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Floyd Gray (Former Employee)

Science and Products

Image shows orange, discolored water in a small canyon

USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS is conducting sampling, monitoring, and modeling in the Patagonia Mountains and nearby regions in Arizona to identify contaminant risk potential of legacy and proposed mine sites and to develop classification criteria for predicting vulnerabilities and targeted sources and sinks of metal contaminants.
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center
USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS is conducting sampling, monitoring, and modeling in the Patagonia Mountains and nearby regions in Arizona to identify contaminant risk potential of legacy and proposed mine sites and to develop classification criteria for predicting vulnerabilities and targeted sources and sinks of metal contaminants.
Learn More
Landsat image of Puerto Rico and Virgin Islands

Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Project objectives are to develop a modern probabilistic quantitative mineral resource assessment of Puerto Rico, U.S. Virgin Islands and adjacent geologically similar areas that examines the potential for minerals-based economic development and trade within the region.
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center
Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Project objectives are to develop a modern probabilistic quantitative mineral resource assessment of Puerto Rico, U.S. Virgin Islands and adjacent geologically similar areas that examines the potential for minerals-based economic development and trade within the region.
Learn More

Database for the geologic map of the upper Santa Cruz River basin, southern Arizona Database for the geologic map of the upper Santa Cruz River basin, southern Arizona

This digital publication contains the database, base maps, and style files used to build the geologic map of the upper Santa Cruz River basin in southern Arizona published in U.S. Geological Survey Scientific Investigations Map 3490 (Page and others, 2023). Shapefiles are also included for the user’s convenience. In the database, there are polygon features outlining the map units and...
By
Geosciences and Environmental Change Science Center

Data Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program Data Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program

This is a data release of data presented in the report "Binational Study of the Transboundary San Pedro Aquifer", Callegary and others, 2016. The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the International Boundary. Both the United States and Mexico recognize that, in a region of scarce water and expanding populations, better...
By
Arizona Water Science Center

Geochemistry of Sediment and Associated Leachates from Samples near the Old Yuma Mine, AZ Geochemistry of Sediment and Associated Leachates from Samples near the Old Yuma Mine, AZ

This data set includes analysis of 38 sediment samples collected near the Old Yuma Mine. The sediment samples were collected from tailings, waste rock, stream sediment, and background locations. All samples were analyzed by a total digestion method, some by the USEPA 3050 method, and some were leached by the USEPA 1312 method.
By
Arizona Water Science Center
Filter Total Items: 18

Geologic map and hydrogeologic investigations of the upper Santa Cruz River basin, southern Arizona Geologic map and hydrogeologic investigations of the upper Santa Cruz River basin, southern Arizona

This report includes an updated geologic map and cross sections of the upper Santa Cruz River basin, southern Arizona. The map and cross sections describe the geometry, thickness, and structure of the Miocene to Holocene units which form the main aquifers in the basin. The report also includes results of new hydrogeologic studies including (1) mapping and defining depth to bedrock based...
By
Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center

Geologic map of the Rio Rico and Nogales 7.5’ quadrangles, Santa Cruz County, Arizona Geologic map of the Rio Rico and Nogales 7.5’ quadrangles, Santa Cruz County, Arizona

The Rio Rico and Nogales (Arizona) 1:24,000-scale quadrangles are located in the Basin and Range Province of southern Arizona, and the southern edge of the map is the international border with Sonora, Mexico. The major urban area is Nogales, a bi-national city known as “the gateway to Mexico.” Rocks exposed in the map area range in age from Jurassic through Quaternary. Major...
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

Geologic map of the San Carlos Indian Reservation, Arizona Geologic map of the San Carlos Indian Reservation, Arizona

No abstract available.

Geologic map of the Venezuela part of the Piedra de Cocuy 2 degrees x 3 degrees Quadrangle, Amazonas Federal Territory, Venezuela Geologic map of the Venezuela part of the Piedra de Cocuy 2 degrees x 3 degrees Quadrangle, Amazonas Federal Territory, Venezuela

No abstract available.

Geologic map of the Guri and southern part of the Tucupita 2 degrees by 3 degrees quadrangles, Bolivar State, Venezuela Geologic map of the Guri and southern part of the Tucupita 2 degrees by 3 degrees quadrangles, Bolivar State, Venezuela

No abstract available.

Mineral resource assessment of the Ajo and Lukeville 1 degree by 2 degrees quadrangles, Arizona Mineral resource assessment of the Ajo and Lukeville 1 degree by 2 degrees quadrangles, Arizona

No abstract available.
Filter Total Items: 58

“Leaky weirs” capture alluvial deposition and enhance seasonal mountain-front recharge in dryland streams “Leaky weirs” capture alluvial deposition and enhance seasonal mountain-front recharge in dryland streams

“Leaky weirs” are rock structures installed in dryland streams, which are anchored into exposed bedrock, loosely cemented, and designed to allow water to slowly pass through. They are being tested at a ranch in southeastern Arizona, USA, to restore and conserve the historic range and desert wetlands. Data are collected to assess how leaky weirs impact surface water, subsurface water, and
Authors
Laura M. Norman, Kristine; Uhlman, Hanna Coy, Natalie R. Wilson, Andrew M. Bennett, Floyd Gray, Kurt T. Ehrenberg
By
Western Geographic Science Center

Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona

No abstract available.
Authors
Lisa A. Thompson, Gordon B. Haxel, Donald W. Peterson, Daniel J. May, Richard M. Tosdal, Robert J. Miller, Floyd Gray, Richard A. LeVeque, Paul J. Umhoefer
By
Geology, Minerals, Energy, and Geophysics Science Center

Microbial endophytes and compost improve plant growth in two contrasting types of hard rock mining waste Microbial endophytes and compost improve plant growth in two contrasting types of hard rock mining waste

The re-vegetation of mining wastes with native plants is a comparatively low-cost solution for mine reclamation. However, re-vegetation fails when extreme pH values, low organic matter, or high concentrations of phytotoxic elements inhibit plant establishment and growth. Our aim was to determine whether the combined addition of municipal waste compost and diazotrophic endophytes (i.e
Authors
Courtney Creamer, Mary-Catherine Leewis, Francesca C. Governali, John Freeman, Floyd Gray, Emily G. Wright, Andrea L. Foster
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center

Mapa metalogenético de América Central y El Caribe Mapa metalogenético de América Central y El Caribe

La Asociación de Servicios Geológicos y Mineros de Iberoamérica (ASGMI), bajo los auspicios de la Comisión de la Carta Geológica del Mundo (CCGM) preparó la primera versión del Mapa Metalogénico de América Central y el Caribe. La coordinación general estuvo a cargo del Servicio Geológico Minero Argentino (SEGEMAR), con tres coordinaciones regionales: América Central a cargo del Servicio...
Authors
Eduardo O Zappettini, Gloria Prieto-Rincon, Natalia Amezcua, Santiago Munoz-Tapia, Janeth Sepulveda-Ospina, Carlos M. Celada-Arango, David Jara, X Cazanas-Diaz, Jorge L. Torres-Zafra, Jorge L. Cobiella-Reguera, Lukas Zurcher, Greta J. Orris, Floyd Gray, Carolina Maldonado-Diaz, Noe Rodriguez, Ramon Merida-Montiel, Carlos A. Zarruk
By
Geology, Minerals, Energy, and Geophysics Science Center

Preliminary geologic map of the Greater Antilles and the Virgin Islands Preliminary geologic map of the Greater Antilles and the Virgin Islands

Introduction This geologic map of the Greater Antilles and the Virgin Islands is a compilation of information from the literature, integrated to provide a seamless geologic map of the region. The geology shown on sheet 1 covers Cuba, the island of Hispaniola, which includes Haiti and the Dominican Republic, Jamaica, the Cayman Islands, Puerto Rico, and the U.S. and British Virgin Islands...
Authors
Frederic H. Wilson, Greta Orris, Floyd Gray
By
Geology, Energy, and Minerals Mission Area, Ecosystems Mission Area, Alaska Science Center

Probabilistic mineral resource assessment of U.S. Territories of the Caribbean Basin and adjacent areas: Progress report Probabilistic mineral resource assessment of U.S. Territories of the Caribbean Basin and adjacent areas: Progress report

The U.S. Geological Survey is partnering with the IberoAmerican Association of Geological and Mining Surveys (ASGMI) to conduct an assessment of undiscovered metallic and non-metallic resources in the Greater Antilles region. The assessment plans to provide science-based information on the geologic availability of these resources for development, land-use planning, and decision making...
Authors
Lukas Zurcher, Floyd Gray, Stephen Ludington, Frederic H. Wilson, Greta J. Orris, Mark D. Cocker, Mark E. Gettings, Timothy Hayes
By
Ecosystems Mission Area, Alaska Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Science and Products

Image shows orange, discolored water in a small canyon

USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS is conducting sampling, monitoring, and modeling in the Patagonia Mountains and nearby regions in Arizona to identify contaminant risk potential of legacy and proposed mine sites and to develop classification criteria for predicting vulnerabilities and targeted sources and sinks of metal contaminants.
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center
USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS Response to Possible Metals Contamination from Legacy Mines in the Patagonia Mountains Region and Adjacent Areas, Southeast Arizona and a Template for Future Mineral Environmental Emergency Response

USGS is conducting sampling, monitoring, and modeling in the Patagonia Mountains and nearby regions in Arizona to identify contaminant risk potential of legacy and proposed mine sites and to develop classification criteria for predicting vulnerabilities and targeted sources and sinks of metal contaminants.
Learn More
Landsat image of Puerto Rico and Virgin Islands

Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Project objectives are to develop a modern probabilistic quantitative mineral resource assessment of Puerto Rico, U.S. Virgin Islands and adjacent geologically similar areas that examines the potential for minerals-based economic development and trade within the region.
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center
Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas

Project objectives are to develop a modern probabilistic quantitative mineral resource assessment of Puerto Rico, U.S. Virgin Islands and adjacent geologically similar areas that examines the potential for minerals-based economic development and trade within the region.
Learn More

Database for the geologic map of the upper Santa Cruz River basin, southern Arizona Database for the geologic map of the upper Santa Cruz River basin, southern Arizona

This digital publication contains the database, base maps, and style files used to build the geologic map of the upper Santa Cruz River basin in southern Arizona published in U.S. Geological Survey Scientific Investigations Map 3490 (Page and others, 2023). Shapefiles are also included for the user’s convenience. In the database, there are polygon features outlining the map units and...
By
Geosciences and Environmental Change Science Center

Data Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program Data Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program

This is a data release of data presented in the report "Binational Study of the Transboundary San Pedro Aquifer", Callegary and others, 2016. The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the International Boundary. Both the United States and Mexico recognize that, in a region of scarce water and expanding populations, better...
By
Arizona Water Science Center

Geochemistry of Sediment and Associated Leachates from Samples near the Old Yuma Mine, AZ Geochemistry of Sediment and Associated Leachates from Samples near the Old Yuma Mine, AZ

This data set includes analysis of 38 sediment samples collected near the Old Yuma Mine. The sediment samples were collected from tailings, waste rock, stream sediment, and background locations. All samples were analyzed by a total digestion method, some by the USEPA 3050 method, and some were leached by the USEPA 1312 method.
By
Arizona Water Science Center
Filter Total Items: 18

Geologic map and hydrogeologic investigations of the upper Santa Cruz River basin, southern Arizona Geologic map and hydrogeologic investigations of the upper Santa Cruz River basin, southern Arizona

This report includes an updated geologic map and cross sections of the upper Santa Cruz River basin, southern Arizona. The map and cross sections describe the geometry, thickness, and structure of the Miocene to Holocene units which form the main aquifers in the basin. The report also includes results of new hydrogeologic studies including (1) mapping and defining depth to bedrock based...
By
Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center

Geologic map of the Rio Rico and Nogales 7.5’ quadrangles, Santa Cruz County, Arizona Geologic map of the Rio Rico and Nogales 7.5’ quadrangles, Santa Cruz County, Arizona

The Rio Rico and Nogales (Arizona) 1:24,000-scale quadrangles are located in the Basin and Range Province of southern Arizona, and the southern edge of the map is the international border with Sonora, Mexico. The major urban area is Nogales, a bi-national city known as “the gateway to Mexico.” Rocks exposed in the map area range in age from Jurassic through Quaternary. Major...
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

Geologic map of the San Carlos Indian Reservation, Arizona Geologic map of the San Carlos Indian Reservation, Arizona

No abstract available.

Geologic map of the Venezuela part of the Piedra de Cocuy 2 degrees x 3 degrees Quadrangle, Amazonas Federal Territory, Venezuela Geologic map of the Venezuela part of the Piedra de Cocuy 2 degrees x 3 degrees Quadrangle, Amazonas Federal Territory, Venezuela

No abstract available.

Geologic map of the Guri and southern part of the Tucupita 2 degrees by 3 degrees quadrangles, Bolivar State, Venezuela Geologic map of the Guri and southern part of the Tucupita 2 degrees by 3 degrees quadrangles, Bolivar State, Venezuela

No abstract available.

Mineral resource assessment of the Ajo and Lukeville 1 degree by 2 degrees quadrangles, Arizona Mineral resource assessment of the Ajo and Lukeville 1 degree by 2 degrees quadrangles, Arizona

No abstract available.
Filter Total Items: 58

“Leaky weirs” capture alluvial deposition and enhance seasonal mountain-front recharge in dryland streams “Leaky weirs” capture alluvial deposition and enhance seasonal mountain-front recharge in dryland streams

“Leaky weirs” are rock structures installed in dryland streams, which are anchored into exposed bedrock, loosely cemented, and designed to allow water to slowly pass through. They are being tested at a ranch in southeastern Arizona, USA, to restore and conserve the historic range and desert wetlands. Data are collected to assess how leaky weirs impact surface water, subsurface water, and
Authors
Laura M. Norman, Kristine; Uhlman, Hanna Coy, Natalie R. Wilson, Andrew M. Bennett, Floyd Gray, Kurt T. Ehrenberg
By
Western Geographic Science Center

Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona

No abstract available.
Authors
Lisa A. Thompson, Gordon B. Haxel, Donald W. Peterson, Daniel J. May, Richard M. Tosdal, Robert J. Miller, Floyd Gray, Richard A. LeVeque, Paul J. Umhoefer
By
Geology, Minerals, Energy, and Geophysics Science Center

Microbial endophytes and compost improve plant growth in two contrasting types of hard rock mining waste Microbial endophytes and compost improve plant growth in two contrasting types of hard rock mining waste

The re-vegetation of mining wastes with native plants is a comparatively low-cost solution for mine reclamation. However, re-vegetation fails when extreme pH values, low organic matter, or high concentrations of phytotoxic elements inhibit plant establishment and growth. Our aim was to determine whether the combined addition of municipal waste compost and diazotrophic endophytes (i.e
Authors
Courtney Creamer, Mary-Catherine Leewis, Francesca C. Governali, John Freeman, Floyd Gray, Emily G. Wright, Andrea L. Foster
By
Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center

Mapa metalogenético de América Central y El Caribe Mapa metalogenético de América Central y El Caribe

La Asociación de Servicios Geológicos y Mineros de Iberoamérica (ASGMI), bajo los auspicios de la Comisión de la Carta Geológica del Mundo (CCGM) preparó la primera versión del Mapa Metalogénico de América Central y el Caribe. La coordinación general estuvo a cargo del Servicio Geológico Minero Argentino (SEGEMAR), con tres coordinaciones regionales: América Central a cargo del Servicio...
Authors
Eduardo O Zappettini, Gloria Prieto-Rincon, Natalia Amezcua, Santiago Munoz-Tapia, Janeth Sepulveda-Ospina, Carlos M. Celada-Arango, David Jara, X Cazanas-Diaz, Jorge L. Torres-Zafra, Jorge L. Cobiella-Reguera, Lukas Zurcher, Greta J. Orris, Floyd Gray, Carolina Maldonado-Diaz, Noe Rodriguez, Ramon Merida-Montiel, Carlos A. Zarruk
By
Geology, Minerals, Energy, and Geophysics Science Center

Preliminary geologic map of the Greater Antilles and the Virgin Islands Preliminary geologic map of the Greater Antilles and the Virgin Islands

Introduction This geologic map of the Greater Antilles and the Virgin Islands is a compilation of information from the literature, integrated to provide a seamless geologic map of the region. The geology shown on sheet 1 covers Cuba, the island of Hispaniola, which includes Haiti and the Dominican Republic, Jamaica, the Cayman Islands, Puerto Rico, and the U.S. and British Virgin Islands...
Authors
Frederic H. Wilson, Greta Orris, Floyd Gray
By
Geology, Energy, and Minerals Mission Area, Ecosystems Mission Area, Alaska Science Center

Probabilistic mineral resource assessment of U.S. Territories of the Caribbean Basin and adjacent areas: Progress report Probabilistic mineral resource assessment of U.S. Territories of the Caribbean Basin and adjacent areas: Progress report

The U.S. Geological Survey is partnering with the IberoAmerican Association of Geological and Mining Surveys (ASGMI) to conduct an assessment of undiscovered metallic and non-metallic resources in the Greater Antilles region. The assessment plans to provide science-based information on the geologic availability of these resources for development, land-use planning, and decision making...
Authors
Lukas Zurcher, Floyd Gray, Stephen Ludington, Frederic H. Wilson, Greta J. Orris, Mark D. Cocker, Mark E. Gettings, Timothy Hayes
By
Ecosystems Mission Area, Alaska Science Center, Geology, Minerals, Energy, and Geophysics Science Center
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