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Environmental Geochemical Studies of Selected Mineral Deposits in Wrangell-St. Elias National Park and Preserve, Alaska

Description: From abstract: Environmental geochemical investigations took place in Wrangell-St. Elias National Park and Preserve (WRST), Alaska, between 1994 and 1997. Areas studied include the historic Kennecott stratabound copper mines and mill area; the historic mines and mill in the Bremner district, where gold was produced from polymetallic veins; the sporadically active gold placer mines at Gold Hill; the undisturbed, unmined porphyry copper-molybdenum deposits at Orange Hill and Bond Creek; and the historic mines and mill at Nabesna, where gold-bearing iron skarn deposits were exploited. The cooperative study between the U.S. Geological Survey and the National Park Service focused on identifying and characterizing geochemical signatures associated with these mineralized areas. Sample media included surface water, bedload sediment, rock, mine waste, and mill tailings samples.
Date: 2000
Creator: Eppinger, Robert G.; Briggs, Paul H.; Rosenkrans, Danny S. & Ballestrazze, Vanessa
Partner: UNT Libraries Government Documents Department

[Evolution of Sedimentary Basins/Onshore Oil and Gas Investigations--Santa Maria Province: Chapters Y and Z]

Description: From abstract: A complex Neogene history characterizes the offshore Santa Maria basin and the northwest margin of the western Transverse Ranges, California. This history includes the transition from subduction to a transtensional and then transpressional plate boundary, including about 900 of clockwise rotation of the western Transverse Ranges. This report uses seismic reflection data to document the geometry of structures that accommodated this deformation and offshore well data to date and correlate the sediments which were affected by the different tectonic episodes.
Date: 1999
Creator: Sorlien, Christopher C.; Nicholson, Craig; Luyendyk, Bruce P.; Miller, Kate C. & Meltzer, Anne S.
Partner: UNT Libraries Government Documents Department

[Evolution of Sedimentary Basins/Onshore Oil and Gas Investigations--Santa Maria Province: Chapters W and X]

Description: From abstract: Bulletin W is about the deformation of the Mesozoic Franciscan Complex of the Eastern Santa Maria basin in California. Bulletin X is about the regional thermal maturity of the surface rocks of the mentioned basin as well as the Santa Barbara-Ventura basin area in California.
Date: 1998
Creator: Wahl, Arthur D.; Naeser, Nancy D.; Isaacs, Caroline M. & Keller, Margaret A.
Partner: UNT Libraries Government Documents Department

Laccolith Complexes of Southeastern Utah: Time of Emplacement and Tectonic Setting Workshop Proceedings

Description: This report summarizes much of the materials presented at the workshop and provides an extensive list of selected references pertaining to geochronology and tectonics of the Colorado Plateau to facilitate further research.
Date: 1998
Creator: Friedman, Jules D. & Huffman, Curtis Jr.
Partner: UNT Libraries Government Documents Department

Lateral Ramps in the Folded Appalachians and in Overthrust Belts Worldwide—A Fundamental Element of Thrust-Belt Architecture

Description: A report about lateral ramps which are zones where décollements change stratigraphic level along a strike. This report suggests that many cross-strike features may be underlain by lateral ramps that serve to transfer décollements from one stratigraphic level to another in the same manner as frontal ramp, but in a direction normal to the strike of the fold belt.
Date: 1998
Creator: Pohn, Howard A.
Partner: UNT Libraries Government Documents Department

Geology of the Pennsylvanian and Permian Cutler Group and Permian Kaibab Limestone in the Paradox Basin, Southeastern Utah and Southwestern Colorado

Description: From abstract: This report talks about the geology of the Pennsylvanian and Permian Cutler Group that consists of the lower Cutler beds, Cedar Mesa Sandstone, Organ Rock Formation, White Rim Sandstone, and De Chelly Sandstone. The report also talks about the Permian Kaibab Limestone in the Paradox Basin that overlays the Cutler.
Date: 1997
Creator: Condon, Steven M.
Partner: UNT Libraries Government Documents Department

Paleomagnetic and 40Ar/39Ar Results from the Grant Intrusive Breccia and Comparison to the Permian Downeys Bluff Sill—Evidence for Permian Igneous Activity at Hicks Dome, Southern Illinois Basin

Description: A report about applying 40Ar/39Ar dating methods, along with other rock techniques, to determine the age of emplacement and the cooling history of the Grant intrusive breccia at Hicks dome in Illinois.
Date: 1997
Creator: Reynolds, Richard L.; Goldhaber, Martin B. & Snee, Lawrence W.
Partner: UNT Libraries Government Documents Department

The Sedimentary Carbonate-Hosted Giant Bayan Obo REE-Fe-Nb Ore Deposit of Inner Mongolia, China: A Cornerstone Example for Giant Polymetallic Ore Deposits of Hydrothermal Origin

Description: A report which describes the overall characteristics of Bayan Obo ore deposit. The paper examines Bayan Obo as a cornerstone example of giant ore deposits of hydrothermal origin.
Date: 1997
Creator: Chao, E. C. T.
Partner: UNT Libraries Government Documents Department

Chronology of Late Cretaceous Igneous and Hydrothermal Events at the Golden Sunlight Gold-Silver Breccia Pipe, Southwestern Montana

Description: A report about gold mineralization at the Golden Sunlight breccia pipe, southwestern Montana, is related to emplacement of Late Cretaceous alkali-calcic rhyolite and subsequent collapse of the Belt Supergroup wallrock and rhyolite in the pipe.
Date: 1996
Creator: DeWitt, Ed; Foord, Eugene E.; Zartman, Robert E.; Pearson, Robert C. & Foster, Fess
Partner: UNT Libraries Government Documents Department

Geologic Processes at the Land Surface

Description: A report about erosion, deposition, soil formation, and water flow. It discusses hazards such as landslides, dust storms, floods, topsoil loss, ecosystem change, water contamination, and soil contamination.
Date: 1996
Creator: Wilshire, Howard G.; Howard, Keith A.; Wentworth, Carl M. & Gibbons, Helen
Partner: UNT Libraries Government Documents Department