Publications
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THEMIS VIS and IR observations of a high-altitude Martian dust devil THEMIS VIS and IR observations of a high-altitude Martian dust devil
The Mars Odyssey Thermal Emission Imaging System (THEMIS) imaged a Martian dust devil in both visible and thermal-infrared wavelengths on January 30, 2004. We believe this is the first documented infrared observation of an extraterrestrial dust devil, and the highest to be directly observed at more than 16 kilometers above the equatorial geoid of Mars. This dust devil measured over 700...
Authors
Glen Cushing, Timothy N. Titus, Phillip R. Christensen
The ubiquitous nature of accessory calcite in granitoid rocks: Implications for weathering, solute evolution, and petrogenesis The ubiquitous nature of accessory calcite in granitoid rocks: Implications for weathering, solute evolution, and petrogenesis
Calcite is frequently cited as a source of excess Ca, Sr and alkalinity in solutes discharging from silicate terrains yet, no previous effort has been made to assess systematically the overall abundance, composition and petrogenesis of accessory calcite in granitoid rocks. This study addresses this issue by analyzing a worldwide distribution of more than 100 granitoid rocks. Calcite is...
Authors
A. F. White, M. S. Schulz, J. B. Lowenstern, D.V. Vivit, T.D. Bullen
Provenance and diagenesis of the evaporite-bearing Burns formation, Meridiani Planum, Mars Provenance and diagenesis of the evaporite-bearing Burns formation, Meridiani Planum, Mars
Impure reworked evaporitic sandstones, preserved on Meridiani Planum, Mars, are mixtures of roughly equal amounts of altered siliciclastic debris, of basaltic provenance (40 ± 10% by mass), and chemical constituents, dominated by evaporitic minerals (jarosite, Mg-, Ca-sulfates ± chlorides ± Fe-, Na-sulfates), hematite and possibly secondary silica (60 ± 10%). These chemical constituents...
Authors
S. M. McLennan, J.F. Bell, W. M. Calvin, P. R. Christensen, B.C. Clark, P.A. de Souza, J. Farmer, W. H. Farrand, D.A. Fike, Ralf Gellert, A. Ghosh, T.D. Glotch, J.P. Grotzinger, B. Hahn, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, S.S. Johnson, B. Jolliff, G. Klingelhofer, A.H. Knoll, Z. Learner, M. C. Malin, H.Y. McSween, J. Pocock, S. W. Ruff, Laurence A. Soderblom, S. W. Squyres, N.J. Tosca, W.A. Watters, M.B. Wyatt, A. Yen
Global Positioning System measurements on the island of Hawai`i: 1997 through 2004 Global Positioning System measurements on the island of Hawai`i: 1997 through 2004
This report summarizes GPS data and observations collected between 1997 and 2004 on the island of Hawai‘i with static surveying and continuously recording instruments. On Kīlauea, the long-term deformation field is dominated by steady southeastern velocities of more than 6 cm/year and uplift of about 2 cm/yr at stations on the south flank (with respect to a fixed Pacific Plate)...
Authors
Asta Miklius, Peter Cervelli, Maurice Sako, Michael Lisowski, Susan Owen, Paul Segal, James Foster, Kevan Kamibayashi, Ben Brooks
Landslide hazards: A national threat Landslide hazards: A national threat
Landslides occur and can cause damage in all 50 States. Severe storms, earthquakes, volcanic activity, coastal wave attack, and wildfires can cause widespread slope instability. Landslide danger may be high even as emergency personnel are providing rescue and recovery services. To address landslide hazards, several questions must be considered: Where and when will landslides occur? How...
Authors
Water Resources Division U.S. Geological Survey
Surface deformation associated with the March 1996 earthquake swarm at Akutan Island, Alaska, revealed by C-band ERS and L-band JERS radar interferometry Surface deformation associated with the March 1996 earthquake swarm at Akutan Island, Alaska, revealed by C-band ERS and L-band JERS radar interferometry
In March 1996, an intense earthquake swarm beneath Akutan Island, Alaska, was accompanied by extensive ground cracking but no eruption of Akutan volcano. Radar interferograms produced from L-band JERS-1 and C-band ERS-1/2 images show uplift associated with the swarm by as much as 60 cm on the western part of the island. The JERS-1 interferogram has greater coherence, especially in areas...
Authors
Z. Lu, C. Wicks, O. Kwoun, J.A. Power, D. Dzurisin
Estimation of regional material yield from coastal landslides based on historical digital terrain modelling Estimation of regional material yield from coastal landslides based on historical digital terrain modelling
High-resolution historical (1942) and recent (1994) digital terrain models were derived from aerial photographs along the Big Sur coastline in central California to measure the long-term volume of material that enters the nearshore environment. During the 52-year measurement time period, an average of 21 000 ?? 3100 m3 km-1 a-1 of material was eroded from nine study sections distributed...
Authors
C.J. Hapke
An alternative approach to characterize nonlinear site effects An alternative approach to characterize nonlinear site effects
This paper examines the rationale of a method of nonstationary processing and analysis, referred to as the Hilbert-Huang transform (HHT), for its application to a recording-based approach in quantifying influences of soil nonlinearity in site response. In particular, this paper first summarizes symptoms of soil nonlinearity shown in earthquake recordings, reviews the Fourier-based...
Authors
R.R. Zhang, S. Hartzell, J. Liang, Y. Hu
Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation
Okmok volcano, located in the central Aleutian arc, Alaska, is a dominantly basaltic complex topped with a 10-km-wide caldera that formed circa 2.05 ka. Okmok erupted several times during the 20th century, most recently in 1997; eruptions in 1945, 1958, and 1997 produced lava flows within the caldera. We used 80 interferometric synthetic aperture radar (InSAR) images (interferograms) to...
Authors
Z. Lu, Timothy Masterlark, Daniel Dzurisin
Undersea landslides: Extent and significance in the Pacific Ocean, an update Undersea landslides: Extent and significance in the Pacific Ocean, an update
Submarine landslides are known to occur disproportionately in a limited number of environments including fjords, deltas, canyons, volcanic islands and the open continental slope. An evaluation of the progress that has been made in understanding Pacific Ocean submarine landslides over the last 15 years shows that mapping technologies have improved greatly, allowing a better interpretation...
Authors
H.J. Lee
Monitoring eruptive activity at Mount St. Helens with TIR image data Monitoring eruptive activity at Mount St. Helens with TIR image data
Thermal infrared (TIR) data from the MASTER airborne imaging spectrometer were acquired over Mount St. Helens in Sept and Oct, 2004, before and after the onset of recent eruptive activity. Pre‐eruption data showed no measurable increase in surface temperatures before the first phreatic eruption on Oct 1. MASTER data acquired during the initial eruptive episode on Oct 14 showed maximum...
Authors
R.G. Vaughan, S.J. Hook, M.S. Ramsey, V.J. Realmuto, D.J. Schneider
Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting
Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume...
Authors
Gregory P. Waite, D.L. Schutt, Robert B. Smith