Search USGS⌕ Search

Geology topics

J. Fred Smith

Publications and source records attributed to J. Fred Smith.

11 recordsLinked to original sources
USGS1974

Folds and overthrusts of late Jurassic or early Cretaceous age in northern Nevada

The partly isoclinal, partly overturned Adobe syncline extends for at least 75 mi northeastward across the northern Cortez Mountains, the northern Pinon Range, and along the entire length of the Adobe Range. The folded rocks range in age from Ordovician through Jurassic and may include some rocks of Cretaceous age. This syncline is flanked by anticlines in the central and southern parts of the Pinon Range and in the southern Independence Mountains. In places the Adobe syncline is discordantly overlain by nearly flat-lying thrust plates composed of Ordovician, Devonian, Mississippian, and Permian rocks. The geometric relations indicate that these thrust plates moved at least 6 mi, but postfold thrust movement was not great, because the Mississippian and Permian rocks of the thrust plates closely resemble correlative autochthonous rocks nearby. The Ordovician and Devonian rocks have been thrust to their present position in at least two stages; the earlier movement or movements took place long before folding of the Adobe syncline and the later movement immediately afterward. The folding and last stage of thrusting were in Late Jurassic or Early Cretaceous time.

Nevada↗
USGS1963

Geology of the Capitol Reef area, Wayne and Garfield Counties, Utah

The Capitol Reef area includes about 900 square miles in western Wayne and north-central Garfield Counties, Utah. It is along the border between the High Plateaus of Utah and the Canyon Lands sections of the Colorado' Plateaus province. Capitol Reef National Monument is in the eastern part of the mapped area.

Utah↗