Robert R. Seal
Robert (Bob) Seal is a Research Geologist with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.
Science and Products
Filter Total Items: 24
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Stratiform chromite deposit model
Stratiform chromite deposits are of great economic importance, yet their origin and evolution remain highly debated. Layered igneous intrusions such as the Bushveld, Great Dyke, Kemi, and Stillwater Complexes, provide opportunities for studying magmatic differentiation processes and assimilation within the crust, as well as related ore-deposit formation. Chromite-rich seams within layered intrusio
Authors
Ruth F. Schulte, Ryan D. Taylor, Nadine M. Piatak, Robert R. Seal
Magmatic sulfide-rich nickel-copper deposits related to picrite and (or) tholeiitic basalt dike-sill complexes: A preliminary deposit model
Magmatic sulfide deposits containing nickel (Ni) and copper (Cu), with or without (±) platinum-group elements (PGEs), account for approximately 60 percent of the world’s Ni production and are active exploration targets in the United States and elsewhere. On the basis of their principal metal production, magmatic sulfide deposits in mafic rocks can be divided into two major types: those that are su
Authors
Klaus J. Schulz, Val W. Chandler, Suzanne W. Nicholson, Nadine M. Piatak, Robert R. Seal, Laurel G. Woodruff, Michael L. Zientek
An occurrence model for the national assessment of volcanogenic beryllium deposits
The general occurrence model summarized here is intended to provide a descriptive basis for the identification and assessment of undiscovered beryllium deposits of a type and style similar to those found at Spor Mountain, Juab County, Utah. The assessment model is restricted in its application in order to provide a coherent basis for assessing the probability of the occurrence of similar economic
Authors
Nora K. Foley, Robert R. Seal, Nadine M. Piatak, Brianna Hetland
Porphyry copper deposit model
This report contains a revised descriptive model of porphyry copper deposits (PCDs), the world's largest source (about 60 percent) and resource (about 65 percent) of copper and a major source of molybdenum, gold and silver. Despite relatively low grades (average 0.44 percent copper in 2008), PCDs have significant economic and societal impacts due to their large size (commonly hundreds of millions
Authors
Robert A. Ayuso, Mark D. Barton, Richard J. Blakely, Robert J. Bodnar, John H. Dilles, Floyd Gray, Fred T. Graybeal, John L. Mars, Darcy McPhee, Robert R. Seal, Ryan D. Taylor, Peter G. Vikre
Mineralogy and the release of trace elements from slag from the Hegeler Zinc smelter, Illinois (USA)
Slag from the former Hegeler Zn-smelting facility in Illinois (USA) is mainly composed of spinifex Ca-rich plagioclase, fine-grained dendritic or coarse-grained subhedral to anhedral clinopyroxenes, euhedral to subhedral spinels, spherical blebs of Fe sulfides, silicate glass, and less commonly fayalitic olivine. Mullite and quartz were also identified in one sample as representing remnants of the
Authors
Nadine M. Piatak, Robert R. Seal
Aquatic assessment of the Ely Copper Mine Superfund site, Vershire, Vermont
The Ely Mine, which operated from 1821 to 1905, and its area of downstream impact constitute the Ely Copper Mine Superfund site. The site was placed on the National Priorities List in 2001. The mine comprises underground workings, foundations from historical structures, several waste-rock piles, roast beds associated with the smelting operation, and slag piles resulting from the smelting. The mine
Authors
Robert R. Seal, Richard G. Kiah, Nadine M. Piatak, John M. Besser, James F. Coles, Jane M. Hammarstrom, Denise M. Argue, Denise M. Levitan, Jeffrey R. Deacon, Christopher G. Ingersoll
A New Occurrence Model for National Assessment of Undiscovered Volcanogenic Massive Sulfide Deposits
Volcanogenic massive sulfide (VMS) deposits are very significant current and historical resources of Cu-Pb-Zn-Au-Ag, are active exploration targets in several areas of the United States and potentially have significant environmental effects. This new USGS VMS deposit model provides a comprehensive review of deposit occurrence and ore genesis, and fully integrates recent advances in the understandi
Authors
W.C. Pat Shanks, Cynthia Dusel-Bacon, Randolph Koski, Lisa A. Morgan, Dan Mosier, Nadine M. Piatak, Ian Ridley, Robert R. Seal, Klaus J. Schulz, John F. Slack, Roland Thurston
Preliminary model of porphyry copper deposits
The U.S. Geological Survey (USGS) Mineral Resources Program develops mineral-deposit models for application in USGS mineral-resource assessments and other mineral resource-related activities within the USGS as well as for nongovernmental applications. Periodic updates of models are published in order to incorporate new concepts and findings on the occurrence, nature, and origin of specific mineral
Authors
Byron R. Berger, Robert A. Ayuso, Jeffrey C. Wynn, Robert R. Seal
Selected Water- and Sediment-Quality, Aquatic Biology, and Mine-Waste Data from the Ely Copper Mine Superfund Site, Vershire, VT, 1998-2007
The data contained in this report are a compilation of selected water- and sediment-quality, aquatic biology, and mine-waste data collected at the Ely Copper Mine Superfund site in Vershire, VT, from August 1998 through May 2007. The Ely Copper Mine Superfund site is in eastern, central Vermont (fig. 1) within the Vermont Copper Belt (Hammarstrom and others, 2001). The Ely Copper Mine site was pla
Authors
Denise M. Argue, Richard G. Kiah, Nadine M. Piatak, Robert R. Seal, Jane M. Hammarstrom, Edward Hathaway, James F. Coles
Surface-Water Hydrology and Quality at the Pike Hill Superfund Site, Corinth, Vermont, October 2004 to December 2005
The hydrology and quality of surface water in and around the Pike Hill Brook watershed, in Corinth, Vermont, was studied from October 2004 to December 2005 by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency (USEPA). Pike Hill was mined intermittently for copper from 1847 to 1919 and the site is known to be contributing trace elements and acidity to Pike Hill
Authors
Richard G. Kiah, Jeffrey R. Deacon, Nadine M. Piatak, Robert R. Seal, James F. Coles, Jane M. Hammarstrom
Geochemical and mineralogical characterization of the abandoned Valzinco (lead-zinc) and Mitchell (gold) mine sites prior to reclamation, Spotsylvania County, Virginia
The Virginia gold-pyrite belt, part of the central Virginia volcanic-plutonic belt, hosts numerous abandoned metal mines. The belt extends from about 50 km south of Washington, D.C., for approximately 175 km to the southwest into central Virginia. The rocks that comprise the belt include metamorphosed volcanic and clastic (noncarbonate) sedimentary rocks that were originally deposited during the O
Authors
Jane M. Hammarstrom, Adam N. Johnson, Robert R. Seal, Allen L. Meier, Paul L. Briggs, Nadine M. Piatak
Geochemical Characterization of Mine Waste, Mine Drainage, and Stream Sediments at the Pike Hill Copper Mine Superfund Site, Orange County, Vermont
The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial investigati
Authors
Nadine M. Piatak, Robert R. Seal, Jane M. Hammarstrom, Richard G. Kiah, Jeffrey R. Deacon, Monique Adams, Michael W. Anthony, Paul H. Briggs, John C. Jackson
Science and Products
Filter Total Items: 24
No Result Found
Filter Total Items: 93
Stratiform chromite deposit model
Stratiform chromite deposits are of great economic importance, yet their origin and evolution remain highly debated. Layered igneous intrusions such as the Bushveld, Great Dyke, Kemi, and Stillwater Complexes, provide opportunities for studying magmatic differentiation processes and assimilation within the crust, as well as related ore-deposit formation. Chromite-rich seams within layered intrusio
Authors
Ruth F. Schulte, Ryan D. Taylor, Nadine M. Piatak, Robert R. Seal
Magmatic sulfide-rich nickel-copper deposits related to picrite and (or) tholeiitic basalt dike-sill complexes: A preliminary deposit model
Magmatic sulfide deposits containing nickel (Ni) and copper (Cu), with or without (±) platinum-group elements (PGEs), account for approximately 60 percent of the world’s Ni production and are active exploration targets in the United States and elsewhere. On the basis of their principal metal production, magmatic sulfide deposits in mafic rocks can be divided into two major types: those that are su
Authors
Klaus J. Schulz, Val W. Chandler, Suzanne W. Nicholson, Nadine M. Piatak, Robert R. Seal, Laurel G. Woodruff, Michael L. Zientek
An occurrence model for the national assessment of volcanogenic beryllium deposits
The general occurrence model summarized here is intended to provide a descriptive basis for the identification and assessment of undiscovered beryllium deposits of a type and style similar to those found at Spor Mountain, Juab County, Utah. The assessment model is restricted in its application in order to provide a coherent basis for assessing the probability of the occurrence of similar economic
Authors
Nora K. Foley, Robert R. Seal, Nadine M. Piatak, Brianna Hetland
Porphyry copper deposit model
This report contains a revised descriptive model of porphyry copper deposits (PCDs), the world's largest source (about 60 percent) and resource (about 65 percent) of copper and a major source of molybdenum, gold and silver. Despite relatively low grades (average 0.44 percent copper in 2008), PCDs have significant economic and societal impacts due to their large size (commonly hundreds of millions
Authors
Robert A. Ayuso, Mark D. Barton, Richard J. Blakely, Robert J. Bodnar, John H. Dilles, Floyd Gray, Fred T. Graybeal, John L. Mars, Darcy McPhee, Robert R. Seal, Ryan D. Taylor, Peter G. Vikre
Mineralogy and the release of trace elements from slag from the Hegeler Zinc smelter, Illinois (USA)
Slag from the former Hegeler Zn-smelting facility in Illinois (USA) is mainly composed of spinifex Ca-rich plagioclase, fine-grained dendritic or coarse-grained subhedral to anhedral clinopyroxenes, euhedral to subhedral spinels, spherical blebs of Fe sulfides, silicate glass, and less commonly fayalitic olivine. Mullite and quartz were also identified in one sample as representing remnants of the
Authors
Nadine M. Piatak, Robert R. Seal
Aquatic assessment of the Ely Copper Mine Superfund site, Vershire, Vermont
The Ely Mine, which operated from 1821 to 1905, and its area of downstream impact constitute the Ely Copper Mine Superfund site. The site was placed on the National Priorities List in 2001. The mine comprises underground workings, foundations from historical structures, several waste-rock piles, roast beds associated with the smelting operation, and slag piles resulting from the smelting. The mine
Authors
Robert R. Seal, Richard G. Kiah, Nadine M. Piatak, John M. Besser, James F. Coles, Jane M. Hammarstrom, Denise M. Argue, Denise M. Levitan, Jeffrey R. Deacon, Christopher G. Ingersoll
A New Occurrence Model for National Assessment of Undiscovered Volcanogenic Massive Sulfide Deposits
Volcanogenic massive sulfide (VMS) deposits are very significant current and historical resources of Cu-Pb-Zn-Au-Ag, are active exploration targets in several areas of the United States and potentially have significant environmental effects. This new USGS VMS deposit model provides a comprehensive review of deposit occurrence and ore genesis, and fully integrates recent advances in the understandi
Authors
W.C. Pat Shanks, Cynthia Dusel-Bacon, Randolph Koski, Lisa A. Morgan, Dan Mosier, Nadine M. Piatak, Ian Ridley, Robert R. Seal, Klaus J. Schulz, John F. Slack, Roland Thurston
Preliminary model of porphyry copper deposits
The U.S. Geological Survey (USGS) Mineral Resources Program develops mineral-deposit models for application in USGS mineral-resource assessments and other mineral resource-related activities within the USGS as well as for nongovernmental applications. Periodic updates of models are published in order to incorporate new concepts and findings on the occurrence, nature, and origin of specific mineral
Authors
Byron R. Berger, Robert A. Ayuso, Jeffrey C. Wynn, Robert R. Seal
Selected Water- and Sediment-Quality, Aquatic Biology, and Mine-Waste Data from the Ely Copper Mine Superfund Site, Vershire, VT, 1998-2007
The data contained in this report are a compilation of selected water- and sediment-quality, aquatic biology, and mine-waste data collected at the Ely Copper Mine Superfund site in Vershire, VT, from August 1998 through May 2007. The Ely Copper Mine Superfund site is in eastern, central Vermont (fig. 1) within the Vermont Copper Belt (Hammarstrom and others, 2001). The Ely Copper Mine site was pla
Authors
Denise M. Argue, Richard G. Kiah, Nadine M. Piatak, Robert R. Seal, Jane M. Hammarstrom, Edward Hathaway, James F. Coles
Surface-Water Hydrology and Quality at the Pike Hill Superfund Site, Corinth, Vermont, October 2004 to December 2005
The hydrology and quality of surface water in and around the Pike Hill Brook watershed, in Corinth, Vermont, was studied from October 2004 to December 2005 by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency (USEPA). Pike Hill was mined intermittently for copper from 1847 to 1919 and the site is known to be contributing trace elements and acidity to Pike Hill
Authors
Richard G. Kiah, Jeffrey R. Deacon, Nadine M. Piatak, Robert R. Seal, James F. Coles, Jane M. Hammarstrom
Geochemical and mineralogical characterization of the abandoned Valzinco (lead-zinc) and Mitchell (gold) mine sites prior to reclamation, Spotsylvania County, Virginia
The Virginia gold-pyrite belt, part of the central Virginia volcanic-plutonic belt, hosts numerous abandoned metal mines. The belt extends from about 50 km south of Washington, D.C., for approximately 175 km to the southwest into central Virginia. The rocks that comprise the belt include metamorphosed volcanic and clastic (noncarbonate) sedimentary rocks that were originally deposited during the O
Authors
Jane M. Hammarstrom, Adam N. Johnson, Robert R. Seal, Allen L. Meier, Paul L. Briggs, Nadine M. Piatak
Geochemical Characterization of Mine Waste, Mine Drainage, and Stream Sediments at the Pike Hill Copper Mine Superfund Site, Orange County, Vermont
The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial investigati
Authors
Nadine M. Piatak, Robert R. Seal, Jane M. Hammarstrom, Richard G. Kiah, Jeffrey R. Deacon, Monique Adams, Michael W. Anthony, Paul H. Briggs, John C. Jackson