Publications
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Ground motion in Anchorage, Alaska, from the 2002 Denali fault earthquake: Site response and displacement pulses Ground motion in Anchorage, Alaska, from the 2002 Denali fault earthquake: Site response and displacement pulses
Data from the 2002 Denali fault earthquake recorded at 26 sites in and near Anchorage, Alaska, show a number of systematic features important in studies of site response and in constructing long-period spectra for use in earthquake engineering. The data demonstrate that National Earthquake Hazards Reduction Program (NEHRP) site classes are a useful way of grouping stations according to...
Authors
D.M. Boore
Probabilistic seismic hazard analysis for Sumatra, Indonesia and across the Southern Malaysian Peninsula Probabilistic seismic hazard analysis for Sumatra, Indonesia and across the Southern Malaysian Peninsula
The ground motion hazard for Sumatra and the Malaysian peninsula is calculated in a probabilistic framework, using procedures developed for the US National Seismic Hazard Maps. We constructed regional earthquake source models and used standard published and modified attenuation equations to calculate peak ground acceleration at 2% and 10% probability of exceedance in 50 years for rock...
Authors
M.D. Petersen, J. Dewey, S. Hartzell, C. Mueller, S. Harmsen, A.D. Frankel, K. Rukstales
Quantifying probabilities of volcanic events: The example of volcanic hazard at Mount Vesuvius Quantifying probabilities of volcanic events: The example of volcanic hazard at Mount Vesuvius
We describe an event tree scheme to quantitatively estimate both long- and short-term volcanic hazard. The procedure is based on a Bayesian approach that produces a probability estimation of any possible event in which we are interested and can make use of all available information including theoretical models, historical and geological data, and monitoring observations. The main steps...
Authors
W. Marzocchi, L. Sandri, P. Gasparini, C. Newhall, Enzo Boschi
Seismic velocity models for the Denali fault zone along the Richardson Highway, Alaska Seismic velocity models for the Denali fault zone along the Richardson Highway, Alaska
Crustal-scale seismic-velocity models across the Denali fault zone along the Richardson Highway show a 50-km-thick crust, a near vertical fault trace, and a 5-km-wide damage zone associated with the fault near Trans-Alaska Pipeline Pump Station 10, which provided the closest strong ground motion recordings of the 2002 Denali fault earthquake. We compare models, derived from seismic...
Authors
T.M. Brocher, G. S. Fuis, W. J. Lutter, N.I. Christensen, N. A. Ratchkovski
In situ evidence for an ancient aqueous environment at Meridiani Planum, Mars In situ evidence for an ancient aqueous environment at Meridiani Planum, Mars
Sedimentary rocks at Eagle crater in Meridiani Planum are composed of fine-grained siliciclastic materials derived from weathering of basaltic rocks, sulfate minerals (including magnesium sulfate and jarosite) that constitute several tens of percent of the rock by weight, and hematite. Cross-stratification observed in rock outcrops indicates eolian and aqueous transport. Diagenetic...
Authors
S. W. Squyres, J.P. Grotzinger, R. E. Arvidson, J.F. Bell, W. Calvin, P. R. Christensen, B. C. Clark, J.A. Crisp, W. H. Farrand, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, A.H. Knoll, S. M. McLennan, H.Y. McSween, R.V. Morris, J. W. Rice, R. Rieder, Laurence A. Soderblom
Transient volcano deformation sources imaged with interferometric synthetic aperture radar: Application to Seguam Island, Alaska Transient volcano deformation sources imaged with interferometric synthetic aperture radar: Application to Seguam Island, Alaska
Thirty interferometric synthetic aperture radar (InSAR) images, spanning various intervals during 1992–2000, document coeruptive and posteruptive deformation of the 1992–1993 eruption on Seguam Island, Alaska. A procedure that combines standard damped least squares inverse methods and collective surfaces, identifies three dominant amorphous clusters of deformation point sources...
Authors
Timothy Masterlark, Zhong Lu
Observed and simulated ground motions in the San Bernardino basin region for the Hector Mine, California, earthquake Observed and simulated ground motions in the San Bernardino basin region for the Hector Mine, California, earthquake
During the MW 7.1 Hector Mine earthquake, peak ground velocities recorded at sites in the central San Bernardino basin region were up to 2 times larger and had significantly longer durations of strong shaking than sites just outside the basin. To better understand the effects of 3D structure on the long-period ground-motion response in this region, we have performed finite-difference...
Authors
R.W. Graves, D.J. Wald
Basaltic rocks analyzed by the Spirit rover in Gusev crater Basaltic rocks analyzed by the Spirit rover in Gusev crater
The Spirit landing site in Gusev Crater on Mars contains dark, fine-grained, vesicular rocks interpreted as lavas. Pancam and Mini–Thermal Emission Spectrometer (Mini-TES) spectra suggest that all of these rocks are similar but have variable coatings and dust mantles. Magnified images of brushed and abraded rock surfaces show alteration rinds and veins. Rock interiors contain ≤25%...
Authors
H.Y. McSween, R. E. Arvidson, J.F. Bell, D. Blaney, N.A. Cabrol, P. R. Christensen, B. C. Clark, J.A. Crisp, L.S. Crumpler, D.J. Des Marias, J.D. Farmer, Ralf Gellert, A. Ghosh, S. Gorevan, T. Graff, J. Grant, L.A. Haskin, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, G. Klingelhoefer, A.T. Knudson, S. McLennan, K.A. Milam, J.E. Moersch, R.V. Morris, R. Rieder, S. W. Ruff, P.A. De Souza, S. W. Squyres, H. Wanke, A. Wang, M.B. Wyatt, A. Yen, J. Zipfel
Time-series photographs of the sea floor in western Massachusetts Bay: June 1997 to June 1998 Time-series photographs of the sea floor in western Massachusetts Bay: June 1997 to June 1998
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 June 1997 through June 1998. Site A is approximately 1 km south of an ocean outfall that began discharging treated sewage effluent from the Boston metropolitan area into Massachusetts Bay in...
Authors
Bradford Butman, P. Soupy Alexander, Michael H. Bothner
Imaging Borrelly Imaging Borrelly
The nucleus, coma, and dust jets of short-period Comet 19P/Borrelly were imaged from the Deep Space 1 spacecraft during its close flyby in September 2001. A prominent jet dominated the near-nucleus coma and emanated roughly normal to the long axis of nucleus from a broad central cavity. We show it to have remained fixed in position for more than 34 hr, much longer than the 26-hr rotation...
Authors
Laurence A. Soderblom, D. C. Boice, D.T. Britt, R. H. Brown, B. J. Buratti, Randolph L. Kirk, M. Lee, R.M. Nelson, J. Oberst, B.R. Sandel, S. A. Stern, N. Thomas, R.V. Yelle
Local amplification of seismic waves from the Denali earthquake and damaging seiches in Lake Union, Seattle, Washington Local amplification of seismic waves from the Denali earthquake and damaging seiches in Lake Union, Seattle, Washington
The Mw7.9 Denali, Alaska earthquake of 3 November, 2002, caused minor damage to at least 20 houseboats in Seattle, Washington by initiating water waves in Lake Union. These water waves were likely initiated during the large amplitude seismic surface waves from this earthquake. Maps of spectral amplification recorded during the Denali earthquake on the Pacific Northwest Seismic Network...
Authors
A. Barberopoulou, A. Qamar, T. L. Pratt, K. C. Creager, W. P. Steele
Short-wavelength infrared (1.3-2.6 μm) observations of the nucleus of Comet 19P/Borrelly Short-wavelength infrared (1.3-2.6 μm) observations of the nucleus of Comet 19P/Borrelly
During the last two minutes before closest approach of Deep Space 1 to Comet 19P/Borrelly, a long exposure was made with the short-wavelength infrared (SWIR) imaging spectrometer. The observation yielded 46 spectra covering 1.3–2.6 μm; the footprint of each spectrum was ∼160 m × width of the nucleus. Borrelly's highly variegated and extremely dark 8-km-long nucleus exhibits a strong red...
Authors
Laurence A. Soderblom, D.T. Britt, R. H. Brown, B. J. Buratti, Randolph L. Kirk, T.C. Owen, R.V. Yelle