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• catalog abstract "The Canadian segment of the Archean Superior province is a major world source of lode gold. The gold deposits occur in or near regional transcurrent and oblique slip-shear deformation zones that comprise a conjugate set to a northwest- directed compression of the Superior province. These structures provided permeable pathways for the flow of large volumes of auriferous fluid derived from an external source. Historic gold production from the United States segment of the Superior province is modest, but the close similarity in the geologic environment of the United States and Canadian segments suggests that large gold deposits should be present in the U.S.A. An occurrence model largely based on known parameters of gold mineralization in Canada suggests that the greenstone-granite terranes of the Wawa and Wabigoon sub-provinces in the United States are favorable for important gold deposits. The model suggests that gold mineralization took place during or later than the transcurrent faulting and that it took place contemporaneously with emplacement of silica-undersaturated intrusions. The faulting occurred late in the igneous-tectonic history of the Superior province, about 2,690 Ma. Extensive, intense alteration comprising carbonitization, silicification, and sulfidization accompanied the gold mineralization. The relationships between alteration minerals and mineralized veins suggest a close temporal relationship between the alteration and gold mineralization processes. The proposed occurrence model for gold mineralization and the available data suggest that two broad regions of greenstone in the Archean Superior province in north-central United States are particularly favorable for gold deposits: (1) the Upper Peninsula of Michigan, and (2) northeastern Minnesota. The Ishpeming greenstone belt of the Wawa subprovince in Michigan contains the important Ropes deposit and several other known gold occurrences, and the Vermilion district (Wawa subprovince) in northeastern Minnesota contains highly anomalous gold in soils and minor known bedrock occurrences. Transcurrent faults in both areas should be favorable sites for gold mineralization".
• catalog contributor b3960435.
• catalog contributor b3960436.
• catalog created "1992.".
• catalog date "1992".
• catalog date "1992.".
• catalog dateCopyrighted "1992.".
• catalog description "Includes bibliographical references (p. 17-19).".
• catalog description "The Canadian segment of the Archean Superior province is a major world source of lode gold. The gold deposits occur in or near regional transcurrent and oblique slip-shear deformation zones that comprise a conjugate set to a northwest- directed compression of the Superior province. These structures provided permeable pathways for the flow of large volumes of auriferous fluid derived from an external source. Historic gold production from the United States segment of the Superior province is modest, but the close similarity in the geologic environment of the United States and Canadian segments suggests that large gold deposits should be present in the U.S.A. An occurrence model largely based on known parameters of gold mineralization in Canada suggests that the greenstone-granite terranes of the Wawa and Wabigoon sub-provinces in the United States are favorable for important gold deposits. ".
• catalog description "The Ishpeming greenstone belt of the Wawa subprovince in Michigan contains the important Ropes deposit and several other known gold occurrences, and the Vermilion district (Wawa subprovince) in northeastern Minnesota contains highly anomalous gold in soils and minor known bedrock occurrences. Transcurrent faults in both areas should be favorable sites for gold mineralization".
• catalog description "The model suggests that gold mineralization took place during or later than the transcurrent faulting and that it took place contemporaneously with emplacement of silica-undersaturated intrusions. The faulting occurred late in the igneous-tectonic history of the Superior province, about 2,690 Ma. Extensive, intense alteration comprising carbonitization, silicification, and sulfidization accompanied the gold mineralization. The relationships between alteration minerals and mineralized veins suggest a close temporal relationship between the alteration and gold mineralization processes. The proposed occurrence model for gold mineralization and the available data suggest that two broad regions of greenstone in the Archean Superior province in north-central United States are particularly favorable for gold deposits: (1) the Upper Peninsula of Michigan, and (2) northeastern Minnesota. ".
• catalog extent "iii, 19 p. :".
• catalog isPartOf "Contribution to precambrian geology of Lake Superior Region ; ch. M".
• catalog isPartOf "U.S. Geological Survey bulletin ; 1904-M".
• catalog issued "1992".
• catalog issued "1992.".
• catalog language "eng".
• catalog publisher "[Washington, D.C.] : U.S. G.P.O. ; Denver, CO : For sale by Book and Open-File Report Sales, U.S. Geological Survey Federal Center,".
• catalog spatial "Michigan Upper Peninsula.".
• catalog spatial "Minnesota.".
• catalog subject "557.3 s 553.4/1/09774 20".
• catalog subject "Geology, Stratigraphic Archaean.".
• catalog subject "Gold ores Michigan Upper Peninsula.".
• catalog subject "Gold ores Minnesota.".
• catalog subject "Greenstone belts Michigan Upper Peninsula.".
• catalog subject "Greenstone belts Minnesota.".
• catalog subject "QE75 .B9 no. 1904-M QE390.2.G65".
• catalog title "A regional structural model for gold mineralization in the southern part of the Archean Superior Province, United States / by P.K. Sims and W.C. Day.".
• catalog type "text".