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Alfred L. Bush

Publications and source records attributed to Alfred L. Bush.

7 recordsLinked to original sources

Reconnaissance study of the geology of U.S. vermiculite deposits: Are asbestos minerals common constituents?

Unusually high incidences of asbestos-related mortality and respiratory disease in the small town of Libby, Montana, have been linked to amphibole mineral fibers intergrown with the vermiculite deposits mined and milled near the town from 1923 to 1990. A study conducted by the U.S. Agency for Toxic Substances and Disease Registry concluded that mortality due to asbestosis in Libby mine and mill workers and residents during 1979 to 1998 was much higher than expected for a similar Montana or United States population group. Recent medical testing of past and present mineworkers and residents of Libby showed lung abnormalities in nearly one-fifth of the adult study participants. The U.S. Environmental Protection Agency, under Superfund authority, is completing sampling and cleanup of asbestos-bearing materials in the mine, mill, and town sites. The U.S. Geological Survey is conducting a study, reviewed herein, to investigate the mineral content of other U.S. vermiculite deposits and to determine if the amphibole asbestos minerals like those found in the Libby deposits are common in other vermiculite deposits.

Montana↗

Mineral resource potential of the Piedra Wilderness Study Area, Archuleta and Hinsdale counties, Colorado

The mineral resource potential of the Piedra Wilderness Study Area is low. No occurrences of metallic minerals, of valuable industrial rocks and minerals, or of useful concentrations of organic fuels are known in the study area. However, a noneconomic occurrence of gypsum in the Jurassic Wanakah Formation lies a few hundred feet west of the WSA boundary, is believed to extend into the WSA, and has a low resource potential. Particular attention was paid to the possible occurrence of organic fuels in the Pennsylvanian Hermosa Formation, of uranium and vanadium in the Jurassic Entrada Sandstone and Morrison Formation, and of coal in the Cretaceous Dakota Sandstone. Thin coaly beds in the Dakota have a low resource potential. Extensive sampling of stream sediments, limited sampling of rock outcrops and springs, and a number of scintillometer traverses failed to pinpoint significant anomalies that might be clues to mineral deposits.

Colorado↗

Mineral resource potential map of the Vermilion Cliffs-Paria Canyon instant study area, Coconino County, Arizona, and Kane County, Utah

In general, the mineral potential of the study area is low; in the past the area has yielded only several hundred tons of uranium ore, and there have been a number of unsuccessful efforts to produce gold. The generally small uraniferous deposits are in the Chinle Formation, mostly in the basal Shinarump Member, and mostly on the east side of the Paria Plateau. To the south and west, around the plateau, the Shinarump host rock pinches out or is present in only a few places, and the same relationships are likely below the plateau, where the host rocks are deeply buried, from 1,500 to 3,000 ft below the surface. These factors suggest the total uranium-copper-vanadium-silver potential to be very low. Gold and mercury occur in very low concentrations in the clayey units of the Petrified Forest Member of the Chinle. Gold concentrations are 40 ppb and less, and the gold is present in very fine particles; recovery is very difficult. Overall, the mercury concentrations are so low that no realistic mineral resource potential can be estimated. Nonmetallic mineral materials of possible value include limestone, flagstone, clay, and gravel, but they are of only local interest. No oil or gas resources are known in the study area. Coal resources within the area are nonexistent, but the Dakota Sandstone does contain coaly beds a few miles to the north. Water is perhaps the most significant resource needed in the study area. A number of perennial springs support the few local ranchers and tourist facilities. Some ground water would be available below the plateau, but drilling depths would be more than 2,000 ft (600-700 m).

Arizona↗

Zeolites in the Pine Ridge Indian Reservation, South Dakota

Zeolites of possible commercial value occur in the Brule Formation of Oligocene age and the Sharps Formation (Harksen, 1961) of Miocene age which crop out in a wide area in the northern part of the Pine Ridge Indian Reservation. The thickness of the zeolite-bearing Interval and the extent of areas within the Interval which contain significant amounts of zeolites are far greater than was expected prior to this investigation. The shape of the zeolite-bearing Interval is tabular and the dimensions of Its exposure are roughly 10 ml x 200 mi x 150 ft (16 km x 160 km x 45 m) thick. Within the study area, there are tracts in which the zeolite resource potential is significant (see pl. 2). This report is intended to inform the Oglala Sioux Tribe of some of the most promising zeolite occurrences. Initial steps can then be taken by the Tribe toward possible development of the resources, should they wish to do so. The data contained herein identify areas of high zeolite potential, but are not adequate to establish economic value for the deposits. If development is recommended by the tribal government, we suggest that the tribal government contact companies involved in research and production of natural zeolites and provide them with the data in this report.

Open-File Report↗