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Adel A. R. Zohdy

Publications and source records attributed to Adel A. R. Zohdy.

At least 37 records · Page 2Linked to original sources
USGS1976

Schlumberger soundings near Fallon, Nevada

In 1976, the U.S. Geological Survey, in cooperation with the Nevada Division of Water Resources, made thirty one Schlumberger resistivity soundings near the city of Fallon, Nevada. The survey was made to estimate and delineate the volume of fill containing fresh ground water and to map the lateral extent and thickness of basalt layers which act as the principle aquifer in the area.

Nevada↗
USGS1976

Geology and geophysics of the southern Raft River Valley geothermal area, Idaho, USA

The Raft River valley, near the boundary of the Snake River plain with the Basin and Range province, is a north-trending late Cenozoic downwarp bounded by faults on the west, south, and east. Pleistocene alluvium and Miocene-Pliocene tuffaceous sediments, conglomerate, and felsic volcanic rocks aggregate 2 km in thickness. Large gravity, magnetic, and total field resistivity highs probably indicate a buried igneous mass that is too old to serve as a heat source. Differing seismic velocities relate to known or inferred structures and to a suspected shallow zone of warm water. Resistivity anomalies reflect differences of both composition and degree of alteration of Cenozoic rocks. Resistivity soundings show a 2 to 5 ohm·m unit with a thickness of 1 km beneath a large part of the valley, and the unit may indicate partly hot water and partly clayey sediments. Observed self-potential anomalies are believed to indicate zones where warm water rises toward the surface. Boiling wells at Bridge, Idaho are near the intersection of north-northeast normal faults which have moved as recently as the late (?) Pleistocene, and an east-northeast structure, probably a right-lateral fault. Deep circulation of ground water in this region of relatively high heat flow and upwelling along faults is the probable cause of the thermal anomaly.

Idaho↗
USGS1974

Application of surface geophysics to ground-water investigations

This manual reviews the standard methods of surface geophysics applicable to ground-water investigations. It covers electrical methods, seismic and gravity methods, and magnetic methods. The general physical principles underlying each method and its capabilities and limitations are described. Possibilities for non-uniqueness of interpretation of geophysical results are noted. Examples of actual use of the methods are given to illustrate applications and interpretation in selected geohydrologic environments. The objective of the manual is to provide the hydrogeologist with a sufficient understanding of the capabilities, imitations, and relative cost of geophysical methods to make sound decisions as to when to use of these methods is desirable. The manual also provides enough information for the hydrogeologist to work with a geophysicist in designing geophysical surveys that differentiate significant hydrogeologic changes.

Techniques of Water-Resources Investigations↗
USGS1971

Resistivity sections, upper Arkansas River basin, Colorado

A reconnaissance investigation of ground-water resources in the upper Arkansas River basin from Pueblo to Leadville is being made by the U.S. Geological Survey in cooperation with the Southeastern Colorado Water Conservancy District, and the Colorado Division of Water Resources, Colorado State Engineer. As part of the investigation, surface geophysical electrical resistivity surveys were made during the summer and fall of 1970 near Buena Vista and Westcliffe, Colo. (p1.1). The resistivity surveys were made to verify a previous gravity survey and to help locate areas where ground-water supplies might be developed. This report presents the results of the surveys in the form of two resistivity sections.

Colorado↗