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Comparison of nonergodic ground-motion components from CyberShake and NGA-West2 datasets in California

In this study, we compare the Southern California Earthquake Center CyberShake platform against the Next Generation Attenuation‐West2 empirical datasets. Because the CyberShake and empirical datasets cover very different magnitude ranges and site conditions, we develop ground‐motion models (GMMs) for CyberShake datasets to compare trends with empirical GMMs and decompose the residuals for further
Xiaofeng Meng, Christine Goulet, Kevin R. Milner, Robert Graves, Scott Callaghan

Incorporating uncertainty in susceptibility criteria into probabilistic liquefaction hazard analysis

Most conventional approaches for assessing liquefaction triggering hazards generally rely on simplified procedures that involve identifying liquefaction susceptible layers and calculating a factor of safety against liquefaction (FSL) in each layer. Such procedures utilize deterministic semi-empirical models for standard penetration test (SPT), cone penetrometer test (CPT), or shear wave velocity (
Andrew James Makdisi

Chemical characterization of San Andreas Fault Observatory at Depth (SAFOD) Phase 3 core

We present new X-ray fluorescence compositions of 27 core samples from Phase 3, Hole G of the San Andreas Fault Observatory at Depth, nearly doubling the published dataset for the core. The new analyses consist of major and trace element compositions and the first published data for rare earth elements from Hole G. Whole-rock compositions were obtained to further the analysis of active geochemical
Diane E. Moore, Kelly K. Bradbury

Surface fault displacement models for strike-slip faults

Fault displacement models (FDMs) are an essential component of the probabilistic fault displacement hazard analyses (PFDHA), much like ground motion models in the probabilistic seismic hazard analyses for ground motion hazards. In this study, we develop several principal surface FDMs for strike-slip earthquakes. The model development is based on analyses of the new and comprehensive fault displac
Brian S. J. Chiou, Rui Chen, Kate Thomas, Christopher W. D. Milliner, Timothy E. Dawson, Mark D. Petersen

Investigating spatio-temporal variability of initial 230Th/232Th in intertidal corals

One of the key factors in obtaining precise and accurate 230Th ages of corals, especially for corals with ages less than a few thousand years, is the correction for non-radiogenic 230Th based on an initial 230Th/232Th value (230Th/232Th0). Studies that consider coral 230Th/232Th0 values in intertidal environments are limited, and it is in these environments that corals have Th concentrations 100–1
Hong-Wei Chiang, Belle E. Philibosian, Aron J. Meltzner, Chung-Che Wu, Chuan-Chou Shen, R. Lawrence Edwards, Chih-Kai Chuang, Bambang W. Suwargadi, Danny H. Natawidjaja

Magnitude conversion and earthquake recurrence rate models for the central and eastern United States

Development of Seismic Source Characterization (SSC) models, which is an essential part of Probabilistic Seismic Hazard Analyses (PSHA), can help forecast the temporal and spatial distribution of future damaging earthquakes (𝑀w≥ 5) in seismically active regions. Because it is impossible to associate all earthquakes with known faults, seismic source models for PSHA often include sources of diffuse
Rasool Anooshehpoor, Thomas Weaver, Jon Ake, Cliff Munson, Morgan P. Moschetti, David R. Shelly, Peter M. Powers

60 years and beyond of Reviews of Geophysics

Reviews of Geophysics is an AGU journal, first established in February 1963. It is a hybrid open access invitation-only journal that publishes comprehensive review articles across various disciplines within the Earth and Space Sciences. The selection criteria are rigorous and many submissions are declined without review. The journal is the highest ranked in the fields of Geochemistry and Geophysic
Fabio Florindo, Valerio Acocella, Ann Marie Carlton, Paolo D’Odorico, Qingyun Duan, Andrew Gettelman, Jasper Halekas, Ruth A. Harris, Gesine Mollenhauer, Alan Robock, Claudine Stirling, Yusuke Yokoyama

Dense geophysical observations reveal a triggered, concurrent multi-fault rupture at the Mendocino Triple Junction

A central question of earthquake science is how far ruptures can jump from one fault to another, because cascading ruptures can increase the shaking of a seismic event. Earthquake science relies on earthquake catalogs and therefore how complex ruptures get documented and cataloged has important implications. Recent investments in geophysical instrumentation allow us to resolve increasingly complex
William L. Yeck, David R. Shelly, Dara Elyse Goldberg, Kathryn Zerbe Materna, Paul S. Earle

High-pass corner frequency selection for implementation in the USGS automated ground motion processing tool

Earthquake ground motion processing for next-generation attenuation (NGA) projects required human inspection to select high-pass corner frequencies (fcHP), which is time-intensive and subjective. With growth in the number of recordings per event and interest in enhancing repeatability, we sought to develop automated procedures for fcHP selection. These procedures consider signal-to-noise ratio (SN
María E. Ramos-Sepulveda, Grace Alexandra Parker, Eric M. Thompson, Scott J. Brandenberg, Meibai Li, Okan Ilhan, Youssef M.A. Hashash, Ellen M. Rathje, Jonathan P. Stewart

Fault roughness at seismogenic depths and links to earthquake behavior

Fault geometry affects the initiation, propagation, and cessation of earthquake rupture, as well as, potentially, the statistical behavior of earthquake sequences. We analyze 18,250 (−0.27
Elizabeth S. Cochran, Morgan T. Page, Nicholas van der Elst, Zachary E. Ross, Daniel T. Trugman

January 12, 2023 SCEC workshop, Dynamic Rupture TAG – Investigating new ideas in earthquake source mechanics(SCEC Project 22157)

The Southern California Earthquake Center (SCEC) workshop “Dynamic Rupture TAG – Investigating New Ideas in Earthquake Source Mechanics” was convened on Zoom on January 12, 2023. A total of 60 people participated. Our workshop attendees included scientists from 28 institutions and 11 countries (United States of America, Australia, Brazil, Czech Republic, China, France, Germany, Japan, New Zealan
Ruth A. Harris, Michael Barall

Incorporation of real-time earthquake magnitudes estimated via peak ground displacement scaling in the ShakeAlert Earthquake Early Warning system

The United States earthquake early warning (EEW) system, ShakeAlert®, currently employs two algorithms based on seismic data alone to characterize the earthquake source, reporting the weighted average of their magnitude estimates. Nonsaturating magnitude estimates derived in real time from Global Navigation Satellite System (GNSS) data using peak ground displacement (PGD) scaling relationships off
Jessica R. Murray, Brendan W. Crowell, Mark Hunter Murray, Carl W Ulberg, Jeffrey McGuire, Mario Aranha, Mike Hagerty