Publications
Filter Total Items: 336
Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars
Observations by the Mars Reconnaissance Orbiter/Compact Reconnaissance Imaging Spectrometer for Mars in the Mawrth Vallis region show several phyllosilicate species, indicating a wide range of past aqueous activity. Iron/magnesium (Fe/Mg)-smectite is observed in light-toned outcrops that probably formed via aqueous alteration of basalt of the ancient cratered terrain. This unit is...
Authors
J.L. Bishop, E.Z.N. Dobrea, N.K. McKeown, M. Parente, B.L. Ehlmann, J.R. Michalski, R.E. Milliken, F. Poulet, G.A. Swayze, J.F. Mustard, S.L. Murchie, J.-P. Bibring
Integrated geoscience studies in the Greater Yellowstone Area - Volcanic, tectonic, and hydrothermal processes in the Yellowstone geoecosystem Integrated geoscience studies in the Greater Yellowstone Area - Volcanic, tectonic, and hydrothermal processes in the Yellowstone geoecosystem
Yellowstone National Park, rimmed by a crescent of older mountainous terrain, has at its core the Quaternary Yellowstone Plateau, an undulating landscape shaped by forces of volcanism, tectonism, and later glaciation. Its spectacular hydrothermal systems cap this landscape. From 1997 through 2003, the United States Geological Survey Mineral Resources Program conducted a multidisciplinary...
Preliminary analytical results for ash and burned soils from the October 2007 southern California wildfires Preliminary analytical results for ash and burned soils from the October 2007 southern California wildfires
The U.S. Geological Survey (USGS) collected ash and burned soils from about 28 sites in southern California wildfire areas (Harris, Witch, Ammo, Santiago, Canyon and Grass Valley) from Nov. 2 through 9, 2007 (table 1). USGS researchers are applying a wide variety of analytical methods to these samples, with the goal of helping identify characteristics of the ash and soils from wildland...
Authors
Geoffrey S. Plumlee, Deborah A. Martin, Todd Hoefen, Raymond F. Kokaly, Philip Hageman, Alison Eckberg, Gregory P. Meeker, Monique Adams, Michael Anthony, Paul J. Lamothe
Questa baseline and pre-mining ground-water quality investigation. 19. Leaching characteristics of composited materials from mine waste-rock piles and naturally altered areas near Questa, New Mexico Questa baseline and pre-mining ground-water quality investigation. 19. Leaching characteristics of composited materials from mine waste-rock piles and naturally altered areas near Questa, New Mexico
The goal of this study is to compare and contrast the leachability of metals and the acidity from individual mine waste-rock piles and natural erosional scars in the study area near Questa, New Mexico. Surficial multi-increment (composite) samples less than 2 millimeters in diameter from five waste-rock piles, nine erosional-scar areas, a less-altered site, and a tailings slurry-pipe...
Authors
Kathleen S. Smith, Philip L. Hageman, Paul H. Briggs, Stephen J. Sutley, R. Blaine McCleskey, K. Eric Livo, Philip L. Verplanck, Monique G. Adams, Pamela A. Gemery-Hill
USGS Digital Spectral Library splib06a USGS Digital Spectral Library splib06a
Introduction We have assembled a digital reflectance spectral library that covers the wavelength range from the ultraviolet to far infrared along with sample documentation. The library includes samples of minerals, rocks, soils, physically constructed as well as mathematically computed mixtures, plants, vegetation communities, microorganisms, and man-made materials. The samples and...
Authors
Roger N. Clark, Gregg A. Swayze, Richard A. Wise, K. Eric Livo, Todd M. Hoefen, Raymond F. Kokaly, Stephen J. Sutley
Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah
Results of chemical and some isotopic analyses of soil, shale, and water extracts collected from the surface, trenches, and pits in the Mancos Shale are presented in this report. Most data are for sites on the Gunnison Gorge National Conservation Area (GGNCA) in southwestern Colorado. For comparison, data from a few sites from the Mancos landscape near Hanksville, Utah, are included...
Authors
Michele L.W. Tuttle, Juli Fahy, Richard I. Grauch, Bridget A. Ball, Geneva W. Chong, John G. Elliott, John J. Kosovich, Keith E. Livo, Lisa L. Stillings
Characterization of post-fire surface cover, soils, and burn severity at the Cerro Grande Fire, New Mexico, using hyperspectral and multispectral remote sensing Characterization of post-fire surface cover, soils, and burn severity at the Cerro Grande Fire, New Mexico, using hyperspectral and multispectral remote sensing
Forest fires leave behind a changed ecosystem with a patchwork of surface cover that includes ash, charred organic matter, soils and soil minerals, and dead, damaged, and living vegetation. The distributions of these materials affect post-fire processes of erosion, nutrient cycling, and vegetation regrowth. We analyzed high spatial resolution (2.4??m pixel size) Airborne Visible and...
Authors
R.F. Kokaly, B.W. Rockwell, S.L. Haire, T. V. V. King
Saturn's dynamic D ring Saturn's dynamic D ring
The Cassini spacecraft has provided the first clear images of the D ring since the Voyager missions. These observations show that the structure of the D ring has undergone significant changes over the last 25 years. The brightest of the three ringlets seen in the Voyager images (named D72), has transformed from a narrow,
Authors
M.M. Hedman, J.A. Burns, M.R. Showalter, C.C. Porco, P. D. Nicholson, A.S. Bosh, M.S. Tiscareno, R. H. Brown, B. J. Buratti, K. H. Baines, R. Clark
Saturn's icy satellites investigated by Cassini-VIMS. I. Full-disk properties: 350-5100 nm reflectance spectra and phase curves Saturn's icy satellites investigated by Cassini-VIMS. I. Full-disk properties: 350-5100 nm reflectance spectra and phase curves
Saturn's icy satellites are among the main scientific objectives of the Cassini-VIMS (Visual and Infrared Mapping Spectrometer) experiment. This paper contains a first systematic and comparative analysis of the full-disk spectral properties of Dione, Enceladus, Epimetheus, Hyperion, Iapetus, Mimas, Phoebe, Rhea and Tethys as observed by VIMS from July 2004 to June 2005. The disk...
Authors
G. Filacchione, F. Capaccioni, T. B. McCord, A. Coradini, P. Cerroni, G. Bellucci, F. Tosi, E. D’Aversa, V. Formisano, R. H. Brown, K. H. Baines, J.-P. Bibring, B. J. Buratti, R. N. Clark, M. Combes, D. P. Cruikshank, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, V. Mennella, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin, G. Hansen, K. Hibbitts, M. Showalter, S. Newman
Near-infrared spectral mapping of Titan's mountains and channels Near-infrared spectral mapping of Titan's mountains and channels
We investigate the spectral reflectance properties of channels and mountain ranges on Titan using data from Cassini's Visual and Infrared Mapping Spectrometer (VIMS) obtained during the T9 encounter (26 December 2005). We identify the location of channels and mountains using synthetic aperture radar maps obtained from Cassini's RADAR instrument during the T13 (30 April 2006) flyby...
Authors
Jason W. Barnes, Jani Radebaugh, Robert H. Brown, Steve Wall, Laurence A. Soderblom, Jonathan I. Lunine, Devon M. Burr, Christophe Sotin, Stephane Le Mouelic, Sebastien Rodriguez, Bonnie J. Buratti, Roger N. Clark, Kevin H. Baines, Ralf Jaumann, Philip D. Nicholson, Randolph L. Kirk, Rosaly Lopes, Ralph D. Lorenz, Ken Mitchell, Charles A. Wood
Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site
Titan's vast equatorial fields of RADAR-dark longitudinal dunes seen in Cassini RADAR synthetic aperture images correlate with one of two dark surface units discriminated as “brown” and “blue” in Visible and Infrared Mapping Spectrometer (VIMS) color composites of short-wavelength infrared spectral cubes (RGB as 2.0, 1.6, 1.3 μm). In such composites bluer materials exhibit higher...
Authors
Laurence A. Soderblom, Randolph L. Kirk, Jonathan I. Lunine, Jeffrey A. Anderson, Kevin H. Baines, Jason W. Barnes, Janet M. Barrett, Robert H. Brown, Bonnie J. Buratti, Roger N. Clark, Dale P. Cruikshank, Charles Elachi, Michael A. Janssen, Ralf Jaumann, Erich Karkoschka, Stéphane Le Mouélic, Rosaly Lopes, Ralph D. Lorenz, Thomas B. McCord, Philip D. Nicholson, Jani Radebaugh, Bashar Rizk, Christophe Sotin, Ellen R. Stofan, Tracie L. Sucharski, Martin G. Tomasko, Stephen D. Wall
Global-scale surface spectral variations on Titan seen from Cassini/VIMS Global-scale surface spectral variations on Titan seen from Cassini/VIMS
We present global-scale maps of Titan from the Visual and Infrared Mapping Spectrometer (VIMS) instrument on Cassini. We map at 64 near-infrared wavelengths simultaneously, covering the atmospheric windows at 0.94, 1.08, 1.28, 1.6, 2.0, 2.8, and 5 ??m with a typical resolution of 50 km/pixel or a typical total integration time of 1 s. Our maps have five to ten times the resolution of...
Authors
J. W. Barnes, R. H. Brown, L. Soderblom, B. J. Buratti, Christophe Sotin, S. Rodriguez, S. Le Mouelic, K. H. Baines, R. Clark, P. Nicholson