Name applied to the highest member (of four) of Benton shale of Colorado group. Named for Torchlight dome, Bighorn Co., WY, Bighorn basin, where member is well exposed on both sides of deep gulch that cuts center of dome. No type locality designated. Has hard resistant layers. Makes prominent escarpment. No fossils found. Consists of gray to white saccharoidal sandstone, cross-bedded, capped by poorly cemented layer of black and gray pebbles. Varies from crumbly to well indurated. Has been designated the "B" sandstone. Overlies the "Upper Benton shale member." Underlies lower conglomerate of Basin shale (first used) of Colorado group. Torchlight Basin contact is an erosion surface. Geologic map; member not separately mapped. Stratigraphic table. Of Late Cretaceous age.

Source: GNU records (USGS DDS-6; Denver GNULEX).