14 Undergraduate Research (Posters)

Monday, 13 May 2002
1:30 PM - 5:30 PM

GEOLOGY OF THE WHITE PINE MTS. ALONG HIGHWAY 50, EASTERN NEVADA 2001 GEOLOGY FIELD CAMP

Paper number: 14-18
Program: THEME SESSIONS
Time: 1:30 PM – 5:30 PM

Authors

Abstract

A geologic map was constructed of a thirty-two square mile area located in the White Pine Range, Eastern Nevada. This mapping area extends directly south of the seventy-two square miles mapped by HSU 1999 geology field camp. Paleozoic formations mapped include Devonian Pilot Shale, Mississippian Joanna Limestone, Chainman/Diamond Peak Formation, Pennsylvanian Ely Limestone, Permian Rib Hill Sandstone, and Arcturus Formation. The Pilot Shale consists of finely bedded carbonate mudstones. Ely and Arcturus Limestones are typically massive and consist of grainstone and wackestone. The Ely Limestone is characterized by brachiopods and chert stringers, while the Arcturus Limestone contains fussilinids. The Joanna Limestone is a massive grainstone and wackestone that contains bryozoans, crinoids, and spongoporia. Antlerland derived clastic Chainman/Diamond Peak Formation is composed of sandstone, carbonate mudstone, and small lenses of pebble conglomerate, with the conglomerates forming resistant layers one to three m thick. Rib Hill Formation consists of grainstone and wackestone ledge forming member and a slope forming sandstone member. Tertiary units include Sheep Pass Formation, Red Sediments, and Volcanics. Generally Sheep Pass Formation is underneath other Tertiary units, but interfingers laterally with Red Sediments and Volcanics farther up section. Sheep Pass Formation consists of white gray tuffaceous lacustrine limestone, succeeded by Red Sediments characterized by siliciclastic fanglomerates and unconsolidated carbonates. Both Red Sediments and Sheep Pass rest unconformably upon Paleozoic rocks. Younger volcanic rocks include welded, unwelded tuff and ignimbrite sequences. Four generations of Quaternary fan deposits are present.

Unconformities present suggest Paleozoic formations were folded prior to deposition of Tertiary sediments. Folds trend north-south with wavelengths of one-half to several km. The multiple breached north-south trending folds have east-west vergent axial surfaces. North-northeast normal faults crosscut Tertiary units and are then crosscut by north-south trending normal Basin and Range faults, suggesting two periods of extension.

Nevada, Antlerland, normal faulting, volcanics