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Vincent E. McKelvey

Publications and source records attributed to Vincent E. McKelvey.

5 recordsLinked to original sources
USGS1985

U. S. PHOSPHATE INDUSTRY: REVISED PROSPECTS AND POTENTIAL.

Although the United States is the world's largest producer and exporter of phosphates, serious doubts have arisen in recent years that U. S. deposits could sustain this important role. The development of borehole mining; i. e. , extracting the phosphate matrix as a slurry through a drill hole, however, is cause for optimism. Commercial borehole mining is still years away, but the potential advantages are numerous and important. Recent surveys also suggest that offshore deposits and deeply buried onshore deposits much exceed previous estimates. On the basis of the new technology and revised resource estimates, one can easily see the potential for increased production from U. S. deposits.

Marine Technology Society Journal↗
USGS1974

New activities at the U.S. Geological Survey

As the Nation's principal source of information about the configuration of the land surface, the composition and structure of the rocks at and beneath the surface, the distribution and character of its energy, mineral, and water resources, and the nature of natural geologic processes, the U. S. Geological Survey focuses its work on some of the Nation's most critical problems. As the Survey tackles new problems with new techniques, it is fully aware of the resource needs and environmental pressures of an expanding economy and growing population.

General Information Product↗
USGS1950

Value of domestic production of minerals from various classes of rocks

Fluids and sedimentary rocks accounted for 48 and 36 percent, respectively, of the total value of the 1946 domestic mineral production. The epigenetic (vein and replacement) and metamorphic deposits each contributed 6 percent of the total, and residual and igneous deposits accounted for 3 and 1 percent, respectively. Fuels were the most valuable of all the minerals produced--77 percent of the total. Petroleum, natural gas, and similar fluid fuels accounted for 47 percent of the total production and 98 percent of that from fluids; bituminous coal made up 24 percent of the total production and 67 percent of that from sedimentary rocks; anthracite coal was valued at 6 percent of the total production and 92 percent of that from metamorphic rocks. Exclusive of fuels, the bulk of the production of nonmetallics, and of the total mineral production too, was from sedimentary rocks (74 and 50 percent, respectively) and from veins and replacements (8 and 28 percent, respectively). Most of the production of metals, however, was from veins, etc. (62 percent) and residuum (29 percent).

Economic Geology↗
USGS1950

Characteristics of marine uranium-bearing sedimentary rocks

Many marine sedimentary black shale and phosphorite formations contain 0.01 to 0.02 percent uranium, and one, the alum shale of Sweden, contains as much as 0.5 percent. The published fact that uranium is already being recovered on a laboratory scale from Swedish deposits forcefully suggests that similar deposits in the United States and possibly many other countries may prove to be an important future source of uranium.The marine uranium-bearing black shales are rich in organic matter and sulfides and contain little or no carbonate. The best are found in relatively thin formations of pre-Mesozoic age. The nature of the uranium-bearing mineral or compound is not known. In contrast, nonmarine black shales, as a group, are not uraniferous.All marine phosphorites tested thus far are uraniferous and so too are the phosphatic nodules found in many marine black shales. With some exceptions, the uranium increases in a general way with increase in phosphate content and is believed to be in the phosphate mineral. Like the black shales, the phosphorite formations are characteristically thin; many are associated with unconformities or, in other words, periods during which little else in the way of sediment accumulated.Significant concentrations of uranium in marine sediments other than black shales and phosphorites are thus far known only in beach placer deposits and the gold-bearing conglomerates of the Witwatersrand district, South Africa.Uranium may be found in other types of marine sediments on further prospecting, but especially promising are the sediments rich in organic matter, phosphate, or both, found in relatively thin formations believed to be the entire depositional products of long periods of geologic time. Such formations are most characteristic of those areas where, at the time of deposition, the adjacent land masses were so stable and low that the influx of clastic materials was small; the basin of deposition was large or of such configuration that fine-grained sediments could accumulate; and chemical conditions in the seawater prevented deposition of large amounts of carbonate.

Economic Geology↗