Publications
Products (journal articles, reports, fact sheets) authored by current and past scientists are listed below. Please check the USGS Pubs Warehouse for other USGS publications.
Filter Total Items: 2018
Rocky VI -- Climate - A hot time in the old town tonight Rocky VI -- Climate - A hot time in the old town tonight
No abstract available.
Authors
W. H. Langer
Rocky VII -- All that glitters is not gold Rocky VII -- All that glitters is not gold
No abstract available.
Authors
W. H. Langer
Devonian brachiopods of southwesternmost laurentia: Biogeographic affinities and tectonic significance Devonian brachiopods of southwesternmost laurentia: Biogeographic affinities and tectonic significance
Three brachiopod faunas discussed herein record different depositional and tectonic settings along the southwestern margin of Laurentia (North America) during Devonian time. Depositional settings include inner continental shelf (Cerros de Los Murcielagos), medial continental shelf (Rancho Placeritos), and offshelf continental rise (Rancho Los Chinos). Ages of Devonian brachiopod faunas...
Authors
A. J. Boucot, Forrest G. Poole, R. Amaya-Martinez, A. G. Harris, Charles Sandberg, William R. Page
Evolution of Devonian carbonate-shelf margin, Nevada Evolution of Devonian carbonate-shelf margin, Nevada
The north-trending, 550-km-long Nevada segment of the Devonian carbonate-shelf margin, which fringed western North America, evidences the complex interaction of paleotectonics, eustasy, biotic changes, and bolide impact-related influences. Margin reconstruction is complicated by mid-Paleozoic to Paleogene compressional tectonics and younger extensional and strike-slip faulting. Reports...
Authors
J. R. Morrow, Charles Sandberg
Orbital identification of carbonate-bearing rocks on Mars Orbital identification of carbonate-bearing rocks on Mars
Geochemical models for Mars predict carbonate formation during aqueous alteration. Carbonate-bearing rocks had not previously been detected on Mars' surface, but Mars Reconnaissance Orbiter mapping reveals a regional rock layer with near-infrared spectral characteristics that are consistent with the presence of magnesium carbonate in the Nili Fossae region. The carbonate is closely...
Authors
B.L. Ehlmann, J.F. Mustard, S.L. Murchie, F. Poulet, J.L. Bishop, A.J. Brown, W. M. Calvin, R. N. Clark, D.J. Des Marais, R.E. Milliken, L.H. Roach, T. L. Roush, G.A. Swayze, J.J. Wray
The Early Oligocene Copperas Creek Volcano and geology along New Mexico Higway 15 between Sapillo Creek and the Gila Cliff Dwellings National Monument, Grant and Catron Counties, New Mexico The Early Oligocene Copperas Creek Volcano and geology along New Mexico Higway 15 between Sapillo Creek and the Gila Cliff Dwellings National Monument, Grant and Catron Counties, New Mexico
The section of New Mexico Highway 15 between the intersection of NM-15 and NM 35 (aka Sapillo junction) at the south and the Gila Cliff Dwellings National Monument at the north end of NM –15 occupies an approximately 18 mile long, mile wide, corridor through the eastern part of the Gila Wilderness (Fig. 1). Whereas most of the Gila Wilderness is dominated by silicic, caldera-forming...
Authors
James C. Ratte
Bjørn Bølviken - 2008 IAGC Vernadsky medalist Bjørn Bølviken - 2008 IAGC Vernadsky medalist
Prof. Bjørn Bølviken, 80, formerly with the Geological Survey of Norway, was the 2nd recipient of the IAGC's Vernadsky Medal. The IAGC Vernadsky Medal is awarded biennially to a single person for a distinguished record of scientific accomplishment in geochemistry over the course of a career. Dr. David Smith of the US Geological Survey and Leader of the IAGC Working Group on ‘Global...
Authors
David B. Smith
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
Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument
Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L’Eau, les Glaces et l’Activitié) instrument1,2, preserve a record of the interaction of water with rocks on Mars. Global mapping showed that phyllosilicates are widespread but are apparently restricted to ancient terrains and a relatively narrow range of...
Authors
J.F. Mustard, S.L. Murchie, S.M. Pelkey, B.L. Ehlmann, R.E. Milliken, J. A. Grant, J.-P. Bibring, F. Poulet, J. Bishop, E. N. Dobrea, L. Roach, F. Seelos, R. E. Arvidson, S. Wiseman, R. Green, C. Hash, D. Humm, E. Malaret, J.A. McGovern, K. Seelos, T. Clancy, R. Clark, D. des Marais, N. Izenberg, A. Knudson, Y. Langevin, T. Martin, P. McGuire, Robert Morris, M. Robinson, T. Roush, M. Smith, G. Swayze, H. Taylor, T. Titus, M. Wolff
Mapping and interpretation of Sinlap crater on Titan using Cassini VIMS and RADAR data Mapping and interpretation of Sinlap crater on Titan using Cassini VIMS and RADAR data
Only a few impact craters have been unambiguously detected on Titan by the Cassini-Huygens mission. Among these, Sinlap is the only one that has been observed both by the RADAR and VIMS instruments. This paper describes observations at centimeter and infrared wavelengths which provide complementary information about the composition, topography, and surface roughness. Several units appear...
Authors
Stéphane Le Mouélic, P. Paillou, M.A. Janssen, J. W. Barnes, S. Rodriguez, Christophe Sotin, R. Brown, K. H. Baines, B. J. Buratti, R. N. Clark, M. Crapeau, P.J. Encrenaz, R. Jaumann, D. Geudtner, F. Paganelli, L. Soderblom, G. Tobie, S. Wall
Identification of spectral units on Phoebe Identification of spectral units on Phoebe
We apply a multivariate statistical method to the Phoebe spectra collected by the VIMS experiment onboard the Cassini spacecraft during the flyby of June 2004. The G-mode clustering method, which permits identification of the most important features in a spectrum, is used on a small subset of data, characterized by medium and high spatial resolution, to perform a raw spectral...
Authors
A. Coradini, F. Tosi, A.I. Gavrishin, F. Capaccioni, P. Cerroni, G. Filacchione, A. Adriani, R. Brown, G. Bellucci, V. Formisano, E. D’Aversa, J. I. Lunine, K. H. Baines, J.-P. Bibring, B. J. Buratti, R. N. Clark, D. P. Cruikshank, M. Combes, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, R.M. Nelson, P. Nicholson, B. Sicardy, Christophe Sotin, M.M. Hedman, G. B. Hansen, C. A. Hibbitts, M. Showalter, C. Griffith, G. Strazzulla
Hydrocarbons on Saturn's satellites Iapetus and Phoebe Hydrocarbons on Saturn's satellites Iapetus and Phoebe
Material of low geometric albedo (pV ??? 0.1) is found on many objects in the outer Solar System, but its distribution in the saturnian satellite system is of special interest because of its juxtaposition with high-albedo ice. In the absence of clear, diagnostic spectral features, the composition of this low-albedo (or "dark") material is generally inferred to be carbon-rich, but the...
Authors
D. P. Cruikshank, E. Wegryn, Ore Dalle, R. Brown, J.-P. Bibring, B. J. Buratti, R. N. Clark, T. B. McCord, P. Nicholson, Y.J. Pendleton, T.C. Owen, G. Filacchione, A. Coradini, P. Cerroni, F. Capaccioni, R. Jaumann, R.M. Nelson, K. H. Baines, Christophe Sotin, G. Bellucci, M. Combes, Y. Langevin, B. Sicardy, D. L. Matson, V. Formisano, P. Drossart, V. Mennella