Publications
Filter Total Items: 2009
Seismic images and subsurface structures of northeastern Edwards Air Force Base, Kern County, California
We used multi-component seismic data (including two-dimensional images of compressional-wave velocity [vP], shear-wave velocity [vS], the ratio of compressional-wave velocity to shear-wave velocity [vP/vS ratio], Poisson’s ratio [μ], and seismic reflections) along a transect across northeastern Edwards Air Force Base to investigate the upper few hundred meters of the subsurface. The...
Authors
Rufus D. Catchings, Mark R. Goldman, Joanne H. Chan, Robert R. Sickler, Coyn J. Criley
Ground‐motion variability from kinematic rupture models and the implications for nonergodic probabilistic seismic hazard analysis
The variability of earthquake ground motions has a strong control on probabilistic seismic hazard analysis (PSHA), particularly for the low frequencies of exceedance used for critical facilities. We use a crossed mixed‐effects model to partition the variance components from simulated ground motions of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone. Total...
Authors
Grace Alexandra Parker, Morgan P. Moschetti, Eric M. Thompson
Comparison of earthquake early warning systems and the national volcano early warning system at the U.S. Geological Survey
IntroductionEvery year in the United States, natural hazards threaten lives and livelihoods, resulting in thousands of casualties and billions of dollars in damage. The U.S. Geological Survey (USGS) Natural Hazards Mission Area works with many partners to monitor, assess, and research a wide range of natural hazards, including earthquakes and volcanic eruptions. These efforts aim to...
Authors
Aleeza Wilkins, Charlie Mandeville, John Power, Douglas D. Given
Comment on "Multi-Event explosive seismic source for the 2022 Mw 6.3 Hunga Tonga submarine volcanic eruption" by Julien Thurin, Carl Tape, and Ryan Modrak
No abstract available.
Authors
Frederick Pollitz, Ricardo Garza-Giron, Thorne Lay
Scaling microseismic cloud shape during hydraulic stimulation using in-situ stress and permeability
Forecasting microseismic cloud shape as a proxy of stimulated rock volume may improve the design of an energy extraction system. The microseismic cloud created during hydraulic stimulation of geothermal reservoirs is known empirically to extend in the general direction of the maximum principal stress. However, this empirical relationship is often inconsistent with reported results, and...
Authors
Y. Mukuhira, M. Yang, T. Ishibashi, K. Okamoto, H. Moriya, Y. Kumano, H. Asanuma, S.A. Shapiro, Justin Rubinstein, T. Ito, K. Yan, Y. Zuo
Converted-wave reverse time migration imaging in subduction zone settings
We use a newly developed 2-D elastic reverse time migration (RTM) imaging algorithm based on the Helmholtz decomposition to test approaches for imaging the descending slab in subduction zone regions using local earthquake sources. Our elastic RTM method is designed to reconstruct incident and scattered wavefields at depth, isolate constituent P- and S-wave components via Helmholtz...
Authors
Leah Langer, Frederick Pollitz, Jeffrey J. McGuire
Accuracy of finite fault slip estimates in subduction zone regions with topographic Green's functions and seafloor geodesy
Until recently, the lack of seafloor geodetic instrumentation and the use of unrealistically simple, half-space based forward models have resulted in poor resolution of near-trench slip in subduction zone settings. Here, we use a synthetic framework to investigate the impact of topography and geodetic data distribution on coseismic slip estimates in various subduction zone settings. We...
Authors
Leah Langer, Théa Ragon
Slip deficit rates on southern Cascadia faults resolved with viscoelastic earthquake cycle modeling of geodetic deformation
The fore‐arc of the southern Cascadia subduction zone (CSZ), north of the Mendocino triple junction (MTJ), is home to a network of Quaternary‐active crustal faults that accumulate strain due to the interaction of the North American, Juan de Fuca (Gorda), and Pacific plates. These faults, including the Little Salmon and Mad River fault (LSF and MRF) zones, are located near the most...
Authors
Kathryn Zerbe Materna, Jessica R. Murray, Frederick Pollitz, Jason R. Patton
A detailed view of the 2020-2023 southwestern Puerto Rico seismic sequence with deep learning
The 2020–2023 southwestern Puerto Rico seismic sequence, still ongoing in 2023, is remarkable for its multiple‐fault rupture complexity and elevated aftershock productivity. We applied an automatic workflow to continuous data from 43 seismic stations in Puerto Rico to build an enhanced earthquake catalog with ∼180,000 events for the 3+ yr sequence from 28 December 2019 to 1 January 2023...
Authors
Clara Yoon, Elizabeth S. Cochran, Elizabeth A. Vanacore, Victor Huerfano, Gisela Báez-Sánchez, John D. Wilding, Jonathan D. Smith
Uncertainties in intensity-based earthquake magnitude estimates
Estimating the magnitude of historical earthquakes is crucial for assessing seismic hazard. Magnitudes of early‐instrumental earthquakes can be inferred using a combination of instrumental records, field observations, and the observed distribution of shaking intensity determined from macroseismic observations. For earthquakes before 1900, shaking intensity distributions often provide the...
Authors
Madeleine C. Lucas, Susan E. Hough, Seth Stein, Leah Marschall Salditch, Molly M. Gallahue, James S. Neely, Norman A. Abrahamson
Modern products for a vintage event: An update on the 1933 Long Beach, California, earthquake
When a notable earthquake occurs in the United States, a range of familiar real‐ and near‐real‐time products are produced by the U.S. Geological Survey (USGS) Advanced National Seismic System (ANSS), and made available via the ANSS Comprehensive Earthquake Catalog. For historical and early instrumental earthquakes, similar results and products are developed depending on data availability...
Authors
Susan E. Hough, J. Luke Blair, Sonia Ellison, Robert Graves, Scott Haefner, Eric M. Thompson, Nicholas van der Elst, Morgan T. Page, David J. Wald
Witnessing history: Comparison of a century of sedimentary and written records in a California protected area
We use a combination of proxy records from a high-resolution analysis of sediments from Searsville Lake and adjacent Upper Lake Marsh and historical records to document over one and a half centuries of vegetation and socio-ecological change—relating to logging, agricultural land use change, dam construction, chemical applications, recreation, and other drivers—on the San Francisco...
Authors
R. Scott Anderson, M. Allison Stegner, SeanPaul La Selle, Brian Sherrod, Anthony D. Barnosky, Elizabeth A. Hadly