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The objective of this study is to develop a probabilistic model for earthquake occurrences with temporal and spatial memory. Stochastic processes are used to characterize both the spatial and temporal dependencies of seismic occurrences along a fault. Currently, only homogeneous space and time transitions are considered. The resulting process however...

Analyses of the surface effects of past underground coal mining in the Sheridan, Wyoming, area suggest that underground mining of strippable coal deposits may damage the environment more over long periods of time than would modern surface mining, provided proper restoration procedures are followed after surface mining. Subsidence depressions and...

PART A: A system of anticlines lies along the trend of the sinuous course of the Colorado River for a distance of 97 km in the central Grand Canyon. Similar anticlines occur in some perennially wet side canyons. The anticlines are most abundant and well developed along northeast-trending reaches of...

Hundreds of residential, commercial, and industrial structures in the Houston metropolitan area have sustained moderate to severe damage owing to their locations on or near active faults. Paved roads have been offset by faults at hundreds of locations, butted pipelines have been distorted by fault movements, and fault-induced gradient changes...

Displacement of the land surface by faulting is widespread in the Houston-Galveston region, an area which has undergone moderate to severe land subsidence associated with fluid withdrawal (principally water, and to a lesser extent, oil and gas). A causative link between subsidence and fluid extraction has been convincingly reported in...

The White River is the largest stream in the southeastern part of the Uinta Basin in Utah and Colorado. This map shows the changes that have occurred in the location of the main channel of the river from 1936 to 1974. The map indicated that certain reaches of the river...

Analyses of the surface effects of past underground coal mining in the western Powder River Basin suggest that underground mining of strippable coal deposits will damage the environment more over long periods of time than will modern surface mining, provided proper restoration procedures are followed after surface mining. Subsidence depressions...

Volcanic eruptions and related phenomena can be expected to occur in the Western United States, and in some places are potentially hazardous enough to be considered in longe-range land-use planning. But the immediate risk from volcanic hazards is low because eruptions are so infrequent in the conterminous United States that...

The Alaska earthquake of March 27, 1964, dramatically emphasized the need for engineering geologic studies of urban areas in seismically active regions. A reconnaissance study of the Ketchikan area in southeastern Alaska is part of a program to evaluate earthquake and other geologic hazards in most of the larger Alaska...

Geologic mapping at scale 1:24,000 of the Edna Mountain 15-minute quadrangle, Humboldt County, Nev., revealed two episodes of pre-Mesozoic deformation that are difficult to reconcile with either the Antler or the Sonoma orogeny. We believe that the older episode predated the Antler orogeny and may be as old as Late...

The thermal-feedback theory of mantle melting proposed by Shaw in 1969 is found to be quantitatively consistent with data pertaining to the evolution of the Hawaiian Ridge. Applicable rate factors are estimated from relations between lava volumes and position along the ridge given in this paper and the radio-metric age...

The great Alaska earthquake of March 27, 1964, brought into sharp focus the need for engineering geologic studies in seismically active regions. As a result, nine communities in southeastern Alaska were selected for reconnaissance investigations as an integral part of an overall program to evaluate earthquake and other geologic hazards...

A program to study the engineering geology of most of the larger Alaska coastal communities and to evaluate their earthquake and other geologic hazards was started promptly after the 1964 Alaska earthquake; this report is a product of that program. Field-study methods were largely reconnaissance, and thus the interpretations in...

The Baldwin Hills are located in the northwest part of the densely populated Los Angeles basin. They comprise one of several groups of isolated hills that extend along the northwest-trending Newport-Inglewood zone of folds and faults, a structural lineament identified with a series of very productive oil fields. In addition...

The Snake River basin, in southern Idaho, upstream from the mouth of the Powder River in Oregon, includes more than 50 percent of the land area and 65 percent of the total population of the State. More than 2.5 million acres of land is irrigated ; irrigation agriculture and industry...

The fluorspar deposits in the Northgate district, Jackson County, Colo., are among the largest in Western United States. The mines were operated intermittently during the 1920's and again during World War II, but production during these early periods of operation was not large. Mining was begun on a larger scale...

Through its Water Resources Division, the United States Geological Survey has become the major water-resources historian for the nation. The Geological Survey's collection of streamflow records in Kansas began on a very small scale in 1895 in response to some early irrigation interest, Since that time the program has grown,...

Many marine sedimentary black shale and phosphorite formations contain 0.01 to 0.02 percent uranium, and one, the alum shale of Sweden, contains as much as 0.5 percent. The published fact that uranium is already being recovered on a laboratory scale from Swedish deposits forcefully suggests that similar deposits in the...