By: P. T. McCarthy and D. M. Miller
Much of Terrace Mountain, an isolated small mountain on the north edge of the Great Salt Lake Desert, is within the Terrace Mountain East quadrangle. Permian and Triassic rocks that were folded into a large north-trending syncline underlie the mountain. Faults cutting these rocks are typically marked by altered breccia, which is prospected at one place. Miocene strata overlying these older rocks dip westward, either as a result of emplacement as a low-angle, fault-bounded sheer across the older rocks or by deposition against and subsequent tilting with the older rocks. Relations in the adjacent Terrace Mountain West quadrangle point to the low-angle fault interpretation. Quaternary alluvial, lacustrine, and eolian sediments blanket much of the quadrangle. In particular, lacustrine deposits display the many shorelines of late Pleistocene Lake Bonneville.
Pages: 14 p.
Plates: 2 pl.
Location: Box Elder County
Media Type: Paper Map