Download or read book Testing Kinematic Fault slip Models in the Eastern California Shear Zone Walker Lane Belt written by Rachelle Marie Warren and published by . This book was released on 2014 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fault Slip Transfer in the Eastern California Shear Zone Walker Lane Belt written by Jeffrey Lee and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This field trip guide focuses on the kinematics of faulting across an extensional relay zone from the northern Eastern California Shear Zone into the southern Walker Lane Belt. It reviews evidence for active dextral slip along the NW-striking White Mountains fault zone, normal slip along the NE-striking Queen Valley fault, and sinistral slip along the ENE-striking Coaldale fault, and the kinematics of fault slip transfer from one fault system to another.
Download or read book New Insights Into Strain Accumulation and Release in the Central and Northern Walker Lane Pacific North American Plate Boundary California and Nevada USA written by Jayne Margret Bormann and published by . This book was released on 2013 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Walker Lane is a 100 km-wide distributed zone of complex transtensional faulting that flanks the eastern margin of the Sierra Nevada. Up to 25% of the total Pacific-North American relative right-lateral plate boundary deformation is accommodated east of the Sierra Nevada, primarily in the Walker Lane. The results of three studies in the Central and Northern Walker Lane offer new insights into how constantly accumulating plate boundary shear strain is released on faults in the Walker Lane and regional earthquake hazards. This research is based on the collection and analysis of new of geologic and geodetic datasets. Two studies are located in the Central Walker Lane, where plate boundary deformation is accommodated on northwest trending right-lateral faults, east-northeast trending left-lateral faults, and north trending normal faults. In this region, a prominent set of left-stepping, en-echelon, normal fault-bounded basins between Walker Lake and Lake Tahoe fill a gap in Walker Lane strike slip faults. Determining how these basins accommodate shear strain is a primary goal of this research. Paleoseismic and neotectonic observations from the Wassuk Range fault zone in the Walker Lake basin record evidence for at least 3 Holocene surface rupturing earthquakes and Holocene/late Pleistocene vertical slip rates between 0.4-0.7 mm/yr on the normal fault, but record no evidence of right-lateral slip along the rangefront fault. A complementary study presents new GPS velocity data that measures present-day deformation across the Central Walker Lane and infers fault slip and block rotation rates using an elastic block model. The model results show a clear partitioning between distinct zones of strain accommodation characterized by (1) right-lateral translation of blocks on northwest trending faults, (2) left-lateral slip and clockwise block rotations between east and northeast trending faults, and (3) right-lateral oblique normal slip with minor clockwise block rotations on north trending faults. Block model results show that a component of right-lateral slip in the normal-fault bounded basins is required to adequately fit the GPS data. New GPS data from the Northern Walker Lane constrains present-day slip rates on the Mohawk Valley, Grizzly Valley, and Honey Lake fault zones. Block model results predict right-lateral slip rates of 2.2 ± 0.2 mm/yr for the Mohawk Valley fault and 1.1 ± 0.4 mm/yr for the Honey Lake fault. The GPS data do not require slip on the Grizzly Valley fault, although right-lateral slip rates up to 1.2 mm/yr are allowed without increasing the block model misfit. The present-day distribution of slip between the Honey Lake and Mohawk Valley faults is opposite that predicted by latest Quaternary and Holocene geologic slip rate estimates. A temporally variable Wallace-type strain release model that includes 104-year timescale variations in fault slip rate could reconcile both datasets.
Download or read book Geophysical Characterization of Transtensional Fault Systems in the Eastern California Shear Zone Walker Lane Belt written by Matthew Allen McGuire and published by . This book was released on 2012 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigating Fault System Deformation with Numerical Models and Analog Experiments written by Justin W. Herbert and published by . This book was released on 2014 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation aims to understand fault system deformation using numerical models and analog experiments. In southern California, the southern Big Bend of the San Andreas fault (SAF) is a zone of transpression that accommodates deformation associated with the Pacific-North American plate boundary. Using three-dimensional boundary element method (BEM) models, I test the sensitivity of fault slip rates to a range of tectonic boundary conditions constrained by Global Positioning System (GPS) studies of the region (45-50 mm/yr and 320°- 325°). I have modified fault configurations derived from the Southern California Earthquake Center Community Fault Model of the San Gorgonio knot and the eastern California shear zone (ECSZ) to better represent the disconnected nature of active faults in southern California. The models with revised fault geometry produce slip rates that better match geologic strike-slip rates, thus validating the revisions. More northerly plate velocity (325°) produces greater transpression along the SAF system associated with greater uplift of the San Bernardino Mountains, greater reverse-slip rates along range bounding reverse thrust faults, lower strike-slip rates along the San Andreas and San Jacinto faults, and greater strike-slip rates along the eastern California shear zone (ECSZ) and Garlock fault. These results suggest that the degree of regional transpression controls the partitioning of deformation between uplift and slip along both the SAF system and the ECSZ. Along the San Bernardino strand of the SAF and across the ECSZ, geologic slip rates differ from those inverted from geodetic measurements, which may partly be due to inaccurate fault connectivity within geodetic models. I compare results from fault networks that follow mapped geologic traces and resemble those used in block model inversions, which connect the San Jacinto fault to the SAF near Cajon Pass and connect distinct faults within the ECSZ. The connection of the SAF with the San Jacinto fault decreases strike-slip rates along the SAF by up to 10% and increases strike-slip rates along the San Jacinto fault by up to 16%; however, slip rate changes are still within the large geologic ranges along the SAF. The insensitivity of modeled interseismic surface velocities near Cajon Pass to fault connection suggests that inverse models may utilize both an incorrect fault geometry and slip rate and still provide an excellent fit to interseismic geodetic data. Similarly, connection of faults within the ECSZ produces 36% greater cumulative strike-slip rates but less than 17% increase in interseismic velocity. Within the models that follow the mapped traces, off-fault deformation accounts for 40% ± 23% of the total strain across the ECSZ. This suggests that a significant portion of the discrepancy between the geologic and geodetically modeled slip rates in the ECSZ could be due to the geodetic inversion model assumption of zero permanent off-fault deformation. When using overconnected models to invert GPS for slip rates, the reduced off-fault deformation within the models can lead to overprediction of slip rates. Analog models of sandbox experiments performed at the Universite de Cergy-Pontoise (UCP) shed light on the amount of work required to create faults (Wgrow) in coarse sand. Casagrande shear experiments calculate a Wgrow that is consistent with that calculated in the sandbox and both values scale properly to crustal calculations. Calculations of Wgrow are higher for thicker sand pack layer experiments. Utilizing different materials within the compressional sandbox (GA39 sand and glass beads) shows the control of material properties on Wgrow as well. Numerical simulations of the UCP sandbox experiments test whether fault growth occurs via work minimization. To the first order, faults observed in sandbox experiments match the model predicted faults that minimize work in two-dimensional BEM simulations. The BEM models and work minimization shed light on fault growth path and timing.
Download or read book Exhumation Associated with Continental Strike slip Fault Systems written by Alison B. Till and published by Geological Society of America. This book was released on 2007-01-01 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinematics of Transrotational Tectonism in the California Transverse Ranges and Its Contribution to Cumulative Slip Along the San Andreas Transform Fault System written by William R. Dickinson and published by Geological Society of America. This book was released on 1996-01-01 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tectonic Geomorphology of Mountains written by William B. Bull and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: With a balance of theory and practical applications, Tectonic Geomorphology of Mountains is essential reading for research geologists and upper-level undergraduate and graduate students in the earth sciences. This book describes how tectonic events influence geomorphic processes and explores how landscapes respond to tectonic deformation in the ways in which they are weathered, washed, and abraded Uses new approaches to enhance theoretical models of landscape evolution and to solve practical problems such as the assessment of earthquake hazards Includes previously unpublished research and theory Examines how to use key landforms as reference levels in changing landscapes, estimate rates of mountain-range uplift, and map seismic shaking caused by prehistorical earthquakes Presents a diverse range of examples from around the world
Download or read book Kinematics of the Calaveras Fault San Francisco Bay Area California Based on Inversion of Geodetic and Seismic Data written by David Martin Manaker and published by . This book was released on 1999 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deformation Associated with the Neogene Eastern California Shear Zone Southeastern California and Southwestern Arizona written by and published by . This book was released on 1992 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deformation of Compliant Fault Zones Induced by Nearby Earthquakes written by Jingqian Kang and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using dynamic modeling of earthquake rupture on a strike-slip fault and seismic wave propagation in a three dimensional inhomogeneous elastoplastic medium, I investigate the inelastic response of compliant fault zones to nearby earthquakes. I primarily examine the plastic strain distribution within the fault zone and the displacement field that characterizes the effects of the presence of the fault zone. I find that when the fault zone rocks are close to failure in the prestress field, plastic strain occurs along the entire fault zone near the Earth's surface and some portions of the fault zone in the extensional quadrant at depth, while the remaining portion deforms elastically. Plastic strain enhances the surface displacement of the fault zone, and the enhancement in the extensional quadrant is stronger than that in the compressive quadrant. These findings suggest that taking into account both elastic and inelastic deformation of fault zones to nearby earthquakes may improve our estimations of fault zone structure and properties from small-scale surface deformation signals. Furthermore, identifying the inelastic response of nearby fault zones to large earthquakes may allow us to place some constraints on the absolute stress level in the crust. I also investigate how to distinguish inelastic and elastic responses of compliant fault zones to the nearby rupture. I explore in detail the range of plastic parameters that allow plastic strain to occur and examine its effect on the displacement field around compliant fault zone. I find that the sympathetic motion (i.e., consistent to long-term geologic slip) or the reduced retrograde motion (i.e., opposite to long-term geologic slip) observed in residual displacement on fault parallel horizontal direction can be directly used to distinguish the inelastic deformation from the elastic deformation. This may help better interpret the geodetic observations in the further. In addition, I conduct models with various fault zone geometries (i.e., depth, width and shape) and rigidity reduction properties to test their effects on the displacement field. The results from elastic models suggest that to the same dynamic rupture source, the deeper and wider pre-existing nearby fault zone will result in larger residual displacement. But this only applies to fault zones with large depth extent. For shallow fault zones, residual displacement tends to keep the same magnitude or even decreases with fault zone width. While in plastic models, where plastic strain is allowed, displacement field is more complex. The magnitude of the residual displacement will be enhanced by the occurrence of plastic strain. Then I extend the theoretical simulations of an idealized planar rupture fault system into one in a geometrically complex real fault system in the East California Shear Zone (ECSZ). I compare our simulation results of the 1992 Landers Earthquake with the geodetic observations. Responses of the Calico and Rodman compliant fault zone are better understood by taking into account of both inelastic and elastic responses of compliant fault zones to the nearby Landers rupture. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/152529
Download or read book Kinematic Models of Deformation in Southern California Constrained by Geologic and Geodetic Data written by Lori A. Eich and published by . This book was released on 2006 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using a standardized fault geometry based on the Community Block Model, we create two analytic block models of the southern California fault system. We constrain one model with only geodetic data. In the other, we assign a priori slip rates to the San Andreas, Garlock, Helendale, Newport-Inglewood, Owens Valley, Sierra Madre, and Chino faults to create a joint geologic and geodetic model, using the a priori slip rates to refine the results in areas with limited geodetic data. Our results for the San Andreas fault are consistent with geologic slip rates in the north and south, but across the Big Bend area we find its slip rates to be slower than geologic rates. Our geodetic model shows right lateral slip rates of 19.8 + 1.3 mm/yr in the Mojave area and 17.3 ± 1.6 mm/yr near the Imperial fault; the San Gorgonio Pass area displays a left lateral slip rate of 1.8 + 1.7 mm/yr. Our joint geologic and geodetic model results include right lateral slip rates of 18.6 + 1.2 mm/yr in the Mojave area, 22.1 ± 1.6 mm/yr near the Imperial fault, and 9.5 1.4 mm/yr in the San Gorgonio Pass area. Both models show high values (10-13 1 mm/yr) of right lateral slip to the east of the Blackwater fault along the Goldstone, Calico, and Hidalgo faults. We show that substantially different block geometries in the Mojave can produce statistically similar model results due to sparse geodetic data.
Download or read book Special Papers written by and published by . This book was released on 2007 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cenozoic Tectonics and Regional Geophysics of the Western Cordillera written by Robert Baer Smith and published by . This book was released on 1978 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petroleum Abstracts written by and published by . This book was released on 1993 with total page 1752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tectonics of Strike slip Restraining and Releasing Bends written by W. D. Cunningham and published by Geological Society of London. This book was released on 2007 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume addresses the tectonic complexity and diversity of strike-slip restraining and releasing bends with 18 contributions divided into four thematic sections: a topical review of fault bends and their global distribution; bends, sedimentary basins and earthquake hazards; restraining bends, transpressional deformation and basement controls on development; releasing bends, transtensional deformation and fluid flow.
Download or read book Spring Meeting written by American Geophysical Union. Meeting and published by . This book was released on 1999 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt:
