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A. Rapport

Publications and source records attributed to A. Rapport.

2 recordsLinked to original sources

Geotherm: the U.S. geological survey geothermal information system

GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey. Information in the system is available to the public on request. ?? 1983.

Computers & Geosciences

A preliminary study of the Coyote Lake earthquake of August 6, 1979, and its major aftershocks

The August 6, 1979 earthquake (magnitude 5.7 + 0.2) was located about 1 km east of the Calaveras fault trace near Coyote Lake, at a depth of about 10 km. The spatial distribution of the aftershocks in the first 15 days and the focal mechanism of the main shock and selected aftershocks suggest that faulting took place primarily to the southeast of the main shock along a 25-km segment of the Calaveras fault zone at a depth of 4 to 12 km. The motion was right-lateral strike-slip along a nearly vertical fault plane. Discontinuous surface rupture was observed along a 14.4-km length of the recently active trace of the fault southeast of Coyote Lake, but no surface faulting was seen in the epicentral area. A maximum 5-mm fault offset was recorded near San Felipe Lake, about 16 km south of the main shock. There was no prominent foreshock activity. The cumulative number of aftershocks (N) versus magnitude (M) could be described by the equation log N= 3.33 - 0.75 M, in the magnitude range between 1 and 3.5. The number and size of aftershocks appeared to be much less than that expected for a main shock of magnitude 5.7.

California