Publications
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Simulated effect of topography and soil properties on hydrologic response and landslide potential under variable rainfall conditions in the Oregon Coast Range, USA
No abstract available.
Authors
Benjamin B. Mirus, Joel B. Smith, Jonathan W. Godt, R.L. Baum, Jeffrey A. Coe
Planetary caves’ role in astronaut bases and the search for life
Planetary caves are practically everywhere. Scientists have identified more than 200 lunar and more than 2000 Martian cave-related features. They’ve also found vents and fissures associated with water ice plumes on Saturnian, Jovian, and Neptunian moons. Recently, primary vents of two possible cryovolcanoes were identified on Pluto.
Authors
J. Judson Wynne, Timothy N. Titus, Penelope J. Boston
Episodic bedrock erosion by gully-head migration, Colorado High Plains, USA
This study explores the frequency of bedrock exposure in a soil-mantled low-relief (i.e. non-mountainous) landscape. In the High Plains of eastern Colorado, gully headcuts are among the few erosional features that will incise through the soil mantle to expose bedrock. We measured the last time of bedrock exposure using optically stimulated luminescence dating of alluvial sediment overlying bedrock
Authors
Francis K. Rengers, G.E. Tucker, Shannon Mahan
Updated logistic regression equations for the calculation of post-fire debris-flow likelihood in the western United States
Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can generate dangerous flash floods and debris flows. To reduce public exposure to hazard, the U.S. Geological Survey produces post-fire debris-flow hazard assessments for select fires in the western United States. We use publicly available geospatial data describing basin morphology,
Authors
Dennis M. Staley, Jacquelyn A. Negri, Jason W. Kean, Jayme L. Laber, Anne C. Tillery, Ann M. Youberg
Induced earthquake magnitudes are as large as (statistically) expected
A major question for the hazard posed by injection-induced seismicity is how large induced earthquakes can be. Are their maximum magnitudes determined by injection parameters or by tectonics? Deterministic limits on induced earthquake magnitudes have been proposed based on the size of the reservoir or the volume of fluid injected. However, if induced earthquakes occur on tectonic faults oriented f
Authors
Nicholas van der Elst, Morgan T. Page, Deborah A. Weiser, Thomas Goebel, S. Mehran Hosseini
Ground motions at the outermost limits of seismically triggered landslides
Over the last few decades, we and our colleagues have conducted field investigations in which we mapped the outermost limits of triggered landslides in four earthquakes: 1987 Whittier Narrows, California (M 5.9), 1987 Superstition Hills, California (M 6.5), 1994 Northridge, California (M 6.7), and 2011 Mineral, Virginia (M 5.8). In an additional two earthquakes, 1976 Guatemala (M 7.5) and 1983 Coa
Authors
Randall W. Jibson, Edwin L. Harp
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