Regional geochemical study of the felsic plutonic rocks in the Nuqrah Quadrangle, sheet 25E, Kingdom of Saudi Arabia

W. E. Hall; David Dellinger; G.I. Selner

doi:10.3133/ofr8525

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Regional geochemical study of the felsic plutonic rocks in the Nuqrah Quadrangle, sheet 25E, Kingdom of Saudi Arabia

W. E. Hall·David Dellinger·G.I. Selner

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Abstract

A regional geochemical investigation of the felsic plutonic rocks of the Nuqrah quadrangle, sheet 25 E, Kingdom of Saudi Arabia, in which pan concentrates of 384 wadi samples, and 145 rock samples, were collected, defined two separate and distinct anomalous areas. One area contains Jabal Tuwalah and Jabal Awja, and the other is at the north end of Jabal Safad. Both pan concentrates and the rock samples in the Jabal Tuwalah and Jabal Awja areas contain high concentrations of Be, F, La, Mo, Nb, Pb, Th, U, Sn, Y, and Zr, and the plutons underlying those areas are characterized by high total-count radioactivity. These elements are sited in highly evolved alkalic granites and have not been concentrated into a potentially metalliferous deposit related to a hydrothermal ore system. They may be a potential metal source of the future. Pan-concentration samples collected from wadis draining the north end of Jabal Safad contain anomalous Sn, Mo, Pb, and La. Four samples contain 250 to 1,000 ppm of tin. The tin anomaly is associated with a small aplitic pluton intrusive into the Jabal Safad alkalic granite complex. A brief reconnaissance of the area did not reveal any greisen or cassiterite mineralization. However, further exploration work in the area is recommended.

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Source-reported bounding extent: 25° to 26° latitude; 40° to 42° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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W. E. Hall, David Dellinger, G.I. Selner. 1985. Regional geochemical study of the felsic plutonic rocks in the Nuqrah Quadrangle, sheet 25E, Kingdom of Saudi Arabia. https://doi.org/10.3133/ofr8525

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