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J. S. Williams

Publications and source records attributed to J. S. Williams.

10 recordsLinked to original sources
USGS1967

Devonian of the Southwestern United States

The structural framework that controlled Devonian deposition consisted of, from west to east: (1) a eugeosynclinal area in northern California and western Nevada; (2) a miogeosynclinal area in southeastern California, eastern Nevada, and western Utah; and (3) a cratonic area in Arizona, eastern Utah, Colorado, New Mexico, and western Texas, east of a northeast-trending hinge line (Wasatch line). The eugeosyncline contains a fragmentary record of Middle Devonian rocks at least 4,000 feet thick characterized by thin-bedded chert, siliceous mudstone, and some limestone and volcanic rocks. The original thickness, however, probably exceeded 6,000 feet and probably included Lower and Upper Devonian rocks. The miogeosyncline contains Lower, Middle, and Upper Devonian rocks as much as 6,000 feet thick characterized by thick units of dolomite and limestone and some local interbeds of sandstone. A transitional zone perhaps 50 miles wide separates the eugeosynclinal and miogeosynclinal facies. The craton contains mostly Upper Devonian rocks, generally less than 1,000 feet thick, characterized by dolomite and limestone and local interbeds of sandstone and mudstone. Widespread crustal movements occurred during Late Devonian time. The Antler orogeny in Nevada initiated a culm facies in the geosyncline. Eugeosynclinal and transitional rocks including those of Devonian age were uplifted to form the Antler orogenic belt, and then were thrust eastward over autochthonous miogeosynclinal rocks in latest Devonian or earliest Mississippian time. Folding and faulting, and subsequent erosion on local uplifts, produced clastic deposits of Late Devonian age in Utah and southwestern Colorado. Devonian rocks in many parts of the geosynclinal area have been moved since Devonian time by large-scale, generally eastward thrusting, oroflexural bending and strike-slip faulting. Four major subdivisions of the Devonian System and related rocks are treated separately: 1) Lower Devonian (Gedinnian, Siegenian, Emsian) and related Upper Silurian (Ludlovian) rocks. 2) Middle Devonian (Eifelian and Givetian) rocks. 3) Lower Upper Devonian (Frasnian, to I ) rocks. 4) Upper Upper Devonian (Famennian, to II-VI ) and related lowermost Mississippian (Tournaisian, cu I ) rocks.

Conference Paper↗
USGS1962

Lake Bonneville: Geology of southern Cache Valley, Utah

This report, covering about 450 square miles in southern Cache Vally, Utah, is one of a series dealing with the geology of Pleistocene Lake Bonneville. The report summarizes in tabular form the Paleozoic formations that are exposed in the mountains adjacent to Cache Valley and describes briefly the Tertiary formations—the Wasatch and Salt Lake formations— which are exposed in the valley. Most of the report deals with the Quaternary deposits. Fan gravel and landslides of pre-Lake Bonneville Quaternary age are exposed in a few places at the edges of the basin, and well logs indicate a deep fill of this age in the subsurface of the basin interior. The sediments of Lake Bonneville comprise the Lake Bonneville group. The oldest of the unconsolidated deposits are the Alpine and Bonneville formations, which were mostly mapped together in southern Cache Valley. These formations are composed mostly of silt, but they include some gravel in embankments and small deltas. Their thickness ranges from about 50 to 100 feet. Overlying the Alpine and Bonneville formations is the Provo formation 50 to 75 feet thick. In Cache Valley, as elsewhere in the Lake Bonneville basin, the Provo includes extensive gravel deposits in bars, spits, and deltas. It is the surface formation in much of Cache Valley. Deposits younger than the Provo, mostly of Recent age, include alluvial flans, flood-plain alluvium, natural levee deposits along the Bear River, slope wash, eolian sand, and cones of spring tufa. Several faults, active in Tertiary time, are mapped. Well logs indicate that the pre-Lake Bonneville deposits of Quaternary age are surprisingly thin in Cache Valley, suggesting that the valley had exterior drainage during most of Pleistocene time. The logs show two main aquifers of gravel and sand— the upper one between the Provo formation and the Alpine and Bonneville formations and the other directly beneath the Alpine and Bonneville deposits. These aquifers probably are alluvium deposited during interlake intervals. The shore embankments and deltas of the Lake Bonneville group are abundant sources of gravel and sand for construction. Much of the gravel is suitable for concrete aggregate.

Utah↗