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R. C. McDowell

Publications and source records attributed to R. C. McDowell.

9 recordsLinked to original sources
USGS1991

E-4 Central Kentucky to the Carolina Trough

E-4 is one of eight Geodynamics transects that cross the Atlantic margin of North America between Georgia and Newfoundland. Five of the transects are in the United States and three are in Canada. Transect E-4, which is 110 km wide and more than 1,100 km long, extends from the stable North American craton just west of the Grenville front near Lexington, Kentucky southeastward across Cape Fear, North Carolina, on the Atlantic coast to oceanic crust east of the Blake Spur magnetic anomaly. Like all of the other U.S. Atlantic coast transects, it crosses Cambrian and Jurassic continental margins of North America as well as the Appalachian orogen. The display, based upon published information, portrays the geology, tectonic style and geophysical expression of this segment of the eastern North American continental margin and interprets its Phanerozoic history. The Decade of North American Geology 1983 geologic time scale (Palmer, 1983) is used throughout the display and text.

Book↗
USGS1983

Map showing distribution of small-scale deformation structures in a part of the upper coastal plain of South Carolina and adjacent Georgia

As a contribution to the assessment of neotectonics in the area of the Upper Coastal Plain of South Carolina, field traverses were made between Columbia, S.C., and Augusta, Ga., in 1975 and early 1976 in order to locate and describe small-scale deformation structures within exposed Coastal Plain rocks. The study covered most of the area between the Fall Line (northwest margin of the Coastal Plain) and the Orangeburg (Citronelle) escarpment (fig. 1). Fieldwork was done principally by vehicle along roads, but also included railroad cuts and excavation sites, such as quarries and landfills. Natural exposures are rare and provided no examples of deformation structures for this study. The geologic units exposed in the area are chiefly clastic sediments deposited in nearshore marine to continental environments. They include semi-consolidated sand, silt, clay, and rare thin impure limestone beds of Late Cretaceous to Eocene age (fig. 2). These sedimentary beds generally have a gentle regional dip to the southeast (Faye and Prowell, 1982, p. 6).

Georgia, South Carolina↗