Publications
Filter Total Items: 7611
Non-double-couple microearthquakes at Long Valley caldera, California, provide evidence for hydraulic fracturing Non-double-couple microearthquakes at Long Valley caldera, California, provide evidence for hydraulic fracturing
Most of 26 small (0.4≲M≲3.1) microearthquakes at Long Valley caldera in mid-1997, analyzed using data from a dense temporary network of 69 digital three-component seismometers, have significantly non-double-couple focal mechanisms, inconsistent with simple shear faulting. We determined their mechanisms by inverting P- and S-wave polarities and amplitude ratios using linear-programming...
Authors
G.R. Foulger, B.R. Julian, D.P. Hill, A.D. Pitt, P.E. Malin, E. Shalev
Coastal vulnerability assessment of Cumberland Island National Seashore (CUIS) to sea-level rise Coastal vulnerability assessment of Cumberland Island National Seashore (CUIS) to sea-level rise
A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise within Cumberland Island National Seashore in Georgia. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, historical shoreline change rates...
Authors
Elizabeth A. Pendleton, E. Robert Thieler, S. Jeffress Williams
Shear- and compressional- wave velocity measurements from two 150-m-deep boreholes in Seattle, Washington, USA Shear- and compressional- wave velocity measurements from two 150-m-deep boreholes in Seattle, Washington, USA
No abstract available.
Authors
Jack K. Odum, William J. Stephenson, Kathy Goetz-Troost, David M. Worley, Arthur D. Frankel, Robert A. Williams, Jake Fryer
Pancam multispectral imaging results from the opportunity Rover at Meridiani Planum 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...
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
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
Recalculated probability of M ≥ 7 earthquakes beneath the Sea of Marmara, Turkey Recalculated probability of M ≥ 7 earthquakes beneath the Sea of Marmara, Turkey
New earthquake probability calculations are made for the Sea of Marmara region and the city of Istanbul, providing a revised forecast and an evaluation of time-dependent interaction techniques. Calculations incorporate newly obtained bathymetric images of the North Anatolian fault beneath the Sea of Marmara [Le Pichon et al., 2001; Armijo et al., 2002]. Newly interpreted fault...
Authors
T. Parsons
Landslides mapped using LIDAR imagery, Seattle, Washington Landslides mapped using LIDAR imagery, Seattle, Washington
No abstract available.
Authors
William H. Schulz
Hawaiian submarine manganese-iron oxide crusts - A dating tool? Hawaiian submarine manganese-iron oxide crusts - A dating tool?
Black manganese-iron oxide crusts form on most exposed rock on the ocean floor. Such crusts are well developed on the steep lava slopes of the Hawaiian Ridge and have been sampled during dredging and submersible dives. The crusts also occur on fragments detached from bedrock by mass wasting, on submerged coral reefs, and on poorly lithified sedimentary rocks. The thickness of the crusts...
Authors
J.G. Moore, D.A. Clague
Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion
The Taupo Volcanic Zone (TVZ), New Zealand is a region characterized by very high magma eruption rates and extremely high heat flow, which is manifest in high-temperature geothermal waters. The shear wave velocity structure across the region is inferred using non-linear inversion of receiver functions, which were derived from teleseismic earthquake data. Results from the non-linear...
Authors
S. Bannister, C.J. Bryan, H.M. Bibby
Mapping recent lava flows at Westdahl Volcano, Alaska, using radar and optical satellite imagery Mapping recent lava flows at Westdahl Volcano, Alaska, using radar and optical satellite imagery
Field mapping of young lava flows at Aleutian volcanoes is logistically difficult, and the utility of optical images from aircraft or satellites for this purpose is greatly reduced by persistent cloud cover. These factors have hampered earlier estimates of the areas and volumes of three young lava flows at Westdahl Volcano, including its most recent (1991–1992) flow. We combined...
Authors
Z. Lu, Russ Rykhus, Timothy Masterlark, K.G. Dean
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
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