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C. Barry Raleigh

Publications and source records attributed to C. Barry Raleigh.

7 recordsLinked to original sources
USGS1981

Locations of geophysical instruments and survey points operated under the earthquake prediction element of the Earthquake Hazards Reduction Program 1981

This open-file report contains a series of maps and a list of the various geophysical monitoring sites (stations) operated by the U. S. Geological Survey and its contractors under the Earthquake Prediction Research Program. The purpose of this open file report is to provide information on type, location, frequency of measurement, and principal investigator for observations being made in California.

California↗
USGS1978

Facts relating to Well No. 5, Lease OCS-P 0234, Pitas Point Unit area, and the earthquake of August 13, 1978, Santa Barbara Channel, California

A build-up of pressures developed in an exploratory well being drilled in the Santa Barbara Channel during the period August 9 to 15, 1978. Nearly coincidentally, a sharp earthquake occurred 2 miles south of the city of Santa Barbara at 3:55 p.m. PDT on August 13, 1978. A task group was formed by the Director, Geological Survey, on August 14, mainly because of concern over the high down-hole pressures in the well. The charge to the task group was to study the situation fully in order that appropriate and immediate measures could be directed to protect against a fracturing of rock formations in the vicinity of the hole that might permit the escape of gas or oil to the surface. The task group was also asked to look into the possibility of any relationship between the well problems and the earthquake.

California↗
USGS1972

Earthquakes in the oil field at Rangely, Colorado

Seven years of seismic data recorded at the Uinta Basin Observatory were searched for earthquakes originating near an oil field at Rangely, Colorado, located 65 km ESE of the observatory. Changes in the number of earthquakes recorded per year appear to correlate with changes in the quantity of fluid injected per year. Between November 1962 and January 1970, 976 earthquakes were detected near the oil field by the UBO station; 320 earthquakes were larger than magnitude 1. Richter magnitudes are estimated from both S-wave and P-wave measurements and a method based on the duration of the seismic signal is used to estimate the magnitude of the larger shocks. The two largest shocks had magnitudes of 3.4 and 3.3. The total seismic energy released was l0 l7 ergs. During this same period the energy used for water injection, measured at the wellhead, was 10 21 ergs.

Colorado↗
USGS1969

Principal stress directions from plastic flow in crystals

Methods for determining orientations of principal stress axes in deformed rocks involve dynamic analysis of twin-gliding and of extinction bands produced by inhomogeneous translation gliding in crystals. The methods, beginning with Turner's (1953) technique for dynamic analysis of calcite twins, have been developed using as guides the results from experiments under controlled laboratory conditions. Structures induced by intragranular flow in calcite, dolomite, quartz, micas, orthopyroxenes, clinopyroxenes, olivine, and other common rock-forming materials, may now be used to derive orientations of principal stresses causing the deformation. The various methods, some new, are discussed in detail and examples of their application to tectonites are given. The usefulness of such studies is illustrated by evaluating the observed orientations of principal stresses around folds in light of new data from a theoretical analysis of large amplitude folding of viscous layers in a less viscous matrix. Other areas of research in structural geology in which these methods should prove useful have also been outlined.

Geological Society of America Bulletin↗