Publications
Filter Total Items: 7487
Geology of the MER 2003 "Elysium" candidate landing site in southeastern Utopia Planitia, Mars Geology of the MER 2003 "Elysium" candidate landing site in southeastern Utopia Planitia, Mars
The NASA Mars Exploration Rover (MER) Project has been considering a landing-site ellipse designated EP78B2 in southeastern Utopia Planitia, southwest of Elysium Mons. The site appears to be relatively safe for a MER landing site because of its predicted low wind velocities in mesoscale atmospheric circulation models and its low surface roughness at various scales as indicated by...
Authors
Kenneth L. Tanaka, Michael H. Carr, James A. Skinner, Martha S. Gilmore, Trent M. Hare
Debris-flow initiation from large, slow-moving landslides Debris-flow initiation from large, slow-moving landslides
In some mountainous terrain, debris flows preferentially initiate from the toes and margins of larger, deeper, slower-moving landslides. During the wet winter of 1997, we began real-time monitoring of the large, active Cleveland Corral landslide complex in California, USA. When the main slide is actively moving, small, shallow, first-time slides on the toe and margins mobilize into...
Authors
M.E. Reid, D.L. Brien, R.G. LaHusen, J. J. Roering, J. de la Fuente, S. D. Ellen
Timing of recent accelerations of Pine Island Glacier, Antarctica Timing of recent accelerations of Pine Island Glacier, Antarctica
We have used Interferometric Synthetic Aperture Radar (InSAR) data and sequential Landsat imagery to identify and temporally constrain two acceleration events on Pine Island Glacier (PIG). These two events are separated by a period of at least seven years (1987 - 1994). The change in discharge between two flux gates indicates that the majority of the increase in discharge associated with...
Authors
I. Joughin, Eric Rignot, Christine E. Rosanova, Baerbel K. Lucchitta, J. Bohlander
Volcano seismology Volcano seismology
A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of portable broadband seismic instrumentation, availability...
Authors
B. Chouet
Hilbert-Huang transform analysis of dynamic and earthquake motion recordings Hilbert-Huang transform analysis of dynamic and earthquake motion recordings
This study examines the rationale of Hilbert-Huang transform (HHT) for analyzing dynamic and earthquake motion recordings in studies of seismology and engineering. In particular, this paper first provides the fundamentals of the HHT method, which consist of the empirical mode decomposition (EMD) and the Hilbert spectral analysis. It then uses the HHT to analyze recordings of hypothetical...
Authors
R.R. Zhang, S. Ma, E. Safak, S. Hartzell
Volcanic debris flows in developing countries - The extreme need for public education and awareness of debris-flow hazards Volcanic debris flows in developing countries - The extreme need for public education and awareness of debris-flow hazards
In many developing countries, volcanic debris flows pose a significant societal risk owing to the distribution of dense populations that commonly live on or near a volcano. At many volcanoes, modest volume (up to 500,000 m 3) debris flows are relatively common (multiple times per century) and typically flow at least 5 km along established drainages. Owing to typical debris-flow...
Authors
J. J. Major, S. P. Schilling, C.R. Pullinger
The debris-flow rheology myth The debris-flow rheology myth
Models that employ a fixed rheology cannot yield accurate interpretations or predictions of debris-flow motion, because the evolving behavior of debris flows is too complex to be represented by any rheological equation that uniquely relates stress and strain rate. Field observations and experimental data indicate that debris behavior can vary from nearly rigid to highly fluid as a...
Authors
R.M. Iverson
Exposed water ice discovered near the south pole of Mars Exposed water ice discovered near the south pole of Mars
The Mars Odyssey Thermal Emission Imaging System (THEMIS) has discovered water ice exposed near the edge of Mars' southern perennial polar cap. The surface H2O ice was first observed by THEMIS as a region that was cooler than expected for dry soil at that latitude during the summer season. Diurnal and seasonal temperature trends derived from Mars Global Surveyor Thermal Emission...
Authors
Timothy N. Titus, Hugh H. Kieffer, Phillip R. Christensen
Causes of coral reef degradation Causes of coral reef degradation
No abstract available.
Authors
R.B. Aronson, J.F. Bruno, W.F. Precht, P.W. Glynn, C. D. Harvell, L. Kaufman, C.S. Rogers, E.A. Shinn, J.F. Valentine, J.M. Pandolfi, R.H. Bradbury, E. Sala, T.P. Hughes, K.A. Bjorndal, R.G. Cooke, D. McArdle, L. McClenachan, M.J.H. Newman, G. Paredes, R.R. Warner, J.B.C. Jackson, A.H. Baird, D.R. Bellwood, S.R. Connolly, C. Folke, R. Grosberg, O. Hoegh-Guldberg, J. Kleypas, J.M. Lough, P. Marshall, M. Nystram, S.R. Palumbi, B. Rosen, J. Roughgarden
Documentation for 2003 USGS Seismic Hazard Maps for Puerto Rico and the U.S. Virgin Islands Documentation for 2003 USGS Seismic Hazard Maps for Puerto Rico and the U.S. Virgin Islands
No abstract available.
Authors
C.S. Mueller, A.D. Frankel, M.D. Petersen, E. V. Leyendecker
Emergency Assessment of Debris-Flow Hazards from Basins Burned by the Grand Prix and Old Fires of 2003, Southern California Emergency Assessment of Debris-Flow Hazards from Basins Burned by the Grand Prix and Old Fires of 2003, Southern California
These maps present preliminary assessments of the probability of debris-flow activity and estimates of peak discharges that can potentially be generated by debris flows issuing from basins burned by the Old and Grand Prix Fires of October 2003 in southern California in response to the 25-year, 10-year, and 2-year recurrence, 1-hour duration rain storms. The probability maps are based on...
Authors
Susan H. Cannon, Joseph E. Gartner, Michael G. Rupert, John A. Michael, Dean Djokic, Sreeresh Sreedhar
Estimating debris-flow probability using fan stratigraphy, historic records, and drainage-basin morphology, Interstate 70 highway corridor, central Colorado, U.S.A Estimating debris-flow probability using fan stratigraphy, historic records, and drainage-basin morphology, Interstate 70 highway corridor, central Colorado, U.S.A
We have used stratigraphic and historic records of debris-flows to estimate mean recurrence intervals of past debris-flow events on 19 fans along the Interstate 70 highway corridor in the Front Range of Colorado. Estimated mean recurrence intervals were used in the Poisson probability model to estimate the probability of future debris-flow events on the fans. Mean recurrence intervals...
Authors
J. A. Coe, J. W. Godt, M. Parise, A. Moscariello