Publications

Events such as hurricanes, earthquakes, floods, tsunamis, volcanic eruptions, and tornadoes are natural disasters because they negatively impact society, and so they must be measured and understood in human-related terms. At the U.S. Geological Survey, we have developed a new method to examine fatality and dollar-loss data, and to make probabilistic estimates of the frequency and...

We provide an overview of new ground-motion relations for eastern North America (ENA) developed over the last five years. The empirical-stochastic relations of Atkinson and Boore (1995) are compared to relations developed by the Electric Power Research Institute (EPRI, 1993; also Toro et al., 1994), Frankel et al. (1996), and the consensus ENA ground-motion values as reported by SSHAC...

No abstract available.

A severe storm on June 27, 1995 triggered hundreds of rock, debris and soil slides from the steep hillsides of Madison County, Virginia. Most of these transformed into debris flows that inundated areas downslope causing damage to structures, roads, utilities, livestock and crops. This report contains an analysis of areas susceptible to debris flows including an examination of source...

No abstract available.

No abstract available.

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This report constitutes the requested 'Options Document'. This report considers three options. Option I assumes a constant level of financial support for Operating Expenses (OE) with not additional personnel support. Option II assumes a slight increase in OE support of $150K for FY 99 and beyond. Option III considers the role that a NSMP must play if the nation's urgent need to record...

Geomagnetic storms, induced by solar activity, pose significant hazards to satellites, electrical power distribution systems, radio communications, navigation, and geophysical surveys. Strong storms can expose astronauts and crews of high-flying aircraft to dangerous levels of radiation. Economic losses from recent geomagnetic storms have run into hundreds of millions of dollars. With...

The Cascade Range of the Pacific Northwest has more than a dozen potentially active volcanoes. Cascade volcanoes tend to erupt explosively, and on average two eruptions occur per century—the most recent were at Mount St. Helens, Washington (1980–86 and 2004–8), and Lassen Peak, California (1914–17). To help protect the Pacific Northwest’s rapidly expanding population, USGS scientists at...

The common statistical practice of dividing a range of probabilities into equal probability intervals may not result in useful landslide-hazard map units for areas populated by equal-area cells, each of which has a unique probability. Most hazard map areas contain very large numbers of cells having low probability of failure, and as probability increases, the number of cells decreases in...

Interactions of solid and fluid constituents produce the unique style of motion that typifies debris flows. To simulate this motion, a new hydraulic model represents debris flows as deforming masses of granular solids variably liquefied by viscous pore fluid. The momentum equation of the model describes how internal and boundary forces change as coarse-grained surge heads dominated by...