Publications
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Landslides triggered by the 2002 Denali fault, Alaska, earthquake and the inferred nature of the strong shaking Landslides triggered by the 2002 Denali fault, Alaska, earthquake and the inferred nature of the strong shaking
The 2002 M7.9 Denali fault, Alaska, earthquake triggered thousands of landslides, primarily rock falls and rock slides, that ranged in volume from rock falls of a few cubic meters to rock avalanches having volumes as great as 15 ?? 106 m3. The pattern of landsliding was unusual; the number of slides was less than expected for an earthquake of this magnitude, and the landslides were...
Authors
R.W. Jibson, E. L. Harp, W. Schulz, D. K. Keefer
Crustal structure of the northern margin of the eastern Tien Shan, China, and its tectonic implications for the 1906 M~7.7 Manas earthquake Crustal structure of the northern margin of the eastern Tien Shan, China, and its tectonic implications for the 1906 M~7.7 Manas earthquake
The Tien Shan orogenic belt is the most active intracontinental mountain belt in the world. We describe an 86-km-long N–S-trending deep seismic reflection profile (which passes through the southern Junggar basin) located on the northeastern Tien Shan piedmont. Two distinct anticlines beneath the northern margin of the Tien Shan are clearly imaged in the seismic section. In addition, we...
Authors
Chun-Yong Wang, Zhu-En Yang, Hai Luo, Walter D. Mooney
Community preparedness for lava flows from Mauna Loa and Hualālai volcanoes, Kona, Hawai'i Community preparedness for lava flows from Mauna Loa and Hualālai volcanoes, Kona, Hawai'i
Lava flows from Mauna Loa and Hualālai volcanoes are a major volcanic hazard that could impact the western portion of the island of Hawai'i (e.g., Kona). The most recent eruptions of these two volcanoes to affect Kona occurred in A.D. 1950 and ca. 1800, respectively. In contrast, in eastern Hawai'i, eruptions of neighboring Kilauea volcano have occurred frequently since 1955, and...
Authors
Chris E. Gregg, Bruce F. Houghton, Douglas Paton, Donald A. Swanson, David M. Johnston
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
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
The Spirit Rover's Athena science investigation at Gusev crater, Mars The Spirit Rover's Athena science investigation at Gusev crater, Mars
The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. Gusev is hypothesized to be the site of a former take, but no clear evidence for lacustrine sedimentation has been found to date. Instead, the dominant lithology is basalt, and the dominant geologic processes are impact events and eolian transport. Many rocks...
Authors
S. W. Squyres, R. E. Arvidson, J.F. Bell, J. Bruckner, N.A. Cabrol, W. Calvin, M. H. Carr, P. R. Christensen, B. C. Clark, L. Crumpler, D.J. Des Marais, C. D'Uston, T. Economou, J. Farmer, W. Farrand, W. Folkner, M. Golombek, S. Gorevan, J. A. Grant, R. Greeley, J. Grotzinger, L. Haskin, Kenneth E. Herkenhoff, S. Hviid, J. Johnson, G. Klingelhofer, A. Knoll, G. Landis, M. Lemmon, R. Li, M.B. Madsen, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, J. Moersch, R.V. Morris, T. Parker, J. W. Rice, L. Richter, R. Rieder, M. Sims, M. Smith, P. Smith, Laurence A. Soderblom, R. Sullivan, H. Wanke, T. Wdowiak, M. Wolff, A. Yen
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
Geochemical constraints on possible subduction components in lavas of Mayon and Taal Volcanoes, Southern Luzon, Philippines Geochemical constraints on possible subduction components in lavas of Mayon and Taal Volcanoes, Southern Luzon, Philippines
Mayon is the most active volcano along the east margin of southern Luzon, Philippines. Petrographic and major element data indicate that Mayon has produced a basaltic to andesitic lava series by fractional crystallization and magma mixing. Trace element data indicate that the parental basalts came from a heterogeneous mantle source. The unmodified composition of the mantle wedge is...
Authors
P.R. Castillo, C. G. Newhall
Prediction of nonlinear soil effects Prediction of nonlinear soil effects
Mathematical models of soil nonlinearity in common use and recently developed nonlinear codes compared to investigate the range of their predictions. We consider equivalent linear formulations with and without frequency-dependent moduli and damping ratios and nonlinear formulations for total and effective stress. Average velocity profiles to 150 m depth with midrange National Earthquake...
Authors
S. Hartzell, L.F. Bonilla, R. A. Williams
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
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
Application of near real-time radial semblance to locate the shallow magmatic conduit at Kilauea Volcano, Hawaii Application of near real-time radial semblance to locate the shallow magmatic conduit at Kilauea Volcano, Hawaii
Radial Semblance is applied to broadband seismic network data to provide source locations of Very-Long-Period (VLP) seismic energy in near real time. With an efficient algorithm and adequate network coverage, accurate source locations of VLP energy are derived to quickly locate the shallow magmatic conduit system at Kilauea Volcano, Hawaii. During a restart in magma flow following a...
Authors
P. Dawson, D. Whilldin, B. Chouet