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Seasonal activity and morphological changes in martian gullies Seasonal activity and morphological changes in martian gullies

Recent studies of martian dune and non-dune gullies have suggested a seasonal control on present-day gully activity. The timing of current gully activity, especially activity involving the formation or modification of channels (which commonly have been taken as evidence of fluvial processes), has important implications regarding likely gully formation processes and necessary...
Authors
Colin M. Dundas, Serina Diniega, Candice J. Hansen, Shane Byrne, Alfred S. McEwen

Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results

American Samoa and the neighboring islands of the South Pacific lie near active tectonic-plate boundaries that host many large earthquakes which can result in strong earthquake shaking and tsunamis. To mitigate earthquake risks from future ground shaking, the Federal Emergency Management Agency requested that the U.S. Geological Survey prepare seismic hazard maps that can be applied in...
Authors
Mark D. Petersen, Stephen C. Harmsen, Kenneth S. Rukstales, Charles S. Mueller, Daniel E. McNamara, Nicolas Luco, Melanie Walling

Surface properties of the Mars Science Laboratory candidate landing sites: characterization from orbit and predictions Surface properties of the Mars Science Laboratory candidate landing sites: characterization from orbit and predictions

This work describes the interpretation of THEMIS-derived thermal inertia data at the Eberswalde, Gale, Holden, and Mawrth Vallis Mars Science Laboratory (MSL) candidate landing sites and determines how thermophysical variations correspond to morphology and, when apparent, mineralogical diversity. At Eberswalde, the proportion of likely unconsolidated material relative to exposed bedrock...
Authors
R.L. Fergason, P. R. Christensen, M.P. Golombek, T. J. Parker

Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars

A multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness (1.5–2 km at some locations) of the...
Authors
M. Ramy El Maarry, James M. Dohm, Giuseppe A. Marzo, Robin Fergason, Walter Goetz, Essam Heggy, Andreas Pack, Wojciech J. Markiewicz

Dissolved and colloidal trace elements in the Mississippi River Delta outflow after Hurricanes Katrina and Rita Dissolved and colloidal trace elements in the Mississippi River Delta outflow after Hurricanes Katrina and Rita

The Mississippi River delta outflow region is periodically disturbed by tropical weather systems including major hurricanes, which can terminate seasonal bottom water hypoxia and cause the resuspension of shelf bottom sediments which could result in the injection of trace elements into the water column. In the summer of 2005, Hurricanes Katrina and Rita passed over the Louisiana Shelf...
Authors
Moo-Joon Shim, Peter W. Swarzenski, Alan M. Shiller

Deterministic estimation of hydrological thresholds for shallow landslide initiation and slope stability models: case study from the Somma-Vesuvius area of southern Italy Deterministic estimation of hydrological thresholds for shallow landslide initiation and slope stability models: case study from the Somma-Vesuvius area of southern Italy

Rainfall-induced debris flows involving ash-fall pyroclastic deposits that cover steep mountain slopes surrounding the Somma-Vesuvius volcano are natural events and a source of risk for urban settlements located at footslopes in the area. This paper describes experimental methods and modelling results of shallow landslides that occurred on 5–6 May 1998 in selected areas of the Sarno...
Authors
Rex L. Baum, Jonathan W. Godt, P. De Vita, E. Napolitano

Geometric derivations of minimal sets of sufficient multiview constraints Geometric derivations of minimal sets of sufficient multiview constraints

Geometric interpretations of four of the most common determinant formulations of multiview constraints are given, showing that they all enforce the same geometry and that all of the forms commonly in use in the machine vision community are a subset of a more general form. Generalising the work of Yi Ma yields a new general 2 x 2 determinant trilinear and 3 x 3 determinant quadlinear...
Authors
Orrin H. Thomas, Edward R. Oshel

Assessment of environments for Mars Science Laboratory entry, descent, and surface operations Assessment of environments for Mars Science Laboratory entry, descent, and surface operations

The Mars Science Laboratory mission aims to land a car-sized rover on Mars' surface and operate it for at least one Mars year in order to assess whether its field area was ever capable of supporting microbial life. Here we describe the approach used to identify, characterize, and assess environmental risks to the landing and rover surface operations. Novel entry, descent, and landing...
Authors
Ashwin R. Vasavada, Allen Chen, Jeffrey R. Barnes, P. Daniel Burkhart, Bruce A. Cantor, Alicia M. Dwyer-Cianciolo, Robini L. Fergason, David P. Hinson, Hilary L. Justh, David M. Kass, Stephen R. Lewis, Michael A. Mischna, James R. Murphy, Scot C.R. Rafkin, Daniel Tyler, Paul G. Withers
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