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Reconnaissance geology of the Wadi Dhahaban Quadrangle, sheet 18/41 D, Kingdom of Saudi Arabia

Donald G. Hadley
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Abstract

The Wadi Dhahaban quadrangle (sheet 18/41 D) lies between lat 18?00? and 18?30' N. and long 41?30' and 42?00' E. and encompasses an area of 2,937 km2 located along the Red Sea coast and includes part of the escarpment-mountains province. The geologic formations exposed in the quadrangle are comprised of Precambrian layered and intrusive rocks, Tertiary gabbro dikes, Quaternary basaltic lavas and pyroclastic rocks, and Quaternary surficial deposits. No economic mineral deposits have been found. The Precambrian rocks include layered sedimentary and volcanic rocks that have been assigned to the Baish, Bahah, and Ablah groups. They have been folded, metamorphosed, and invaded by three separate intrusions. The Precambrian rocks are cut by Miocene gabbro dikes that were intruded during the initial stages of the opening of the Red Sea rift. The Quaternary rocks include basalt, and coastal, pediment, and alluvial deposits of various kinds. The area is of special interest because of its unique display of the Tertiary and Quaternary basaltic volcanism that was associated with the opening of the Red Sea rift and that has continued in other parts of the Kingdom until historic times.

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BibTeXRIS

Donald G. Hadley. 1982. Reconnaissance geology of the Wadi Dhahaban Quadrangle, sheet 18/41 D, Kingdom of Saudi Arabia. https://doi.org/10.3133/ofr82288

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