Publications
Filter Total Items: 7492
Regional and grain size influences on the geochemistry of soil at Gusev Crater Regional and grain size influences on the geochemistry of soil at Gusev Crater
Congruous with earlier work, Martian soil along the Spirit Rover's traverse at Gusev crater can be divided into three broad groups by size: fines (
Authors
Suniti Karunatillake, Scott M. McLennan, Kenneth E. Herkenhoff
Gone with the wind: Eolian erasure of the Mars Rover tracks Gone with the wind: Eolian erasure of the Mars Rover tracks
The wheel tracks left by the Mars Exploration Rovers Spirit and Opportunity are unique artificial markings on the surface of Mars. The tracks stretch several kilometers across diverse terrain in two widely separated regions of the planet. The initial appearance and characteristics of the tracks were well documented by the science and navigation cameras aboard the vehicles at the time the...
Authors
Paul E. Geissler, R. Sullivan, M. Golombek, J. R. Johnson, Kenneth E. Herkenhoff, N. Bridges, Amy Vaughan, J. Maki, T. Parker, J. Bell
Spirit Mars Rover Mission: Overview and selected results from the northern Home Plate Winter Haven to the side of Scamander crater Spirit Mars Rover Mission: Overview and selected results from the northern Home Plate Winter Haven to the side of Scamander crater
This paper summarizes Spirit Rover operations in the Columbia Hills, Gusev crater, from sol 1410 (start of the third winter campaign) to sol 2169 (when extrication attempts from Troy stopped to winterize the vehicle) and provides an overview of key scientific results. The third winter campaign took advantage of parking on the northern slope of Home Plate to tilt the vehicle to track the...
Authors
R. E. Arvidson, J.F. Bell, P. Bellutta, N.A. Cabrol, J.G. Catalano, J. Cohen, L.S. Crumpler, D. J. Des Marais, T.A. Estlin, W.H. Farrand, R. Gellert, J. A. Grant, Rebecca N Greenberger, E.A. Guinness, Kenneth E. Herkenhoff, J.A. Herman, K.D. Iagnemma, J. R. Johnson, G. Klingelhoefer, K.A. Lichtenberg, S.A. Maxwell, D. W. Ming, R.V. Morris, M.S. Rice, S. W. Ruff, A. Shaw, Kirsten L. Siebach, Paulo A. de Souza, A.W. Stroupe, S. W. Squyres, R.J. Sullivan, K.P. Talley, J.A. Townsend, A. Wang, J.R. Wright, A. S. Yen
Mineralogy and chemistry of cobbles at Meridiani Planum, Mars, investigated by the Mars Exploration Rover Opportunity Mineralogy and chemistry of cobbles at Meridiani Planum, Mars, investigated by the Mars Exploration Rover Opportunity
Numerous loose rocks with dimensions of a few centimeters to tens of centimeters and with no obvious physical relationship to outcrop rocks have been observed along the traverse of the Mars Exploration Rover Opportunity. To date, about a dozen of these rocks have been analyzed with Opportunity's contact instruments, providing information about elemental chemistry (Alpha Particle X‐ray...
Authors
I. Fleischer, J. Bruckner, C. Schroder, W. Farrand, E. Treguier, R.V. Morris, G. Klingelhoefer, Kenneth E. Herkenhoff, David W. Mittlefehldt, J. Ashley, M. Golombek, J. R. Johnson, B. Jolliff, Steve W. Squyres, C. Weitz, R. Gellert, Paulo A. de Souza, B. A. Cohen
Seismicity of the Earth 1900-2010, Aleutian arc and vicinity Seismicity of the Earth 1900-2010, Aleutian arc and vicinity
This map shows details of the Aleutian arc not visible in an earlier publication. The Aleutian arc extends about 3,000 km from the Gulf of Alaska to the Kamchatka Peninsula. It marks the region where the Pacific plate subducts into the mantle beneath the North America plate. This subduction is responsible for the generation of the Aleutian Islands and the deep offshore Aleutian Trench...
Authors
Harley M. Benz, Matthew Herman, Arthur C. Tarr, Gavin P. Hayes, Kevin P. Furlong, Antonio Villaseñor, Richard L. Dart, Susan Rhea
A comparison of Martian north and south polar cold spots and the long‐term effects of the 2001 global dust storm A comparison of Martian north and south polar cold spots and the long‐term effects of the 2001 global dust storm
In the 1970s, Viking and Mariner observed areas in the polar regions of Mars with winter brightness temperatures below the expected kinetic temperatures for CO2 ice sublimation. These areas have since been termed “cold spots” and have been identified as surface deposits of CO2 atmospheric condensates and, occasionally, active CO2 storms. Three Mars years of data from the Mars Global...
Authors
C. Cornwall, Timothy N. Titus
Volcano collapse promoted by progressive strength reduction: New data from Mount St. Helens Volcano collapse promoted by progressive strength reduction: New data from Mount St. Helens
Rock shear strength plays a fundamental role in volcano flank collapse, yet pertinent data from modern collapse surfaces are rare. Using samples collected from the inferred failure surface of the massive 1980 collapse of Mount St. Helens (MSH), we determined rock shear strength via laboratory tests designed to mimic conditions in the pre-collapse edifice. We observed that the 1980...
Authors
Mark E. Reid, Terry E.C. Keith, Robert E. Kayen, Neal R. Iverson, Richard M. Iverson, Dianne Brien
Proceedings of the 25th Himalaya-Karakoram-Tibet Workshop Proceedings of the 25th Himalaya-Karakoram-Tibet Workshop
For a quarter of a century the Himalayan-Karakoram-Tibet (HKT) Workshop has provided scientists studying the India-Asia collision system a wonderful opportunity for workshop-style discussion with colleagues working in this region. In 2010, HKT returns to North America for the first time since 1996. The 25th international workshop is held from June 7 to10 at San Francisco State University
Authors
Mary L. Leech, Simon L. Klemperer, Walter D. Mooney
Channel change and bed-material transport in the Lower Chetco River, Oregon Channel change and bed-material transport in the Lower Chetco River, Oregon
The lower Chetco River is a wandering gravel-bed river flanked by abundant and large gravel bars formed of coarse bed-material sediment. Since the early twentieth century, the large gravel bars have been a source of commercial aggregate for which ongoing permitting and aquatic habitat concerns have motivated this assessment of historical channel change and sediment transport rates...
Authors
J. Rose Wallick, Scott W. Anderson, Charles Cannon, Jim E. O'Connor
Global geological mapping of Ganymede Global geological mapping of Ganymede
We have compiled a global geological map of Ganymede that represents the most recent understanding of the satellite based on Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. We discuss the material...
Authors
G. Wesley Patterson, Geoffrey C. Collins, James W. Head, Robert T. Pappalardo, Louise M. Prockter, Baerbel K. Lucchitta, Jonathan P. Kay
Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587–1996) Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587–1996)
The whole territory of Ecuador is exposed to seismic hazard. Great earthquakes can occur in the subduction zone (e.g. Esmeraldas, 1906, Mw8.8), whereas lower magnitude but shallower and potentially more destructive earthquakes can occur in the highlands. This study focuses on the historical crustal earthquakes of the Andean Cordillera. Several large cities are located in the Interandean...
Authors
Celine Beauval, Hugo Yepes, William H. Bakun, Jose Egred, Alexandra Alvarado, Juan-Carlos Singaucho
Periodic, chaotic, and doubled earthquake recurrence intervals on the deep San Andreas Fault Periodic, chaotic, and doubled earthquake recurrence intervals on the deep San Andreas Fault
Earthquake recurrence histories may provide clues to the timing of future events, but long intervals between large events obscure full recurrence variability. In contrast, small earthquakes occur frequently, and recurrence intervals are quantifiable on a much shorter time scale. In this work, I examine an 8.5-year sequence of more than 900 recurring low-frequency earthquake bursts...
Authors
David R. Shelly