Publications
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High concentrations of manganese and sulfur in deposits on Murray Ridge, Endeavour Crater, Mars
Mars Reconnaissance Orbiter HiRISE images and Opportunity rover observations of the ~22 km wide Noachian age Endeavour Crater on Mars show that the rim and surrounding terrains were densely fractured during the impact crater-forming event. Fractures have also propagated upward into the overlying Burns formation sandstones. Opportunity’s observations show that the western crater rim segment, called
Authors
Raymond E. Arvidson, Steven W. Squyres, Richard V. Morris, Andrew H. Knoll, Ralf Gellert, Benton C. Clark, Jeffrey G. Catalano, Bradley L. Jolliff, Scott M. McLennan, Kenneth E. Herkenhoff, Scott VanBommel, David W. Mittelfehldt, John P. Grotzinger, Edward A. Guinness, Jeffrey R. Johnson, James F. Bell, William H. Farrand, Nathan Stein, Valerie K. Fox, Matthew P. Golombek, Margaret A. G. Hinkle, Wendy M. Calvin, Paulo A. de Souza
Reconsidering earthquake scaling
The relationship (scaling) between scalar moment, M0, and duration, T, potentially provides key constraints on the physics governing fault slip. The prevailing interpretation of M0-T observations proposes different scaling for fast (earthquakes) and slow (mostly aseismic) slip populations and thus fundamentally different driving mechanisms. We show that a single model of slip events within bounded
Authors
Joan S. Gomberg, Aaron G. Wech, Kenneth Creager, K. Obara, Duncan Agnew
Spatial variations in fault friction related to lithology from rupture and afterslip of the 2014 South Napa, California, earthquake
Following earthquakes, faults are often observed to continue slipping aseismically. It has been proposed that this afterslip occurs on parts of the fault with rate-strengthening friction that are stressed by the mainshock, but our understanding has been limited by a lack of immediate, high-resolution observations. Here we show that the behavior of afterslip following the 2014 South Napa earthquake
Authors
Michael Floyd, Richard Walters, John Elliot, Gareth J. Funning, Jerry L. Svarc, Jessica R. Murray, Andy Hooper, Yngvar Larsen, Petar Marinkovic, Roland Bürgmann, Ingrid A. Johanson, Tim Wright
The potential uses of operational earthquake forecasting
This article reports on a workshop held to explore the potential uses of operational earthquake forecasting (OEF). We discuss the current status of OEF in the United States and elsewhere, the types of products that could be generated, the various potential users and uses of OEF, and the need for carefully crafted communication protocols. Although operationalization challenges remain, there was cle
Authors
Edward H. Field, Thomas Jordan, Lucille M. Jones, Andrew Michael, Michael L. Blanpied
Aftershocks of the 2014 South Napa, California, Earthquake: Complex faulting on secondary faults
We investigate the aftershock sequence of the 2014 MW6.0 South Napa, California, earthquake. Low-magnitude aftershocks missing from the network catalog are detected by applying a matched-filter approach to continuous seismic data, with the catalog earthquakes serving as the waveform templates. We measure precise differential arrival times between events, which we use for double-difference event re
Authors
Jeanne L. Hardebeck, David R. Shelly
An automatic P‐Phase arrival‐time picker
Presented is a new approach for picking P‐phase arrival time in single‐component acceleration or broadband velocity records without requiring detection interval or threshold settings. The algorithm PPHASEPICKER transforms the signal into a response domain of a single‐degree‐of‐freedom (SDOF) oscillator with viscous damping and then tracks the rate of change of dissipated damping energy to pick P‐w
Authors
Erol Kalkan
Demonstration of the Cascadia G‐FAST geodetic earthquake early warning system for the Nisqually, Washington, earthquake
A prototype earthquake early warning (EEW) system is currently in development in the Pacific Northwest. We have taken a two‐stage approach to EEW: (1) detection and initial characterization using strong‐motion data with the Earthquake Alarm Systems (ElarmS) seismic early warning package and (2) the triggering of geodetic modeling modules using Global Navigation Satellite Systems data that help pro
Authors
Brendan Crowell, David Schmidt, Paul Bodin, John Vidale, Joan S. Gomberg, J. Renate Hartog, Victor Kress, Tim Melbourne, Marcelo Santillian, Sarah E. Minson, Dylan Jamison
Money matters: Rapid post-earthquake financial decision-making
Post-earthquake financial decision-making is a realm beyond that of many people. In the immediate aftermath of a damaging earthquake, billions of dollars of relief, recovery, and insurance funds are in the balance through new financial instruments that allow those with resources to hedge against disasters and those at risk to limit their earthquake losses and receive funds for response and recover
Authors
David J. Wald, Guillermo Franco
Earthquake outlook for the San Francisco Bay region 2014–2043
Using information from recent earthquakes, improved mapping of active faults, and a new model for estimating earthquake probabilities, the 2014 Working Group on California Earthquake Probabilities updated the 30-year earthquake forecast for California. They concluded that there is a 72 percent probability (or likelihood) of at least one earthquake of magnitude 6.7 or greater striking somewhere in
Authors
Brad T. Aagaard, J. Luke Blair, John Boatwright, Susan H. Garcia, Ruth A. Harris, Andrew J. Michael, David P. Schwartz, Jeanne S. DiLeo
California State Waters Map Series — Monterey Canyon and vicinity, California
IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpre
Authors
Peter Dartnell, Katherine L. Maier, Mercedes D. Erdey, Bryan E. Dieter, Nadine E. Golden, Samuel Y. Johnson, Stephen R. Hartwell, Guy R. Cochrane, Andrew C. Ritchie, David P. Finlayson, Rikk G. Kvitek, Ray W. Sliter, H. Gary Greene, Clifton W. Davenport, Charles A. Endris, Lisa M. Krigsman
The Montaguto earth flow: nine years of observation and analysis
This paper summarizes the methods, results, and interpretation of analyses carried out between 2006 and 2015 at the Montaguto earth flow in southern Italy. We conducted a multi-temporal analysis of earth-flow activity to reconstruct the morphological and structural evolution of the flow. Data from field mapping were combined with a geometric reconstruction of the basal slip surface i
Authors
L. Guerriero, R Revellino, G. Grelle, N Diodato, F.M. Guadagno, Jeffrey A. Coe
The Elizabeth Lake paleoseismic site: Rupture pattern constraints for the past ~800 years for the Mojave section of the south-central San Andreas Fault
The southern San Andreas Fault in California has hosted two historic surface-rupturing earthquakes, the ~M7 1812 Wrightwood earthquake and the ~M7.9 1857 Fort Tejon earthquake (e.g., Sieh, 1978; Jacoby et al., 1988). Numerous paleoseismic studies have established chronologies of historic and prehistoric earthquakes at sites along the full length of the 1857 rupture (e.g., Sieh, 1978; Scharer et al
Authors
Sean Bemis, Katherine M. Scharer, James F. Dolan, Ed Rhodes