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Joel S. Watkins

Publications and source records attributed to Joel S. Watkins.

11 recordsLinked to original sources
USGS1979

Geology of the offshore Southeast Georgia Embayment, U.S. Atlantic continental margin, based on multichannel seismic reflection profiles

A geologic interpretation of the offshore Southeast Georgia Embayment is based on an 1,100-km multichannel seismic reflection survey conducted jointly by the University of Texas Marine Science Institute and the U.S. Geological Survey. The Southeast Georgia Embayment consists of a wedge of Cretaceous and Cenozoic sedimentary rocks that thins from 5 to 8 km beneath the Blake Plateau to about 1 km over the Cape Fear Arch. North of about 31°N lat. the sedimentary section onlaps a regional unconformity characterized by a strong, smooth reflector/high-velocity refractor (5.8 to 6.3 km/sec). Rocks below the unconformity may consist of Lower Jurassic volcanic(?) rocks, crystalline basement, or a high-velocity sedimentary layer. Acoustic basement south of 31°N lat. is an i regular unconformable surface that probably truncates a varied lithology consisting of Paleozoic (and Precambrian?) igneous, metamorphic, and sedimentary rocks or Triassic to Early Jurassic igneous and sedimentary rocks in fault basins, all of which crop out or have been drilled onshore. The sedimentary section is divided into three major seismic intervals. The intervals are separated by unconformities and can be mapped regionally. The oldest interval ranges in age from Early Cretaceous through middle Late Cretaceous, although it may contain Jurassic rocks where it thickens beneath the Blake Plateau. It probably consists of continental to nearshore clastic rocks where it onlaps basement and grades seaward to a restricted carbonate platform facies (dolomite-evaporite). The middle interval (Upper Cretaceous) is characterized by prograding clinoforms interpreted as open marine slope deposits. This interval represents a Late Cretaceous shift of the carbonate shelf margin from the Blake Escarpment shoreward to about its present location, probably due to a combination of co tinued subsidence, an overall Late Cretaceous rise in sea level, and strong currents across the Blake Plateau. The youngest (Cenozoic) interval represents a continued seaward progradation of the continental shelf and slope. Cenozoic sedimentation on the Blake Plateau was much abbreviated owing mainly to strong currents.

Southeast Georgia Embayment↗
USGS1966

Seismic refraction surveys in the vicinity of Eagle City, Clark County, Ohio

As part of a continuing program to define the thickness and extent of water-bearing sand and gravel deposits in southwestern Ohio, the U.S. Geological Survey, in cooperation with the Ohio Division of Water, in the summer of 1964 completed a seismic refraction survey in the vicinity of Eagle and Tremont Cities, Ohio (fig. 1). Similar surveys were completed in 1962 of the lower Great Miami River and Whitewater River Valleys (Watkins, 1963); in 1963 of the upper Great Miami River Valley (Watkins and Spieker, 1964) and of the Scioto River Valley (Watkins and Bailey, 1964). The area of the survey includes known or inferred portions of an interglacial drainage system which is deeply entrenched into bedrock. Ohio was covered by glaciers at least twice during the Pleistocene Epoch. As the last glacier retreated from Clark County, floods of meltwater deposited up to 300 ft of sand and gravel, now forming the lowlands of the Mad River Valley. The sand and gravel is highly permeable and saturated with large quantities of water of good quality. The underlying bedrock consists of limestone and dolomite, and limestone interbedded with shale. The limestone and dolomite sequence is the principal source of water along the edges of the buried valley where the sand and gravel thins. The city of Springfield has recently developed wells in the glacial deposits, and many industries in the area rely on wells in these deposits as their principal source of water. The purpose of the present survey is to define the thickness and extent of the important water-bearing sand and gravel deposits. Such information will make possible a more accurate evaluation of the area's water resources than has previously been possible.

Ohio↗
USGS1964

Basement depths from widely spaced aeromagnetic profiles in Kansas and Nebraska

Profiles of the basement surface in western Kansas and Nebraska were constructed by drawing smooth curves through the shallowest depths estimated from aeromagnetic anomalies along six widely spaced traverses. Ratios of inferred- depth -to- basement to true depth along the traverses ranges from 0.7 to 1.0. Clusters of shallow depth estimates commonly yield an average estimate within 15 percent of the true depth .

Kansas, Nebraska↗
USGS1964

Seismic refraction survey in the Great Miami River Valley and vicinity, Montgomery, Warren, and Butler Counties, Ohio

As part of a continuing program to define the thickness and extent of water-bearing sand and gravel deposits in southwestern Ohio, the U.S. Geological Survey, in cooperation with the Ohio Division of Water and The Miami Conservancy District, completed a seismic refraction survey of the Great Miami River valley and adjacent areas between Dayton and Hamilton, Ohio, in the fall of 1963. A similar survey of the adjoining lower Great Miami River and Whitewater River valleys was completed in 1962 (Watkins, 1963; Spieker and Watkins, unpublished data). The area of the survey includes known or inferred portions of an interglacial drainage system which is deeply entrenched into bedrock. Ohio was covered by glaciers at least three times during the Pleistocene epoch. As each glacier melted, rock fragments absorbed by the glacier were transported and deposited in these buried valleys by torrents of meltwater. The total thickness of glacial drift is over 300 feet in some places. Much of the glacial material is highly permeable and saturated with large quantities of water of good quality. The underlying bedrock is virtually impermeable and yields only meager quantities of water. The cities of Dayton, Middletown, Hamilton, and many industries in the Miami River valley rely on wells in the glacial deposits as their principal source of water. The purpose of the present survey is to define the thickness and extent of these important water-bearing formations. Such information will make possible a more accurate evaluation of the area's water resources than has previously have been possible.

Ohio↗
USGS1963

Refraction seismic studies in the Miami River, Whitewater River, and Mill Creek valleys, Hamilton and Butler Counties, Ohio

Between September 17 and November 9, 1962, the U.S. Geological Survey, in cooperation with Ohio Division of Water, Miami Conservancy District, and c,ty of Cincinnati, Ohio, co.,:ducted a refraction seismic study in Hamilton and Butler Counties, southwest Ohio. The area lies between Hamilton, Ohio, and the Ohio River and includes a preglacial valley now occupied by portions of the Miami River, Whitewater River, and Mill Creek. The valley is partially filled with glacial debris which yields large quantities of good-quality water. The object of the study was to determine the thickness of these glacial deposits and the shape of the preglacial valley.

Ohio↗