Publications
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Episodic evolution of a protracted convergent margin revealed by detrital zircon geochronology in the Greater Caucasus
Convergent margins play a fundamental role in the construction and modification of Earth's lithosphere and are characterized by poorly understood episodic processes that occur during the progression from subduction to terminal collision. On the northern margin of the active Arabia-Eurasia collision zone, the Greater Caucasus Mountains provide an opportunity to study a protracted convergent margin
Authors
Dylan A Vasey, Leslie Garcia, Eric S. Cowgill, Charles Cashman Trexler, Tea Godoladze
Evidence for fine-grained material at lunar red spots: Insights from thermal infrared and radar data sets
Lunar red spots are small spectrally red features that have been proposed to be the result of non-mare volcanism. Studies have shown that a number of red spots are silicic, and are spectrally distinct from both highlands and mare compositions. In this work, we use data from LRO Diviner, Mini-RF, and Arecibo to investigate the material properties of 10 red spots. We create albedo maps using Diviner
Authors
Benjamin Byron, Catherine Elder, Timothy Glotch, Paul Hayne, Lori M Pigue, Joshua T. S. Cahill
Crustal thickness and the VP/VS ratio within the Arabia Plate from P-wave receiver functions at 154 broadband seismic stations
As part of a joint Saudi Geological Survey (SGS) and United States Geological Survey project, we analyzed P-wave receiver functions from seismic stations covering most of the Kingdom of Saudi Arabia to map the thickness of the crust across the Arabia Plate. We present an update of crustal thickness estimates and fill in gaps for the western Arabian Shield and the rifted margin at the Red Sea (the
Authors
Alexander R. Blanchette, Simon L. Klemperer, Walter D. Mooney
Shallow fault slip of the 2020 M5.1 Sparta, North Carolina, earthquake
The 2020 M 5.1 Sparta, North Carolina, earthquake is the largest in the eastern United States since the 2011 M 5.8 Mineral, Virginia, earthquake and produced a ∼2.5‐km‐long surface rupture, unusual for an event of this magnitude. A geological field study conducted soon after the event indicates oblique slip along a east‐southeast‐trending fault with a consistently observed thrust component. My ana
Authors
Fred Pollitz
a-positive: A robust estimator of the earthquake rate in incomplete or saturated catalogs
Detection thresholds in earthquake catalogs frequently change in time due to station coverage improvements and network saturation effects during active periods such as mainshock-aftershock cascades. This presents a challenge to seismicity-rate estimation; there is a tradeoff between using as low a minimum magnitude as possible to maximize data while not undercounting the rate due to catalog incomp
Authors
Nicholas van der Elst, Morgan T. Page
Summary of the history and research of the U.S. Geological Survey gas hydrate properties laboratory in Menlo Park, California, active from 1993 to 2022
The U.S. Geological Survey (USGS) Clathrate Hydrate Properties Project, active from 1993 to 2022 in Menlo Park, California, stemmed from an earlier project on the properties of planetary ices supported by the National Aeronautics and Space Administration’s (NASA’s) Planetary Geology and Geophysics Program. We took a material science approach in both projects, emphasizing chemical purity of samples
Authors
Laura A. Stern, Stephen H. Kirby
3-D wave propagation simulations of Mw 6.5+ earthquakes on the Tacoma Fault, Washington state, considering the effects of topography, a geotechnical gradient, and a fault damage zone
We simulate shaking in Tacoma, Washington, and surrounding areas from Mw 6.5 and 7.0 earthquakes on the Tacoma fault. Ground motions are directly modeled up to 2.5 Hz using kinematic, finite‐fault sources; a 3D seismic velocity model considering regional geology; and a model mesh with 30 m sampling at the ground surface. In addition, we explore how adjustments to the seismic velocity model affect
Authors
Ian Patrick Stone, Erin Wirth, Alex R. R. Grant, Arthur Frankel
Quantifying site effects and their influence on earthquake source parameter estimations using a dense array in Oklahoma
We investigate the effects of site response on source parameter estimates using earthquakes recorded by the LArge-n Seismic Survey in Oklahoma (LASSO). While it is well known that near-surface unconsolidated sediments can cause an apparent breakdown of earthquake self-similarity, the influence of laterally varying site conditions remains unclear. We analyze site conditions across the 1825-station
Authors
Hilary Chang, Rachel E. Abercrombie, Nori Nakata, Colin Pennington, Kilian B. Kemna, Elizabeth S. Cochran, Rebecca M. Harrington
Exploring the interior of Europa with the Europa Clipper
The Galileo mission to Jupiter revealed that Europa is an ocean world. The Galileo magnetometer experiment in particular provided strong evidence for a salty subsurface ocean beneath the ice shell, likely in contact with the rocky core. Within the ice shell and ocean, a number of tectonic and geodynamic processes may operate today or have operated at some point in the past, including solid ice con
Authors
James Roberts, William B. McKinnon, Catherine Elder, Gabriel Tobie, John Biersteker, Duncan Young, Ryan S. Park, Gregor Steinbrügge, Francis Nimmo, Samuel Howell, Julie C. Castillo-Rogez, Morgan Cable, Jacob Abrahams, Michael T. Bland, Chase Chivers, Corey Cochrane, Andrew Dombard, Carolyn M. Ernst, Antonio Genova, Christopher Gerekos, Christopher R. Glein, Camilla Harris, Hamish Hay, Paul O. Hayne, Matthew Hedman, Hauke Hussmann, Xianzhe Jia, Krishan Khurana, Walter Kiefer, Randolph L. Kirk, Margaret Kivelson, Justin D. Lawrence, Erin J. Leonard, Jonathan Lunine, Erwan Mazarico, Thomas B. McCord, Alfred S. McEwen, Carol Paty, Lynnae Quick, Carol A. Raymond, Kurt Retherford, Lorenz Roth, Abigail Rymer, Joachim Saur, Kirk Scanlan, Dustin Schroeder, David Senske, Wencheng Shao, Krista Soderlund, Elizabeth Spiers, Marshall Styczinski, Paolo Tortora, Steven Vance, Michaela Villarreal, Benjamin Weiss, Joseph Westlake, Paul Withers, Natalie Wolfenbarger, Bonnie J. Buratti, Haje Korth, Robert Pappalardo, Interior Thematic Working Group
Learnings from rapid response efforts to remotely detect landslides triggered by the August 2021 Nippes earthquake and Tropical Storm Grace in Haiti
On August 14, 2021, a Mw 7.2 earthquake struck the Tiburon Peninsula of western Haiti triggering thousands of landslides. Three days after the earthquake on August 17, 2021, Tropical Storm Grace crossed shallow waters offshore of southern Haiti triggering more landslides worsening the situation. In the aftermath of these events, several organizations with disaster response capabilities or programs
Authors
Pukar Amatya, Corey Scheip, Aline Déprez, Jean-Philippe Malet, Stephen L. Slaughter, Alexander L. Handwerger, Robert Emberson, Dalia Kirschbaum, Julien Jean-Baptiste, Mong-Han Huang, Marin Clark, Dimitrios Zekkos, Jhih-Rou Huang, Fabrizio Pacini, Enguerran Boissier
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 shallow subsur
Authors
Rufus D. Catchings, Mark R. Goldman, Joanne H. Chan, Robert R. Sickler, Coyn J. Criley
Bedrock erosion by debris flows at Chalk Cliffs, Colorado, USA: Implications for bedrock channel evolution
Debris flow erosion into bedrock helps to set the pace of mountain denudation, but there are few empirical observations of this process. We studied the effects of debris flows on bedrock erosion using Structure-From-Motion photogrammetry and multiple real-time monitoring measurements. We found that the distribution of bedrock erosion across the channel cross-section could be generalized as an expo
Authors
Francis K. Rengers, Jason W. Kean, Jeffrey A. Coe, Megan Hanson, Joel Smith