Publications
Filter Total Items: 1858
Relatively stable pressure effects and time-increasing thermal contraction control Heber geothermal field deformation
Due to geological complexities and observational gaps, it is challenging to identify the governing physical processes of geothermal field deformation including ground subsidence and earthquakes. In the west and east regions of the Heber Geothermal Field (HGF), decade-long subsidence was occurring despite injection of heat-depleted brines, along with transient reversals between uplift and subsidenc
Authors
Guoyan Jiang, Andrew Barbour, Robert John Skoumal, Kathryn Zerbe Materna, Aren Crandall-Bear
Uncertainty in ground-motion-to-intensity conversions significantly affects earthquake early warning alert regions
We examine how the choice of ground‐motion‐to‐intensity conversion equations (GMICEs) in earthquake early warning (EEW) systems affects resulting alert regions. We find that existing GMICEs can underestimate observed shaking at short rupture distances or overestimate the extent of low‐intensity shaking. Updated GMICEs that remove these biases would improve the accuracy of alert regions for the Sha
Authors
Jessie Saunders, Annemarie S. Baltay, Sarah E. Minson, Maren Böse
The SCEC/USGS community stress drop validation study using the 2019 Ridgecrest earthquake sequence
We introduce a community stress drop validation study using the 2019 Ridgecrest, California, earthquake sequence, in which researchers are invited to use a common dataset to independently estimate comparable measurements using a variety of methods. Stress drop is the change in average shear stress on a fault during earthquake rupture, and as such is a key parameter in many ground motion, rupture s
Authors
Annemarie S. Baltay, Rachel E Abercrombie, Shanna Xianhui Chu, Taka'aki Taira
Elastic stress coupling between supraglacial lakes
Supraglacial lakes have been observed to drain within hours of each other, leading to the hypothesis that stress transmission following one drainage may be sufficient to induce hydro-fracture-driven drainages of other nearby lakes. However, available observations characterizing drainage-induced stress perturbations have been insufficient to evaluate this hypothesis. Here, we use ice-sheet surface-
Authors
L. Stevens, S. Das, M. D. Behn, Jeffrey McGuire, Ching-Yao Lai, I. Joughin, S LaRochelle, M. Nettles
Using open-science workflow tools to produce SCEC CyberShake physics-based probabilistic seismic hazard models
The Statewide (formerly Southern) California Earthquake Center (SCEC) conducts multidisciplinary earthquake system science research that aims to develop predictive models of earthquake processes, and to produce accurate seismic hazard information that can improve societal preparedness and resiliency to earthquake hazards. As part of this program, SCEC has developed the CyberShake platform, which c
Authors
Scott Callaghan, Phillip J. Maechling, Fabio Silva, Mei-Hui Su, Kevin R. Milner, Robert Graves, Kim Olsen, Yifeng Cui, Karan Vahi, Albert Kottke, Christine A Goulet, Ewa Deelman, Tom Jordan, Yehuda Ben-Zion
Investigating past earthquakes with coral microatolls
Intertidal corals (microatolls) preserve evidence of past uplift or subsidence with annual precision. Microatoll records are particularly useful along subduction zones, and can reveal past earthquake ruptures at a level of detail that is ordinarily limited to the instrumental era.
Authors
Belle E. Philibosian
Evaluation of 2-D shear-wave velocity models and VS30at six strong-motion recording stations in southern California using multichannel analysis of surface waves and refraction tomography
To better understand the potential for amplified ground shaking at sites that house critical infrastructure, the U.S. Geological Survey (USGS) evaluated shear-wave velocities (VS) at six strong-motion recording stations in Southern California Edison facilities in southern California. We calculated VS30 (time-averaged shear-wave velocity in the upper 30 meters [m]), which is a parameter used in gro
Authors
Joanne H. Chan, Rufus D. Catchings, Mark R. Goldman, Coyn J. Criley, Robert R. Sickler
Empirical ground-motion basin response in the California Great Valley, Reno, Nevada, and Portland, Oregon
We assess how well the Next-Generation Attenuation-West 2 (NGA-West2) ground-motion models (GMMs), which are used in the US Geological Survey’s (USGS) National Seismic Hazard Model (NSHM) for crustal faults in the western United States, predict the observed basin response in the Great Valley of California, the Reno basin in Nevada, and Portland and Tualatin basins in Oregon. These GMMs rely on sit
Authors
Sean Kamran Ahdi, Brad T. Aagaard, Morgan P. Moschetti, Grace Alexandra Parker, Oliver S. Boyd, William J. Stephenson
Preliminary implications of viscoelastic ray theory for anelastic seismic tomography models
The recent developments in general viscoelastic ray theory provide a rigorous mathematical framework for anelastic seismic tomography. They provide closed‐form solutions of forward ray‐tracing and simple inverse problems for anelastic horizontal and spherical layered media with material gradients. They provide ray‐tracing computation algorithms valid for all angles of incidence that account for ch
Authors
Roger D. Borcherdt
Performance-based earthquake early warning for tall buildings
The ShakeAlert Earthquake Early Warning (EEW) system aims to issue an advance warning to residents on the West Coast of the United States seconds before the ground shaking arrives, if the expected ground shaking exceeds a certain threshold. However, residents in tall buildings may experience much greater motion due to the dynamic response of the buildings. Therefore, there is an ongoing effort to
Authors
S. Farid Ghahari, Khachik Sargsyan, Grace Alexandra Parker, Dan Swensen, Mehmet Çelebi, Hamid Haddadi, Ertugrul Taciroglu
Summary of Creepmeter Data from 1980 to 2020—Measurements Spanning the Hayward, Calaveras, and San Andreas Faults in Northern and Central California
This report is an update to the presentation by Schulz (1989) introducing potential users to the creepmeter data collected between the publication of Schulz’s report and mid-2020. The creepmeter network monitors aseismic, surface slip at various locations on the Hayward, Calaveras, and San Andreas Faults in northern and central California. There are different designs of creepmeters and these are b
Authors
John Langbein, Roger G. Bilham, Hollice A. Snyder, Todd Ericksen
Distinct yet adjacent earthquake sequences near the Mendocino Triple Junction: 20 December 2021 Mw 6.1 and 6.0 Petrolia, and 20 December 2022 Mw 6.4 Ferndale
Two earthquake sequences occurred a year apart at the Mendocino Triple Junction in northern California: first the 20 December 2021 �w 6.1 and 6.0 Petrolia sequence, then the 20 December 2022 �w 6.4 Ferndale sequence. To delineate active faults and understand the relationship between these sequences, we applied an automated deep‐learning workflow to create enhanced and relocated earthquake catalogs
Authors
Clara Yoon, David R. Shelly