Publications
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Morphometric properties of Martian volcanoes Morphometric properties of Martian volcanoes
Mars Orbiter Laser Altimeter (MOLA) data have been used to construct Digital Elevation Models (DEM) of the Martian volcanoes in order to determine height, flank slope, caldera depth, and volumes. Summit elevations range from 21.1 km to −0.5 km, and relief varies from 1.0 km to almost 22 km. Average flank slopes are in the range of
Authors
J. B. Plescia
High-rate real-time GPS network at Parkfield: Utility for detecting fault slip and seismic displacements High-rate real-time GPS network at Parkfield: Utility for detecting fault slip and seismic displacements
A network of 13 continuous GPS stations near Parkfield, California has been converted from 30 second to 1 second sampling with positions of the stations estimated in real-time relative to a master station. Most stations are near the trace of the San Andreas fault, which exhibits creep. The noise spectra of the instantaneous 1 Hz positions show flicker noise at high frequencies and change...
Authors
J. Langbein, Y. Bock
Wind-related processes detected by the Spirit rover at Gusev crater, Mars Wind-related processes detected by the Spirit rover at Gusev crater, Mars
Wind-abraded rocks, ripples, drifts, and other deposits of windblown sediments are seen at the Columbia Memorial Station where the Spirit rover landed. Orientations of these features suggest formative winds from the north-northwest, consistent with predictions from atmospheric models of afternoon winds in Gusev Crater. Cuttings from the rover Rock Abrasion Tool are asymmetrically...
Authors
R. Greeley, S. W. Squyres, R. E. Arvidson, P. Bartlett, J.F. Bell, D. Blaney, N.A. Cabrol, J. Farmer, B. Farrand, M.P. Golombek, S.P. Gorevan, J. A. Grant, A. F. C. Haldemann, Kenneth E. Herkenhoff, J. Johnson, G. Landis, M.B. Madsen, S.H. McLennan, J. Moersch, J. W. Rice, L. Richter, S. Ruff, R.J. Sullivan, S.D. Thompson, A. Wang, C.M. Weitz, P. Whelley
Surficial deposits at Gusev crater along Spirit Rover traverses Surficial deposits at Gusev crater along Spirit Rover traverses
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes. Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth. Some rocks have been textured and/or partially buried by windblown...
Authors
J. A. Grant, R. Arvidson, J.F. Bell, N.A. Cabrol, M. H. Carr, P. Christensen, L. Crumpler, D.J. Des Marais, B.L. Ehlmann, J. Farmer, M. Golombek, F.D. Grant, R. Greeley, Kenneth E. Herkenhoff, R. Li, H.Y. McSween, D. W. Ming, J. Moersch, J. W. Rice, S. Ruff, L. Richter, S. Squyres, R. Sullivan, C. Weitz
Reconciling different observations of the CO2 ice mass loading of the Martian north polar cap Reconciling different observations of the CO2 ice mass loading of the Martian north polar cap
The GRS measurements of the peak mass loading of the north polar CO2 ice cap on Mars are about 60% lower than those calculated from MGS TES radiation data and those inferred from the MOLA cap thicknesses. However, the GRS data provide the most accurate measurement of the mass loading. We show that the TES and MOLA data can be reconciled with the GRS data if (1) subsurface heat conduction...
Authors
Robert M. Haberle, Bridget Mattingly, Timothy N. Titus
Surface rupture on the Denali fault interpreted from tree damage during the 1912 Delta River Mw 7.2–7.4 earthquake: Implications for the 2002 Denali fault earthquake slip distribution Surface rupture on the Denali fault interpreted from tree damage during the 1912 Delta River Mw 7.2–7.4 earthquake: Implications for the 2002 Denali fault earthquake slip distribution
During the 3 November 2002 Denali fault earthquake, surface rupture propagated through a small, old-growth forest in the Delta River valley and damaged many trees growing on the fault. Damage was principally the result of fault offset of tree roots and tilting of trees. Some trees were split by surface faults that intersected the base of their trunks or large taproots. A few trees appear...
Authors
G. Carver, George Plafker, M. Metz, L. Cluff, B. Slemmons, E. Johnson, J. Roddick, S. Sorensen
Inverse kinematic and forward dynamic models of the 2002 Denali fault earthquake, Alaska Inverse kinematic and forward dynamic models of the 2002 Denali fault earthquake, Alaska
We perform inverse kinematic and forward dynamic models of the M 7.9 2002 Denali fault, Alaska, earthquake to shed light on the rupture process and dynamics of this event, which took place on a geometrically complex fault system in central Alaska. We use a combination of local seismic and Global Positioning System (GPS) data for our kinematic inversion and find that the slip distribution...
Authors
D. D. Oglesby, Douglas S. Dreger, R.A. Harris, N. Ratchkovski, R. Hansen
Surface rupture and slip distribution of the Denali and Totschunda faults in the 3 November 2002 M 7.9 earthquake, Alaska Surface rupture and slip distribution of the Denali and Totschunda faults in the 3 November 2002 M 7.9 earthquake, Alaska
The 3 November 2002 Denali fault, Alaska, earthquake resulted in 341 km of surface rupture on the Susitna Glacier, Denali, and Totschunda faults. The rupture proceeded from west to east and began with a 48-km-long break on the previously unknown Susitna Glacier thrust fault. Slip on this thrust averaged about 4 m (Crone et al., 2004). Next came the principal surface break, along 226 km...
Authors
Peter J. Haeussler, David P. Schwartz, Timothy E. Dawson, Heidi D. Stenner, James J. Lienkaemper, Brian L. Sherrod, Francesca R. Cinti, Paola Montone, Patricia Craw, Anthony J. Crone, Stephen F. Personius
Depth to the Juan de Fuca slab beneath the Cascadia subduction margin– A 3-D model for sorting earthquakes Depth to the Juan de Fuca slab beneath the Cascadia subduction margin– A 3-D model for sorting earthquakes
We present an updated model of the Juan de Fuca slab beneath southern British Columbia, Washington, Oregon, and northern California, and use this model to separate earthquakes occurring above and below the slab surface. The model is based on depth contours previously published by Fluck and others (1997). Our model attempts to rectify a number of shortcomings in the original model and...
Authors
Patricia A. McCrory, J. Luke Blair, David H. Oppenheimer, Stephen R. Walter
Seagrass communities of the Gulf Coast of Florida: status and ecology Seagrass communities of the Gulf Coast of Florida: status and ecology
No abstract available.
Authors
Clinton J. Dawes, Ronald C. Phillips, Gerold Morrison
Time-series photographs of the sea floor in western Massachusetts Bay: May 1999 to September 1999; May 2000 to September 2000; and October 2001 to February 2002 Time-series photographs of the sea floor in western Massachusetts Bay: May 1999 to September 1999; May 2000 to September 2000; and October 2001 to February 2002
This report presents time-series photographs of the sea floor obtained from an instrumented tripod deployed at Site A in western Massachusetts Bay (42° 22.6' N., 70° 47.0' W., 30 m water depth) from May 1999 to September 1999; May 2000 to September 2000; and October 2001 to February 2002. Site A is approximately 1 km south of an ocean outfall that began discharging treated sewage...
Authors
Bradford Butman, P. Soupy Alexander, Michael H. Bothner
The 26 May 1982 breakout flows derived from failure of a volcanic dam at El Chichón, Chiapas, Mexico The 26 May 1982 breakout flows derived from failure of a volcanic dam at El Chichón, Chiapas, Mexico
The eruptions of El Chichón between 28 March and 4 April 1982 produced a variety of pyroclastic deposits. The climactic phase, on 3 April at 07:35 (4 April at 01:35 GMT), destroyed the central andesitic dome and fed pyroclastic surges and flows that dammed nearby drainages, including the Magdalena River. By late April, a lake had formed, 4 km long and 300–400 m wide, containing a volume...
Authors
J.L. Macias, L. Capra, K. M. Scott, J.M. Espindola, A. Garcia-Palomo, J. E. Costa