Publications

A catastrophic rainstorm in central California on January 3-5,1982, dropped as much as half the mean annual precipitation within a period of about 32 hours, triggering landslides and floods throughout 10 counties in the vicinity of the San Francisco Bay. More than 18,000 of the slides induced by the storm transformed into debris flows that swept down hillslopes or drainages with little warning. De

Geological mapping and photointerpretation of side-looking airborne radar images and color-infrared aerial photographs reveal two large Quaternary landslides in the Valley and Ridge province of the central Appalachians near Petersburg, W. Va. The Elkhorn Mountain rock avalanche occurs on the thrust-faulted northwestern flank of the Elkhorn Mountain anticlinorium. A minimum of 7 × 106 m3 of quartzi

Topography of various types and scales can be fingerprinted by computer analysis of altitude matrices (digital elevation models, or DEMs). The critical analytic tool is the geometric signature, a set of measures that describes topographic form well enough to distinguish among geomorphically disparate landscapes. Different surficial processes create topography with diagnostic forms that are recogni

During the first five days of November 1985, a low-pressure system in the Ohio River valley combined with a low-pressure system referred to as Tropical Storm Juan to produce heavy rainfall in the Potomac, James, and Rappahannock River basins. Severe flooding accompanied the rainfall; 43 lives were lost and the flood was estimated to be the most expensive natural disaster of 1985 in the United Stat

No abstract available.

A system for forecasting landslides during major storms has been developed for the San Francisco Bay area by the U.S Geological Survey and was successfully tested during heavy storms in the bay area during February 1986. Based on the forecasts provided by the USGS, the National Weather Service (NWS) included landslide warnings in its regular weather forecasts or in special weather statements trans

Landslides historically have caused severe erosion problems in the Xiao River drainage region of northeastern Yunnan Province, China, that hence resulted in serious economic and social consequences. Owing to monsoonal storms of high rainfall intensity, the erosion potential is high in this mountainous, seismically active region. Landslides transported large quantities of materials into the ravines

No abstract available.

A real-time system for issuing warnings of landslides during major storms is being developed for the San Francisco Bay region, California. The system is based on empirical and theoretical relations between rainfall and landslide initiation, geologic determination of areas susceptible to landslides, real-time monitoring of a regional network of telemetering rain gages, and National Weather Service

Simple ground-water flow analyses can clarify complex empirical relations between rainfall and landslide motion. Here we present detailed data on rainfall, ground-water flow, and repetitive seasonal motion that occurred from 1982 to 1985 at Minor Creek landslide in northwestern California, and we interpret these data in the context of physically based theories. We find that landslide motion is clo

No abstract available.

The slopes above streams and rivers are subjected to a variety of processes that cause them to recede and retreat from the river or stream channel. These processes, collectively called mass wasting, can be classified according to rapidity of movement and according to the type of materials that are transported. Gravity is the force behind all such downslope movement. Factors that enable the force o