Geology topics

Dorothy A. Taylor

Publications and source records attributed to Dorothy A. Taylor.

3 recordsLinked to original sources

USGS1953

Coal resources of the United States (a progress report, October 1, 1953)

As estimated in this second progress report, the coal reserves of the United States remaining in the ground on January 1, 1953, total 1,899,739 million tons. This figure is about a 20 percent reduction of the total estimate published in the first progress report (Averitt and Berryhill, 1950). The new total is based on new, detailed, conservative estimates of reserves in Indiana, Michigan, Montana, New Mexico, North Carolina, North Dakota, South Dakota, Virginia, and Wyoming, prepared since 1947 by the U. S. Geological Survey; on new provisional, but equally conservative estimates of reserves in Colorado, Maryland, and Georgia, based on previous work of the U. S. Geological Survey and other agencies; on estimates of reserves in Illinois, Kansas, Pennsylvania, and West Virginia, prepared by the geological surveys of those States; and on older and incompletely documented estimates for the remaining states. The older estimates were prepared on a highly generalized basis and were intended to represent total possible reserves in both thick and thin beds and under both light and heavy overburden. The recent estimates have been prepared on a more conservative basis than the older estimates and tend to be considerably smaller. New conservative estimates have now been prepared for 16 coal-bearing States, which include about two-thirds of the total estimated reserves of the United States. As new estimates are prepared for the remaining States a further reduction of the total reserve figure is in prospect, though the reserves still will be large. The estimated recoverable reserves of the United States as of January 1, 1953, total 949,870 million tons, based on the assumption that half of the coal reserves in the ground will be lost in mining, and half will be recovered. The distribution of the remaining and recoverable reserves by rank is shown in the accompanying table. The reserves in 10 States have been classified in considerable detail according to thickness of beds, thickness of overburden, and relative abundance of reliable information available for making estimates. In these States, which are representative of several coal provinces, and contain about 40 percent of the total reserves, and are thus typical of the United States as a whole, 5 percent of the total is measured reserves in beds 28 inches or more thick, and less than 1,000 feet below the surface; and 20 percent is indicated reserves within the same limit of thickness and less than 2,000 feet below the surface. The remaining 75 percent is inferred reserves, reserves in thin beds, and reserves 2,000 to 3,000 feet below the surface. The large percentage of inferred reserves obviously includes some coal in thick beds, which for lack of detailed information cannot be appraised quantitatively. Although accurately based on the data now available, the distribution percentages are subject to considerable change as new work is completed, particularly in the transfer of reserves from the indicated and inferred categories to the measured category. The figures serve, however, to indicate the present state of knowledge of the Nation's coal reserves, and they point to the need for additional geologic mapping and exploration.

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USGS1952

Coal resources of Virginia

The U. S. Geological Survey and the Virginia Geological Survey have cooperated in preparing this reappraisal of the coal resources of Virginia, which is based on a study of all information" on the reserves of the State available in the publications and files of the two organizations, supplemented by mine and drill-hole information provided by mining companies and private individuals. Coal is found in Virginia in three widely separated and entirely dissimilar areas: the Southwest Virginia field, or simply the Southwest field, which comprises all or part of Tazewell, Buchanan, Dickenson, Russell, Scott, Wise, and Lee Counties; the Valley fields, a series of long, narrow coal-bearing areas in the Valley of Virginia that are concentrated largely in Montgomery, Pulaski, and Wythe Counties; and the Eastern fields, consisting of two relatively small basins near Richmond and Farmville, respectively. Of the total reserves of the State, about 97 percent are in the Southwest Virginia field. In estimating reserves of the Southwest Virginia field the cooperating agencies were assisted by a series of excellent county reports covering the entire field and by the generous cooperation received from the coal-mining companies. Because of this help, it was possible not only to prepare estimates of reserves in that field by individual coal beds, but to outline most of the important mined-out areas on the bed maps and thus to prepare an estimate that takes into consideration the coal mined and lost in mining prior to January 1, 1951. The Valley fields, which were mined to some extent prior to 1860 and which have an almost continuous production record since 1883, have been mapped and studied in some detail, but the data on the area are in general inadequate and the structure is too complex to permit a detailed estimate of reserves. Estimates of indicated and inferred reserves in six. of the ten Valley fields were prepared, however, and are presented in subsequent pages. The estimates for the Valley fields are on the basis of original reserves, as mine information is too scanty and production figures too generalized to be of value in translating original reserves into remaining reserves. The Richmond basin, the easternmost of the Eastern fields, was first mined in 1748, and operations were carried on almost continuously for 150 yr of more after that date. Activity died rapidly as rail transportation made the more easily mined Appalachian coals available, and the Eastern basins have seen little activity since about 1905. Despite the fact that an all-time total of more than 8 million tons has been taken from the Richmond basin, the data now available on the coal beds are considerably less than those on the Valley fields and it was impossible to estimate the reserves with any degree of accuracy. The reserves of the Eastern fields are therefore omitted from the tables, though the fields are discussed in later sections of this report. Whether presented as remaining reserves (Southwest field) or original reserves (Valley fields) the estimates presented in this report have been calculated on a most conservative basis, and in all probability these estimates will be increased rather than diminished as additional field work is done. Undoubtedly much of the coal reserves shown herein as indicated or inferred reserves will be changed to the measured or indicated category as development work progresses.

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USGS1950

Coal resources of Wyoming

The Antlers aquifer, which consists of as much as 900 feet of friable sandstone, silt, clay, and shale crops out in areas of 1 ,860 square miles and underlies about 4,400 square miles in southeastern Oklahoma. Precipitation ranges from 34 to 50 inches per year across the outcrop area which is well suited to allow high rates of infiltration. The aquifer contains an estimated 70 ,000,000 acre-feet of water having less than 1,000 milligrams per liter dissolved solids. The average saturated thickness is 250 feet. Aquifer tests indicate the average transmissivity is 1 ,480 feet squared per day and the average storage coefficient is 0.0005. Large capacity wells tapping the aquifer commonly yield 100 to 500 gallons per minute; the maximum measured yield is 1 ,700 gallons per minute. Water usage from the aquifer is very small owing to an abundance of surface water. Water quality throughout the central and northern part of the aquifer is generally acceptable for municipal use. However, a few wells yield water containing concentrations of iron and manganese exceeding the limit recommended by the National Academy of Science for municipal use. (USGS)

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