Publications
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Evidence of phyllosilicates in Wooly Patch, an altered rock encountered at West Spur, Columbia Hills, by the Spirit rover in Gusev crater, Mars Evidence of phyllosilicates in Wooly Patch, an altered rock encountered at West Spur, Columbia Hills, by the Spirit rover in Gusev crater, Mars
On its traverse to Columbia Hills, the Mars Exploration Rover Spirit investigated an outcrop designated “Wooly Patch” that exhibited morphological, mineralogical, and geochemical characteristics at the extreme ends of ranges observed among rocks studied at West Spur, a westward projecting salient near the foot of the Columbia Hills, Gusev crater. The major‐element composition and Fe...
Authors
A. Wang, R.L. Korotev, B.L. Jolliff, L.A. Haskin, L. Crumpler, W. H. Farrand, Kenneth E. Herkenhoff, Jr. de Souza, A.G. Kusack, J.A. Hurowitz, N.J. Tosca
Explosion source strong ground motions in the Mississippi embayment Explosion source strong ground motions in the Mississippi embayment
Two strong-motion arrays were deployed for the October 2002 Embayment Seismic Excitation Experiment to study the spatial variation of strong ground motions in the deep, unconsolidated sediments of the Mississippi embayment because there are no comparable strong-motion data from natural earthquakes in the area. Each linear array consisted of eight three-component K2 accelerographs spaced...
Authors
C.A. Langston, P. Bodin, C. Powell, M. Withers, S. Horton, Walter D. Mooney
Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts
Major-element and volatile (H2O, CO2, S) compositions of glasses from the submarine flanks of Kilauea Volcano record its growth from pre-shield into tholeiite shield-stage. Pillow lavas of mildly alkalic basalt at 2600–1900 mbsl on the upper slope of the south flank are an intermediate link between deeper alkalic volcaniclastics and the modern tholeiite shield. Lava clast glasses from...
Authors
Michelle L. Coombs, Thomas W. Sisson, Peter W. Lipman
Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska: Optimization using InSAR, FEMs, and an adaptive mesh algorithm Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska: Optimization using InSAR, FEMs, and an adaptive mesh algorithm
Interferometric synthetic aperture radar (InSAR) imagery documents the consistent subsidence, during the interval 1992–1999, of a pyroclastic flow deposit (PFD) emplaced during the 1986 eruption of Augustine Volcano, Alaska. We construct finite element models (FEMs) that simulate thermoelastic contraction of the PFD to account for the observed subsidence. Three-dimensional problem...
Authors
Timothy Masterlark, Zhong Lu, Russell P. Rykhus
Simulation of active tectonic processes for a convecting mantle with moving continents Simulation of active tectonic processes for a convecting mantle with moving continents
Numerical models are presented that simulate several active tectonic processes. These models include a continent that is thermally and mechanically coupled with viscous mantle flow. The assumption of rigid continents allows use of solid body equations to describe the continents' motion and to calculate their velocities. The starting point is a quasi-steady state model of mantle...
Authors
V. Trubitsyn, M. Kaban, Walter D. Mooney, C. Reigber, P. Schwintzer
Crustal structure across the Altyn Tagh Range at the northern margin of the Tibetan Plateau and tectonic implications Crustal structure across the Altyn Tagh Range at the northern margin of the Tibetan Plateau and tectonic implications
We present new seismic refraction/wide-angle-reflection data across the Altyn Tagh Range and its adjacent basins. We find that the crustal velocity structure, and by inference, the composition of the crust changes abruptly beneath the Cherchen fault, i.e., ∼100 km north of the northern margin of the Tibetan plateau. North of the Cherchen fault, beneath the Tarim basin, a platform-type...
Authors
J. Zhao, Walter D. Mooney, X. Zhang, Z. Li, Z. Jin, N. Okaya
Characterization and petrologic interpretation of olivine-rich basalts at Gusev Crater, Mars Characterization and petrologic interpretation of olivine-rich basalts at Gusev Crater, Mars
Rocks on the floor of Gusev crater are basalts of uniform composition and mineralogy. Olivine, the only mineral to have been identified or inferred from data by all instruments on the Spirit rover, is especially abundant in these rocks. These picritic basalts are similar in many respects to certain Martian meteorites (olivine-phyric shergottites). The olivine megacrysts in both have...
Authors
H.Y. McSween, M.B. Wyatt, Ralf Gellert, J.F. Bell, R.V. Morris, Kenneth E. Herkenhoff, L.S. Crumpler, K.A. Milam, K.R. Stockstill, L.L. Tornabene, R. E. Arvidson, P. Bartlett, D. Blaney, N.A. Cabrol, P. R. Christensen, B. C. Clark, J.A. Crisp, D.J. Des Marais, T. Economou, J.D. Farmer, W. Farrand, A. Ghosh, M. Golombek, S. Gorevan, R. Greeley, V.E. Hamilton, J. R. Johnson, B.L. Joliff, G. Klingelhofer, A.T. Knudson, S. McLennan, D. Ming, J.E. Moersch, R. Rieder, S. W. Ruff, C. Schroder, P.A. de Souza, S. W. Squyres, H. Wanke, A. Wang, A. Yen, J. Zipfel
Two models for evaluating landslide hazards Two models for evaluating landslide hazards
Two alternative procedures for estimating landslide hazards were evaluated using data on topographic digital elevation models (DEMs) and bedrock lithologies in an area adjacent to the Missouri River in Atchison County, Kansas, USA. The two procedures are based on the likelihood ratio model but utilize different assumptions. The empirical likelihood ratio model is based on non-parametric...
Authors
J.C. Davis, C.-J. Chung, G.C. Ohlmacher
Submarine geology of Hana Ridge and Haleakala Volcano's northeast flank, Maui Submarine geology of Hana Ridge and Haleakala Volcano's northeast flank, Maui
We present a morphostructural analysis of the submarine portions of Haleakala Volcano and environs, based upon a 4-year program of geophysical surveys and submersible explorations of the underwater flanks of Hawaiian volcanoes that was conducted by numerous academic and governmental research organizations in Japan and the U.S. and funded primarily by the Japan Agency for Marine–Earth...
Authors
Barry W. Eakins, Joel E. Robinson
Age model for a continuous, ca 250-ka Quaternary lacustrine record from Bear Lake, Utah-Idaho Age model for a continuous, ca 250-ka Quaternary lacustrine record from Bear Lake, Utah-Idaho
The Quaternary sediments sampled by continuous 120-m-long drill cores from Bear Lake (Utah-Idaho) comprise one of the longest lacustrine sequences recovered from an extant lake. The cores serve as a good case study for the construction of an age model for sequences that extend beyond the range of radiocarbon dating. From a variety of potential age indicators, we selected a combination of
Authors
Steven M. Colman, D. S. Kaufman, Jordon Bright, C. Heil, J.W. King, W.E. Dean, J. G. Rosenbaum, R. M. Forester, J. L. Bischoff, Marie Perkins, J. P. McGeehin
Spectrophotometric properties of materials observed by Pancam on the Mars Exploration Rovers: 2. Opportunity Spectrophotometric properties of materials observed by Pancam on the Mars Exploration Rovers: 2. Opportunity
The Panoramic Camera (Pancam) on the Mars Exploration Rover Opportunity acquired visible/near‐infrared multispectral observations of soils and rocks under varying viewing and illumination geometries that were modeled using radiative transfer theory to improve interpretations of the microphysical and surface scattering nature of materials in Meridiani Planum. Nearly 25,000 individual...
Authors
J. R. Johnson, W.M. Grundy, M.T. Lemmon, J.F. Bell, M. J. Johnson, R. Deen, R. E. Arvidson, W. H. Farrand, E. Guinness, A. G. Hayes, Kenneth E. Herkenhoff, F. Seelos, J. Soderblom, S. Squyres
Shocked plagioclase signatures in Thermal Emission Spectrometer data of Mars Shocked plagioclase signatures in Thermal Emission Spectrometer data of Mars
The extensive impact cratering record on Mars combined with evidence from SNC meteorites suggests that a significant fraction of the surface is composed of materials subjected to variable shock pressures. Pressure-induced structural changes in minerals during high-pressure shock events alter their thermal infrared spectral emission features, particularly for feldspars, in a predictable...
Authors
Jeffrey R. Johnson, Matthew I. Staid, Timothy N. Titus, Kris J. Becker