Publications
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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 to have b
Authors
G. Carver, G. 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
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 brief pause in
Authors
P. Dawson, D. Whilldin, B. Chouet
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 of this e
Authors
D. D. Oglesby, Douglas S. Dreger, R. A. Harris, N. Ratchkovski, R. Hansen
Radiated energy and the rupture process of the Denali fault earthquake sequence of 2002 from broadband teleseismic body waves
Displacement, velocity, and velocity-squared records of P and SH body waves recorded at teleseismic distances are analyzed to determine the rupture characteristics of the Denali fault, Alaska, earthquake of 3 November 2002 (MW 7.9, Me 8.1). Three episodes of rupture can be identified from broadband (∼0.1–5.0 Hz) waveforms. The Denali fault earthquake started as a MW 7.3 thrust event. Subsequent r
Authors
G. L. Choy, J. Boatwright
Rupture process of the M 7.9 Denali fault, Alaska, earthquake: Subevents, directivity, and scaling of high-frequency ground motions
Displacement waveforms and high-frequency acceleration envelopes from stations at distances of 3-300 km were inverted to determine the source process of the M 7.9 Denali fault earthquake. Fitting the initial portion of the displacement waveforms indicates that the earthquake started with an oblique thrust subevent (subevent # 1) with an east-west-striking, north-dipping nodal plane consistent with
Authors
A. Frankel
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 update it wit
Authors
Patricia A. McCrory, J. Luke Blair, David H. Oppenheimer, Stephen R. Walter
Emergency assessment of debris-flow hazards from basins burned by the Cedar and Paradise Fires of 2003, southern California
These maps present preliminary assessments of the probability of debris-flow activity and estimates of peak discharges that can potentially be generated by debris flows issuing from basins burned by the Cedar and Paradise Fires of October 2003 in southern California in response to 25-year, 10-year, and 2-year recurrence, 1-hour duration rain storms. The probability maps are based on the applicatio
Authors
Susan H. Cannon, Joseph E. Gartner, Michael G. Rupert, John A. Michael
Landslides mapped using LIDAR imagery, Seattle, Washington
No abstract available.
Authors
William H. Schulz
The opportunity Rover's Athena science investigation at Meridiani Planum, Mars
The Mars Exploration Rover Opportunity has investigated the landing site in Eagle crater and the nearby plains within Meridiani Planum. The soils consist of fine-grained basaltic sand and a surface lag of hematite-rich spherules, spherule fragments, and other granules. Wind ripples are common. Underlying the thin soil layer, and exposed within small impact craters and troughs, are flat-lying sedim
Authors
S. W. Squyres, R. E. Arvidson, J.F. Bell, J. Brückner, 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.H. 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
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 features includ
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
Pancam multispectral imaging results from the opportunity Rover at Meridiani Planum
Panoramic Camera (Pancam) images from Meridiani Planum reveal a low-albedo, generally flat, and relatively rock-free surface. Within and around impact craters and fractures, laminated outcrop rocks with higher albedo are observed. Fine-grained materials include dark sand, bright ferric iron-rich dust, angular rock clasts, and millimeter-size spheroidal granules that are eroding out of the laminate
Authors
J.F. Bell, S. W. Squyres, R. E. Arvidson, H.M. Arneson, D. Bass, W. Calvin, W. H. Farrand, W. Goetz, M. Golombek, R. Greeley, J. Grotzinger, E. Guinness, A. G. Hayes, M.Y.H. Hubbard, Kenneth E. Herkenhoff, M. J. Johnson, J. R. Johnson, J. Joseph, K.M. Kinch, M.T. Lemmon, R. Li, M.B. Madsen, J.N. Maki, M. Malin, E. McCartney, S. McLennan, H.Y. McSween, D. W. Ming, R.V. Morris, E.Z. Noe Dobrea, T. J. Parker, J. Proton, J. W. Rice, F. Seelos, J.M. Soderblom, Laurence A. Soderblom, J. N. Sohl-Dickstein, R.J. Sullivan, C.M. Weitz, M.J. Wolff
Soils of eagle crater and Meridiani Planum at the opportunity Rover landing site
The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts. Two types of vesicular clasts may represent
Authors
Laurence A. Soderblom, R. C. Anderson, R. E. Arvidson, J.F. Bell, N.A. Cabrol, W. Calvin, P. R. Christensen, B. C. Clark, T. Economou, B.L. Ehlmann, W. H. Farrand, D. Fike, Ralf Gellert, T.D. Glotch, M.P. Golombek, R. Greeley, J.P. Grotzinger, Kenneth E. Herkenhoff, D.J. Jerolmack, J. R. Johnson, B. Jolliff, C. Klingelhofer, A.H. Knoll, Z.A. Learner, R. Li, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, R.V. Morris, J. W. Rice, L. Richter, R. Rieder, D. Rodionov, C. Schroder, F.P. Seelos, J.M. Soderblom, S. W. Squyres, R. Sullivan, W.A. Watters, C.M. Weitz, M.B. Wyatt, A. Yen, J. Zipfel