By: C. L. Weaver and L. F. Hintze
The Blue Mountain quadrangle lies in the southern Wah Wah Mountains, just west of the Escalante Desert, 25 miles southwest of Milford, Utah. The oldest exposed rocks are Middle Cambrian limestone, dolomite, and shale units that are thrust over Lower Jurassic and Triassic strata of the Temple Cap, Chinle, and Moenkopi Fonnations and Navajo Sandstone. The overthrust is particularly well exposed on Blue Mountain, a north-south, basin-and-range horst. On Blue Mountain, and at two other localities in the quadrangle, the overthrust is folded into broad anticlines which may have formed above inferred laccolithic intrusions. Oligocene and Miocene volcanic rocks, more than 5,000 feet thick, rest with moderate angular unconformity on the Paleozoic and Mesozoic strata. The oldest units in the volcanic sequence are an informally named tuff, a volcanic debris flow, and a conglomerate.
Pages: 17 p.
Plates: 2 pl.
Location: Beaver County
Media Type: Paper Map