A fault-controlled, hydrothermal system deposited gold, stibnite, and quartz in metasediments, intrusive basalt, and diorite in an area approximately 3 by 5 km in the Meshaheed area of the northeastern Arabian Shield. Veins in metasediments appear to be lenticular and average less than 1 m thick. A related, quartz-pyrite stockwork in fractured, hydrothermally altered basalt is approximately 1 km long and at least 100 m wide. Poorly defined veins and veinlets bear gold, stibnite, and quartz, A few areas of ancient goldmining activity are in metasediments at the perimeter of a large diorite pluton. The arrangement of the pits also indicates that unexposed veinlet systems may be as much as 40 m wide. Small areas of diorite have also been hydrothermally altered where gold-stibnite-quartz veins were emplaced.
A molybdenite-quartz stockwork and other quartz stockworks bearing traces of molybdenum, bismuth, and silver are in small diorite plutons. Large areas of moderately hydrothermally altered metasediments bearing trace molybdenum are also present. These mineralized zones are not cogenetic with the gold-stibnite-quartz deposits.
A separate stream-sediment sampling program has shown the area southeast of Meshaheed to be anomalous in lead, copper, boron, tin, iron, and molybdenum, and a preliminary geophysical survey found resistivity anomalies coincident with the altered, intrusive basalt.
