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G. S. Gohn

Publications and source records attributed to G. S. Gohn.

27 records · Page 2Linked to original sources
USGS1978

Regional implications of Triassic or Jurassic age for basalt and sedimentary red beds in the South Carolina coastal plain

Whole rock potassium-argon ages for samples of subsurface basalt recovered near Charleston, South Carolina, are interpreted to indicate a Triassic or Jurassic age for the basalt and underlying sedimentary red beds. This age is consistent with existing evidence indicating that an early Mesozoic basin is present in the subsurface of a large part of the coastal plain of South Carolina, Georgia, Florida, and Alabama.

South Carolina↗
USGS1978

Uranium and phosphate resources in the Cooper Formation of the Charleston region, South Carolina

Phosphate deposits formerly exploited in the Charleston district were formed by weathering and reworking of the Cooper Formation (Eocene and Oliogcene). Previous workers have shown that unusual concentrations of uranium occur in phosphate-rich nodular material formed during subareal weathering. We found that the old mining district is on an erosional high of the Cooper Formation and in a topographic depression, but that the process of weathering enrichment of the Cooper Formation extends beyond the mining district. Fresh sediments from the Cooper Formation average 14.5 ppm uranium and 1.0 percent P 2 0 5 for Oliogcene samples and 5.6 ppm U and 0.15 percent P 2 0 5 for Eocene samples. Zones of secondary enrichment over undifferentiated Cooper Formation average 2 m thick and have average values of 60 ppm U and 5.4 percent P 2 0 5 . No deposits clearly of economic importance were found, although detailed studies may reveal such deposits.

South Carolina↗
USGS1976

Ground radioactivity measurements in South Carolina and Georgia with radioelement analyses of surficial sediments

Recently published aeroradioactivity maps of parts of the South Carolina and Georgia Coastal Plain, have defined numerous areas of anowlously high total gamma ray intensity (Coastal Plain Regional Commission and U.S. Geological Survey, 1975, Aeroradioactivity maps of parts of Georgia, South Carolina, and North Carolina: U.S. Geol. Survey Open-file Report 75-400, 1:250,000, 15 pls.). During the present study, areas in South Carolina and Georgia having high total gamma aeroradioactivity were sampled in one of two ways. Individual samples labeled "Georgia grab samples", "Columbia grab samples", and "Frogmore samples" were each collected as close as possible to the center of aeroradioactivity highs. Groups of samples labeled St. Matthews, Tillman, Gray's Hill, Route 99, Route 196, and Route 276 were collected by sampling along existing roads that transect aeroradioactivity highs. At each sample location five to ten pound samples were taken from the top two-to-three inches of sediment. The samples were dried, split, and analysed for uranium, thorium, and potassium by gamma-ray spectrometry. In the accompanying table uranium contents are presented as RAEU (radium equivalent uranium) in parts per million (ppm). Thorium is presented in parts per million (ppm) and potassium in percentage (pct). Ground counts of total gamma intensity were taken in the field with a McPhar IV four-channel scintillometer. Gamma ray intensity is presented as counts per minute (cpm) averaged over ten second intervals. More samples and ground radioactivity measurements were taken than are presented in the following table. Only those samples that were analysed for radioelements are listed. Collection of the "Georgia grab samples" was a joint effort of the Georgia Geologic and Water Division and the U.S. Geological Survey. Brenda B. Higgins, John Hack, Isidore Zeitz and Robert Schmidt provided useful discussions concerning the selection of areas to be sampled.

Georgia, South Carolina↗