Preliminary sulfur isotope investigations of mineral deposits in the Precambrian shield, Kingdom of Saudi Arabia

Ralph Jackson Roberts; Robert O. Rye; Mustafa M. Mawad

doi:10.3133/ofr78776

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Preliminary sulfur isotope investigations of mineral deposits in the Precambrian shield, Kingdom of Saudi Arabia

Ralph Jackson Roberts·Robert O. Rye·Mustafa M. Mawad

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Abstract

Massive sulfide deposits and sulfide-bearing veins in Saudi Arabia show a wide range in δ 34 S values from very negative to strongly positive and cover almost the entire range observed for ore deposits in nature. Massive sulfide deposits that have very negative values (Wadi Wassat and Wadi Qatan) formed as syngenetic sedimentary deposits in stagnant, euxinic basins. Deposits that have large positive values (Khnaiguiyah and Al Amar) were formed by sea water hydrothermal systems. Gold- and silver-bearing veins whose δ 34 S values fall near 0 permil (Mand adh Dhahab and Samrah) are believed to have derived both sulfur and metals from magmatic sources. Massive sulfide deposits whose δ 34 S values range from slightly negative to slightly positive (Kutam, Al Masane, Wadi Bidah, and Jabal Sayid) are thought to have been formed largely from sea water hydrothermal systems, though deep-seated contributions of sulfur cannot be ruled out. Some deposits in this group (Nuqrah and AT Ridayniyah) appear to have derived their sulfur from volcanic exhalative sources.

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Source-reported bounding extent: 17.221462718170713° to 28.99826069483788° latitude; 34.728029294132284° to 55.48802991062243° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Ralph Jackson Roberts, Robert O. Rye, Mustafa M. Mawad. 1978. Preliminary sulfur isotope investigations of mineral deposits in the Precambrian shield, Kingdom of Saudi Arabia. https://doi.org/10.3133/ofr78776

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