Publications
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Flood-frequency analyses from paleoflood investigations for Spring, Rapid, Boxelder, and Elk Creeks, Black Hills, western South Dakota
Flood-frequency analyses for the Black Hills area are important because of severe flooding of June 9-10, 1972, that was caused by a large mesoscale convective system and caused at least 238 deaths. Many 1972 peak flows are high outliers (by factors of 10 or more) in observed records that date to the early 1900s. An efficient means of reducing uncertainties for flood recurrence is to augment gaged
Authors
Tessa M. Harden, Jim E. O'Connor, Daniel G. Driscoll, John F. Stamm
Observations of debris flows at Chalk Cliffs, Colorado, USA: Part 1, in-situ measurements of flow dynamics, tracer particle movement and video imagery from the summer of 2009
Debris flows initiated by surface-water runoff during short duration, moderate- to high-intensity rainfall are common in steep, rocky, and sparsely vegetated terrain. Yet large uncertainties remain about the potential for a flow to grow through entrainment of loose debris, which make formulation of accurate mechanical models of debris-flow routing difficult. Using a combination of in situ measurem
Authors
Scott W. McCoy, Jeffrey A. Coe, Jason W. Kean, Greg E. Tucker, Dennis M. Staley, Thad A. Wasklewicz
Transient surface liquid in Titan's south polar region from Cassini
Cassini RADAR images of Titan’s south polar region acquired during southern summer contain lake features which disappear between observations. These features show a tenfold increases in backscatter cross-section between images acquired one year apart, which is inconsistent with common scattering models without invoking temporal variability. The morphologic boundaries are transient, further support
Authors
A. G. Hayes, O. Aharonson, J. I. Lunine, R. L. Kirk, H. A. Zebker, L. C. Wye, R. D. Lorenz, E. P. Turtle, P. Paillou, Giuseppe Mitri, S. D. Wall, E. R. Stofan, K. L. Mitchell, C. Elachi
Liquefaction hazard for the region of Evansville, Indiana
We calculated liquefaction potential index for a grid of sites in the Evansville, Indiana area for two scenario earthquakes-a magnitude 7.7 in the New Madrid seismic zone and a M6.8 in the Wabash Valley seismic zone. For the latter event, peak ground accelerations range from 0.13 gravity to 0.81 gravity, sufficiently high to be of concern for liquefaction.
Recently acquired cone-penetrometer test
Authors
Jennifer S. Haase, Yoon S. Choi, Robert L. Nowack, Chris H. Cramer, Oliver S. Boyd, Robert A. Bauer
Site-specific seismic-hazard maps and deaggregation in the western United States using the NGA models for ground-motion prediction
The 2008 National Seismic Hazard Mapping Project (NSHMP) update for the conterminous United States employs several new ground-motion prediction equations which include modern empirical models of linear and nonlinear site response to local and regional earthquakes. The recent availability of attenuation functions incorporating site conditions via Vs30 values permits the calculation of site-specific
Authors
Stephen Harmsen
A reevaluation of the Munson-Nygren-Retriever submarine landslide complex, Georges bank lower slope, western north Atlantic
The Munson-Nygren-Retriever (MNR) landslide complex is a series of distinct submarine landslides located between Nygren and Powell canyons on the Georges Bank lower slope. These landslides were first imaged in 1978 using widely-spaced seismic reflection profiles and were further investigated using continuous coverage GLORIA sidescan imagery collected over the landslide complex in 1987. Recent acqu
Authors
Jason D. Chaytor, David C. Twichell, Uri S. ten Brink
Seismic zonation of Port-Au-Prince using pixel- and object-based imaging analysis methods on ASTER GDEM
We report about a preliminary study to evaluate the use of semi-automated imaging analysis of remotely-sensed DEM and field geophysical measurements to develop a seismic-zonation map of Port-au-Prince, Haiti. For in situ data, VS30 values are derived from the MASW technique deployed in and around the city. For satellite imagery, we use an ASTER GDEM of Hispaniola. We apply both pixel- and object-b
Authors
Alan Yong, Susan E. Hough, Brady R. Cox, Ellen M. Rathje, Jeff Bachhuber, Ranon Dulberg, David Hulslander, Lisa Christiansen, Michael J. Abrams
Massive CO2 ice deposits sequestered in the south polar layered deposits of Mars
Shallow Radar soundings from the Mars Reconnaissance Orbiter reveal a buried deposit of carbon dioxide (CO2) ice within the south polar layered deposits of Mars with a volume of 9500 to 12,500 cubic kilometers, about 30 times that previously estimated for the south pole residual cap. The deposit occurs within a stratigraphic unit that is uniquely marked by collapse features and other evidence of i
Authors
Roger J. Phillips, Brian J. Davis, Kenneth L. Tanaka, Shane Byrne, Michael T. Mellon, Nathaniel E. Putzig, Robert M. Haberle, Melinda A. Kahre, Bruce A. Campbell, Lynn M. Carter, Isaac B. Smith, John W. Holt, Suzanne E. Smrekar, Daniel C. Nunes, Jeffrey J. Plaut, Anthony F. Egan, Timothy N. Titus, Roberto Seu
Estimating seismic site response in Christchurch City (New Zealand) from dense low-cost aftershock arrays
The Mw 7.1 September 2010 Darfield earthquake, New Zealand, produced widespread damage and liquefaction ~40 km from the epicentre in Christchurch city. It was followed by the even more destructive Mw 6.2 February 2011 Christchurch aftershock directly beneath the city’s southern suburbs. Seismic data recorded during the two large events suggest that site effects contributed to the variations in gro
Authors
Anna E. Kaiser, Rafael A. Benites, Angela Chung, A. John Haines, Elizabeth S. Cochran, Bill Fry
Field Reconnaissance Geologic Mapping of the Columbia Hills, Mars: Results from MER Spirit and MRO HiRISE Observations
Chemical, mineralogic, and lithologic ground truth was acquired for the first time on Mars in terrain units mapped using orbital Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (MRO HiRISE) image data. Examination of several dozen outcrops shows that Mars is geologically complex at meter length scales, the record of its geologic history is well exposed, stratigraphic units
Authors
L.S. Crumpler, R. E. Arvidson, S. W. Squyres, T. McCoy, A. Yingst, S. Ruff, W. Farrand, Y. McSween, M. Powell, D. W. Ming, R.V. Morris, J.F. Bell, J. Grant, R. Greeley, D. DesMarais, M. Schmidt, N.A. Cabrol, A. Haldemann, Kevin W. Lewis, A.E. Wang, C. Schroder, D. Blaney, B. Cohen, A. Yen, J. Farmer, Ralf Gellert, E.A. Guinness, K. E. Herkenhoff, J. R. Johnson, G. Klingelhofer, A. McEwen, J. W. Rice, M. Rice, P. deSouza, J. Hurowitz
Map of debris flows caused by rainfall during 1996 in parts of the Reedsport and Deer Head Point quadrangles, Douglas County, southern Coast Range, Oregon
This 1:12,000-scale map shows an inventory of debris flows caused by rainfall during 1996 in a 94.4 km2 area in the southern Coast Range of Oregon. This map and associated digital data are part of a larger U.S. Geological Survey study of debris flows in the southern Coast Range. Available evidence indicates that the flows were triggered by a rain storm that occurred between November 17 and 19. The
Authors
Jeffrey A. Coe, John A. Michael, Marianela Mercado Burgos
Human casualties in earthquakes: Modelling and mitigation
Earthquake risk modelling is needed for the planning of post-event emergency operations, for the development of insurance schemes, for the planning of mitigation measures in the existing building stock, and for the development of appropriate building regulations; in all of these applications estimates of casualty numbers are essential. But there are many questions about casualty estimation which a
Authors
R.J.S. Spence, E.K.M. So