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N.R. Shaffer

Publications and source records attributed to N.R. Shaffer.

3 recordsLinked to original sources

Inorganic ground-water chemistry at an experimental New Albany Shale (Devonian-Mississippian) in situ gasification site

Experimental in situ gasification of New Albany Shale (Devonian-Mississippian) has been conducted in Clark County. Analyses of ground water sampled from a production well and nine nearby monitoring wells 3 months after a brief in situ gasification period revealed changes in water chemistry associated with the gasification procedure. Dissolved iron, calcium and sulphate in ground water from the production well and wells as much as 2 m away were significantly higher than in ground water from wells over 9 m away. Dissolved components in the more distant wells are in the range of those in regional ground water. Thermal decomposition of pyrite during the gasification process generated the elevated levels of iron and sulphate in solution. High concentrations of calcium indicate buffering by dissolution of carbonate minerals. While iron quickly precipitates, calcium and sulphate remain in the ground water. Trends in the concentration of sulphate show that altered ground water migrated mostly in a south-westerly direction from the production well along natural joints in the New Albany Shale.

Indiana↗

Characterization of the oil shale of the New Albany Shale in Indiana

In the 1920's chemical and mineralogic characterization of the New Albany Shale (Mississippian-Devonian) in Indiana showed the dark shale to be rich in organic material and have commercial possibilities. Projects in the 1960's resulted in disparaging descriptions of exiguous fossil record, monotonous mineralogy, and intractable chemistry. Since 1978 expanded efforts have yielded much new information but new problems as well. Although organic carbon and total sulfur show positive correlation, two nearly exclusive populations exist. Material high in organic carbon is more depleted in C13 than material with less organic carbon. A bed usually at the top of the unit hosts anomalous accumulations of heavy metals and contains concentrations in similar ratios to those of sea water except for Mo and Pb and shows very negative ??S34. Heat content as Btu/lb, organic carbon (total less inorganic), and Fischer assay oil-yields generally correlate, but one is not an accurate predictor of the others.

Conference Paper↗