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USGS · ofr7360

Geology and evaluation of tungsten anomalies, Buhairan-Abu Khurg area, southeastern part of the Uyaijah ring structure, Kingdom of Saudi Arabia

Abstract

Previous geochemical exploration has indicated areas in the Precambrian Al Uyaijah ring structure for further investigation. This report encompasses the results of geologic and geochemical investigations made in a 40 square kilometer area located on the southeast perimeter of the ring structure, an area where previous geochemical exploration revealed anomalous tungsten and molybdenum values. Igneous rocks exposed in the area include batholithic plutonic rocks, intrusive rocks of the ring dike, hypabyssal dike rocks, and late epithermal quartz veins; remnants of metamorphosed, prebatholithic rocks are also exposed. About two-thirds of the area is covered with a veneer of surficial debris. Structural patterns of the area are dominated by the ring structure. The principal mineralization consists of powellite and scheelite in high-temperature, quartz-rich veinlets and pods and in contact metamorphic rocks. Although the areas of metallization account for the previously discovered sediment geochemical anomalies, mineralization is sparse, and no currently valuable mineral deposits are known or thought to be present in the area.

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BibTeXRIS

F. C. W. Dodge. 1973. Geology and evaluation of tungsten anomalies, Buhairan-Abu Khurg area, southeastern part of the Uyaijah ring structure, Kingdom of Saudi Arabia. https://doi.org/10.3133/ofr7360

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