Publications
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Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan
Cassini's third and fourth radar flybys, T7 and T8, covered diverse terrains in the high southern and equatorial latitudes, respectively. The T7 synthetic aperture radar (SAR) swath is somewhat more straightforward to understand in terms of a progressive poleward descent from a high, dissected, and partly hilly terrain down to a low flat plain with embayments and deposits suggestive of...
Authors
J. I. Lunine, C. Elachi, S. D. Wall, M.A. Janssen, M.D. Allison, Y. Anderson, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Franceschetti, Y. Gim, G. Hamilton, S. Hensley, W.T.K. Johnson, K. Kelleher, Randolph L. Kirk, R.M. Lopes, R. Lorenz, D.O. Muhleman, R. Orosei, S.J. Ostro, F. Paganelli, P. Paillou, G. Picardi, F. Posa, J. Radebaugh, L.E. Roth, R. Seu, S. Shaffer, Laurence A. Soderblom, B. Stiles, E. R. Stofan, S. Vetrella, R. West, C. A. Wood, L. Wye, H. Zebker, G. Alberti, E. Karkoschka, B. Rizk, E. McFarlane, C. See, B. Kazeminejad
The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe
At the beginning of 2006, the U.S. Geological Survey (USGS) Earthquake Hazards Program (EHP) introduced a new automated Earthquake Notification Service (ENS) to take the place of the National Earthquake Information Center (NEIC) "Bigquake" system and the various other individual EHP e-mail list-servers for separate regions in the United States. These included northern California...
Authors
Lisa A. Wald, David J. Wald, Stan Schwarz, Bruce Presgrave, Paul S. Earle, Eric Martinez, David Oppenheimer
Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits
Hydrothermal alteration at Mount Rainier waxed and waned over the 500,000-year episodic growth of the edifice. Hydrothermal minerals and their stable-isotope compositions in samples collected from outcrop and as clasts from Holocene debris-flow deposits identify three distinct hypogene argillic/advanced argillic hydrothermal environments: magmatic-hydrothermal, steam-heated, and magmatic...
Authors
D. A. John, T. W. Sisson, G. N. Breit, R. O. Rye, J.W. Vallance
Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades
Medicine Lake Volcano (MLV), located in the southern Cascades ∼ 55 km east-northeast of contemporaneous Mount Shasta, has been found by exploratory geothermal drilling to have a surprisingly silicic core mantled by mafic lavas. This unexpected result is very different from the long-held view derived from previous mapping of exposed geology that MLV is a dominantly basaltic shield volcano...
Authors
Julie M. Donnelly-Nolan, Timothy L. Grove, M. A. Lanphere, Duane E. Champion, David W. Ramsey
Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska
Gareloi Volcano (178.794 degrees W and 51.790 degrees N) is located on Gareloi Island in the Delarof Islands group of the Aleutian Islands, about 2,000 kilometers west-southwest of Anchorage and about 150 kilometers west of Adak, the westernmost community in Alaska. This small (about 8x10 kilometer) volcano has been one of the most active in the Aleutians since its discovery by the...
Authors
Michelle L. Coombs, Robert G. McGimsey, Brandon L. Browne
The 8 October 2006 Md 4.5 Cowlitz chimneys earthquake in Mount Rainier National Park The 8 October 2006 Md 4.5 Cowlitz chimneys earthquake in Mount Rainier National Park
An Md 4.5 earthquake located ∼12 km east of Mount Rainier occurred on 8 October 2006 at 02:48 UTC (figure 1). Although not large enough to be damaging or of major tectonic significance, a summary description of the earthquake is warranted because of its proximity to Mount Rainier, and because earthquakes of Md ≥ 4.5 are relatively rare in this region. Previous events of Md ≥ 4.5 have...
Authors
J. Renate Hartog, Joan S. Gomberg, Seth C. Moran, Amy K. Wright, Karen L. Meagher
Hematite spherules at Meridiani: results from MI, Mini-TES, and Pancam Hematite spherules at Meridiani: results from MI, Mini-TES, and Pancam
We report on observations of hematite‐bearing spherules at Meridiani Planum made using the Microscopic Imager (MI), Mini‐Thermal Emission Spectrometer (Mini‐TES), and Panoramic Camera (Pancam) instruments on the Mars Exploration Rover Opportunity. Spherules were observed on soil surfaces and in outcrop rocks, both on undisturbed surfaces and in abraded surfaces ground using the Rock...
Authors
W. M. Calvin, J.D. Shoffner, J. R. Johnson, A.H. Knoll, J.M. Pocock, S. W. Squyres, C.M. Weitz, R. E. Arvidson, J.F. Bell, P. R. Christensen, P. A. de Souza, W. H. Farrand, T.D. Glotch, Kenneth E. Herkenhoff, B.L. Jolliff, A.T. Knudson, S. M. McLennan, A.D. Rogers, S.D. Thompson
Three-dimensional P-wave velocity structure and precise earthquake relocation at Great Sitkin Volcano, Alaska Three-dimensional P-wave velocity structure and precise earthquake relocation at Great Sitkin Volcano, Alaska
Waveform cross-correlation with bispectrum verification is combined with double-difference tomography to increase the precision of earthquake locations and constrain regional 3D P-wave velocity heterogeneity at Great Sitkin volcano, Alaska. From 1999 through 2005, the Alaska Volcano Observatory (AVO) recorded ∼1700 earthquakes in the vicinity of Great Sitkin, including two ML 4.3...
Authors
Jeremy Pesicek, Clifford H. Thurber, Heather R. DeShon, Stephanie G. Prejean, Haijiang Zhang
EAARL coastal topography — Fire Island National Seashore 2007 EAARL coastal topography — Fire Island National Seashore 2007
These remotely sensed, geographically referenced elevation measurements of Lidar-derived first surface (FS) and bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Northeast Coastal and Barrier Network, Kingston, RI; and the National...
Authors
Amar Nayegandhi, John Brock, C. Wayne Wright, Sara Stevens, Xan Yates, Jamie M. Bonisteel
4D volcano gravimetry 4D volcano gravimetry
Time-dependent gravimetric measurements can detect subsurface processes long before magma flow leads to earthquakes or other eruption precursors. The ability of gravity measurements to detect subsurface mass flow is greatly enhanced if gravity measurements are analyzed and modeled with ground-deformation data. Obtaining the maximum information from microgravity studies requires careful...
Authors
Maurizio Battaglia, J. Gottsmann, D. Carbone, J. Fernandez
Eruption dynamics at Mount St. Helens imaged from broadband seismic waveforms: Interaction of the shallow magmatic and hydrothermal systems Eruption dynamics at Mount St. Helens imaged from broadband seismic waveforms: Interaction of the shallow magmatic and hydrothermal systems
The current eruption at Mount St. Helens is characterized by dome building and shallow, repetitive, long-period (LP) earthquakes. Waveform cross-correlation reveals remarkable similarity for a majority of the earthquakes over periods of several weeks. Stacked spectra of these events display multiple peaks between 0.5 and 2 Hz that are common to most stations. Lower-amplitude very-long...
Authors
G.P. Waite, B. A. Chouet, P.B. Dawson
Finite-fault analysis of the 2004 Parkfield, California, earthquake using Pnl waveforms Finite-fault analysis of the 2004 Parkfield, California, earthquake using Pnl waveforms
We apply a kinematic finite-fault inversion scheme to Pnl displacement waveforms recorded at 14 regional stations (Δ
Authors
C. Mendoza, S. Hartzell