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Geodetic measurements of slow slip events southeast of Parkfield, CA

Tremor and low-frequency earthquakes are presumed to be indicative of surrounding slow, aseismic slip that is often below geodetic detection thresholds. This study uses data from borehole seismometers and long-baseline laser strainmeters to observe both the seismic and geodetic signatures of episodic tremor and slip on the Parkfield region of the San Andreas Fault near Cholame, CA. The observed oc
Authors
Brent G. Delbridge, Joshua D. Carmichael, Robert M. Nadeau, David R. Shelly, Roland Burgmann

Operational earthquake forecasting during the 2019 Ridgecrest, California, earthquake sequence with the UCERF3-ETAS model

The first Uniform California Earthquake Rupture Forecast, Version 3–epidemic‐type aftershock sequence (UCERF3‐ETAS) aftershock simulations were running on a high‐performance computing cluster within 33 min of the 4 July 2019 M 6.4 Searles Valley earthquake. UCERF3‐ETAS, an extension of the third Uniform California Earthquake Rupture Forecast (UCERF3), is the first comprehensive, fault‐based, epide
Authors
Kevin R. Milner, Edward H. Field, William H Savran, Morgan T. Page, Thomas H Jordan

Planetary sensor models interoperability using the community sensor model specification

This paper presents the photogrammetric foundations upon which the Community Sensor Model specification depends, describes common coordinate system and reference frame transformations that support conversion between image sensor (charge‐coupled device) coordinates to some arbitrary body coordinate, and describes the U.S. Geological Survey Astrogeology Community Sensor Model implementation (https:/
Authors
Jason Laura, Jesse Mapel, Trent M. Hare

A machine learning approach to developing ground motion models from simulated ground motions

We use a machine learning approach to build a ground motion model (GMM) from a synthetic database of ground motions extracted from the Southern California CyberShake study. An artificial neural network is used to find the optimal weights that best fit the target data (without overfitting), with input parameters chosen to match that of state-of-the-art GMMs. We validate our synthetic-based GMM with
Authors
Kyle Withers, Morgan P. Moschetti, Eric M. Thompson

Preparing for geophysical science on the surface of the moon enabled by Artemis

Geophysical methods have been extremely successful in identifying resources on Earth as they provide a means of characterizing and mapping the sub-surface using data gathered on and above the target structures. Geophysics on the Moon will be an important tool for identifying key targets for geological prospecting, scientific sampling, assessing hazards and risks to crew and infrastructure, and det
Authors
Nicholas Schmerr, Jacob A. Richardson, R. Ghent, Matt Seigler, Molly Wasser, Patrick Wheeley, D. Buczkowski, Lynne Carter, Chuck Connor, Laura Connor, Jacob E. Bleacher, M. Fouch, D. Baker, T. Hurford, L. Jozwiak, Sarah Kruse, V. Lekic, A. Naids, Ryan Porter, L. Montesi, Derek Richardson, M. Elise Rumpf, J. Sunshine, Norbert Schorghofer, S. Goossens, Nicole Whelley, D. Wyrick, W. Zhu, Ernie Bell, J. DeMartini, D. Coan, D. Akin, Barbara Cohen, E. Mazarico, Clive Neal, M. Panning, Noah Petro, B. Strauss, Renee Weber, T. Glotch, A. Hendrix, A. Parker, Sarah Wright

Structural control on megathrust rupture and slip behavior: Insights from the 2016 Mw 7.8 Pedernales Ecuador earthquake

The heterogeneous seafloor topography of the Nazca Plate as it enters the Ecuador subduction zone provides an opportunity to document the influence of seafloor roughness on slip behavior and megathrust rupture. The 2016 Mw 7.8 Pedernales Ecuador earthquake was followed by a rich and active postseismic sequence. An internationally coordinated rapid response effort installed a temporary seismic netw
Authors
Lillian Soto-Cordero, Anne Meltzer, Eric A. Bergman, Mariah Hoskins, Joshua C. Stachnik, Hans Agurto-Detzel, Alexandra Alvarado, Susan L. Beck, Philippe Charvis, Yvonne Font, Gavin P. Hayes, Stephen Hernandez, Sergio Leon-Rios, Colton Lynner, Jean-Mathieu Nocquet, Marc Regnier, Andreas Rietbrock, Frederique Rolandone, Mario Ruiz

Mapping metabolic activity at single cell resolution in intact volcanic fumarole soil

Interactions among microorganisms and their mineralogical substrates govern the structure, function, and emergent properties of microbial communities. These interactions are predicated on spatial relationships, which dictate metabolite exchange and access to key substrates. To quantitatively assess links between spatial relationships and metabolic activity, this study presents a novel approach to
Authors
Jeffrey J. Marlow, Isabella Colocci, Sean Jungbluth, Nils Moritz Weber, Amy Gartman, Jens Kallmeyer

The 2019 Ridgecrest, California, earthquake sequence ground motions: Processed records and derived intensity metrics

Following the 2019 Ridgecrest, California, earthquake sequence, we compiled ground‐motion records from multiple data centers and processed these records using newly developed ground‐motion processing software that performs quality assurance checks, performs standard time series processing steps, and computes a wide range of ground‐motion metrics. In addition, we compute station and waveform metric
Authors
John Rekoske, Eric M. Thompson, Morgan P. Moschetti, Mike Hearne, Brad T. Aagaard, Grace Alexandra Parker

A new technique to calculate earthquake stress transfer and to forecast aftershocks

Coseismic stress changes have been the primary physical principle used to explain aftershocks and triggered earthquakes. However, this method does not adequately forecast earthquake rates and diverse rupture populations when subjected to formal testing. We show that earthquake forecasts can be impaired by assumptions made in physics-based models, such as the existence of hypothetical optimal fault
Authors
Margarita Segou, Thomas E. Parsons

Semiautomated estimates of directivity and related source properties of small to moderate southern California earthquakes using second seismic moments

We develop a semiautomated method for estimating with second seismic moments the directivity, rupture area, duration, and centroid velocity of earthquakes. The method is applied to 41 southern California earthquakes with magnitude in the range 3.5–5.2 and provides stable results for 28 events. Apparent source time functions (ASTFs) of P and S phases are derived using deconvolution with three stack
Authors
Haoran Meng, Jeffrey McGuire, Yehuda Ben-Zion

Basin amplification effects in the Puget Lowland, Washington from strong motion recordings and 3D simulations

Sedimentary basins in the Puget Sound region, Washington State, increase ground‐motion intensity and duration of shaking during local earthquakes. We analyze Pacific Northwest Seismic Network and U.S. Geological Survey strong‐motion recordings of five local earthquakes (M 3.9–6.8), including the 2001 Nisqually earthquake, to characterize sedimentary basin effects within the Seattle and Tacoma basi
Authors
Mika Thompson, Erin Wirth, Arthur Frankel, J. Renate Hartog, John E. Vidale

Blind testing of shoreline evolution models

Beaches around the world continuously adjust to daily and seasonal changes in wave and tide conditions, which are themselves changing over longer time-scales. Different approaches to predict multi-year shoreline evolution have been implemented; however, robust and reliable predictions of shoreline evolution are still problematic even in short-term scenarios (shorter than decadal). Here we show res
Authors
Jennifer Montaño, Giovanni Coco, Jose Antolinez, Tomas Beuzen, Karin Bryan, Laura Cagigal, Bruno Castelle, Mark Davidson, Evan B. Goldstein, Raimundo Ibaceta, Déborah Idier, Bonnie C. Ludka, Sina Masoud-Ansari, Fernando Mendez, A. Brad Murray, Nathaniel G. Plant, Katherine Ratlif, Arthur Robinet, Ana Rueda, Nadia Sénéchal, Joshua Simmons, Kristen Splinter, Scott Stephens, Ian Townend, Sean Vitousek, Kilian Vos