Publications
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Mars Reconnaissance Orbiter and Opportunity observations of the Burns formation: crater hopping at Meridiani Planum 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...
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
Revisions to some parameters used in stochastic-method simulations of ground motion 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...
Authors
David Boore, Eric M. Thompson
Real-time validation of the Dst Predictor model 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...
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 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...
Authors
Rex L. Baum, Jason W. Kean
The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes 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...
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. Ferre, 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) 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...
Authors
Gavin P. Hayes, Gregory M. Smoczyk, Harley M. Benz, Kevin P. Furlong, Antonio Villaseñor
Coping with earthquakes induced by fluid injection 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...
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 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...
Authors
Guy R. Gelfenbaum, Andrew W. Stevens, Ian M. Miller, Jonathan A. Warrick, Andrea S. Ogston, Emily Eidam
The 21 May 2014 Mw 5.9 Bay of Bengal earthquake: macroseismic data suggest a high‐stress‐drop event The 21 May 2014 Mw 5.9 Bay of Bengal earthquake: macroseismic data suggest a high‐stress‐drop event
A modest but noteworthy Mw 5.9 earthquake occurred in the Bay of Bengal beneath the central Bengal fan at 21:51 Indian Standard Time (16:21 UTC) on 21 May 2014. Centered over 300 km from the eastern coastline of India (Fig. 1), it caused modest damage by virtue of its location and magnitude. However, shaking was very widely felt in parts of eastern India where earthquakes are uncommon...
Authors
Stacey Martin, Susan E. Hough
Predicting locations of post-fire debris-flow erosionin the San Gabriel Mountains of southern California Predicting locations of post-fire debris-flow erosionin the San Gabriel Mountains of southern California
Timely hazard assessments are needed to assess post-fire debris flows that may impact communities located within and adjacent to recently burned areas. Implementing existing models for debris-flow probability and magnitude can be time-consuming because the geographic extent for applying the models is manually defined. In this study, a model is presented for predicting locations of post...
Authors
Joseph E. Gartner, P.M Santi, Susan H. Cannon
Earthquake hypocenters and focal mechanisms in central Oklahoma reveal a complex system of reactivated subsurface strike-slip faulting Earthquake hypocenters and focal mechanisms in central Oklahoma reveal a complex system of reactivated subsurface strike-slip faulting
The sharp increase in seismicity over a broad region of central Oklahoma has raised concern regarding the source of the activity and its potential hazard to local communities and energy industry infrastructure. Since early 2010, numerous organizations have deployed temporary portable seismic stations in central Oklahoma in order to record the evolving seismicity. In this study, we apply...
Authors
Daniel E. McNamara, Harley M. Benz, Robert B. Herrmann, Eric A. Bergman, Paul S. Earle, Austin F. Holland, Randy W. Baldwin, A. Gassner
Strike-parallel and strike-normal coordinate system around geometrically complicated rupture traces: use by NGA-West2 and further improvements Strike-parallel and strike-normal coordinate system around geometrically complicated rupture traces: use by NGA-West2 and further improvements
We present a two-dimensional system of generalized coordinates for use with geometrically complex fault ruptures that are neither straight nor continuous. The coordinates are a generalization of the conventional strike-normal and strike-parallel coordinates of a single straight fault. The presented conventions and formulations are applicable to a single curved trace, as well as multiple...
Authors
Paul A. Spudich, Brian Chiou