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Publications

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Does earthquake stress drop increase with depth in the crust?

We combine earthquake spectra from multiple studies to investigate whether the increase in stress drop with depth often observed in the crust is real, or an artifact of decreasing attenuation (increasing Q) with depth. In many studies, empirical path and attenuation corrections are assumed to be independent of the earthquake source depth. We test this assumption by investigating whether a realisti
Authors
Rachel E Abercrombie, Daniel T. Trugman, Peter M. Shearer, Xiaowei Chen, Jiewen Zhang, Colin Nathanael Pennington, Jeanne L. Hardebeck, Thomas H W Goebel, Christine J Ruhl

A preliminary regional geomorphologic map in Utopia Planitia of the Tianwen-1 Zhurong Landing Region

A geomorphologic map is an important step to understanding the geologic context and history of a site; here, we present an initial geomorphologic map for an area spanning 22°–26°N, 108°–112°E in the Utopia Planitia (UP) region on Mars. This site is of special interest because it contains the May 2021 landing site of the Zhurong rover from Tianwen-1. Utopia Planitia exhibits many lobate features th
Authors
Mackenzie M Mills, Alfred S. McEwen, Chris Okubo

The 6 May 1947 Milwaukee, Wisconsin, earthquake

The State of Wisconsin is not known for earthquake activity. The authoritative public‐facing U.S. Geological Survey Comprehensive Catalog of earthquakes includes only three small (magnitude < 2) earthquakes in the state, all instrumentally recorded. Although other catalogs include more events in Wisconsin, experience has shown that many types of events, such as explosions and cryoseisms, have made
Authors
Susan E. Hough

Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS)

We describe recent improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS), which continues to represent our most advanced and complete earthquake forecast in terms of relaxing segmentation assumptions and representing multifault ruptures, elastic‐rebound effects, and spatiotemporal clustering (the latter to represent aftershocks and otherwise triggered ev
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page, William H. Savran, Nicholas van der Elst

Advancing cave detection using terrain analysis and thermal imagery

Since the initial experiments nearly 50 years ago, techniques for detecting caves using airborne and spacecraft acquired thermal imagery have improved markedly. These advances are largely due to a combination of higher instrument sensitivity, modern computing systems, and processor-intensive analytical techniques. Through applying these advancements, our goals were to: (1) Determine the efficacy o
Authors
J. Judson Wynne, Jeff Jenness, Derek Sonderegger, Timothy N. Titus, Murzy D. Jhabvala, Nathalie A. Cabrol

Effect of fixing earthquake depth in ShakeAlert algorithms on performance for intraslab earthquakes

We investigate whether assuming a fixed shallow depth in the ShakeAlert network‐based earthquake early warning system is sufficient to produce accurate ground‐motion based alerts for intraslab earthquakes. ShakeAlert currently uses a fixed focal depth of 8 km to estimate earthquake location and magnitude. This is an appropriate way to reduce computational costs without compromising alert accuracy
Authors
Mika Thompson, J. Renate Hartog, Erin Wirth

Rigorously valuing the coastal hazard risks reduction provided by potential coral reef restoration in Florida and Puerto Rico

The restoration of coastal habitats, particularly coral reefs, can reduce risks by decreasing the exposure of coastal communities to flooding hazards. In the United States, the protective services provided by coral reefs were recently assessed in social and economic terms, with the annual protection provided by U.S. coral reefs off the coasts of the State of Florida and the Commonwealth of Puerto
Authors
Curt D. Storlazzi, Borja G. Reguero, Kristen A. Cumming, Aaron Cole, James B. Shope, Camila Gaido L., T. Shay Viehman, Barry A. Nickel, Michael W. Beck

Rigorously valuing the impact of projected coral reef degradation on coastal hazard risk in Florida

The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards. In the United States, the physical protective services provided by coral reefs were recently assessed, in social and economic terms, with the annual protection provided by U.S. coral reefs off the coast of the State of Florida estimated to be more than
Authors
Curt D. Storlazzi, Borja G. Reguero, Kimberly K. Yates, Kristen A. Cumming, Aaron Cole, James B. Shope, Camila Gaido L., David G. Zawada, Stephanie R. Arsenault, Zachery W. Fehr, Barry A. Nickel, Michael W. Beck

Rigorously valuing the impact of Hurricanes Irma and Maria on coastal hazard risks in Florida and Puerto Rico

The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards. In the United States, the physical protective services provided by coral reefs were recently assessed in social and economic terms, with the annual protection provided by U.S. coral reefs off the coasts of the State of Florida and the Commonwealth of Pu
Authors
Curt D. Storlazzi, Borja G. Reguero, T. Shay Viehman, Kristen A. Cumming, Aaron Cole, James B. Shope, Sarah H. Groves, Camila Gaido L., Barry A. Nickel, Michael W. Beck

Reinterpreting the Bruun Rule in the context of equilibrium shoreline models

Long-term (>decades) coastal recession due to sea-level rise (SLR) has been estimated using the Bruun Rule for nearly six decades. Equilibrium-based shoreline models have been shown to skillfully predict short-term wave-driven shoreline change on time scales of hours to decades. Both the Bruun Rule and equilibrium shoreline models rely on the equilibrium beach theory, which states that the beach p
Authors
Maurizio D'Anna, Deborah Idier, Bruno Castelle, Sean Vitousek, Goneri Le Cozannet

Evaluating stereo digital terrain model quality at Mars Rover Landing Sites with HRSC, CTX, and HiRISE Images

We have used high-resolution digital terrain models (DTMs) of two rover landing sites based on mosaicked images from the High-Resolution Imaging Science Experiment (HiRISE) camera as a reference to evaluate DTMs based on High-Resolution Stereo Camera (HRSC) and Context Camera (CTX) images. The Next-Generation Automatic Terrain Extraction (NGATE) matcher in the SOCET SET and GXP® commercial photogr
Authors
Randolph L. Kirk, David Mayer, Robin L. Fergason, Bonnie L. Redding, Donna M. Galuszka, Trent M. Hare, Klaus Gwinner

Watershed sediment yield following the 2018 Carr Fire, Whiskeytown National Recreation Area, northern California

Wildfire risk has increased in recent decades over many regions, due to warming climate and other factors. Increased sediment export from recently burned landscapes can jeopardize downstream infrastructure and water resources, but physical landscape response to fire has not been quantified for some at-risk areas, including much of northern California, USA. We measured sediment yield from three wat
Authors
Amy E. East, Joshua B. Logan, Peter Dartnell, Oren Lieber-Kotz, David B. Cavagnaro, Scott W. McCoy, Donald N. Lindsay