Results of a geochemical survey, Aban Al Ahmar Quadrangle, Sheet 25F, Kingdom of Saudi Arabia

W. Roger Miller; M. A. Arnold

doi:10.3133/ofr88605

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Results of a geochemical survey, Aban Al Ahmar Quadrangle, Sheet 25F, Kingdom of Saudi Arabia

W. Roger Miller·M. A. Arnold

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Abstract

The interpretation of geochemical data from a regional survey of the Aban al Ahmar quadrangle resulted in the selection of areas for follow-up studies. The results of detailed geochemical studies of these areas, combined with field observation, resulted in the selection of areas of moderate to high mineral resource potential. The most important areas are (1) the Jibal Minyah area, Aban al Asmar area, Jibal Suwaj area, and Nubayah area where tin and tungsten mineralization are associated with Abanat-suite rocks or possible buried Abanat-suite plutons; (2) several areas containing rocks of the Murdama group in the northern part of the quadrangle, the Buqaya al Luaah area, and the Jabal Akkash area where precious- and base-metal mineralization are generally associated with small Idah-suite plutons; and (3) the southern periphery of Jibal Qitan associated with skarn mineralization. The Aban al Ahmar quadrangle (sheet 25F) lies in the northeastern part of the Proterozoic Arabian Shield. Plots showing the distribution of single elements and factor scores of the regional geochemical data for wadi concentrates were used to select favorable areas for follow-up work. Detailed follow-up studies consisted of the collection of samples of rocks, wadi concentrates, and wadi sediments. The most useful pathfinder elements for precious- and base-metal mineralization are Cu and Pb, and for tin and tungsten mineralization they are Sn, La, Nb, Y, and Be. R-mode factor analysis of the regional geochemical data resulted in two factors that reflect mineralization: precious- and base-metal mineralization; and Abanat-suite lithology and, therefore, tin and tungsten mineralization. A major problem in the interpretation of the regional geochemical data resulted from incomplete removal of magnetite from the samples prior to analysis. The presence of magnetite can cause anomalous values of Ni, Fe, V, Cu, and Co in samples because of it's ability to incorporate these elements into its structure during magmatic crystallization.

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Source-reported bounding extent: 25° to 26° latitude; 42° to 44° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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W. Roger Miller, M. A. Arnold. 1988. Results of a geochemical survey, Aban Al Ahmar Quadrangle, Sheet 25F, Kingdom of Saudi Arabia. https://doi.org/10.3133/ofr88605

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