Publications
Filter Total Items: 2189
The 2000 revision of the joint UK/US geomagnetic field models and an IGRF 2000 candidate model
The method of derivation of the joint UK/US spherical harmonic geomagnetic main-field and secular-variation models is presented. Early versions of these models, with the main field truncated at degree 10, are the UK/US candidates for the IGRF 2000 model. The main-field model describes the Earth’s magnetic field at the 2000.0 epoch, while the secular-variation model predicts the evolution of this f
Authors
S. Macmillan, J.M. Quinn
A method for producing digital probabilistic seismic landslide hazard maps
The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include: (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24 000-scale geologic mapping of the region, (4) extensive data on engineeri
Authors
R. W. Jibson, E. L. Harp, J. A. Michael
Debris-flow hazards in the Blue Ridge of central Virginia
The June 27, 1995, storm in Madison County, Virginia produced debris flows and floods that devastated a small (130 km 2 ) area of the Blue Ridge in the eastern United States. Although similar debris-flow inducing storm events may return only approximately once every two thousand years to the same given locale, these events affecting a similar small-sized area occur about every three years somewher
Authors
G. F. Wieczorek, B. A. Morgan, R. H. Campbell
Acute sensitivity of landslide rates to initial soil porosity
Some landslides move imperceptibly downslope, whereas others accelerate catastrophically. Experimental landslides triggered by rising pore water pressure moved at sharply contrasting rates due to small differences in initial porosity. Wet sandy soil with porosity of about 0.5 contracted during slope failure, partially liquefied, and accelerated within 1 second to speeds over I meter per second. Th
Authors
R. M. Iverson, M.E. Reid, N.R. Iverson, R.G. LaHusen, M. Logan, J.E. Mann, D.L. Brien
Variability of site response in Seattle, Washington
Ground motion from local earthquakes and the SHIPS (Seismic Hazards Investigation in Puget Sound) experiment is used to estimate site amplification factors in Seattle. Earthquake and SHIPS records are analyzed by two methods: (1) spectral ratios relative to a nearby site on Tertiary sandstone, and (2) a source/site spectral inversion technique. Our results show site amplifications between 3 and 4
Authors
S. Hartzell, D. Carver, E. Cranswick, A. Frankel
Statiscal analysis of an earthquake-induced landslide distribution - The 1989 Loma Prieta, California event
The 1989 Loma Prieta, California earthquake (moment magnitude, M=6.9) generated landslides throughout an area of about 15,000 km2 in central California. Most of these landslides occurred in an area of about 2000 km2 in the mountainous terrain around the epicenter, where they were mapped during field investigations immediately following the earthquake. The distribution of these landslides is invest
Authors
D. K. Keefer
Aerial-Photointerpretation of landslides along the Ohio and Mississippi rivers
A landslide inventory was conducted along the Ohio and Mississippi rivers in the New Madrid Seismic Zone of southern Illinois, between the towns of Olmsted and Chester, Illinois. Aerial photography and field reconnaissance identified 221 landslides of three types: rock/debris falls, block slides, and undifferentiated rotational/translational slides. Most of the landslides are small- to medium-size
Authors
Wen-June Su, Christopher Stohr
Potential seismic hazards and tectonics of the upper Cook Inlet basin, Alaska, based on analysis of Pliocene and younger deformation
The Cook Inlet basin is a northeast-trending forearc basin above the Aleutian subduction zone in southern Alaska. Folds in Cook Inlet are complex, discontinuous structures with variable shape and vergence that probably developed by right-transpressional deformation on oblique-slip faults extending downward into Mesozoic basement beneath the Tertiary basin. The most recent episode of deformation ma
Authors
Peter J. Haeussler, Ronald L. Bruhn, Thomas L. Pratt
Origin of the 17 July 1998 Papua New Guinea tsunami: Earthquake or landslide
The tsunami that struck Papua New Guinea on 17 July 1998 shortly after a Mw 7.0 earthquake (Figure 1) was one of the deadliest tsunamis in this century. At least 2,200 people died from this event, essentially destroying an entire generation in some communities. In the months following the tsunami, several international survey teams collected data in an attempt to better understand the cause of thi
Authors
E.L. Geist
Landslide triggering by rain infiltration
Landsliding in response to rainfall involves physical processes that operate on disparate timescales. Relationships between these timescales guide development of a mathematical model that uses reduced forms of Richards equation to evaluate effects of rainfall infiltration on landslide occurrence, timing, depth, and acceleration in diverse situations. The longest pertinent timescale is A/D0, where
Authors
Richard M. Iverson
Seasonal movement of the Slumgullion landslide as determined from GPS observations, July 1998-July 1999
No abstract available.
Authors
J. A. Coe, J. W. Godt, W. L. Ellis, W. Z. Savage, J. E. Savage, P. S. Powers, D. J. Varnes, P. Tachker
Preliminary interpretation of seasonal movement of the Slumgullion landslide as determined from GPS observations, July 1998-July 1999
No abstract available.
Authors
J. A. Coe, J. W. Godt, W. L. Ellis, W. Z. Savage, J. E. Savage, P. S. Powers, D. J. Varnes, P. Tachker