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Page 5479, results 136951 - 136975

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Publication Extents

Not all publications have extents, not all extents are completely accurate
A mineralogical study of the Guanajuato, Mexico, silver ores
Ivan Franklin Wilson, Charles Milton, Joseph Rollins Houston
1975, Open-File Report 75-70
The silver-gold ores now being worked in the Guanajuato, Mexico, mining district consist chiefly of argentite and native gold-silver, with minor amounts of polybasite, pyrargyrite, and some argyrodite, a silver germanium sulfide. With these are always associated galena, sphalerite, chalcopyrite, pyrite, and minor amounts of marcasite. The gangue is generally...
Geology, physical properties, and surface effects at Discus Thrower Site, Yucca Flat, Nevada test site
Wilfred James Carr, C.H. Miller, Harry W. Dodge
1975, Open-File Report 75-410
Geologic studies in connection with Project Discus Thrower have furnished detailed stratigraphic and structural information about northwestern Yucca Flat. The Paleozoic rocks consist of a lower carbonate sequence, argillite of the Eleana Formation, and an upper carbonate sequence. The distribution of these rocks suggests that both top and bottom of...
Niobium (columbium) and tantalum resources of Brazil
Max Gregg White
1975, Open-File Report 75-29
Most of the niobium resources of Brazil occur as pyrochlore in carbonatites within syenitic intrusives of Late Cretaceous to early Tertiary age in western Minas Gerais and southeastern Goils. Minor amounts of it are produced together with tantalum from columbite-tantalite concentrates from pegmatites and placers adjacent to them, in the...
Aluminum resources of Brazil
Max Gregg White
1975, Open-File Report 75-30
Large deposits of bauxite, the principal ore of aluminum, occur at several places in Brazil. The largest deposits now undergoing extensive exploration and development are in the eastern Amazon Basin. Most of these deposits are in the State of Para, but some are in Amazonas and Maranhao.Discovery of large-scale resources...
A model for earthquakes near Palisades Reservoir, southeast Idaho
David L. Schleicher
1975, Open-File Report 75-12
The Palisades Reservoir seems to be triggering earthquakes: epicenters are concentrated near the reservoir, and quakes are concentrated in spring, when the reservoir level is highest or is rising most rapidly, and in fall, when the level is lowest. Both spring and fall quakes appear to be triggered by minor...
Structure of continental margin off Mid-Atlantic states (Baltimore Canyon Trough)
John Stevens Schlee, John Charles Behrendt, Robert E. Mattick, P. T. Taylor
1975, Open-File Report 75-60
Increasing interest in the Atlantic continental margin as a future petroleum province has resulted in several recent papers (Emmerich, 1974; Burk and Drake, 1974) that attempt to summarize the structure and stratigraphic framework of this area. Most papers tend to portray the margin as a wedge of Mesozoic and Cenozoic...
Hydrology of sand-and-gravel aquifer in central and southern Escambia County, Florida
Henry Trapp Jr.
1975, Open-File Report 74-218
The sand-and-gravel aquifer is the only fresh-water aquifer in the Pensacola area. Problems related to development of the aquifer include maximum safe yield, local contamination, local salt-water intrusion, corrosiveness of the water, areas of high iron concentration, and increasing nitrate concentration. The city of Pensacola is seeking hydrologic information, including...
Self-calibrating seismic amplifier and telemetry system
John R. Van Schaack
1975, Open-File Report 75-64
A frequency modulated, constant bandwidth, telemetry system has been designed to transmit simultaneously up to 8 channels of seismograph data from remote locations to a central recording site via radio or voice-grade telephone circuit. By utilizing state-of-the-art integrated circuits, the size of the remote unit has been considerably reduced over...