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D. E. White

Publications and source records attributed to D. E. White.

33 records · Page 2Linked to original sources
USGS1973

Silica-carbonate alteration of serpentine: Wall rock alteration in mercury deposits of the California Coast Ranges

Chemical, isotopic, and thermodynamic properties have been measured of CO 2 -rich ground waters in the central California Coast Ranges. The acidic CO 2 -rich waters react with serpentine to form silica-carbonate rock, the host rock of many mercury deposits in the Coast Range of California. In part the waters are of a metamorphic origin and in part the waters are locally derived meteoric waters. The CO 2 is entirely derived from metamorphic reactions at depth. Depending on the relative importance of several reactions, the relative abundances of silica and carbonate minerals vary in the silica-carbonate rock. If the CO 2 -rich fluids react directly with peridotite or dunite, massive magnesite deposits may form. © 1973 Society of Economic Geologists, Inc.

California↗
USGS1973

Production of superheated steam from vapor-dominated geothermal reservoirs

Vapor-dominated geothermal systems such as Larderello, Italy, The Geysers, California, and Matsukawa, Japan yield dry or superheated steam when exploited. Models for these systems are examined along with production data and the thermodynamic properties of water, steam and rock. It is concluded that these systems initially consist of a water and steam filled reservoir, a water-saturated cap rock, and a water or brine-saturated deep reservoir below a water table. Most liquid water in all parts of the system is relatively immobilized in small pores and crevices; steam dominates the large fractures and voids of the reservoir and is the continuous, pressure-controlling phase. With production, the pressure is lowered and the liquid water boils, causing massive transfer of heat from the rock and its eventual drying. Passage of steam through already dried rock produces superheating. After an initial vaporization of liquid water in the reservoir, the decrease in pressure produces increased boiling below the deep water table. With heavy exploitation, boiling extends deeper into hotter rock and the temperature of the steam increases. This model explains most features of the published production behavior of these systems and can be used to guide exploitation policies.

Geothermics↗
USGS1971

Classification of public lands valuable for geothermal steam and associated geothermal resources

The Organic Act of 1879 (43 U.S.C. 31) that established the U.S. Geological Survey provided, among other things, for the classification of the public lands and for the examination of the geological structure, mineral sources, and products of the national domain. In order to provide uniform executive action in classifying public lands, standards for determining which lands are valuable for mineral resources, for example, leasable mineral lands, or for other products are prepared by the U.S. Geological Survey. This report presents the classification standards for determining which Federal lands are classifiable as geothermal steam and associated geothermal resources lands under the Geothermal Steam Act of 1970 (84 Star. 1566). The concept of a geothermal resources province is established for classification of lands for the purpose of retention in Federal ownership of rights to geothermal resources upon disposal of Federal lands. A geothermal resources province is defined as an area in which higher than normal temperatures are likely to occur with depth and in which there is a reasonable possibility of finding reservoir rocks that will yield steam or heated fluids to wells. The determination of a 'known geothermal resources area' is made after careful evaluation of the available geologic, geochemical, and geophysical data and any evidence derived from nearby discoveries, competitive interests, and other indicia. The initial classification required by the Geothermal Steam Act of 1970 is presented.

Circular↗
USGS1966

Preliminary investigation of the source of lead and strontium in deep geothermal brines underlying the Salton Sea geothermal area

A radiogenic tracer study has been made of lead and strontium in deep geothermal brines , salt from brine , and the upper Quaternary rhyolite domes near the Salton Sea in the Imperial Valley, California. The data on the brines and rhyolite glasses are compared to those from Quaternary Colorado River and Tertiary sediments of the area . The brines sampled contain '-'100 ppm Pb, sufficient for consideration as a possible ore-forming fluid. The isotopic data indicate that 80-100 percent of the strontium and 50-100 percent of the lead in these brines were acquired from the associated sediments. The isotopic compositions of lead and strontium in the Quaternary rhyolite glasses are distinctly different from those of the sediments and brines . The strontium data suggest that the rhyolite glasses were derived from basaltic or gabbroic material but may have attained as much as 40 percent of their strontium from upper crustal rocks such as the sediments analyzed.

California↗
USGS1963

Geothermal brine well: Mile-deep drill hole may tap ore-bearing magmatic water and rocks undergoing metamorphism

A deep geothermal well in California has tapped a very saline brine extraordinarily high in heavy metals and other rare elements; copper and silver are precipitated during brine production. Preliminary evidence suggests that the brine may be pure magmatic water and an active ore-forming solution. Metamorphism of relatively young rocks may also be occurring within accessible depths.

California↗
USGS1963

Volcanic emanations

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Professional Paper↗