulting and fault-related deformation; 2) development of a late Quaternary stratigraphic model to evaluate the history, recency, and rate of fault activity at the site; 3) detailed characterization of faulting within limited study areas designated to capture fault behavior in areas of potential facilities development; 4) a general description of the relationship between Quaternary active faulting and slope failure processes within the field area; and 5) a probabilistic fault displacement hazard analysis (PFDHA) of the potential for fault rupture within the designated study areas that relates annual frequency of recurrence of faulting events to the size of the event. Changes in the style and origin of faulting and deformation of shallow (suprasalt) sediment across the individual field areas primarily is due to differences in the depth, geometry, and movement history of the underlying Sigsbee Salt Nappe. These relationships and the resulting geologic model for structural evolution of the suprasalt section has been used effectively to assess the site-wide geohazards not only for faulting, but also indirectly for slope failure and mass-gravity flows. Hazard from potential seafloor offset at fault crossings is judged to be moderate to low. Fault offsets of the shallowest horizons (less than 15 thousand years old) are typically less than ten meters to several tens of meters. Fault slip rates are on the order of tenths to several tens of meters-per-thousand-years (m/kyr, also millimeters-per-year, or mm/yr), with most values in the range of 2-10 m/kyr. Similarly, the probabilistic annual recurrence of 1-meter events is typically less than 10-3. These studies demonstrate that the presence of potentially active faults does not preclude safe development of seafloor facilities. To evaluate risk associated with potential seafloor faulting, integrated hazard studies can and should be conducted in the early stages of project development, with an underlying intent to understand the causative processes and quantitatively and explicitly evaluate the locations, magnitude and recurrence potential of displacement events.

  19. Scalable singular 3D modeling for digital battlefield applications

    NASA Astrophysics Data System (ADS)

    Jannson, Tomasz P.; Ternovskiy, Igor V.

    2000-10-01

    We propose a new classification algorithm to detect and classify targets of interest. It is based on an advanced brand of analytic geometry of manifolds, called theory of catastrophes. Physical Optics Corporation's (POC) scalable 3D model representation provides automatic and real-time analysis of a discrete frame of a sensed 2D imagery of terrain, urban, and target features. It then transforms this frame of discrete different-perspective 2D views of a target into a 3D continuous model called a pictogram. The unique local stereopsis feature of this modeling is the surprising ability to locally obtain a 3D pictogram from a single monoscopic photograph. The proposed 3D modeling, combined with more standard change detection algorithms and 3D terrain feature models, will constitute a novel classification algorithm and a new type of digital battlefield imagery for Imaging Systems.

  20. A 3-D SAR approach to IFSAR processing

    SciTech Connect

    DOERRY,ARMIN W.; BICKEL,DOUGLAS L.

    2000-03-01

    Interferometric SAR (IFSAR) can be shown to be a special case of 3-D SAR image formation. In fact, traditional IFSAR processing results in the equivalent of merely a super-resolved, under-sampled, 3-D SAR image. However, when approached as a 3-D SAR problem, a number of IFSAR properties and anomalies are easily explained. For example, IFSAR decorrelation with height is merely ordinary migration in 3-D SAR. Consequently, treating IFSAR as a 3-D SAR problem allows insight and development of proper motion compensation techniques and image formation operations to facilitate optimal height estimation. Furthermore, multiple antenna phase centers and baselines are easily incorporated into this formulation, providing essentially a sparse array in the elevation dimension. This paper shows the Polar Format image formation algorithm extended to 3 dimensions, and then proceeds to apply it to the IFSAR collection geometry. This suggests a more optimal reordering of the traditional IFSAR processing steps.

  1. Structural Architecture and Evolutionary Plate-Boundary Processes along the San Jacinto Fault Zone

    NASA Astrophysics Data System (ADS)

    Ben-Zion, Y.

    2012-12-01

    Problems of continental dynamics are typically studied with frameworks that assume smooth continuous processes. Such models provide important insights on large-scale phenomena far from plate boundaries, but they are not useful near the plate boundaries themselves where deformation processes and structures exhibit highly episodic, complex, and ultimately localized patterns in space and time. In such regions small and large scale structural features develop in the brittle crust by the accumulation of slip on seismogenic faults. An understanding of continental dynamics near plate boundaries requires an approach that accounts explicitly for the interplay between earthquakes and fault evolution. Seismic ruptures lead to the modification of the geometry, internal structure and material properties of fault zones. Conversely, the nucleation, growth and arrest of earthquake ruptures, seismic radiation, inter- and post-seismic deformation, and local seismicity patterns are controlled by the fault zone structure. To address these feedback mechanisms it is important to study the coupled evolution of earthquakes and faults. This is done with funding from the CD program of NSF in the context of the San Jacinto fault zone and surrounding environment in southern California. The project includes collection, analyses and joint interpretation of seismic, geodetic and geological data within and around the internal structure of the San Jacinto fault zone. Recent results include detailed tomographic images of fault zone damage, bimaterial interfaces and basins in the fault zone area, earthquake source properties in different fault sections, analysis of geodetic data accounting for the 3D variations of elastic moduli in the tomographic images, detailed geological mapping of rock damage, paleoseismic records at several sites along the fault, and computer simulations of long seismic catalogs that account for the available seismic and geological data. Examples results will be presented in the meeting.

  2. Fault Parameters of The 1999 Izmit Earthquake Inferred From Accerelogram Near The Fault

    NASA Astrophysics Data System (ADS)

    Aochi, H.; Madariaga, R.

    We simulated the dynamic rupture process and seismic wave propagation of the 1999 Izmit, Turkey, earthquake, using a 3D boundary integral equation method (BIEM) and a finite difference method (FDM). Although we have to know a priori the initial situation (fault geometry, frictional parameters, tectonic stress, etc) for accomplishing numerical simulation, it is still difficult to decide them quantitatively and reasonably. In this work, we aim to look for a better modeling by trying different fault models and parameters and then by comparing seismograms. Especially we focus on one of the seismic stations, SKR (Sakarya), which is located just a few km apart from the fault. The record of SKR in the EW component shows briefly an envelope of the waveform in the positive (east) direction. The maximum velocity was more than 80 cm/s and its duration was several seconds. This suggest a strong rupture passage with high speed as shown in seismic inversion result (Bouchon et al., 2001). For the purpose reproducing waveform envelopes, rupture should propagate smoothly and continuously along the fault. This also infers that a fault should be rather smooth and continuous beneath the Sapanca lake, although some geological survey of fault trace infers a discrepancy at this point. Next, in order to explain large velocity ampli- tudes, we need a large slip area around the ground surface. This also requires a few MPa cohesive force in friction law at the surface. Finally, short duration of waveform implies a rapid passage of rupture. This behavior should be strongly dependent on frictional parameters. When we take slip-weakening distance larger than 1 m, the du- ration becomes more than 10-15 seconds. We estimate it to be less than 0.8 m. But this estimation is not very strict. For calculating small slip-weakening distance, we need a better resolution in the numerical simulation.

  3. Fault Motion

    NSDL National Science Digital Library

    This collection of animations provides elementary examples of fault motion intended for simple demonstrations. Examples include dip-slip faults (normal and reverse), strike-slip faults, and oblique-slip faults.

  4. Analysis of surface structures of major strike-slip faults

    NASA Astrophysics Data System (ADS)

    Hsieh, Shang Yu; Neubauer, Franz

    2013-04-01

    Strike-slip faults commonly appear with complex fractures and deformation structures on the surface, which also reveal the 3-D geometry with variable structures at depth. The aim of our study is finding the systematic features and correlations of various surface expressions including width, length, height and angle (to the main fault trace) of individual structures like pressure ridges, sag ponds, riedel and anti-riedel faults and oversteps, and also doing a classification with these data. The variation might by caused by distinct convergence angles along strike-slip fault. We study the above mentioned properties on Altyn Tagh fault (ATF), Kunlun, San Andrea and Greendale (Darfield earthquake) faults, which are large strike-slip tectonic structures accommodating major displacement along plate boundaries. Especially the recent events of 2001 Kunlun earthquake and 2010 Darfield earthquake allow a detailed study of structures formed by a single earthquake. Along the fault valley of a 610 km segment of ATF, many large-scale pressure ridges, few pressure basins and horizontal offsets of wadi channels were found; similarly, around 20 features with large scale pressure ridges and pressure basins are found in Carrizo Plain of San Andreas fault. Surface ruptures are uncommon, and dominated by anti-riedels in the case of the Altyn fault. Interpretations show the range of length, width and height in pressure ridges located between 150 and ~6400 m, 35 and ~800 m, and 1 to ~80 m, respectively, along ATF and 255 to ~5750 m, 33 to ~800 m, 2 to ~65 m in Carrizo plain of San Andreas fault. These parameters exhibit a good correlation among each other implying a common cause. Compared with these two strike-slip faults, fault valley portions of the Greendale and Kunlun faults show more surface ruptures for instance riedel shears and anti-riedel structures, which have been caused by the last major earthquake, and also the scale of deformations along the ATF and San Andreas fault is much larger by numerous cumulative earthquakes. Surface ruptures has certain length and width of 5 m to ~200 m, 3 to ~350 m in the Kunlun fault (Lin and Nishikawa, 2011) and 10 to ~450 m, 30 to ~300 m in Greendale fault (Quigley et al., 2012). Beside the scale difference, the statistical approach also applied in the parameters of these surface features, result shows in these four faults, there are specific correlations exist among lengths, width, height and convergence angle which is also the key point to explore the depth of these structures with analog experiments. A likely explanation for the differences between Altyn/San Andreas faults and Kunlun/Glendale fault is the transpressive nature of Altyn/San Andreas faults and the pure strike-slip/transform nature of Glendale/Kunlun faults implying a small convergence angle in the latter case.

  5. Modular 3-D Transport model

    EPA Science Inventory

    MT3D was first developed by Chunmiao Zheng in 1990 at S.S. Papadopulos & Associates, Inc. with partial support from the U.S. Environmental Protection Agency (USEPA). Starting in 1990, MT3D was released as a pubic domain code from the USEPA. Commercial versions with enhanced capab...

  6. Market study: 3-D eyetracker

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A market study of a proposed version of a 3-D eyetracker for initial use at NASA's Ames Research Center was made. The commercialization potential of a simplified, less expensive 3-D eyetracker was ascertained. Primary focus on present and potential users of eyetrackers, as well as present and potential manufacturers has provided an effective means of analyzing the prospects for commercialization.

  7. Spherical 3D Isotropic Wavelets

    E-print Network

    Lanusse, F; Starck, J -L

    2011-01-01

    Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D Spherical Fourier-Bessel (SFB) analysis in is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the Fourier-Bessel decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. 2006. We also present a new fast Discrete Spherical Fourier-Bessel Transform (DSFBT) based on both a discrete Bessel Transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large...

  8. The 3D geological model of the 1963 Vajont rockslide, reconstructed with implicit surface methods

    NASA Astrophysics Data System (ADS)

    Bistacchi, Andrea; Massironi, Matteo; Francese, Roberto; Giorgi, Massimo; Taller, Claudio

    2015-04-01

    The Vajont rockslide has been the object of several studies because of its catastrophic consequences and of its particular evolution. Several qualitative or quantitative models have been presented in the last 50 years, but a complete explanation of all the relevant geological and mechanical processes remains elusive. In order to better understand the mechanics and dynamics of the 1963 event, we have reconstructed the first 3D geological model of the rockslide, which allowed us to accurately investigate the rockslide structure and kinematics. The input data for the model consisted in: pre- and post-rockslide geological maps, pre- and post-rockslide orthophotos, pre- and post-rockslide digital elevation models, structural data, boreholes, and geophysical data (2D and 3D seismics and resistivity). All these data have been integrated in a 3D geological model implemented in Gocad®, using the implicit surface modelling method. Results of the 3D geological model include the depth and geometry of the sliding surface, the volume of the two lobes of the rockslide accumulation, kinematics of the rockslide in terms of the vector field of finite displacement, and high quality meshes useful for mechanical and hydrogeological simulations. The latter can include information about the stratigraphy and internal structure of the rock masses and allow tracing the displacement of different material points in the rockslide from the pre-1963-failure to the post-rockslide state. As a general geological conclusion, we may say that the 3D model allowed us to recognize very effectively a sliding surface, whose non-planar geometry is affected by the interference pattern of two regional-scale fold systems. The rockslide is partitioned into two distinct and internally continuous rock masses with a distinct kinematics, which were characterised by a very limited internal deformation during the slide. The continuity of these two large blocks points to a very localized deformation, occurring along a thin, continuous and weak cataclastic horizon. Finally, the chosen modelling strategy, based on both traditional "explicit" and implicit techniques, was found to be very effective for reconstructing complex folded and faulted geological structures, and could be applied also to other geological environments.

  9. Euro3D Science Conference

    NASA Astrophysics Data System (ADS)

    Walsh, J. R.

    2004-02-01

    The Euro3D RTN is an EU funded Research Training Network to foster the exploitation of 3D spectroscopy in Europe. 3D spectroscopy is a general term for spectroscopy of an area of the sky and derives its name from its two spatial + one spectral dimensions. There are an increasing number of instruments which use integral field devices to achieve spectroscopy of an area of the sky, either using lens arrays, optical fibres or image slicers, to pack spectra of multiple pixels on the sky (``spaxels'') onto a 2D detector. On account of the large volume of data and the special methods required to reduce and analyse 3D data, there are only a few centres of expertise and these are mostly involved with instrument developments. There is a perceived lack of expertise in 3D spectroscopy spread though the astronomical community and its use in the armoury of the observational astronomer is viewed as being highly specialised. For precisely this reason the Euro3D RTN was proposed to train young researchers in this area and develop user tools to widen the experience with this particular type of data in Europe. The Euro3D RTN is coordinated by Martin M. Roth (Astrophysikalisches Institut Potsdam) and has been running since July 2002. The first Euro3D science conference was held in Cambridge, UK from 22 to 23 May 2003. The main emphasis of the conference was, in keeping with the RTN, to expose the work of the young post-docs who are funded by the RTN. In addition the team members from the eleven European institutes involved in Euro3D also presented instrumental and observational developments. The conference was organized by Andy Bunker and held at the Institute of Astronomy. There were over thirty participants and 26 talks covered the whole range of application of 3D techniques. The science ranged from Galactic planetary nebulae and globular clusters to kinematics of nearby galaxies out to objects at high redshift. Several talks were devoted to reporting recent observations with newly completed 3D instruments - CIRPASS, GMOS, PMAS and SPIFFI. Work on 3D software, being developed as part of the Euro3D RTN, was also described and demonstrated. This proceedings volume, consisting of carefully refereed and edited manuscripts, represents the bulk of the talks at the conference and amply demonstrates that 3D spectroscopy is a lively and burgeoning field of optical observation.

  10. Basin geometry and cumulative offsets in the Eastern Transverse Ranges, southern California: Implications for transrotational deformation along the San Andreas fault system

    USGS Publications Warehouse

    Langenheim, V.E.; Powell, R.E.

    2009-01-01

    The Eastern Transverse Ranges, adjacent to and southeast of the big left bend of the San Andreas fault, southern California, form a crustal block that has rotated clockwise in response to dextral shear within the San Andreas system. Previous studies have indicated a discrepancy between the measured magnitudes of left slip on through-going east-striking fault zones of the Eastern Transverse Ranges and those predicted by simple geometric models using paleomagnetically determined clockwise rotations of basalts distributed along the faults. To assess the magnitude and source of this discrepancy, we apply new gravity and magnetic data in combination with geologic data to better constrain cumulative fault offsets and to define basin structure for the block between the Pinto Mountain and Chiriaco fault zones. Estimates of offset from using the length of pull-apart basins developed within left-stepping strands of the sinistral faults are consistent with those derived by matching offset magnetic anomalies and bedrock patterns, indicating a cumulative offset of at most ???40 km. The upper limit of displacements constrained by the geophysical and geologic data overlaps with the lower limit of those predicted at the 95% confidence level by models of conservative slip located on margins of rigid rotating blocks and the clockwise rotation of the paleomagnetic vectors. Any discrepancy is likely resolved by internal deformation within the blocks, such as intense deformation adjacent to the San Andreas fault (that can account for the absence of basins there as predicted by rigid-block models) and linkage via subsidiary faults between the main faults. ?? 2009 Geological Society of America.

  11. Integrating Automated Range Registration with Multiview Geometry for the Photorealistic Modeling

    E-print Network

    Stamos, Ioannis

    photography. This paper presents a system that integrates automated 3D-to-3D and 2D-to-3D registra- tion techniques, with multiview geometry for the photorealistic modeling of urban scenes. The 3D range scans are registered using our automated 3D-to-3D registra- tion method that matches 3D features (linear or circular

  12. A “mesh” of crossing faults: Fault networks of southern California

    NASA Astrophysics Data System (ADS)

    Janecke, S. U.

    2009-12-01

    Detailed geologic mapping of active fault systems in the western Salton Trough and northern Peninsular Ranges of southern California make it possible to expand the inventory of mapped and known faults by compiling and updating existing geologic maps, and analyzing high resolution imagery, LIDAR, InSAR, relocated hypocenters and other geophysical datasets. A fault map is being compiled on Google Earth and will ultimately discriminate between a range of different fault expressions: from well-mapped faults to subtle lineaments and geomorphic anomalies. The fault map shows deformation patterns in both crystalline and basinal deposits and reveals a complex fault mesh with many curious and unexpected relationships. Key findings are: 1) Many fault systems have mutually interpenetrating geometries, are grossly coeval, and allow faults to cross one another. A typical relationship reveals a dextral fault zone that appears to be continuous at the regional scale. In detail, however, there are no continuous NW-striking dextral fault traces and instead the master dextral fault is offset in a left-lateral sense by numerous crossing faults. Left-lateral faults also show small offsets where they interact with right lateral faults. Both fault sets show evidence of Quaternary activity. Examples occur along the Clark, Coyote Creek, Earthquake Valley and Torres Martinez fault zones. 2) Fault zones cross in other ways. There are locations where active faults continue across or beneath significant structural barriers. Major fault zones like the Clark fault of the San Jacinto fault system appears to end at NE-striking sinistral fault zones (like the Extra and Pumpkin faults) that clearly cross from the SW to the NE side of the projection of the dextral traces. Despite these blocking structures, there is good evidence for continuation of the dextral faults on the opposite sides of the crossing fault array. In some instances there is clear evidence (in deep microseismic alignments of hypocenters) that the master dextral faults zones pass beneath shallower crossing fault arrays above them and this mechanism may transfer strain through the blocking zones. 3) The curvature of strands of the Coyote Creek fault and the Elsinore fault are similar along their SE 60 km. The scale, locations and concavity of bends are so similar that their shape appears to be coordinated. The matching contractional and extensional bends suggests that originally straighter dextral fault zones may be deforming in response of coeval sinistral deformation between, beneath, and around them. 4) Deformation is strongly domainal with one style or geometry of structure dominating in one area then another in an adjacent area. Boundaries may be abrupt. 5) There are drastic lateral changes in the width of damage zones adjacent to master faults. Outlines of the deformation related to some dextral fault zones resemble a snake that has ingested a squirming cat or soccer ball. 6) A mesh of interconnected faults seems to transfer slip back and forth between structures. 7) Scarps are not necessarily more abundant on the long master faults than on connector or crossing faults. Much remains to be learned upon completion the fault map.

  13. The role of mechanical heterogeneities during continental breakup: a 3D lithospheric-scale modelling approach

    NASA Astrophysics Data System (ADS)

    Duclaux, Guillaume; Huismans, Ritske S.; May, Dave

    2015-04-01

    How and why do continents break? More than two decades of analogue and 2D plane-strain numerical experiments have shown that despite the origin of the forces driving extension, the geometry of continental rifts falls into three categories - or modes: narrow rift, wide rift, or core complex. The mode of extension itself is strongly influenced by the rheology (and rheological behaviour) of the modelled layered system. In every model, an initial thermal or mechanical heterogeneity, such as a weak seed or a notch, is imposed to help localise the deformation and avoid uniform stretching of the lithosphere by pure shear. While it is widely accepted that structural inheritance is a key parameter for controlling rift localisation - as implied by the Wilson Cycle - modelling the effect of lithospheric heterogeneities on the long-term tectonic evolution of an extending plate in full 3D remains challenging. Recent progress in finite-element methods applied to computational tectonics along with the improved accessibility to high performance computers, now enable to switch from plane strain thermo-mechanical experiments to full 3D high-resolution experiments. Here we investigate the role of mechanical heterogeneities on rift opening, linkage and propagation during extension of a layered lithospheric systems with pTatin3d, a geodynamics modeling package utilising the material-point-method for tracking material composition, combined with a multigrid finite-element method to solve heterogeneous, incompressible visco-plastic Stokes problems. The initial model setup consists in a box of 1200 km horizontally by 250 km deep. It includes a 35 km layer of continental crust, underlaid by 85 km of sub-continental lithospheric mantle, and an asthenospheric mantle. Crust and mantle have visco-plastic rheologies with a pressure dependent yielding, which includes strain weakening, and a temperature, stress, strain-rate-dependent viscosity based on wet quartzite rheology for the crust, and wet olivine for the mantle. A constant extension rate is imposed on two opposite walls in the horizontal direction; the model' surface evolves freely; an isostatic boundary condition is imposed on the bottom wall. We explore a range of weak notches geometries, as well as the presence of random noise across a central region of the model. We compare the evolution of the geometry of the surface rift segments, their linkage and faults propagation during ongoing extension. These models allow us to assess the importance of mechanical heterogeneities for controlling passive margin geometries, and to precise the underlying physics governing continental breakup.

  14. Implications for karst hydrology from 3D geological modeling using the aquifer base gradient approach

    NASA Astrophysics Data System (ADS)

    Butscher, Christoph; Huggenberger, Peter

    2007-08-01

    SummaryWe use the gradient of the aquifer base to investigate the hydrology of mature, shallow karst systems. We first present a 3D geological model of the Gempen plateau (NW Switzerland) that reveals the geometry of aquifers and aquitards and their displacement at faults, then transfer the 3D geological model to a hydrological model. The transformation is based on a conceptual karst model approximating subsurface flow in mature, shallow karst systems to open surface flow on the top of the uppermost aquitard or aquifer base. The gradient of this surface is expected to mainly influence regional groundwater flow patterns. We use the hydrological model to delineate spring catchment areas. The discharge areas and corresponding catchment areas of the model are compared with the occurrence of springs in the study area and with hydraulic links confirmed by tracer tests. We also describe the way in which the hydrological model contributes to identifying flow processes. The proposed aquifer base gradient approach enhances vulnerability assessment in mature, shallow karst regions by (1) localizing catchment areas as a precondition of source protection strategies and (2) indicating dominant flow processes associated with individual springs.

  15. Bioprinting of 3D hydrogels.

    PubMed

    Stanton, M M; Samitier, J; Sánchez, S

    2015-07-14

    Three-dimensional (3D) bioprinting has recently emerged as an extension of 3D material printing, by using biocompatible or cellular components to build structures in an additive, layer-by-layer methodology for encapsulation and culture of cells. These 3D systems allow for cell culture in a suspension for formation of highly organized tissue or controlled spatial orientation of cell environments. The in vitro 3D cellular environments simulate the complexity of an in vivo environment and natural extracellular matrices (ECM). This paper will focus on bioprinting utilizing hydrogels as 3D scaffolds. Hydrogels are advantageous for cell culture as they are highly permeable to cell culture media, nutrients, and waste products generated during metabolic cell processes. They have the ability to be fabricated in customized shapes with various material properties with dimensions at the micron scale. 3D hydrogels are a reliable method for biocompatible 3D printing and have applications in tissue engineering, drug screening, and organ on a chip models. PMID:26066320

  16. 3D or not 3D - that is the question!

    Microsoft Academic Search

    Gregory P. Garvey

    2006-01-01

    Should an introduction to 3D computer graphics and animation be a part of a general core curriculum requirement for all design majors regardless their concentration, track or degree?At ACM-SIGGRAPH it is taken for granted that a working knowledge of 3D computer graphics is a valuable if not necessary part of a versatile skill set to prepare design graduates for future

  17. MONA 3D -- MOBILE NAVIGATION USING 3D CITY MODELS

    Microsoft Academic Search

    Volker Coors; Alexander Zipf

    Within this paper we present and discuss the goals and first results of a new collaborative pro- ject on mobile navigation using 3d city models call ed MoNa3D. In addition to the author's institutions (HFT Stuttgart and FH Mainz\\/University of Bonn) project partners include Navigon, Teleatlas, CPA Geoinformatik, Heidelberg Mobil and Bureau of Surveying Stuttgart. Here we investigate two main

  18. Reactivation mechanisms of heterogeneous, complex fault zones

    NASA Astrophysics Data System (ADS)

    Heesakkers, Vincent

    Fault reactivation occurs on a short-term cycle of tens to thousands of years between infrequent earthquakes, and on long-term cycles of fault inactivity for 106 -- 107 years. During long-term cycles, faults may heal and renew their strength. The objective of the present work is to study the mechanisms of fault reactivation after a long dormant period, when the pre-existing fault is not necessarily "weak". The study is conducted along the Pretorius fault, TauTona mine, South Africa. The deep gold mines in South Africa provide access to earthquake processes at focal depth, which was motivation for the NELSAM (Natural Earthquake Laboratory in South African Mines) project to develop an underground earthquake laboratory at ˜3.5 km depth within TauTona mine (Ch. 1). The present study is conducted within the NELSAM site that includes the 2.7 Ga Pretorius fault, which has been inactive for at least 2.0 Ga and is currently being reactivated due to nearby mining activity. I characterize the fault zone by 3D underground mapping within mining tunnels at 3.6 km depth (Ch. 2). The structural analysis is accompanied by fracture analysis from borehole image logs and micro-structural studies. I find that the Pretorius fault is structurally complex, with a 20-30 m wide zone of anastomosing, dominantly steep fault segments that contain a strong cohesive sintered cataclasite. Despite the size of the Pretorius fault, a few km long with ˜200m horizontal and 30-60 m vertical displacement, its complexity reflects the fault zone immaturity. The exposed rupture zone of the M2.2 of December 12, 2004, was mapped in detail at focal depth (Ch. 3). It reactivated three to four quasi-planar, non-parallel segments of the Pretorius fault, with characteristic generation of fresh fine grained rock powder along the contact of the quartzitic host rock and the cataclasite, indicating localization of slip during the event. To investigate the mechanism responsible for such localization, rock mechanics experiments were conducted on cataclasite and quartzite samples within the fault zone. The results show a mechanical contrast between the quartzite, that show significant strain hardening due to dilation of micro-cracks, and the weaker but more brittle cataclasite. A finite element analysis suggest that this mechanical heterogeneity effectively controls the localization of shear strain at the contact, similar to the observations of the M2.2 rupture and rock mechanics experiments. The stresses associated with the M2.2 rupture are calculated from in-situ stress measurements on borehole failures of three boreholes within 60 m from the exposed rupture (Ch. 4). The calculations, combined with the geometry of the rupture zone, suggest that slip during the M2.2 occurred under low shear stress. It is likely that stress interaction between the reactivated segments, and dynamic weakening due to gouge formation and lubrication allowed such slip. The earthquake energy balance of the event is estimated by combining field observations and stress measurements with the seismic signal. It appears that the fracture energy cannot be ignored and contributes for ˜ 1/3 to the total energy, similar to the frictional heat energy contribution. The unique setting provided an extraordinary data set of a single earthquake with field observations at focal depth, rock mechanics, rupture-associated stresses and seismic signal. The results describe reactivation processes in detail and contribute to the understanding of earthquake mechanisms.

  19. Oceanic transform faults: how and why do they form? (Invited)

    NASA Astrophysics Data System (ADS)

    Gerya, T.

    2013-12-01

    Oceanic transform faults at mid-ocean ridges are often considered to be the direct product of plate breakup process (cf. review by Gerya, 2012). In contrast, recent 3D thermomechanical numerical models suggest that transform faults are plate growth structures, which develop gradually on a timescale of few millions years (Gerya, 2010, 2013a,b). Four subsequent stages are predicted for the transition from rifting to spreading (Gerya, 2013b): (1) crustal rifting, (2) multiple spreading centers nucleation and propagation, (3) proto-transform faults initiation and rotation and (4) mature ridge-transform spreading. Geometry of the mature ridge-transform system is governed by geometrical requirements for simultaneous accretion and displacement of new plate material within two offset spreading centers connected by a sustaining rheologically weak transform fault. According to these requirements, the characteristic spreading-parallel orientation of oceanic transform faults is the only thermomechanically consistent steady state orientation. Comparison of modeling results with the Woodlark Basin suggests that the development of this incipient spreading region (Taylor et al., 2009) closely matches numerical predictions (Gerya, 2013b). Model reproduces well characteristic 'rounded' contours of the spreading centers as well as the presence of a remnant of the broken continental crustal bridge observed in the Woodlark basin. Similarly to the model, the Moresby (proto)transform terminates in the oceanic rather than in the continental crust. Transform margins and truncated tip of one spreading center present in the model are documented in nature. In addition, numerical experiments suggest that transform faults can develop gradually at mature linear mid-ocean ridges as the result of dynamical instability (Gerya, 2010). Boundary instability from asymmetric plate growth can spontaneously start in alternate directions along successive ridge sections; the resultant curved ridges become transform faults. Offsets along the transform faults change continuously with time by asymmetric plate growth and discontinuously by ridge jumps. The ridge instability is governed by rheological weakening of active fault structures. The instability is most efficient for slow to intermediate spreading rates, whereas ultraslow and (ultra)fast spreading rates tend to destabilize transform faults (Gerya, 2010; Püthe and Gerya, 2013) References Gerya, T. (2010) Dynamical instability produces transform faults at mid-ocean ridges. Science, 329, 1047-1050. Gerya, T. (2012) Origin and models of oceanic transform faults. Tectonophys., 522-523, 34-56 Gerya, T.V. (2013a) Three-dimensional thermomechanical modeling of oceanic spreading initiation and evolution. Phys. Earth Planet. Interiors, 214, 35-52. Gerya, T.V. (2013b) Initiation of transform faults at rifted continental margins: 3D petrological-thermomechanical modeling and comparison to the Woodlark Basin. Petrology, 21, 1-10. Püthe, C., Gerya, T.V. (2013) Dependence of mid-ocean ridge morphology on spreading rate in numerical 3-D models. Gondwana Res., DOI: http://dx.doi.org/10.1016/j.gr.2013.04.005 Taylor, B., Goodliffe, A., Martinez, F. (2009) Initiation of transform faults at rifted continental margins. Comptes Rendus Geosci., 341, 428-438.

  20. GRAPHICS PROGRAMMING SECTION D -JAVA 3D

    E-print Network

    Hill, Gary

    GRAPHICS PROGRAMMING SECTION D - JAVA 3D 1SECTION D - GRAPHICS 3-D........................................................................................... 2 30 Graphics 3D: Introduction to Java 3D........................................................................................ 78 ©Gary Hill September 2004 Java 3-D 1 of 13 #12;GRAPHICS PROGRAMMING SECTION D - GRAPHICS 3-D 30

  1. Lattice Boltzmann Method for 3-D Flows with Curved Boundary

    NASA Technical Reports Server (NTRS)

    Mei, Renwei; Shyy, Wei; Yu, Dazhi; Luo, Li-Shi

    2002-01-01

    In this work, we investigate two issues that are important to computational efficiency and reliability in fluid dynamics applications of the lattice, Boltzmann equation (LBE): (1) Computational stability and accuracy of different lattice Boltzmann models and (2) the treatment of the boundary conditions on curved solid boundaries and their 3-D implementations. Three athermal 3-D LBE models (D3QI5, D3Ql9, and D3Q27) are studied and compared in terms of efficiency, accuracy, and robustness. The boundary treatment recently developed by Filippova and Hanel and Met et al. in 2-D is extended to and implemented for 3-D. The convergence, stability, and computational efficiency of the 3-D LBE models with the boundary treatment for curved boundaries were tested in simulations of four 3-D flows: (1) Fully developed flows in a square duct, (2) flow in a 3-D lid-driven cavity, (3) fully developed flows in a circular pipe, and (4) a uniform flow over a sphere. We found that while the fifteen-velocity 3-D (D3Ql5) model is more prone to numerical instability and the D3Q27 is more computationally intensive, the 63Q19 model provides a balance between computational reliability and efficiency. Through numerical simulations, we demonstrated that the boundary treatment for 3-D arbitrary curved geometry has second-order accuracy and possesses satisfactory stability characteristics.

  2. 3D Mesh Generation in Geocomputing

    NASA Astrophysics Data System (ADS)

    Xing, Huilin; Yu, Wenhui; Zhang, Ji

    Mesh generation has been widely used in engineering computing, but seems to be relatively “new" for geoscience community. This paper firstly lists such relevant progresses of mesh generation for the engineering computing and then discusses the possibility for applying/extending them to geoscience computing (i.e. geocomputing). for geoscience, the available input data are normally a large quantity of point data in the 3D space rather than the defined shapes and dimensions with reasonable tolerances provided by the industrial designers, thus quite different from the engineering cases. To deal with such geoscience data, this paper briefly introduces the relevant progresses on geometrical modeling, hexahedral and tetrahedral shaped mesh generation, and then focuses on the applying and/or extending the related methods to generate all hexahedral/tetrahedral shaped meshes in 3D for geoscience purposes, which is described through the different practical application examples, such as the all-hexahedral shaped mesh generation for a fracture dominated reservoir system, the South Australia interacting fault system and the entire earth model without or with the simplified/practical plate boundaries; and all-tetrahedral shaped mesh generation for a multi-layer un- derground geological model, and visualizing and meshing with the microseismicity data recorded during a hydraulic stimulation process in a geothermal reservoir.

  3. Symplectic Geometry Metric geometry

    E-print Network

    Wolpert, Scott A.

    surfaces, metric space geometry, as well as the analytic/algebraic geometry of curvature, characteristicBasics Symplectic Geometry Curvature Metric geometry Random geodesics Weil-Petersson sampler;Basics Symplectic Geometry Curvature Metric geometry Random geodesics Table of contents 1 Introduction

  4. Multicomponent 3-D characterization of a coalbed methane reservoir

    SciTech Connect

    Shuck, E.L. [Advance Geophysical Corp., Englewood, CO (United States)] [Advance Geophysical Corp., Englewood, CO (United States); Davis, T.L.; Benson, R.D. [Colorado School of Mines, Golden, CO (United States). Geophysics Dept.] [Colorado School of Mines, Golden, CO (United States). Geophysics Dept.

    1996-03-01

    Methane is produced from fractured coalbed reservoirs at Cedar Hill Field in the San Juan Basin. Fracturing and local stress are critical to production because of the absence of matrix permeability in the coals. Knowledge of the direction of open fractures, the degree of fracturing, reservoir pressure, and compartmentalization is required to understand the flow of fluids through the reservoir. A multicomponent 3-D seismic survey was acquired to aid in coalbed methane reservoir characterization. Coalbed reservoir heterogeneities, including isolated pressure cells, zones of increased fracture density, and variable fracture directions, have been interpreted through the analysis of the multicomponent data and integration with petrophysical and reservoir engineering studies. Strike-slip faults, which compartmentalize the reservoir, have been identified by structural interpretation of the 3-D P-wave seismic data. These faults form boundaries for pressure cells that have been identified by P-wave reflection amplitude anomalies.

  5. Accepting the T3D

    SciTech Connect

    Rich, D.O.; Pope, S.C.; DeLapp, J.G.

    1994-10-01

    In April, a 128 PE Cray T3D was installed at Los Alamos National Laboratory`s Advanced Computing Laboratory as part of the DOE`s High-Performance Parallel Processor Program (H4P). In conjunction with CRI, the authors implemented a 30 day acceptance test. The test was constructed in part to help them understand the strengths and weaknesses of the T3D. In this paper, they briefly describe the H4P and its goals. They discuss the design and implementation of the T3D acceptance test and detail issues that arose during the test. They conclude with a set of system requirements that must be addressed as the T3D system evolves.

  6. Map Rainfall in 3D

    NSDL National Science Digital Library

    William Montgomery

    William Montgomery, New Jersey City University Summary This comprehensive activity introduces students to onscreen digitizing (OSD); automated mapping (Add XY Event Theme); table joins; 3D models; and automated ...

  7. Combinatorial 3D Mechanical Metamaterials

    NASA Astrophysics Data System (ADS)

    Coulais, Corentin; Teomy, Eial; de Reus, Koen; Shokef, Yair; van Hecke, Martin

    2015-03-01

    We present a class of elastic structures which exhibit 3D-folding motion. Our structures consist of cubic lattices of anisotropic unit cells that can be tiled in a complex combinatorial fashion. We design and 3d-print this complex ordered mechanism, in which we combine elastic hinges and defects to tailor the mechanics of the material. Finally, we use this large design space to encode smart functionalities such as surface patterning and multistability.

  8. Exploring 3D Printing Alternatives

    Microsoft Academic Search

    Sandeep Singh

    \\u000a Throughout most of this book, you have spent a majority of your time learning about Shapeways and SketchUp. Both work well\\u000a together when designing and developing models for 3D printing. The ease of using SketchUp and the ability to effortlessly\\u000a upload and 3D print models are amazing. In this chapter, we switch gears and introduce a few other tools and

  9. 3D Topographic Map Simulation

    NSDL National Science Digital Library

    This interactive simulation illustrates how topographic maps are created and used to depict landforms and changes in elevation. Students can sculpt mountains and valleys using a 3-D model and see the changes to the corresponding topographic map, or make alterations to the map and see how the 3-D terrain model changes. The display can be tilted, rotated, or enlarged to view changes to the map and/or terrain model.

  10. Fundamentals of 3D halftoning

    Microsoft Academic Search

    Qun Lou; Peter Stucki

    3D halftoning is a new technique that allows the approximation of digital volumetric objects of varying material density e.g.\\u000a porous media for example, by an ensemble of binary material volume elements called vels. In theory, 3D halftoning is basically\\u000a an extension of the well known 2D halftoning process, as widely used in binary printing applications. In practice, however,\\u000a the development

  11. 3-D seismic survey of the eastern Nankai subduction zone: from field program to prestack depth imaging

    NASA Astrophysics Data System (ADS)

    Noble, M.; Martin, V.; Pascal, G.; Lallemand, S.; Thierry, P.

    2003-04-01

    In the eastern part of the Nankai accretionnary complex, the deformation is distributed over a wide area, as consequence of the vicinity of the nearby collision between the Izu-Bonin ridge and central Japan. Deformation occurs both in the down going plate (Zenisu Ridge compressive system) and the upper plate (active faults Tokai, Kodaiba and Enshu in the fore arc region). Previous 2-D seismic and bathymetric surveys in this area strongly suggest that this accretionnary complex is a true three dimensional structure and should be treated as such. The Ifremer research vessel N/O Nadir acquired multichannel seismic data designed to image the 3-D structural geometry of this subduction zone. The N/O Nadir digital multichannel seismic field system was composed of a 360-trace, 12.5 m active group, digital streamer equipped with 16 compasses and a tail buoy with R-GPS. The 3-D survey grid consists of fifty one , 45 km long parallel lines, each separated by 100 m. In addition 20 extra in-fill lines were shot during the 42 days cruise. The data were acquired using a 12-air-gun array with a total volume of 2650 cubic inchs. Shots were fired at 50m intervals and 12 s of data were recorded. We outline the data acquisition program, including navigation critical to successful imaging, and the seismic processing methodology. The resulting 3-D seismic data were migrated (prestack depth migration) both as independent lines and as a 3-D volume. The ability to view the 3-D data volume in both section and plan view offers significant interpretational advantages. To illustrate these improvements, we present images of deep complex structures, and also a detailed imaging of a BSR in the near subsurface.

  12. Static 3D image space

    NASA Astrophysics Data System (ADS)

    Koudsi, Badia; Sluss, Jim J., Jr.

    2010-02-01

    As three-dimensional (3D) techniques continue to evolve from their humble beginnings-nineteenth century stereo photographs and twentieth century movies and holographs, the urgency for advancement in 3D display is escalating, as the need for widespread application in medical imaging, baggage scanning, gaming, television and movie display, and military strategizing increases. The most recent 3D developments center upon volumetric display, which generate 3D images within actual 3D space. More specifically, CSpace volumetric display generates a truly natural 3D image consisting of perceived width, height, and depth within the confines of physical space. Wireframe graphics enable viewers a 360-degree display without the use of additional visual aids. In this paper, research detailing the selection and testing of several rare earth, single-doped, fluoride crystals, namely 1%Er: NYF4, 2%Er: NYF4, 3%Er: NYF4 , 2%Er:KY3F10, and 2%Er:YLF, is introduced. These materials are the basis for CSpace display in a two-step twofrequency up-Conversion process. Significant determinants were tested and identified to aid in the selection of a suitable medium. Results show that 2%Er: NYF4 demonstrates good optical emitted power. Its superior level of brightness makes it the most suitable candidate for CSpace display. Testing also proved 2%Er: KY3F10 crystal might be a viable medium.

  13. Natural 3D content on glasses-free light-field 3D cinema

    NASA Astrophysics Data System (ADS)

    Balogh, Tibor; Nagy, Zsolt; Kovács, Péter Tamás.; Adhikarla, Vamsi K.

    2013-03-01

    This paper presents a complete framework for capturing, processing and displaying the free viewpoint video on a large scale immersive light-field display. We present a combined hardware-software solution to visualize free viewpoint 3D video on a cinema-sized screen. The new glasses-free 3D projection technology can support larger audience than the existing autostereoscopic displays. We introduce and describe our new display system including optical and mechanical design considerations, the capturing system and render cluster for producing the 3D content, and the various software modules driving the system. The indigenous display is first of its kind, equipped with front-projection light-field HoloVizio technology, controlling up to 63 MP. It has all the advantages of previous light-field displays and in addition, allows a more flexible arrangement with a larger screen size, matching cinema or meeting room geometries, yet simpler to set-up. The software system makes it possible to show 3D applications in real-time, besides the natural content captured from dense camera arrangements as well as from sparse cameras covering a wider baseline. Our software system on the GPU accelerated render cluster, can also visualize pre-recorded Multi-view Video plus Depth (MVD4) videos on this light-field glasses-free cinema system, interpolating and extrapolating missing views.

  14. METHODS OF PARALLEL VOXEL MANIPULATION FOR 3D DIGITAL PRINTING

    Microsoft Academic Search

    Jonathan Hiller; Hod Lipson

    A novel digital printing concept is explored for desktop fabrication of multi- material objects with arbitrary 3D geometry. Digital objects are composed of many discrete, self-aligning voxels instead of continuous (analog) deposition techniques. Overall accuracy is determined by the individual voxels instead of the printer, and digital properties such as perfect replication and error correction are physically meaningful. The key

  15. Stereo-vision-based 3D modeling of space structures

    Microsoft Academic Search

    Stephen Se; Piotr Jasiobedzki; Richard Wildes

    2007-01-01

    Servicing satellites in space requires accurate and reliable 3D information. Such information can be used to create virtual models of space structures for inspection (geometry, surface flaws, and deployment of appendages), estimation of relative position and orientation of a target spacecraft during autonomous docking or satellite capture, replacement of serviceable modules, detection of unexpected objects and collisions. Existing space vision

  16. 3D anisotropic mesh adaptation by mesh modification

    Microsoft Academic Search

    Xiangrong Li; Mark S. Shephard; Mark W. Beall

    2005-01-01

    This paper describes an effective anisotropic mesh adaptation procedure for general 3D geometries using mesh modification operations. The procedure consists of four interacted high level components: refinement, coarsening, projecting boundary vertices and shape correction. All components are governed by an anisotropic mesh metric field that represents the desired element size and shape distribution. The paper presents the application for the

  17. Application of a 3D Hydrodynamic Model in Curved Channels

    Microsoft Academic Search

    J. A. McCorquodale; Jian Ye; R. M. Barron

    1998-01-01

    A 3D hydrodynamic model was developed to simulate turbulent flows with a free surface. The model includes some recently developed CFD (Computational Fluid Dynamics) techniques and treatments, e.g. (1) a curvilinear coordinate system in the x-y plane to model irregular natural geometry. (2) a - coordinate in z- direction to represent the unknown free surface, and irregular bed topography; (3)

  18. Silhouette and stereo fusion for 3D object modeling

    Microsoft Academic Search

    Carlos Hernández Esteban; Francis Schmitt

    2004-01-01

    Abstract: In this paper we present a new approach to high quality 3Dobject reconstruction. Starting from a calibrated sequenceof color images, the algorithm is able to reconstruct boththe 3D geometry and the texture. The core of the method isbased on a deformable model, which defines the frameworkwhere texture and silhouette information can be fused. Thisis achieved by defining two external

  19. 3D geological modelling using laser and hyperspectral data

    Microsoft Academic Search

    Juan I. Nieto; Sildomar T. Monteiro; Diego Viejo

    2010-01-01

    This paper presents a ground based system for mapping the geology and the geometry of the environment remotely. The main objective of this work is to develop a framework for a mobile robotic platform that can build 3D geological maps. We investigate classification and registration algorithms that can work without any manual intervention. The system capabilities are demonstrated with data

  20. Modeling the Properties of 3D Woven Composites

    SciTech Connect

    Cox, B.N.

    1995-10-01

    An extensive study has been completed of the internal geometry, the mechanisms of failure, and the micromechanics of local failure events in graphite/epoxy composites with three dimensional (3D) woven reinforcement. This work has led to the development of models for predicting elastic constants, strength, notch sensitivity, and fatigue life. A summary is presented here.

  1. JCISE Application Paper Crowdsourcing Canonical Views of 3D Models

    E-print Network

    Martin, Ralph R.

    made it has generally solved special cases (eg. 2.5D geometry) rather than providing generic solutionsJCISE Application Paper Crowdsourcing Canonical Views of 3D Models P.Jagadeesan*, J.Wenzel# , J the initial results of using Crowdsourcing to determine the "best" canonical, or characteristic, views

  2. Automatic Reconstruction of 3D CAD Models from Digital Scans

    Microsoft Academic Search

    Fausto Bernardini; Chandrajit L. Bajaj; Jindong Chen; Daniel Schikore

    1999-01-01

    We present an approach for the reconstruction andapproximation of 3D CAD models from an unorganizedcollection of points. Applications include rapidreverse engineering of existing objects for use in asynthetic computer environment, including computeraided design and manufacturing. Our reconstructionapproach is flexible enough to permit interpolation ofboth smooth surfaces and sharp features, while placingfew restrictions on the geometry or topology ofthe object.Our algorithm

  3. High resolution earthquake source mechanisms in a subduction zone: 3-D waveform simulations of aftershocks from the 2010 Mw 8.8 Chile rupture

    NASA Astrophysics Data System (ADS)

    Hicks, Stephen; Rietbrock, Andreas

    2015-04-01

    The earthquake rupture process is extremely heterogeneous. For subduction zone earthquakes in particular, it is vital to understand how structural variations in the overriding plate and downgoing slab may control slip style. The large-scale 3-D geometry of subduction plate boundaries is rapidly becoming well understood (e.g. Hayes et al., 2012); however, the nature of slip style along any finer-scale structures remains elusive. Regional earthquake moment tensor (RMT) inversion can shed light on faulting mechanisms. However, many traditional regional moment tensor inversions use simplified (1-D) Earth models (e.g. Agurto et al., 2012; Hayes et al., 2013) that only use the lowest frequency parts of the waveform, which may mask source complexity. As a result, we may have to take care when making small-scale interpretations about the causative fault and its slip style. This situation is compounded further by strong lateral variations in subsurface geology, as well as poor station coverage for recording offshore subduction earthquakes. A formal assessment of the resolving capability of RMT inversions in subduction zones is challenging and the application of 3-D waveform simulation techniques in highly heterogeneous media is needed. We generate 3-D waveform simulations of aftershocks from a large earthquake that struck Chile in 2010. The Mw 8.8 Maule earthquake is the sixth largest earthquake ever recorded. Following the earthquake, there was an international deployment of seismic stations in the rupture area, making this one of the best observed aftershock sequences to date. We therefore have a unique opportunity to compare recorded waveforms with simulated waveforms for many earthquakes, shedding light on the effect of 3-D heterogeneity on source imaging. We perform forward simulations using the spectral element wave propagation code, SPEFEM3D (e.g. Komatitsch et al., 2010) for a set of moderate-sized aftershocks (Mw 4.0-5.5). A detailed knowledge of velocity structure for the region as well as robust earthquake locations (Hicks et al., 2014) ensure that our 3-D simulations are robust. We perform regional moment tensor inversion using the ISOLA software package (Sokos & Zahradnik, 2008), incorporating 3-D Green's functions from the forward simulations. With this approach, we are able to test the resolving capability of traditional 1-D strategies. We find that focal mechanism dip and source depth are the parameters that are most biased parameters in 1-D RMT inversions, particularly for events that are located far offshore. We also describe and interpret observations of normal faulting earthquakes along the plate interface. This finding may have important implications for post-seismic fluid release.

  4. Finite-Source Inversion for the 2004 Parkfield Earthquake using 3D Velocity Model Green's Functions

    NASA Astrophysics Data System (ADS)

    Kim, A.; Dreger, D.; Larsen, S.

    2008-12-01

    We determine finite fault models of the 2004 Parkfield earthquake using 3D Green's functions. Because of the dense station coverage and detailed 3D velocity structure model in this region, this earthquake provides an excellent opportunity to examine how the 3D velocity structure affects the finite fault inverse solutions. Various studies (e.g. Michaels and Eberhart-Phillips, 1991; Thurber et al., 2006) indicate that there is a pronounced velocity contrast across the San Andreas Fault along the Parkfield segment. Also the fault zone at Parkfield is wide as evidenced by mapped surface faults and where surface slip and creep occurred in the 1966 and the 2004 Parkfield earthquakes. For high resolution images of the rupture process"Ait is necessary to include the accurate 3D velocity structure for the finite source inversion. Liu and Aurchuleta (2004) performed finite fault inversions using both 1D and 3D Green's functions for 1989 Loma Prieta earthquake using the same source paramerization and data but different Green's functions and found that the models were quite different. This indicates that the choice of the velocity model significantly affects the waveform modeling at near-fault stations. In this study, we used the P-wave velocity model developed by Thurber et al (2006) to construct the 3D Green's functions. P-wave speeds are converted to S-wave speeds and density using by the empirical relationships of Brocher (2005). Using a finite difference method, E3D (Larsen and Schultz, 1995), we computed the 3D Green's functions numerically by inserting body forces at each station. Using reciprocity, these Green's functions are recombined to represent the ground motion at each station due to the slip on the fault plane. First we modeled the waveforms of small earthquakes to validate the 3D velocity model and the reciprocity of the Green"fs function. In the numerical tests we found that the 3D velocity model predicted the individual phases well at frequencies lower than 0.25 Hz but that the velocity model is fast at stations located very close to the fault. In this near-fault zone the model also underpredicts the amplitudes. This implies the need to include an additional low velocity zone in the fault zone to fit the data. For the finite fault modeling we use the same stations as in our previous study (Kim and Dreger 2008), and compare the results to investigate the effect of 3D Green's functions on kinematic source inversions. References: Brocher, T. M., (2005), Empirical relations between elastic wavespeeds and density in the Earth's crust, Bull. Seism. Soc. Am., 95, No. 6, 2081-2092. Eberhart-Phillips, D., and A.J. Michael, (1993), Three-dimensional velocity structure and seismicity in the Parkfield region, central California, J. Geophys. Res., 98, 15,737-15,758. Kim A., D. S. Dreger (2008), Rupture process of the 2004 Parkfield earthquake from near-fault seismic waveform and geodetic records, J. Geophys. Res., 113, B07308. Thurber, C., H. Zhang, F. Waldhauser, J. Hardebeck, A. Michaels, and D. Eberhart-Phillips (2006), Three- dimensional compressional wavespeed model, earthquake relocations, and focal mechanisms for the Parkfield, California, region, Bull. Seism. Soc. Am., 96, S38-S49. Larsen, S., and C. A. Schultz (1995), ELAS3D: 2D/3D elastic finite-difference wave propagation code, Technical Report No. UCRL-MA-121792, 19pp. Liu, P., and R. J. Archuleta (2004), A new nonlinear finite fault inversion with three-dimensional Green's functions: Application to the 1989 Loma Prieta, California, earthquake, J. Geophys. Res., 109, B02318.

  5. Estimating Hydraulic Conductivities in a Fractured Shale Formation from Pressure Pulse Testing and 3d Modeling

    NASA Astrophysics Data System (ADS)

    Courbet, C.; DICK, P.; Lefevre, M.; Wittebroodt, C.; Matray, J.; Barnichon, J.

    2013-12-01

    In the framework of its research on the deep disposal of radioactive waste in shale formations, the French Institute for Radiological Protection and Nuclear Safety (IRSN) has developed a large array of in situ programs concerning the confining properties of shales in their underground research laboratory at Tournemire (SW France). One of its aims is to evaluate the occurrence and processes controlling radionuclide migration through the host rock, from the disposal system to the biosphere. Past research programs carried out at Tournemire covered mechanical, hydro-mechanical and physico-chemical properties of the Tournemire shale as well as water chemistry and long-term behaviour of the host rock. Studies show that fluid circulations in the undisturbed matrix are very slow (hydraulic conductivity of 10-14 to 10-15 m.s-1). However, recent work related to the occurrence of small scale fractures and clay-rich fault gouges indicate that fluid circulations may have been significantly modified in the vicinity of such features. To assess the transport properties associated with such faults, IRSN designed a series of in situ and laboratory experiments to evaluate the contribution of both diffusive and advective process on water and solute flux through a clay-rich fault zone (fault core and damaged zone) and in an undisturbed shale formation. As part of these studies, Modular Mini-Packer System (MMPS) hydraulic testing was conducted in multiple boreholes to characterize hydraulic conductivities within the formation. Pressure data collected during the hydraulic tests were analyzed using the nSIGHTS (n-dimensional Statistical Inverse Graphical Hydraulic Test Simulator) code to estimate hydraulic conductivity and formation pressures of the tested intervals. Preliminary results indicate hydraulic conductivities of 5.10-12 m.s-1 in the fault core and damaged zone and 10-14 m.s-1 in the adjacent undisturbed shale. Furthermore, when compared with neutron porosity data from borehole logging, porosity varies by a factor of 2.5 whilst hydraulic conductivity varies by 2 to 3 orders of magnitude. In addition, a 3D numerical reconstruction of the internal structure of the fault zone inferred from borehole imagery has been built to estimate the permeability tensor variations. First results indicate that hydraulic conductivity values calculated for this structure are 2 to 3 orders of magnitude above those measured in situ. Such high values are due to the imaging method that only takes in to account open fractures of simple geometry (sine waves). Even though improvements are needed to handle more complex geometry, outcomes are promising as the fault damaged zone clearly appears as the highest permeability zone, where stress analysis show that the actual stress state may favor tensile reopening of fractures. Using shale samples cored from the different internal structures of the fault zone, we aim now to characterize the advection and diffusion using laboratory petrophysical tests combined with radial and through-diffusion experiments.

  6. 3-D threat image projection

    NASA Astrophysics Data System (ADS)

    Yildiz, Yesna O.; Abraham, Douglas Q.; Agaian, Sos; Panetta, Karen

    2008-02-01

    Automated Explosive Detection Systems utilizing Computed Tomography perform a series X-ray scans of passenger bags being checked in at the airport, and produce various 2-D projection images and 3-D volumetric images of the bag. The determination as to whether the passenger bag contains an explosive and needs to be searched manually is performed through trained Transportation Security Administration screeners following an approved protocol. In order to keep the screeners vigilant with regards to screening quality, the Transportation Security Administration has mandated the use of Threat Image Projection on 2-D projection X-ray screening equipment used at all US airports. These algorithms insert visual artificial threats into images of the normal passenger bags in order to test the screeners with regards to their screening efficiency and their screening quality at determining threats. This technology for 2-D X-ray system is proven and is widespread amongst multiple manufacturers of X-ray projection systems. Until now, Threat Image Projection has been unsuccessful at being introduced into 3-D Automated Explosive Detection Systems for numerous reasons. The failure of these prior attempts are mainly due to imaging queues that the screeners pickup on, and therefore make it easy for the screeners to discern the presence of the threat image and thus defeating the intended purpose. This paper presents a novel approach for 3-D Threat Image Projection for 3-D Automated Explosive Detection Systems. The method presented here is a projection based approach where both the threat object and the bag remain in projection sinogram space. Novel approaches have been developed for projection based object segmentation, projection based streak reduction used for threat object isolation along with scan orientation independence and projection based streak generation for an overall realistic 3-D image. The algorithms are prototyped in MatLab and C++ and demonstrate non discernible 3-D threat image insertion into various luggage, and non discernable streak patterns for 3-D images when compared to actual scanned images.

  7. HYFRAC3D. Finite Element Code for 3D-Hydraulic Fracture Propagation Equations (Mult-Layer)

    Microsoft Academic Search

    S. H. Advani; J. K. Lee; T. S. Lee

    1988-01-01

    HYFRAC3D is a finite element program for simulation of three-dimensional fracture geometries with a two-dimensional planar solution. The model predicts the height, width and winglength over time for a hydraulic fracture propagating in a multi-layered system of rock with variable fluid flow and rock mechanics properties.

  8. HYFRAC3D. Finite Element Code For 3D-Hydraulic Fracture Propagation Equations (Mult-Layer)

    Microsoft Academic Search

    S. H. Advani; J. K. Lee; T. S. Lee

    1988-01-01

    HYFRAC3D is a finite element program for simulation of three-dimensional fracture geometries with a two-dimensional planar solution. The model predicts the height, width and winglength over time for a hydraulic fracture propagating in a multi-layered system of rock with variable fluid flow and rock mechanics properties.

  9. 3D Ultrasonic Wave Simulations for Structural Health Monitoring

    NASA Technical Reports Server (NTRS)

    Campbell, Leckey Cara A/; Miler, Corey A.; Hinders, Mark K.

    2011-01-01

    Structural health monitoring (SHM) for the detection of damage in aerospace materials is an important area of research at NASA. Ultrasonic guided Lamb waves are a promising SHM damage detection technique since the waves can propagate long distances. For complicated flaw geometries experimental signals can be difficult to interpret. High performance computing can now handle full 3-dimensional (3D) simulations of elastic wave propagation in materials. We have developed and implemented parallel 3D elastodynamic finite integration technique (3D EFIT) code to investigate ultrasound scattering from flaws in materials. EFIT results have been compared to experimental data and the simulations provide unique insight into details of the wave behavior. This type of insight is useful for developing optimized experimental SHM techniques. 3D EFIT can also be expanded to model wave propagation and scattering in anisotropic composite materials.

  10. Coseismic deformation due to the 2011 Tohoku, Japan, earthquake: influence of 3-D elastic heterogeneity

    NASA Astrophysics Data System (ADS)

    Hashima, A.; Becker, T. W.; Freed, A. M.; Sato, H.; Okaya, D. A.; Suito, H.; Hatanaka, Y.; Matsubara, M.; Takeda, T.; Ishiyama, T.; Iwasaki, T.

    2014-12-01

    The 2011 M9 Tohoku earthquake ruptured a fault area with length and width of ~500 km and ~200 km, respectively, and elastically deformed broad lithospheric and mantle regions. In order to evaluate the influence of the Tohoku earthquake on lithospheric stresses throughout Japan, an accurate accounting of coseismic slip is very important as the initial condition. We investigate the effects of heterogeneous elastic moduli under Japan on the inversion for coseismic slip, utilizing the land-based Japan GPS network as well as seafloor geodetic constraints near the trench. For this purpose, we construct a 3-D finite element model (FEM) to generate Green's functions that allows considering the influence of complex slab geometry as well as heterogeneities in elastic structure. Our FEM incorporates the Pacific and Philippine sea slabs by interpolating seismicity for the Tohoku region and the Nankai trough, as well as the Kuril, Ryukyu and Izu-Bonin arcs. As fault source geometry, we consider not only the Pacific but also the Phillipine sea slab, with initial results suggesting that slip occurring beyond the triple junction is ~1 m. As for elastic heterogeneity, we investigated the effect of the crust-mantle stratification, the contrast of oceanic and continental crust, and the effects of slabs. Results indicate that crust-mantle stratification has to be considered to obtain an appropriate coseismic slip distribution; heterogeneous models show smaller maximum slip and a wider distribution compared to homogeneous structure. This confirms some earlier work, but is in contrast to some recent suggestions. The effect of the ocean-continent contrast and deep slab heterogeneity appear negligible for co-seismic inversions.

  11. YouDash3D: exploring stereoscopic 3D gaming for 3D movie theaters

    NASA Astrophysics Data System (ADS)

    Schild, Jonas; Seele, Sven; Masuch, Maic

    2012-03-01

    Along with the success of the digitally revived stereoscopic cinema, events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and 3D movie theater gaming.

  12. 3D modelling in salt tectonic context: the Crocodile minibasin in Sivas (Turkey)

    NASA Astrophysics Data System (ADS)

    Collon, Pauline; Pichat, Alexandre; Kergaravat, Charlie; Botella, Arnaud; Caumon, Guillaume; Favreau, Océane; Fuss, Gaétan; Godefroy, Gabriel; Lerat, Marine; Mazuyer, Antoine; Parquer, Marion; Charreau, Julien; Callot, Jean-Paul; Ringenbach, Jean-Claude

    2015-04-01

    Impermeable, with a low density and acting as a viscous fluid at the geological time scale, salt plays a unique tectonic role favouring hydrocarbon trap formations. Halokinetic structures are various and difficult to image with classic seismic techniques. Thus, outcrop analogues are precious and sought after. Since the re-interpretation in September 2011 of its evaporite deposits, the Oligo-Miocene basin of Sivas (Turkey) is a new choice analogue for the study of salt tectonic with outstanding outcrops reflecting the variety of salt related structures: minibasins, diapirs, welds... While studying these structures requires an important field work, building 3D models becomes an interesting way to better help understanding the three-dimensional organisation and to further perform numerical simulations (e.g., restoration, potential field measurement campaign simulation). The complex geometries observed in salt tectonic context make these 3D geological models particularly challenging to build, especially when only outcrops data are available. We focus on the Crocodile minibasin (Sivas) and present a modelling strategy using a subtle combination of recently developed techniques. Available data are: a Digital Elevation Model, satellite images and associated interpreted bedding traces on topography, orientation measurements of the strata and a conceptual interpretation. Located on an ancient salt extrusion, this minibasin is filled with lacustrine and sabkha sediments. It is interpreted with a closed synclinal structure on North. On its southern part, a central diapir has risen up, separating two tightened synclinals. The salt surface is modelled first as a triangulated surface using a classical explicit surface patch construction method and a manual post-process mesh improvement. Then, the minibasin sediments are modelled with an implicit approach that considers interfaces as equipotentials of a 3D scalar field. This requires to build a volumetric mesh conformable to the salt surface to consistently disconnect both minibasin parts. This step is performed thanks to a local simplification of the salt surface that consists in replacing pinched parts by an equivalent fault/weld surface. The 3D scalar field is then computed with a Discrete Smooth Interpolation constrained by several information. Those information are weighted consistently with their relative uncertainty. Control points impose locally the scalar field value. They are set on interpreted bedding traces and on a surface located at 5m from the external salt surface boundary to account for the tangency of the sediment deposits in conformable parts of the minibasin. They are completed by constraints on the scalar field gradient orientation using dip measurements and a constant gradient constraint. The result highlights the remarkable geometry of this salt-tectonic related structure and underlines the usefulness of new modelling methods to ease a more automated generation of such tectonic features.

  13. Spectral element modeling of earthquake nucleation and spontaneous rupture on rate and state faults

    NASA Astrophysics Data System (ADS)

    Kaneko, Y.; Lapusta, N.; Ampuero, J.

    2006-12-01

    Nucleation and spontaneous dynamic propagation of earthquakes on rate and state faults have been successfully modeled in the framework of boundary integral methods (BIM) (e.g., Rice and Ben-Zion, 1996; Lapusta et al., 2000). However, these studies have been mostly restricted to planar faults embedded into a uniform elastic space or half-space, due to the nature of BIM. At the same time, observations show complicated crustal structures such as layers of bulk materials, fault damage zones, and non-planar fault geometries. It is important to include those factors into earthquake models, combining them with laboratory- derived constitutive fault relations such as rate and state friction. In this work, we use 3-D spectral element method (SEM) to model earthquake nucleation and propagation of spontaneous rupture on a vertical strike-slip fault governed by rate and state friction. SEM can incorporate variable bulk properties and more complex fault geometries, but it has been used so far mostly with slip- weakening fault friction to simulate a single earthquake episode (Ampuero, Ph.D. thesis, 2002). To assess the accuracy of numerical results in the absence of an analytical solution, we have created a simple test problem and used it to compare 2-D SEM results with the ones obtained by 2-D BIM in its spectral formulation. We find that SEM and BIM give virtually indistinguishable solutions to the nucleation and spontaneous rupture propagation when the node spacing is small enough. We will report on the convergence studies we have done in the context of different choices for the update of the state variable, smooth vs. abrupt initial conditions, and different state variable friction laws. We will also present our current work on using 3-D SEM simulations of single events, on both slip-weakening and rate-and-state faults, to understand how much can be learned from the near-field seismic records in terms of the history of slip or slip rate on the fault. Our ultimate goal is to develop a SEM framework for simulating long-term deformation histories, in terms of sequences of earthquakes and combination of seismic and aseismic sliding.

  14. Speaking Volumes About 3-D

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In 1999, Genex submitted a proposal to Stennis Space Center for a volumetric 3-D display technique that would provide multiple users with a 360-degree perspective to simultaneously view and analyze 3-D data. The futuristic capabilities of the VolumeViewer(R) have offered tremendous benefits to commercial users in the fields of medicine and surgery, air traffic control, pilot training and education, computer-aided design/computer-aided manufacturing, and military/battlefield management. The technology has also helped NASA to better analyze and assess the various data collected by its satellite and spacecraft sensors. Genex capitalized on its success with Stennis by introducing two separate products to the commercial market that incorporate key elements of the 3-D display technology designed under an SBIR contract. The company Rainbow 3D(R) imaging camera is a novel, three-dimensional surface profile measurement system that can obtain a full-frame 3-D image in less than 1 second. The third product is the 360-degree OmniEye(R) video system. Ideal for intrusion detection, surveillance, and situation management, this unique camera system offers a continuous, panoramic view of a scene in real time.

  15. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITHOUT TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity