Reconnaissance geology of the Jabal Khatam Quadrangle, sheet 26/39 D, Kingdom of Saudi Arabia

The Jabal Khatam quadrangle encompasses an area of about 2,725 km² on the edge of the Precambrian shield in northwestern Saudi Arabia, between lat 26°00' and 26°30' N. and long 39°30' and 40°00' E. The southern one-third and northeastern corner of the area are covered by Tertiary and Quaternary basalt flows of Harrat Khaybar and Harrat Ithnayn. In one small area on its northern edge, Harrat Khaybar is composed of Tertiary rhyolitic tuff and trachyte. Most of the northern one-third and eastern part of the quadrangle are covered by Paleozoic Siq Sandstone. The remainder of the quadrangle is composed of trachyandesite flows, agglomerate, graywacke, and sparse marble of the Hulayfah group and intrusive rocks that range in composition from alkali-feldspar granite to diabase. No deposits with economic potential were found. However, the geothermal potential of the quadrangle warrants further investigation.