Download or read book Rock properties and structure within the San Andreas Fault Observatory at Depth SAFOD borehole northwest of Parkfield California written by Kelly Keighley Bradbury and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rock Properties and Structure Within the San Andreas Fault Observatory at Depth SAFOD Borehold Northwest of Parkfield California written by Kelly Keighley Bradbury and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integration of the Physical and Chemical Rock Properties Structure and Permeability of the San Andreas Fault San Andreas Fault Observatory at Depth Borehole California written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Three Dimensional Structure and Earthquake Locations Along the San Andreas Fault Near Parkfield California written by Kyle A. Roberts and published by . This book was released on 2003 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Treatise on Geophysics written by and published by Elsevier. This book was released on 2015-04-17 with total page 5604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treatise on Geophysics, Second Edition, is a comprehensive and in-depth study of the physics of the Earth beyond what any geophysics text has provided previously. Thoroughly revised and updated, it provides fundamental and state-of-the-art discussion of all aspects of geophysics. A highlight of the second edition is a new volume on Near Surface Geophysics that discusses the role of geophysics in the exploitation and conservation of natural resources and the assessment of degradation of natural systems by pollution. Additional features include new material in the Planets and Moon, Mantle Dynamics, Core Dynamics, Crustal and Lithosphere Dynamics, Evolution of the Earth, and Geodesy volumes. New material is also presented on the uses of Earth gravity measurements. This title is essential for professionals, researchers, professors, and advanced undergraduate and graduate students in the fields of Geophysics and Earth system science. Comprehensive and detailed coverage of all aspects of geophysics Fundamental and state-of-the-art discussions of all research topics Integration of topics into a coherent whole
Download or read book Geology of the Earthquake Source written by Åke Fagereng and published by Geological Society of London. This book was released on 2011 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Professor Richard (Rick) Sibson revolutionized structural geology by illustrating that fault rocks contain an integrated record of earthquakes. Fault-rock textures develop in response to geological and physical variables such as composition, environmental conditions (e.g. temperature and pressure), fluid presence and strain rate. These parameters also determine the rate- and state-variable frictional stability of a fault, the dominant mineral deformation mechanism and shear strength, and ultimately control the partitioning between seismic and aseismic deformation. This volume contains a collection of papers that address the geological record of earthquake faulting from field-based or theoretical perspectives.
Download or read book Thermo Hydromechanical and Chemical Coupling in Geomaterials and Applications written by Jian-Fu Shao and published by John Wiley & Sons. This book was released on 2013-05-10 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: GeoProc2008 collects the proceedings of the International Conference on Coupled T-H-M-C (thermal, hydraulic, mechanical, chemical) Processes in Geosystems.
Download or read book Imaging Modeling and Assimilation in Seismology written by Yong-Gang Li and published by Walter de Gruyter. This book was released on 2012-02-22 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents current approaches in geophysical research of earthquakes. A global authorship from top institutions presents case studies to model, measure, and monitor earthquakes. Among others a full-3D waveform tomography method is introduced, as well as propagator methods for modeling and imaging. In particular the earthquake prediction method makes this book a must-read for researchers in the field.
Download or read book Displacement Along the San Andreas Fault California written by John C. Crowell and published by Geological Society of America. This book was released on 1962 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Grain scale Comminution and Alteration of Arkosic Rocks in the Damage Zone of the San Andreas Fault at Safod written by Bretani Rebecca Heron and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Spot core from the San Andreas Fault Observatory at Depth (SAFOD) borehole provides the opportunity to characterize and quantify damage and mineral alteration of siliciclastics within an active, large-displacement plate-boundary fault zone. Deformed arkosic, coarse-grained, pebbly sandstone, and fine-grained sandstone and siltstone retrieved from 2.55 km depth represent the western damaged zone of the San Andreas Fault, approximately 130 m west of the Southwest Deforming Zone (SDZ). The sandstone is cut by numerous subsidiary faults that display extensive evidence of repeating episodes of compaction, shear, dilation, and cementation. The subsidiary faults are grouped into three size classes: 1) small faults, 1 to 2 mm thick, that record an early stage of fault development, 2) intermediate-size faults, 2 to 3 mm thick, that show cataclastic grain size reduction and flow, extensive cementation, and alteration of host particles, and 3) large subsidiary faults that have cemented cataclastic zones up to 10 mm thick. The cataclasites contain fractured host-rock particles of quartz, oligoclase, and orthoclase, in addition to albite and laumontite produced by syn-deformation alteration reactions. Five structural units are distinguished in the subsidiary fault zones: fractured sandstones, brecciated sandstones, microbreccias, microbreccias within distinct shear zones, and principal slip surfaces. We have quantified the particle size distributions and the particle shape of the host rock mineral phases and the volume fraction of the alteration products for these representative structural units. Shape characteristics vary as a function of shear strain and grain size, with smooth, more circular particles evolving as a result of increasing shear strain. Overall, the particle sizes are consistent with a power law distribution over the particle size range investigated (0.3 ℗æm
Download or read book A COCORP Deep Seismic Reflection Profile Across the San Andreas Fault Parkfield California written by George Henry Long and published by . This book was released on 1981 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Frictional Strength of the Creeping Segment of the San Andreas Fault written by Clayton Gage Coble and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The San Andreas Fault (SAF) near Parkfield, CA moves by a combination of aseismic creep and micro-earthquake slip. Measurements of in situ stress orientation, stress magnitude, and heat flow are incompatible with an average shear stress on the SAF greater than approximately 20 MPa. To investigate the micro-mechanical processes responsible for the low strength and creeping behavior, gouge samples from the 3 km-deep scientific borehole near Parkfield (the San Andreas Fault Observatory at Depth, SAFOD) are sheared in a triaxial rock deformation apparatus at conditions simulating those in situ, specifically a temperature of 100°C, effective normal stress of 100 MPa, pore fluid pressure of 25 MPa, and a Na-Ca-K pore fluid chemistry. The 2 mm-thick gouge layers are sheared to 4.25 mm at shear rates of 6.0, 0.6, 0.06, and 0.006 mu m/s. The mechanical data are corrected for apparatus effects and the strength of the jacketing material that isolates the sample from the confining fluid. Experiments indicate that gouge is extremely weak with a coefficient of friction of 0.14, and displays velocity and temperature strengthening behavior. The frictional behavior is consistent with the inferred in situ stress and aseismic creep observed at SAFOD. The low frictional strength likely reflects the presence of a natural fabric characterized by microscale folia containing smectite and serpentinite.
Download or read book The Fabric of Clasts Veins and Foliations Within the Actively Creeping Zones of the San Andreas Fault at Safod written by David Wayne Sills and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recovered core samples from the San Andreas Fault Observatory at Depth (SAFOD), located near Parkfield, CA, offer a unique opportunity to study the products of faulting and to learn about the mechanisms of slip at 3 km depth. Casing deformation reflects active creep along two strands of the San Andreas Fault (SAF) at SAFOD. The two fault strands are referred to as the Southwest Deforming Zone (SDZ) at 3194 m measured depth (MD) and the Central Deforming Zone (CDZ) at 3301 m MD. The SDZ and CDZ contain remarkably similar gouge layers, both of which consist of a clay-bearing, ultrafine grain matrix containing survivor clasts of sandstone and serpentinite. The two gouges have sharp boundary contacts with the adjacent rocks. We have used X-ray Computed Tomography (XCT) imaging, at two different sampling resolutions, to investigate the mesoscale and microscale structure of the fault zone, specifically to characterize the shape, preferred orientation, and size distribution of the survivor clasts. Using various image processing techniques, survivor clast shape and size are characterized in 3D by best-fit ellipsoids. Renderings of survivor clasts illustrate that survivor clasts have fine tips reminiscent of sigma type tails of porphyroclasts observed in myolonites. The resolution of the XCT imaging permits characterization of survivor clasts with equivalent spherical diameters greater than 0.63 mm. The survivor clast population in both the SDZ and CDZ gouge layers have similar particle size distributions (PSD) which fit a power law with a slope of approximately -3; aspect ratio (major to minor axis ratios) distributions also are similar throughout ranging between 1.5 and 4, with the majority occurring between 2-2.5. The volume- and shape- distributions vary little with position across the gouge zones. A strong shape preferred orientation (SPO) exists in both creeping zones. In both the SDZ and CDZ the minor axes form a SPO approximately normal to the plane of the San Andreas Fault (SAF), and the major axes define a lineation in the plane of the SAF. The observation that the size-, shape- and orientation-distributions of mesoscale, matrix-supported clasts are similar in the SDZ and CDZ gouge layers, and vary little with position in each gouge layer, is consistent with the hypothesis that aseismic creep in the SDZ and CDZ is achieved by distributed, shearing. The consistency between the SPO and simple-shear, strike-slip kinematics, and the marked difference of PSD, fabric, cohesion and clast lithology of the gouge with that of the adjacent rock, is consistent with the hypothesis that the vast majority of the shear displacement on the SAF at SAFOD is accommodated within the gouge layers and the gouge displays a mature, nearly steady-state structure.
Download or read book Where s the San Andreas Fault written by Philip Ward Stoffer and published by . This book was released on 2006 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mesoscale Fracture Fabric and Paleostress Along the San Andreas Fault at SAFOD written by Rafael Vladimir Almeida and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Spot cores from Phase 1 drilling of the main borehole at the San Andreas Fault Observatory at Depth (SAFOD) were mapped to characterize the mesoscale structure and infer paleostress at depth. Cores were oriented by comparing mapped structures with image logs of the borehole. The upper core (1476-1484 m measured depth, MD) is a medium-grained, weakly foliated, hornblende-biotite granodiorite containing leucocratic phenocrysts and lenses. Principal structures are sub-vertical veins, shallow dipping shears, and natural fractures of unknown kinematics. The features are compatible with horizontal extension and right-lateral, normal, oblique-slip on faults striking approximately parallel to the SAF. The lower core (3055.6-3067.2 m MD) has massivebedded, pebble conglomerates and coarse to fine grained arkosic sandstones grade into siltstones. Principal structure features are conjugate shears and two minor faults. The fracture fabric is consistent with strike-slip faulting and a maximum principal compressive paleostress at ~80° to the SAF plane. This paleostress is essentially parallel to the current in situ stress measured in the main borehole and to paleostresses inferred from fracture fabrics in exhumed faults of the San Andreas system to the south. The similarity between the current state of stress and paleostress states supports the suggestion that the maximum principal compressive stress direction is, on average, at high angles to the SAF and that the fault has been weak over geologic time.
Download or read book P Wave Study of the San Andreas Fault Near Parkfield CA from Ambient Noise Interferometry of Borehole Seismic Data written by Stephen Mosher and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, we investigate and develop the optimal data processing procedures necessary to recover Green's functions for body waves propagating among a network of borehole seismometers near Parkfield, CA. Applying these procedures, we detect P-waves propagating among these stations, which allows us to produce a first-order crustal velocity model for the San Andreas Fault in the Parkfield region. We also discuss under what conditions body wave phenomena such as reflections and mode conversions (P to S) may be observed, as further observing these would provide a dramatic improvement in our ability to characterize seismic velocity structures. Finally, we discuss the potential of seismic interferometry to produce time-lapse body wave characterizations of the San Andreas Fault, in which properties of the fault can be seen to change in time.
Download or read book Field Guide to the San Andreas Fault written by David K. Lynch and published by . This book was released on 2006 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
