The rocks along Ingle Creek are primarily upper Paleozoic greenschist-facies metasedimentary and metavolcanic rocks that have been intruded by granitic rocks that are either related to the Taylor Mountain batholith of Triassic age to the south or the Chicken pluton of Jurassic age that crops out at the head of the valley (Werdon and others, 2001). These units have been cut by numerous high-angle faults. In the lower part of Ingle Creek, Tertiary gabbro is overlain by tuffaceous material and sparse shale. Quaternary colluvium and alluvium are present in the lower valley.Free gold occurs in quartz and calcite veins here (Smith, 1968). The occurrence is about 3 miles west of the Purdy lode gold mine (EA121), which is a similar deposit of gold in quartz and calcite veins.