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T.J. Rohrbacher

Publications and source records attributed to T.J. Rohrbacher.

4 recordsLinked to original sources

Quality of Selected Hungarian Coals

As part of a program conducted jointly by the U.S. Geological Survey and the Hungarian Geological Survey under the auspices of the United States-Hungarian Science and Technology Fund, a total of 39 samples from five coal mines in Hungary were selected for analysis. The mine areas sampled represent most of the coal mined recently in Hungary. Almost all the coal is used to generate electricity. Coals from the five mines (four underground, one surface) reflect differences in age, depositional setting, organic and inorganic components of the original sediments, and deformational history. Classified according to the ranking system of the American Society for Testing and Materials, the coals range in rank from lignite B (Pliocene[?] coals) to high volatile A bituminous (Jurassic coals). With respect to grade classification, based on seam-weighted averages of moisture, ash, and sulfur contents: (1) all contain high moisture (more than 10 percent), (2) all except the Eocene coals are high (more than 15 percent) in ash yield, and (3) two (Jurassic and Eocene coals) are high in sulfur (more than 3 percent) and three (Cretaceous, Miocene, and Pliocene coals) have medium sulfur contents (1 to 3 percent). Average heat values range from 4,000 to 8,650 British thermal units per pound.

Scientific Investigations Report↗

Coalbed gas in the Mecsek Basin, Hungary

Information about the presence and recovery of coalbed gas during underground mining and attempts to recover the gas as an energy source, plus new data about gas storage capacity, petrography, maturity, and other coal quality factors, indicate that the coals of the Mecsek Basin may contain large quantities of coalbed gas that is largely methane. Two preliminary estimates of the total gas content of the coalfield are 0.28e+11 m3 (almost 1 trillion cubic feet) and 1.13e+11 m3 (nearly 4 trillion cubic feet). Although much more information is needed about gas contents, permeabilities and other reservoir factors, the available geologic information may be sufficient to identify target areas for exploration. Efforts required to evaluate production potential are warranted. ?? 2003 Elsevier Science B.V. All rights reserved.

International Journal of Coal Geology↗

Economic and environmental evaluations of extractable coal resources conducted by the U. S. Geological Survey

The Economic and Environmental Evaluations of Extractable Coal Resources (E4CR) project integrates economic analyses of extractable coal resources with environmental and coal quality considerations in order to better understand the contribution that coal resources can make to help meet the Nation’s future energy needs. The project utilizes coal resource information derived from the recent National Coal Resource Assessment (NCRA), National Oil and Gas Assessment (NOGA), and Coal Availability and Recoverability Studies (CARS) conducted by the U.S. Geological Survey and other State and Federal cooperating agencies. The E4CR evaluations are designed to augment economic models created by the U.S. Geological Survey CARS and NCRA projects and by the Department of Energy/Energy Information Administration (DOE/EIA). E4CR evaluations are conducted on potentially minable coal beds within selected coalfields in the United States. Emphasis is placed on coalfields containing Federally owned coal and within or adjacent to Federal lands, as shown in U.S. Geological Survey Fact Sheets 012-98, 145-99, and 011-00 (U.S. Geological Survey, 1998, 1999, 2000). Other considerations for the selection of study areas include coal quality, potential environmental impact of coal production activities and coal utilization, the potential for coalbed methane development from the coal, and projected potential for future mining. Completion dates for the E4CR studies loosely follow the schedule for analogous NOGA studies to allow for a comparison of different energy resources in similar geographic areas.

Fact Sheet↗