Publications
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Submarine landslides Submarine landslides
Landslides are common on inclined areas of the seafloor, particularly in environments where weak geologic materials such as rapidly deposited, finegrained sediment or fractured rock are subjected to strong environmental stresses such as earthquakes, large storm waves, and high internal pore pressures. Submarine landslides can involve huge amounts of material and can move great distances...
Authors
M. A. Hampton, H.J. Lee, J. Locat
Debris flows and landslides resulting from the June 27, 1995, storm on the North Fork of the Moormons River, Shenandoah National Park, Virginia Debris flows and landslides resulting from the June 27, 1995, storm on the North Fork of the Moormons River, Shenandoah National Park, Virginia
No abstract available.
Authors
B. A. Morgan, G. F. Wieczorek
Geomagnetic storms, the Dst ring-current myth and lognormal distributions Geomagnetic storms, the Dst ring-current myth and lognormal distributions
The definition of geomagnetic storms dates back to the turn of the century when researchers recognized the unique shape of the H-component field change upon averaging storms recorded at low latitude observatories. A generally accepted modeling of the storm field sources as a magnetospheric ring current was settled about 30 years ago at the start of space exploration and the discovery of...
Authors
W.H. Campbell
Quake Forecasting- An Emerging Capability Quake Forecasting- An Emerging Capability
No abstract available.
Authors
Andrew Michael, Paul Reasenberg, Peter H. Stauffer, James W. Hendley
Landslides triggered by the 1994 Northridge, California, earthquake Landslides triggered by the 1994 Northridge, California, earthquake
The 17 January 1994 Northridge, California, earthquake (Mw = 6.7) triggered more than 11,000 landslides over an area of about 10,000 km2. Most of the landslides were concentrated in a 1000-km2 area that included the Santa Susana Mountains and the mountains north of the Santa Clara River valley. We mapped landslides triggered by the earthquake in the field and from 1:60,000-nominal-scale...
Authors
E. L. Harp, R.W. Jibson
Aeromagnetic survey over US to advance geomagnetic research Aeromagnetic survey over US to advance geomagnetic research
A proposed high-altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic-anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER-2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The...
Authors
T.G. Hildenbrand, R.J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
Site-response maps for the Los Angeles region based on earthquake ground motions Site-response maps for the Los Angeles region based on earthquake ground motions
Ground-motion records from aftershocks of the 1994 Northridge earthquake and main-shock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response in the urban Los Angeles, California, area. Two frequency bands are considered, 0.5-1.5 Hz and 2.0-6.0 Hz. Instrument characteristics prevented going to...
Authors
Stephen H. Hartzell, Stephen C. Harmsen, Arthur D. Frankel, David L. Carver, Edward Cranswick, Mark E. Meremonte, John A. Michael
The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics
The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036º N., long 121.883º W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip occurred on a dipping fault surface about 35...
Authors
Paul A. Spudich, Gregory C. Beroza, George Choy, John Boatwright, Stephen H. Hartzell, Gordon L. Stewart, Carlos Mendoza, Stephen Horton, John G. Anderson, Andres J. Mendez, Hiroo Kanamori, Kenji Satake, Michael Lisowski, Mark Hunter Murray, Jerry L. Svarc, Grant Marshall, Ross S. Stein, Karen McNally, Gerald W. Simila, Judy G. Brown, J.L. Nabelek, Ze’ev Reches, Mark D. Zoback, Jamison Steidl, Ralph J. Archuleta, Aaron A. Velasco, Thorne Lay, Jiajun Zhang, David J. Wald, Donald V. Helmberger, Thomas H. Heaton, Chesley R. Williams, Paul Segall, Francis T. Wu, Mingdong Wu, J.W. Rudnicki
Use of landslides for paleoseismic analysis Use of landslides for paleoseismic analysis
In many environments, landslides preserved in the geologic record can be analyzed to determine the likelihood of seismic triggering. If evidence indicates that a seismic origin is likely for a landslide or group of landslides, and if the landslides can be dated, then a paleo-earthquake can be inferred, and some of its characteristics can be estimated. Such paleoseismic landslide studies...
Authors
R.W. Jibson
Aeromagnetic survey over U.S. to advance geomagnetic research Aeromagnetic survey over U.S. to advance geomagnetic research
A proposed high‐altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic‐anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER‐2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The...
Authors
T.G. Hildenbrand, R.J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
The Springdale, Utah, landslide: An extraordinary event The Springdale, Utah, landslide: An extraordinary event
The most dramatic geologic effect of the M-5.7 St. George, Utah earthquake of 2 September 1992 was the triggering of the 14,000,000-m3 Springdale, Utah landslide. The roughly 10 m of landslide movement destroyed three houses, threatened several condominiums, disrupted utility lines, and temporarily closed the southwest entrance to Zion National Park. The seismic triggering of this...
Authors
R.W. Jibson, E. L. Harp
Preliminary inventory of debris-flow and flooding effects of the June 27, 1995, storm in Madison County, Virginia showing time sequence of positions of storm-cell center Preliminary inventory of debris-flow and flooding effects of the June 27, 1995, storm in Madison County, Virginia showing time sequence of positions of storm-cell center
No abstract available.
Authors
G. F. Wieczorek, B. A. Morgan, R. H. Campbell, R. C. Orndorff, W.C. Burton, C.S. Southworth, J. A. Smith