A Contribution to the Geochemical Atlas of the Kingdom of Saudi Arabia: Geochemical Survey of the Al Hamra Quadrangle, 23C
Ibrahim O. Abdalla, Abdulrahman A. Sabbahi, Yaser S. Al-Ghanmi, Mohammed O. Al-Nashri,
Abdullah Al-Eisa, and Mazen B. Balkheyour
The geochemical mapping of the Al Hamra quadrangle is based on the collection of 101 stream-sediment samples (including 5 percent duplicates) from Proterozoic supracrustal/plutonic basement terrain. ICP and AAS analyses of the -2 mm / +0.177 mm fraction of these samples have been used to identify districts with indications of mineralization or ore-forming processes. Spatial variations in the analytical data are presented as geochemical maps to identify single-element districts, which have been synthesized to define multi-element anomaly targets for future follow-up. Based on their consistent elemental associations and their similarities with known ore-deposit types, the identified multi-element anomalies include two rated as Priority 1, two as Priority 2, and six as Priority 3. The element associations of the two Priority 1 anomalies are suggestive of gold and /or sulfide mineralization, hosted by supracrustal/granitic terrain. Of the Priority 2 anomalies, one is interpreted as representing Fe-Ti mineralization and the other is suggestive of REE mineralization, also in supracrustal/granitic terrain. The Priority 3 anomalies show a variety of elemental associations, including gold, sulfides, REE, Fe-Ti, and Ba. XRD analyses of selected samples have confirmed the presence of Au-bearing minerals, and other minerals suggestive of the presence of pegmatite, carbonatite and kimberlite. Although the program was mineral-exploration oriented, the resultant database is suitable for environmental monitoring, geological mapping, and land-use planning.
Abdalla, I.O., Sabbahi, A.A., Al-Ghanmi, Y.S., Al-Nashri, M.O., Al-Eisa, A.M.I., and Balkheyour, M.B., 2013, A contribution to the Geochemica Atlas of the Kingdom of Saudi Arabia: Geochemical survey of the Al Hamra Quadrangle, 23 C: Saudi Geological Survey Technical Report SGS-TR-2013-3, 97 P., 86, figs., 3 tables, 4 apps.