Publications
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Slip-pulse rupture behavior on a 2 meter granite fault
We describe observations of dynamic rupture events that spontaneously arise on meter-scale laboratory earthquake experiments. While low-frequency slip of the granite sample occurs in a relatively uniform and crack-like manner, instruments capable of detecting high frequency motions show that some parts of the fault slip abruptly (velocity >100 mm∙s-1, acceleration >20 km∙s-2) while the majority of
Authors
Gregory C. McLaskey, Brian D. Kilgore, Nicholas M. Beeler
Numerical modeling of injection, stress and permeability enhancement during shear stimulation at the Desert Peak Enhanced Geothermal System
Creation of an Enhanced Geothermal System relies on stimulation of fracture permeability through self-propping shear failure that creates a complex fracture network with high surface area for efficient heat transfer. In 2010, shear stimulation was carried out in well 27-15 at Desert Peak geothermal field, Nevada, by injecting cold water at pressure less than the minimum principal stress. An order-
Authors
David Dempsey, Sharad Kelkar, Nick Davatzes, Stephen H. Hickman, Daniel Moos
High‐resolution trench photomosaics from image‐based modeling: Workflow and error analysis
Photomosaics are commonly used to construct maps of paleoseismic trench exposures, but the conventional process of manually using image‐editing software is time consuming and produces undesirable artifacts and distortions. Herein, we document and evaluate the application of image‐based modeling (IBM) for creating photomosaics and 3D models of paleoseismic trench exposures, illustrated with a case‐
Authors
Nadine G. Reitman, Scott E. K. Bennett, Ryan D. Gold, Richard W. Briggs, Christopher DuRoss
Evidence for slip partitioning and bimodal slip behavior on a single fault: Surface slip characteristics of the 2013 Mw7.7 Balochistan, Pakistan earthquake
Deformation is commonly accommodated by strain partitioning on multiple, independent strike-slip and dip-slip faults in continental settings of oblique plate convergence. As a corollary, individual faults tend to exhibit one sense of slip – normal, reverse, or strike-slip – until whole-scale changes in boundary conditions reactivate preexisting faults in a new deformation regime. In this study, we
Authors
William D. Barnhart, Richard W. Briggs, Nadine G. Reitman, Ryan D. Gold, Gavin P. Hayes
Time-varying interseismic strain rates and similar seismic ruptures on the Nias-Simeulue patch of the Sunda megathrust
Fossil coral microatolls from fringing reefs above the great (MW 8.6) megathrust rupture of 2005 record uplift during the historically reported great earthquake of 1861. Such evidence spans nearly the entire 400-km strike length of the 2005 rupture, which was previously shown to be bounded by two persistent barriers to seismic rupture. Moreover, at sites where we have constrained the 1861 uplift a
Authors
Aron J. Meltzner, Kerry E. Sieh, Hong-Wei Chiang, Chung-Che Wu, Louisa L.H. Tsang, Chuan-Chou Shen, Emma M. Hill, Bambang W. Suwargadi, Danny H. Natawidjaja, Belle Philibosian, Richard W. Briggs
Thin‐ or thick‐skinned faulting in the Yakima fold and thrust belt (WA)? Constraints from kinematic modeling of the saddle mountains anticline
The Yakima fold and thrust belt (YFTB) deforms the Columbia River Basalt Group flows of Washington State. The YFTB fault geometries and slip rates are crucial parameters for seismic‐hazard assessments of nearby dams and nuclear facilities, yet there are competing models for the subsurface fault geometry involving shallowly rooted versus deeply rooted fault systems. The YFTB is also thought to be a
Authors
Gabriele Casale, Thomas L. Pratt
Paleoseismologic evidence for large-magnitude (Mw 7.5-8.0) earthquakes on the Ventura blind thrust fault: Implications for multifault ruptures in the Transverse Ranges of southern California
Detailed analysis of continuously cored boreholes and cone penetrometer tests (CPTs), high-resolution seismic-reflection data, and luminescence and 14C dates from Holocene strata folded above the tip of the Ventura blind thrust fault constrain the ages and displacements of the two (or more) most recent earthquakes. These two earthquakes, which are identified by a prominent surface fold scarp and a
Authors
Lee J. McAuliffe, James F. Dolan, Edward J. Rhodes, Judith Hubbard, John H. Shaw, Thomas L. Pratt
Kinematics of shallow backthrusts in the Seattle fault zone, Washington State
Near-surface thrust fault splays and antithetic backthrusts at the tips of major thrust fault systems can distribute slip across multiple shallow fault strands, complicating earthquake hazard analyses based on studies of surface faulting. The shallow expression of the fault strands forming the Seattle fault zone of Washington State shows the structural relationships and interactions between such f
Authors
Thomas L. Pratt, K.G. Troost, Jackson K. Odum, William J. Stephenson
Modifications to risk-targeted seismic design maps for subduction and near-fault hazards
ASCE 7-10 introduced new seismic design maps that define risk-targeted ground motions such that buildings designed according to these maps will have 1% chance of collapse in 50 years. These maps were developed by iterative risk calculation, wherein a generic building collapse fragility curve is convolved with the U.S. Geological Survey hazard curve until target risk criteria are met. Recent resear
Authors
Abbie B. Liel, Nicolas Luco, Meera Raghunandan, C. Champion
Paleoseismic evidence for late Holocene tectonic deformation along the Saddle mountain fault zone, Southeastern Olympic Peninsula, Washington
Trench and wetland coring studies show that northeast‐striking strands of the Saddle Mountain fault zone ruptured the ground about 1000 years ago, generating prominent scarps. Three conspicuous subparallel fault scarps can be traced for 15 km on Light Detection and Ranging (LiDAR) imagery, traversing the foothills of the southeast Olympic Mountains: the Saddle Mountain east fault, the Saddle Mount
Authors
Elizabeth Barnett, Brian L. Sherrod, Jonathan F. Hughes, Harvey M. Kelsey, Jessica L. Czajkowski, Timothy J. Walsh, Trevor A. Contreras, Elizabeth R. Schermer, Robert J. Carson
Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review
The study of mass and energy transfer across landscapes has recently evolved to comprehensive considerations acknowledging the role of biota and humans as geomorphic agents, as well as the importance of small-scale landscape features. A contributing and supporting factor to this evolution is the emergence over the last two decades of technologies able to acquire high resolution topography (HRT) (m
Authors
Paola Passaiacquaa, Patrick Belmont, Dennis M. Staley, Jeffery Simley, J. Ramon Arrowsmith, Collin A. Bode, Christopher Crosby, Stephen DeLong, Nancy Glenn, Sara Kelly, Dimitri Lague, Harish Sangireddy, Keelin Schaffrath, David Tarboton, Thad Wasklewicz, Joseph Wheaton
Relationships among seismic velocity, metamorphism, and seismic and aseismic fault slip in the Salton Sea Geothermal Field region
The Salton Sea Geothermal Field is one of the most geothermally and seismically active areas in California and presents an opportunity to study the effect of high-temperature metamorphism on the properties of seismogenic faults. The area includes numerous active tectonic faults that have recently been imaged with active source seismic reflection and refraction. We utilize the active source surveys
Authors
Jeffrey J. McGuire, Rowena B. Lohman, Rufus D. Catchings, Michael J. Rymer, Mark R. Goldman