Publications
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Quaternary tephrochronology and deposition in the subsurface Sacramento–San Joaquin Delta, California, U.S.A.
We document characteristics of tephra, including facies and geochemistry, from 27 subsurface sites in the Sacramento-San Joaquin Delta, California, to obtain stratigraphic constraints in a complex setting. Analyzed discrete tephra deposits are correlative with: 1) an unnamed tephra from the Carlotta Formation near Ferndale, California, herein informally named the ash of Wildcat Grade (<~1.450 - >~
Authors
Katherine L. Maier, Emma Gatti, Elmira Wan, Daniel J. Ponti, Mark Pagenkopp, Scott W. Starratt, Holly A. Olson, John Tinsley
Long‐term time‐dependent probabilities for the third Uniform California Earthquake Rupture Forecast (UCERF3)
The 2014 Working Group on California Earthquake Probabilities (WGCEP 2014) presents time-dependent earthquake probabilities for the third Uniform California Earthquake Rupture Forecast (UCERF3). Building on the UCERF3 time-independent model, published previously, renewal models are utilized to represent elastic-rebound-implied probabilities. A new methodology has been developed that solves applica
Authors
Edward H. Field, Glenn P. Biasi, Peter Bird, Timothy E. Dawson, Karen R. Felzer, David A. Jackson, Kaj M. Johnson, Thomas H. Jordan, Christopher Madden, Andrew J. Michael, Kevin Milner, Morgan T. Page, Thomas E. Parsons, Peter Powers, Bruce E. Shaw, Wayne R. Thatcher, Ray J. Weldon, Yuehua Zeng
Mars Reconnaissance Orbiter and Opportunity observations of the Burns formation: crater hopping at Meridiani Planum
Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral (1.0–2.65 µm) along-track oversampled observations covering Victoria, Santa Maria, Endeavour, and Ada craters were processed to 6 m/pixel and used in combination with Opportunity observations to detect and map hydrated Mg and Ca sulfate minerals in the Burns formation. The strongest spectral absorption features were found to be ass
Authors
R.E. Arvidson, J.F. Bell, J.G. Catalano, B. C. Clark, V.K. Fox, Ralf Gellert, J.P. Grotzinger, E.A. Guinness, Kenneth E. Herkenhoff, A.H. Knoll, M.G.A. Lapotre, S. M. McLennan, D. W. Ming, R.V. Morris, S.L. Murchie, K. E. Powell, M. D. Smith, S. W. Squyres, M.J. Wolff, J.J. Wray
The Red Atrapa Sismos (Quake Catcher Network in Mexico): assessing performance during large and damaging earthquakes.
The Quake‐Catcher Network (QCN) is an expanding seismic array made possible by thousands of participants who volunteered time and resources from their computers to record seismic data using low‐cost accelerometers (http://qcn.stanford.edu/; last accessed December 2014). Sensors based on Micro‐Electromechanical Systems (MEMS) technology have rapidly improved over the last few years due to the deman
Authors
Luis A. Dominguez, Battalgazi Yildirim, Allen L. Husker, Elizabeth S. Cochran, Carl Christensen, Victor M. Cruz-Atienza
Revisions to some parameters used in stochastic-method simulations of ground motion
The stochastic method of ground‐motion simulation specifies the amplitude spectrum as a function of magnitude (M) and distance (R). The manner in which the amplitude spectrum varies with M and R depends on physical‐based parameters that are often constrained by recorded motions for a particular region (e.g., stress parameter, geometrical spreading, quality factor, and crustal amplifications), whic
Authors
David Boore, Eric M. Thompson
Hydroclimatic conditions preceding the March 2014 Oso landslide
The 22 March 2014 Oso landslide was one of the deadliest in U.S. history, resulting in 43 fatalities and the destruction of more than 40 structures. We examine synoptic conditions, precipitation records and soil moisture reconstructions in the days, months, and years preceding the landslide. Atmospheric reanalysis shows a period of enhanced moisture transport to the Pacific Northwest beginning on
Authors
Brian Henn, Qian Cao, Dennis P. Lettenmaier, Christopher S. Magirl, Clifford Mass, J. Brent Bower, Michael St. Laurent, Yixin Mao, Sanja Perica
Real-time validation of the Dst Predictor model
The Dst Predictor model, which has been running real-time in the Space Weather Analysis and Forecast System (SWAFS), provides 1-hour and 4-hour forecasts of the Dst index. This is useful for awareness of impending geomagnetic activity, as well as driving other real-time models that use Dst as an input. In this report, we examine the performance of this forecast model in detail. When validating ind
Authors
James P. McCollough, Shawn L. Young, E. Joshua Rigler, Hal A. Simpson
Landslide modeling and forecasting—recent progress by the u.s. geological survey
Landslide studies by the U.S. Geological Survey (USGS) are focused on two main objectives: scientific understanding and forecasting. The first objective is to gain better understanding of the physical processes involved in landslide initiation and movement. This objective is largely in support of the second objective, to develop predictive capabilities to answer the main hazard questions. Answers
Authors
Rex L. Baum, Jason W. Kean
The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes
Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these signific
Authors
Luke A. Pangle, Stephen B. DeLong, Nate Abramson, John Adams, Greg A. Barron-Gafford, David D. Breshears, Paul D. Brooks, Jon Chorover, William E. Dietrich, Katerina Dontsova, Matej Durcik, Javier Espeleta, T.P.A. Ferré, Regis Ferriere, Whitney Henderson, Edward A. Hunt, Travis E. Huxman, David Millar, Brendan Murphy, Guo-Yue Niu, Mitch Pavao-Zuckerman, Jon D. Pelletier, Craig Rasmussen, Joaquin Ruiz, Scott Saleska, Marcel Schaap, Michael Sibayan, Peter A. Troch, Markus Tuller, Joost van Haren, Xubin Zeng
Seismicity of the Earth 1900-2013, seismotectonics of South America (Nazca Plate Region)
The South American arc extends over 7,000 kilometers (km), from the Chilean margin triple junction offshore of southern Chile, to its intersection with the Panama fracture zone, offshore of the southern coast of Panama in Central America. It marks the plate boundary between the subducting Nazca plate and the South America plate, where the oceanic crust and lithosphere of the Nazca plate begin thei
Authors
Gavin P. Hayes, Gregory M. Smoczyk, Harley M. Benz, Kevin P. Furlong, Antonio Villaseñor
Coping with earthquakes induced by fluid injection
Large areas of the United States long considered geologically stable with little or no detected seismicity have recently become seismically active. The increase in earthquake activity began in the mid-continent starting in 2001 (1) and has continued to rise. In 2014, the rate of occurrence of earthquakes with magnitudes (M) of 3 and greater in Oklahoma exceeded that in California (see the figure).
Authors
Arthur F. McGarr, Barbara Bekins, Nina Burkardt, James W. Dewey, Paul S. Earle, William L. Ellsworth, Shemin Ge, Stephen H. Hickman, Austin F. Holland, Ernest Majer, Justin L. Rubinstein, Anne Sheehan
Large-scale dam removal on the Elwha River, Washington, USA: coastal geomorphic change
Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of mud, sand, and gravel since 1927, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams, initiated in September 2011, induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the geomo
Authors
Guy R. Gelfenbaum, Andrew W. Stevens, Ian M. Miller, Jonathan A. Warrick, Andrea S. Ogston, Emily Eidam