The Wadi as Sirhan quadrangle lies in the northwestern pan of Saudi Arabia on the border with Jordan. It is located in the west-central part of the Sirhan-Turayf basin and is underlain by Silurian to Miocene-Pliocene sedimentary rocks that are partly covered by volcanic flows. The map area also contains large areas of surficial sand and gravel.
The study area is mainly a structural depression formed by the Wadi as Sirhan graben complex, and it is flanked by highlands of moderate altitude. The Wadi as Sirhan graben is believed to have been formed by tensional forces associated with rifting in the Red Sea.
The map area contains the Thaniyat, Ghinah, and Arqah phosphorite members, and the phosphate-bearing Sib member. Hypothetical estimates of mineral resource potential of the phosphate rock in the quadrangle are high, but most prospects are either covered with too much overburden or are too thin and of too low a grade to be considered for economic exploitation at this time.
Several deep drill holes in the Wadi as Sirhan depression have penetrated thick sequences of marine rocks that are potential sources of oil and gas. Geological and geophysical conditions are favorable for the accumulation of hydrocarbons, and additional exploration is recommended.
