Publications
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Changes in permeability caused by transient stresses: field observations, experiments, and mechanisms
Oscillations in stress, such as those created by earthquakes, can increase permeability and fluid mobility in geologic media. In natural systems, strain amplitudes as small as 10–6 can increase discharge in streams and springs, change the water level in wells, and enhance production from petroleum reservoirs. Enhanced permeability typically recovers to prestimulated values over a period of months
Authors
Michael Manga, Igor Beresnev, Emily E. Brodsky, Jean E. Elkhoury, Derek Elsworth, Steve E. Ingebritsen, David C. Mays, Chi-Yuen Wang
Sediment entrainment by debris flows: In situ measurements from the headwaters of a steep catchment
Debris flows can dramatically increase their volume, and hence their destructive potential, by entraining sediment. Yet quantitative constraints on rates and mechanics of sediment entrainment by debris flows are limited. Using an in situ sensor network in the headwaters of a natural catchment we measured flow and bed properties during six erosive debris-flow events. Despite similar flow properties
Authors
S.W. McCoy, Jason W. Kean, Jeffrey A. Coe, G.E. Tucker, Dennis M. Staley, T.A. Wasklewicz
Helping safeguard Veterans Affairs' hospital buildings by advanced earthquake monitoring
In collaboration with the U.S. Department of Veterans Affairs (VA), the National Strong Motion Project of the U.S. Geological Survey has recently installed sophisticated seismic systems that will monitor the structural integrity of hospital buildings during earthquake shaking. The new systems have been installed at more than 20 VA medical campuses across the country. These monitoring systems, whic
Authors
Erol Kalkan, Krishna Banga, Hasan S. Ulusoy, Jon Peter B. Fletcher, William S. Leith, James L. Blair
Turbidite event history—Methods and implications for Holocene paleoseismicity of the Cascadia subduction zone
Turbidite systems along the continental margin of Cascadia Basin from Vancouver Island, Canada, to Cape Mendocino, California, United States, have been investigated with swath bathymetry; newly collected and archive piston, gravity, kasten, and box cores; and accelerator mass spectrometry radiocarbon dates. The purpose of this study is to test the applicability of the Holocene turbidite record as
Authors
Chris Goldfinger, C. Hans Nelson, Ann E. Morey, Joel E. Johnson, Jason R. Patton, Eugene B. Karabanov, Julia Gutierrez-Pastor, Andrew T. Eriksson, Eulalia Gracia, Gita Dunhill, Randolph J. Enkin, Audrey Dallimore, Tracy Vallier
Initial assessment of the intensity distribution of the 2011 Mw5.8 Mineral, Virginia, earthquake
The intensity data collected by the U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) Website (USGS, DYFI; http://earthquake.usgs.gov/earthquakes/dyfi/events/se/082311a/us/index.html, last accessed Sept 2011) for the Mw5.8 Mineral, Virginia, earthquake, are unprecedented in their spatial richness and geographical extent. More than 133,000 responses were received during the first week followi
Authors
Susan E. Hough
Publication: Evansville hazard maps
The Evansville (Indiana) Area Earthquake Hazards Mapping Project was completed in February 2012. It was a collaborative effort among the U.S. Geological Survey and regional partners Purdue University; the Center for Earthquake Research and Information at the University of Memphis; the state geologic surveys of Kentucky, Illinois, and Indiana; the Southwest Indiana Disaster Resistant Community Corp
Authors
Refinements to the method of epicentral location based on surface waves from ambient seismic noise: introducing Love waves
The purpose of this study is to develop and test a modification to a previous method of regional seismic event location based on Empirical Green’s Functions (EGFs) produced from ambient seismic noise. Elastic EGFs between pairs of seismic stations are determined by cross-correlating long ambient noise time-series recorded at the two stations. The EGFs principally contain Rayleigh- and Love-wave ene
Authors
Anatoli L. Levshin, Mikhail P. Barmin, Morgan P. Moschetti, Carlos Mendoza, Michael H. Ritzwoller
Objective definition of rainfall intensity-duration thresholds for the initiation of post-fire debris flows in southern California
Rainfall intensity–duration (ID) thresholds are commonly used to predict the temporal occurrence of debris flows and shallow landslides. Typically, thresholds are subjectively defined as the upper limit of peak rainstorm intensities that do not produce debris flows and landslides, or as the lower limit of peak rainstorm intensities that initiate debris flows and landslides. In addition, peak rains
Authors
Dennis Staley, Jason W. Kean, Susan H. Cannon, Kevin M. Schmidt, Jayme L. Laber
Fault populations
No abstract available.
Authors
Richard A. Schultz, Roger Soliva, Chris Okubo, Daniel Mège
The new IASPEI standards for determining magnitudes from digital data and their relation to classical magnitudes
Why there is a need for measurement standards of magnitudes:
In October 2005, the Commission on Seismic Observation and Interpretation of the
International Association of Seismology and Physics of the Earth´s Interior (IASPEI) adopted
the summary recommendations made by the IASPEI Working Group on Magnitudes on new
measurement standards for widely used local, regional and teleseismic magnitude sc
Authors
Peter Bormann, James W. Dewey
Source parameters of microearthquakes on an interplate asperity off Kamaishi, NE Japan over two earthquake cycles
We have estimated the source parameters of interplate earthquakes in an earthquake cluster off Kamaishi, NE Japan over two cycles of M~ 4.9 repeating earthquakes. The M~ 4.9 earthquake sequence is composed of nine events that occurred since 1957 which have a strong periodicity (5.5 ± 0.7 yr) and constant size (M4.9 ± 0.2), probably due to stable sliding around the source area (asperity). Using P-
Authors
Naoki Uchida, Toru Matsuzawa, William L. Ellsworth, Kazutoshi Imanishi, Kouhei Shimamura, Akira Hasegawa
Erratum: regional moisture balance control of landslide motion: implications for landslide forecasting in a changing climate
No abstract available.
Authors
Jeffrey A. Coe