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J.B. Roen

Publications and source records attributed to J.B. Roen.

10 recordsLinked to original sources
USGS1988

Evidence of land plant affinity for the Devonian fossil Protosalvinia (Foerstia)

The Devonian plant fossil Protosalvinia (Foerstia) has been examined by solid-state 13 C nuclear magnetic resonance spectroscopy (NMR) and pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS). Results of these studies reveal that the chemical structure of Protosalvinia is remarkably similar to that of coalified wood. A well-defined phenolic carbon peak in the NMR spectra and the appearance of phenol and alkylated phenols in pyrolysis products are clearly indicative of lignin-like compounds. These data represent significant new information on the chemical nature of Protosalvinia and provide the first substantial organic geochemical evidence for land plant affinity. Protosalvinia, Foerstia, Upper Devonian, biostratigraphy, carbon-13 NMR, PY-GC-MS, lignin.

Lethaia↗
USGS1983

Geology of the Devonian black shales of the Appalachian basin

Black shales of Devonian age in the Appalachian basin are a unique rock sequence. The high content of organic matter, which imparts the characteristic lithology, has for years attracted considerable interest in the shales as a possible source of energy. Concurrent with periodic and varied economic exploitations of the black shales are geologic studies. The recent energy shortage prompted the U.S. Department of Energy through the Eastern Gas Shales Project of the Morgantown Energy Technology Center to underwrite a research program to determine the geologic, geochemical, and structural characteristics of the Devonian black shales in order to enhance the recovery of gas from the shales. Geologic studies produced a regional stratigraphic network that correlates the 15-foot sequence in Tennessee with 3,000 feet of interbedded black and gray shales in central New York. The classic Devonian black-shale sequence in New York has been correlated with the Ohio Shale of Ohio and Kentucky and the Chattanooga Shale of Tennessee and southwestern Virginia. Biostratigraphic and lithostratigraphic markers in conjunction with gamma-ray logs facilitated long range correlations within the Appalachian basin and provided a basis for correlations with the black shales of the Illinois and Michigan basins. Areal distribution of selected shale units along with paleocurrent studies, clay mineralogy, and geochemistry suggests variations in the sediment source and transport directions. Current structures, faunal evidence, lithologic variations, and geochemical studies provide evidence to support interpretation of depositional environments. In addition, organic geochemical data combined with stratigraphic and structural characteristics of the shale within the basin allow an evaluation of the resource potential of natural gas in the Devonian shale sequence.

Conference Paper↗
USGS1977

Slope angle distribution of coal beds with strippable reserves

Slope angles were determined in representative strip mining areas of Arizona, Colorado, Illinois, Kentucky, Maryland, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wyoming by personnel of the U.S. Geological Survey to provide the Strip Mining Task Force, assembled by the Council of Environmental Quality, with data relating to the slope angle distribution of coal beds with strippable reserves. For the purpose of this study, slope determinations were made for 22 counties (table 1), selected by the Strip Mining Task Force, for coal beds known to contain strippable reserves as reported by Bureau of Mines Information Circular 8531, "Strippable Reserves of Bituminous Coal and Lignite in the United States." Available geologic maps that delineated coal bed outcrop lines on a topographic base were utilized for most slope angle determinations and coal resource reports provided additional data concerning the areas likely to contain recoverable coal reserves in the selected beds. The angles of slopes along which these coal beds occur were determined by measuring the spacing of topographic contour lines and were assigned to the appropriate slope categories selected for this purpose by the Strip Mining Task Force as follows: (A) 0-10°, (B) 10°-15°, (C) 15°-20°, (D) 20°-25°, and (E) 25°+. The overall sampling technique and measurement procedure are described in the following section and modification to this approach, necessitated by the availability and distribution of data, are described for each county. A list of source material used in compiling slope angles, slope distribution tables, and histograms are also included for each county.

Open-File Report↗