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At least 649 records · Page 36Linked to original sources
USGS1998

Contributions to the gold metallogeny of northern Nevada

Nevada is one of the Earth's premier gold producing regions, accounting for approximately 64 percent of the U.S and nine percent of the world total. The impact of these mines on nearby local economies and on our national balance of payments is profound, and will continue well into the next century. Of principal importance in this region are giant sedimentary-rock-hosted (Carlin-type) deposits. These are some of the world's largest deposits, but yet are poorly understood. Other sedimentary-rock hosted deposits in the region, the distal-disseminated Ag-Au type, are genetically related to shallow plutonic complexes. Hot-spring gold-silver systems associated with Tertiary volcanic rocks represent a third type of precious metal deposit in northern Nevada. These deposits, despite being generally smaller than sedimentary-rock-hosted gold deposits, are also important gold-silver resources. Aspects about the geologic and metallogenic setting of gold-silver deposits in northern Nevada are addressed in the twenty-two chapters that compose this volume. The volume is organized along four themes: (1) crustal structure; (2) Carlin-type deposits; (3) pluton-related gold-silver deposits near Battle Mountain; and (4) hot-spring gold-silver deposits. This Open-File Report, the result of ongoing geologic and mineral-resource investigations, provides a basis for mineral exploration, for land-use planning decisions, and for environmental questions in northern Nevada.

Open-File Report↗
USGS1998

Contributions to the gold metallogeny of northern Nevada

Nevada is one of the Earth's premier gold producing regions, accounting for approximately 64 percent of the U.S and nine percent of the world total. The impact of these mines on nearby local economies and on our national balance of payments is profound, and will continue well into the next century. Of principal importance in this region are giant sedimentary-rock-hosted (Carlin-type) deposits. These are some of the world's largest deposits, but yet are poorly understood. Other sedimentary-rock hosted deposits in the region, the distal-disseminated Ag-Au type, are genetically related to shallow plutonic complexes. Hot-spring gold-silver systems associated with Tertiary volcanic rocks represent a third type of precious metal deposit in northern Nevada. These deposits, despite being generally smaller than sedimentary-rock-hosted gold deposits, are also important gold-silver resources. Aspects about the geologic and metallogenic setting of gold-silver deposits in northern Nevada are addressed in the twenty-two chapters that compose this volume. The volume is organized along four themes: (1) crustal structure; (2) Carlin-type deposits; (3) pluton-related gold-silver deposits near Battle Mountain; and (4) hot-spring gold-silver deposits. This Open-File Report, the result of ongoing geologic and mineral-resource investigations, provides a basis for mineral exploration, for land-use planning decisions, and for environmental questions in northern Nevada.

Open-File Report↗
USGS1918

Shorter contributions to general geology, 1917

Contents: A. Baked shale and slag formed by the burning of coal beds / G.S. Rogers B. The Newington moraine, Maine, New Hampshire, and Massachusetts / F.J. Katz and Arthur Keith C.A comparison of Paleozoic sections in southern New Mexico / N.H. Darton D. Wasatch fossils in so-called Fort Union beds of the Powder River Basin, Wyo., and their bearing on the stratigraphy of the region / C.H. Wegemann E. Geologic history indicated by the fossiliferous deposits of the Wilcox group at Meridian, Miss. / E.W. Berry F.A fossil flora from the Frontier formation of southwestern Wyoming / F.H. Knowlton G. The stratigraphic position and faunal associates of the orbitoid Foraminifera of the genus Orthophragmina from Georgia and Florida / C.W. Cooke G. Orbitoid Foraminifera of the genus Orthophragmina from Georgia and Florida / J.A. Cushman H. The Pliocene history of northern and central Mississippi / E.W. Shaw I. Stratigraphy in northwestern Maine and southeastern New Hampshire / F.J. Katz J. The Flaxville gravel and its relation to other terrace gravels of the northern Great Plains / A.J. Collier K. The Helderberg limestone of central Pennsylvania / J.B. Reeside L. Stratigraphy of the Hanna Basin, Wyo. / C.F. Bowen

Professional Paper↗