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F. G. Lesure

Publications and source records attributed to F. G. Lesure.

35 records · Page 2Linked to original sources
USGS1982

Mineral resource potential map of the Shining Rock Wilderness, Haywood County, North Carolina

The Shining Rock Wilderness is in the Blue Ridge Mountains of Haywood County, N. C., and is underlain by complexly folded, high-grade metamorphic rocks. These rocks contain a few small, subeconomic deposits of sheet muscovite mica that have a small potential for scrap mica. Quartz as a source of silica (SiO2) and gneiss and schist suitable for common building stone and crushed rock are the only identified economic mineral resources. Other minerals and rocks, including kaolin, soapstone, copper, corundum, and dunite, have been prospected or mined nearby, but either they do not occur or have no current economic potential in the wilderness. A possibility exists for the presence of natural gas at depths greater than 5,000 ft (1,500 m).

North Carolina↗
USGS1982

Mineral resource potential map of the Ramseys Draft Addition, Augusta and Highland counties, Virginia

Under the provisions of the Wilderness Act (Public Law 88-577, September 3, 1964) and the Joint Conference Report on Senate Bill 4, 88th Congress, the U.S. Geological Survey and the U.S. Bureau of Mines have been conducting mineral surveys of wilderness and primitive areas. Areas officially designated as "wilderness," "wild," or "canoe" when the act was passed were incorporated into the National Wilderness Preservation System, and some of them are presently being studied. The act provided that areas under consideration for wilderness designation should be studied for suitability for incorporation into the Wilderness System. The mineral surveys constitute one aspect of the suitability studies. The act directs that the results of such surveys are to be made available to the public and be submitted to the President and the Congress. This report presents the results of a mineral survey of the Ramseys Draft Addition, which is a roadless area adjoining Ramseys Draft Wilderness Study Area in the George Washington National Forest, Augusta and Highland Counties, Virginia. The area was classified as a further planning area during the Second Roadless Area Review and Evaluation (RARE II) by the U.S. Forest Service, January 1979.

Virginia↗
USGS1978

Analyses and descriptions of geochemical samples, Mountain Lake Wilderness Study Area, Virginia and West Virginia

Semiquantitative emission spectrographic analyses for 64 elements on 95 stream sediment and 122 rock samples from Mountain Lake Wilderness Study Area, Giles and Craig Counties, Virginia and Monroe County, West Virginia, are reported here in detail. Locations for all samples are in Universal Transverse Mercator (UTM) coordinates. Brief descriptions of rock samples are also included. Rocks analysed are mostly sandstone. Samples of hematitic sandstone of the Rose Hill Formation and limonite-cemented sandstone of the Rocky Gap Sandstone contain high values of iron; these rocks are submarginal iron resources. Some of these iron-rich samples have a little more barium, copper, cobalt, lead, silver, and/or zinc than in average sandstone, but they do not suggest the presence of economic deposits of these metals. A few samples of Tuscarora Quartzite contain moderate amounts of manganese. These are from a submarginal manganese resource. No other obviously anomalous-values related to mineralized rock are present in the data.

Open-File Report↗
USGS1977

Exploration geochemical studies of some sandstone copper-uranium deposits, Bradford, Columbia, and Lycoming Counties, Pa

Semi-quantitative spectrographic analyses of mineralized and unmineralized sandstone, siltstone, and claystone from the Catskill Formation of Devonian age in Bradford, Columbia, and Lycoming Counties, Pa., suggest that copper, silver, and uranium are the principal metallic elements concentrated in the mineralized rock. Lead, mercury, and molybdenum may be concentrated slightly in mineralized rock but values are too low to be of use in exploration. The deposits are too small to make large anomalies in stream sediments except in drainage basins of less than a few acres. However, if a large deposit were exposed to weathering, it would probably be detectable by stream sediment sampling. Analyses of oxalic acid leachates of the minus 80-mesh fraction of the stream-sediment samples gave more useful values than analyses of the minus 80-mesh samples in separating drainage basins that have copper deposits from those that have no known copper deposits.

Pennsylvania↗
USGS1962

Diffusion features of uranium-vanadium deposits in Montezuma Canyon, Utah

Uranium-vanadium deposits in the Salt Wash Member of the Morrison Formation in Montezuma Canyon , San Juan County, Utah , exhibit zoning that is interpreted as a result of metal transport by diffusion . The concentric zones consist of a brown nonmineralized core, an olive-gray mineralized shell, and a gray nonmineralized outer zone. The brown zone is iron-stained, porous sandstone commonly containing abundant carbonaceous material. The curved mineralized layer completely encloses the brown zone, and is composed of oxidized uranium-vanadium minerals that impregnate sandstone. The gray zone is light-gray sandstone tightly cemented with calcite and commonly freckled with limonitic specks.Formation of the deposits most likely took place during Late Cretaceous or early Tertiary time when the ore-bearing sandstones were deeply buried and saturated with connate waters. The concentration of organic material in the brown zone suggests that this zone was once saturated with a reducing solution containing soluble organic compounds like alcohols and aldehydes derived from the organic material. The gray zone, on the other hand, was probably saturated with an oxidizing solution containing uranium and vanadium. Where these two solutions were in contact, oxidation-reduction reactions took place that caused the precipitation of low-valent uranium and vanadium minerals.The ellipsoidal shape of the ore layer and the lack of any exit or entrance for flowing solutions indicates that the dissolved metals moved through the gray zone by diffusion and were precipitated at the periphery of the reducing zone. Recent weathering and oxidation have altered the primary low-valent minerals to high-valent forms without noticeable leaching of the ore metals.

Utah↗