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Publications

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Earth’s upper crust seismically excited by infrasound from the 2022 Hunga Tonga–Hunga Ha’apai eruption, Tonga

Records of pressure variations on seismographs were historically considered unwanted noise; however, increased deployments of collocated seismic and acoustic instrumentation have driven recent efforts to use this effect induced by both wind and anthropogenic explosions to invert for near‐surface Earth structure. These studies have been limited to shallow structure because the pressure signals have
Authors
Robert E. Anthony, Adam T. Ringler, Toshiro Tanimoto, Robin Matoza, Silvio De Angelis, David C. Wilson

Defining the Hoek-Brown constant mi for volcanic lithologies

The empirical Hoek-Brown failure criterion is a well-known and commonly used failure criterion for both intact rocks and rock masses, especially in geological engineering. The intact criterion is calculated using experimental triaxial compression test results on intact samples while the rock mass criterion modifies the intact strength using quantified measures of the rock mass quality. The Hoek-Br
Authors
Marlène C. Villeneuve, Michael J. Heap, Lauren N. Schaefer

Giant planet observations in NASA's Planetary Data System

While there have been far fewer missions to the outer Solar System than to the inner Solar System, spacecraft destined for the giant planets have conducted a wide range of fundamental investigations, returning data that continues to reshape our understanding of these complex systems, sometimes decades after the data were acquired. These data are preserved and accessible from national and internati
Authors
Nancy J. Chanover, James M. Bauer, John Joe Jeremiah Blalock, Mitchell K. Gordon, Lyle F. Huber, Mia J. T. Mace, Lynn D. V. Neakrase, Matthew S. Tiscareno, Raymond J. Walker

COSMOS Ground-Motion Simulation Working Group workshops #1 and #2

These 2 workshops were held in response to interest generated from sessions on the use of simulated earthquake ground motions at the 2020 and 2021 Consortium of Organizations for Strong Motion Observation Systems (COSMOS) Technical Sessions. The discussions at the Technical Sessions highlighted desires to promote the use of simulated earthquake ground motions for engineering applications and the n
Authors
Brad T. Aagaard, Aysegul Askan, Sanaz Rezaeian, Sean Kamran Ahdi, Alan Yong

Using a grid-search approach to validate the Graves-Pitarka broadband simulation method

This work assesses the ability of the Graves–Pitarka simulation approach to reproduce observed ground motions for 12 California and Baja California earthquakes. A total of 240 realizations are computed for each earthquake and compared with recorded strong motions from near-fault sites. In addition to spatial variability in slip, each realization samples from discrete combinations of average ruptur
Authors
Robert Graves

The cycles driving Io’s tectonics

Io is famous for its active volcanoes, but its vigorous tectonics, which are unlike Earth’s plate tectonics, are no less remarkable. The nature of Io’s thick, cold, brittle lithosphere has been revealed through decades of investigations. The dynamics of this system is most easily explained by considering three cycles: magmatic, tectonic, and sulfurous. The magmatic cycle transports heat by a “heat
Authors
Laszlo P. Kestay, Windy L Jaeger, Jani Radebaugh

OpenET: Filling a critical data gap in water management for the western United States

The lack of consistent, accurate information on evapotranspiration (ET) and consumptive use of water by irrigated agriculture is one of the most important data gaps for water managers in the western United States (U.S.) and other arid agricultural regions globally. The ability to easily access information on ET is central to improving water budgets across the West, advancing the use of data-driven
Authors
Forrest Melton, Justin Huntington, Robyn Grimm, Jamie Herring, Maurice Hall, Dana Rollison, Tyler Erickson, Richard Allen, Martha Anderson, Joshua Fisher, Ayse Kilic, Gabriel Senay, John Volk, Christopher Hain, Lee Johnson, Anderson Ruhoff, Philip Blankenau, Matthew Bromley, Will Carrara, Britta Daudert, Conor Doherty, Christian Dunkerly, MacKenzie Friedrichs, Alberto Guzman, Gregory Halverson, Jody Hansen, Jordan Harding, Yanghui Kang, David C. Ketchum, Blake Minor, Charles Morton, Samuel Ortega-Salazar, Thomas Ott, Mutlu Ozdogan, Peter Revelle, Mitch Schull, Carlos Wang, Yun Yang, Ray G. Anderson

Hybrid broadband ground-motion simulation validation of small magnitude active shallow crustal earthquakes in New Zealand

This article presents a comprehensive validation of the hybrid broadband ground-motion simulation approach (via the commonly used Graves and Pitarka method) in a New Zealand context with small magnitude point source ruptures using an extensive set of 5218 ground motions recorded at 212 sites from 479 active shallow crustal earthquakes across the country. Modifications to the simulation method infe
Authors
Robin L. Lee, Brendon A. Bradley, Peter J. Stafford, Robert Graves, Adrian Rodriguez-Marek

Porosity, strength, and alteration – Towards a new volcano stability assessment tool using VNIR-SWIR reflectance spectroscopy

Volcano slope stability analysis is a critical component of volcanic hazard assessments and monitoring. However, traditional methods for assessing rock strength require physical samples of rock which may be difficult to obtain or characterize in bulk. Here, visible to shortwave infrared (350–2500 nm; VNIR–SWIR) reflected light spectroscopy on laboratory-tested rock samples from Ruapehu, Ohakuri, W
Authors
Gabor Kereszturi, Michael J. Heap, Lauren N. Schaefer, Herlan Darmawan, Frances M. Deegan, Ben M. Kennedy, Jean-Christophe Komorowski, Stuart Mead, Marina Rosas-Carbajal, Amy Ryan, Valentin R. Troll, Marlène C. Villeneuve, Thomas R. Walter

Regional-scale mapping of landscape response to extreme precipitation using repeat lidar and object-based image analysis

Extreme precipitation events may cause flooding, slope failure, erosion, deposition, and damage to infrastructure over a regional scale, but the impacts of these events are often difficult to fully characterize. Regional-scale landscape change occurred during an extreme rain event in June 2012 in northeastern Minnesota. Landscape change was documented by 8,000 km2 of airborne lidar data collected
Authors
Stephen B. DeLong, Morena N Hammer, Zachary T. Engle, Emilie Richard, Andrew Breckenridge, Karen B. Gran, Carrie E. Jennings, Andre Jalobeanu

Violent groundwater eruption triggered by a distant earthquake

It is now well established that earthquakes cause various hydrogeological responses at distances thousands of kilometers from the epicenter. What remains unexplained is the large amplitude and intensity of some responses. Following the 2004 Mw 9.1 Sumatra earthquake, groundwater 3,200 km from the epicenter erupted violently from a well and formed a water fountain reaching a height exceeding 60 m.
Authors
Xin Yan, Zheming Shi, Chi-Yuen Wang, Steven E. Ingebritsen, Michael Manga

High‐precision characterization of seismicity from the 2022 Hunga Tonga‐Hunga Ha'apai volcanic eruption

The earthquake swarm accompanying the January 2022 Hunga Tonga‐Hunga Ha'apai (HTHH) volcanic eruption includes a large number of posteruptive moderate‐magnitude seismic events and presents a unique opportunity to use remote monitoring methods to characterize and compare seismic activity with other historical caldera‐forming eruptions. We compute improved epicentroid locations, magnitudes, and regi
Authors
Jonas A. Kintner, William L. Yeck, Paul S. Earle, Stephanie Prejean, Jeremy Pesicek