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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.

Map showing geochemical characteristics of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine Counties, Oregon Map showing geochemical characteristics of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine Counties, Oregon

The North Fork Smith River Roadless Areas are located primarily in Del Norte County, northern California, include small parts of Curry and Josephine Counties, Oreg., and cover parts of the Gasquet, Crescent City, and Chetco Peak 15-minute quadrangles. The areas encompass aproximately 39,400 acres of Six rivers National Forest and 950 acres of Siskiyou National Forest and extend from just...

Geologic map of the Growler Mountains, Pima and Maricopa counties, Arizona Geologic map of the Growler Mountains, Pima and Maricopa counties, Arizona

No abstract available.

Maps showing geochemical characteristics of platinum-group elements and gold in rock samples from the Kalmiopsis Wilderness, Southwestern Oregon Maps showing geochemical characteristics of platinum-group elements and gold in rock samples from the Kalmiopsis Wilderness, Southwestern Oregon

No abstract available.

Geochemical map and rock and stream-sediment data from the Wild Rogue Wilderness, Coos and Curry counties, Oregon Geochemical map and rock and stream-sediment data from the Wild Rogue Wilderness, Coos and Curry counties, Oregon

The Wild Rogue Wilderness is located in Coos and Curry Counties, southwestern Oregon and covers part of the Bone Mountain, Marial, and Agness 15' quadrangles (fig. 1). It is an elongate area, 19 mi by 0.8 to 3 mi (31 km by 1.3 to 5 km) and includes approximately 35,818 acres extending from the town of Agness northeast to Mount Bolivar. The area is characterized by several diverse...

Mineral resource potential maps of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine counties, Oregon Mineral resource potential maps of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine counties, Oregon

No abstract available.

Mineral resource potential of the Wild Rogue Wilderness (NF105), Coos and Curry Counties, Oregon Mineral resource potential of the Wild Rogue Wilderness (NF105), Coos and Curry Counties, Oregon

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 Thompson, Gordon Haxel, Donald Peterson, Daniel May, Richard M. Tosdal, Robert Miller, Floyd Gray, Richard A. LeVeque, Paul 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 Governali, John Freeman, Floyd Gray, Emily Wright, Andrea 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 Celada-Arango, David Jara, X Cazanas-Diaz, Jorge Torres-Zafra, Jorge Cobiella-Reguera, Lukas Zurcher, Greta Orris, Floyd Gray, Carolina Maldonado-Diaz, Noe Rodriguez, Ramon Merida-Montiel, Carlos 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

IntroductionThis 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 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 Wilson, Greta Orris, Mark Cocker, Mark Gettings, Timothy Hayes
By
Ecosystems Mission Area, Alaska Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Geologic framework and hydrogeology of the Rio Rico and Nogales 7.5’ quadrangles, upper Santa Cruz Basin, Arizona, with three-dimensional hydrogeologic model Geologic framework and hydrogeology of the Rio Rico and Nogales 7.5’ quadrangles, upper Santa Cruz Basin, Arizona, with three-dimensional hydrogeologic model

Rapid population growth and declining annual recharge to aquifers in the upper Santa Cruz Basin area of southern Arizona, have increased the demand for additional groundwater resources. This demand is predicted to escalate in the future because of higher temperatures, longer droughts, less aquifer recharge, and decreased river and stream base flow. We conducted geologic studies to help...
Authors
William Page, Mark Bultman, D. Paco VanSistine, Christopher Menges, Floyd Gray, Michael Pantea
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

Assessment of geochemical and hydrologic conditions near Old Yuma Mine in Saguaro National Park, Arizona, 2014–17 Assessment of geochemical and hydrologic conditions near Old Yuma Mine in Saguaro National Park, Arizona, 2014–17

The Old Yuma Mine is an abandoned copper, lead, zinc, silver, and gold mine located within the boundaries of Saguaro National Park, Tucson Mountain District, Arizona. This study analyzed the geochemistry of sediments associated with the Old Yuma Mine and assessed hydrologic and geochemical conditions of groundwater to evaluate the area surrounding the Old Yuma Mine. The purpose of the...
Authors
Kimberly Beisner, Floyd Gray
By
Water Resources Mission Area, Arizona Water Science Center

Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba

The U.S. Geological Survey’s “three-step” form of mineral-resource assessment was used to obtain a preliminary estimate of copper resources in undiscovered porphyry deposits of the Paleogene Sierra Maestra Arc. Results of this preliminary assessment suggest that a mean of 3.2 undiscovered deposits are likely present. This estimate is comparable to results from an independently-derived...
Authors
Lukas Zurcher, Floyd Gray, Timothy Hayes, Greta Orris, Mark Gettings, Mark Cocker, Leila Gass
By
Geology, Minerals, Energy, and Geophysics Science Center

Hydrogeologic investigations of the Miocene Nogales Formation in the Nogales Area, Upper Santa Cruz Basin, Arizona Hydrogeologic investigations of the Miocene Nogales Formation in the Nogales Area, Upper Santa Cruz Basin, Arizona

Hydrogeologic investigations were conducted to evaluate the groundwater resource potential for the Miocene Nogales Formation in the Nogales area, southern Arizona. Results indicate that parts of the formation may provide new, deeper sources of groundwater for the area. Geologic mapping determined the hydrogeologic framework of the formation by defining lithologic, mineralogic, and...
Authors
William Page, Floyd Gray, Mark Bultman, Christopher Menges
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

San Pedro River Aquifer Binational Report San Pedro River Aquifer Binational Report

The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the international boundary. Both countries recognize that, in a region of scarce water resources and expanding populations, a greater scientific understanding of these aquifer systems would be beneficial. In light of this, the Mexican and U.S. Principal Engineers of the International...
Authors
James Callegary, Ismael Minjarez Sosa, Elia Tapia Villasenor, Placido dos Santos, Rogelio Monreal Saavedra, Franciso Javier Grijalva Noriega, A. Huth, Floyd Gray, C. Scott, Sharon Megdal, L. Oroz Ramos, Miguel Rangel Medina, James Leenhouts
By
Water Resources Mission Area, Arizona Water Science Center

Hydrologic response of streams restored with check dams in the Chiricahua Mountains, Arizona Hydrologic response of streams restored with check dams in the Chiricahua Mountains, Arizona

In this study, hydrological processes are evaluated to determine impacts of stream restoration in the West Turkey Creek, Chiricahua Mountains, southeast Arizona, during a summer-monsoon season (June–October of 2013). A paired-watershed approach was used to analyze the effectiveness of check dams to mitigate high flows and impact long-term maintenance of hydrologic function. One watershed...
Authors
Laura Norman, Fletcher Brinkerhoff, Evan Gwilliam, D. Guertin, James Callegary, David Goodrich, Pamela Nagler, Floyd Gray
By
Western Geographic 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.

Map showing geochemical characteristics of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine Counties, Oregon Map showing geochemical characteristics of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine Counties, Oregon

The North Fork Smith River Roadless Areas are located primarily in Del Norte County, northern California, include small parts of Curry and Josephine Counties, Oreg., and cover parts of the Gasquet, Crescent City, and Chetco Peak 15-minute quadrangles. The areas encompass aproximately 39,400 acres of Six rivers National Forest and 950 acres of Siskiyou National Forest and extend from just...

Geologic map of the Growler Mountains, Pima and Maricopa counties, Arizona Geologic map of the Growler Mountains, Pima and Maricopa counties, Arizona

No abstract available.

Maps showing geochemical characteristics of platinum-group elements and gold in rock samples from the Kalmiopsis Wilderness, Southwestern Oregon Maps showing geochemical characteristics of platinum-group elements and gold in rock samples from the Kalmiopsis Wilderness, Southwestern Oregon

No abstract available.

Geochemical map and rock and stream-sediment data from the Wild Rogue Wilderness, Coos and Curry counties, Oregon Geochemical map and rock and stream-sediment data from the Wild Rogue Wilderness, Coos and Curry counties, Oregon

The Wild Rogue Wilderness is located in Coos and Curry Counties, southwestern Oregon and covers part of the Bone Mountain, Marial, and Agness 15' quadrangles (fig. 1). It is an elongate area, 19 mi by 0.8 to 3 mi (31 km by 1.3 to 5 km) and includes approximately 35,818 acres extending from the town of Agness northeast to Mount Bolivar. The area is characterized by several diverse...

Mineral resource potential maps of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine counties, Oregon Mineral resource potential maps of the North Fork Smith River Roadless Areas, Del Norte County, California, Curry and Josephine counties, Oregon

No abstract available.

Mineral resource potential of the Wild Rogue Wilderness (NF105), Coos and Curry Counties, Oregon Mineral resource potential of the Wild Rogue Wilderness (NF105), Coos and Curry Counties, Oregon

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 Thompson, Gordon Haxel, Donald Peterson, Daniel May, Richard M. Tosdal, Robert Miller, Floyd Gray, Richard A. LeVeque, Paul 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 Governali, John Freeman, Floyd Gray, Emily Wright, Andrea 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 Celada-Arango, David Jara, X Cazanas-Diaz, Jorge Torres-Zafra, Jorge Cobiella-Reguera, Lukas Zurcher, Greta Orris, Floyd Gray, Carolina Maldonado-Diaz, Noe Rodriguez, Ramon Merida-Montiel, Carlos 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

IntroductionThis 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 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 Wilson, Greta Orris, Mark Cocker, Mark Gettings, Timothy Hayes
By
Ecosystems Mission Area, Alaska Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Geologic framework and hydrogeology of the Rio Rico and Nogales 7.5’ quadrangles, upper Santa Cruz Basin, Arizona, with three-dimensional hydrogeologic model Geologic framework and hydrogeology of the Rio Rico and Nogales 7.5’ quadrangles, upper Santa Cruz Basin, Arizona, with three-dimensional hydrogeologic model

Rapid population growth and declining annual recharge to aquifers in the upper Santa Cruz Basin area of southern Arizona, have increased the demand for additional groundwater resources. This demand is predicted to escalate in the future because of higher temperatures, longer droughts, less aquifer recharge, and decreased river and stream base flow. We conducted geologic studies to help...
Authors
William Page, Mark Bultman, D. Paco VanSistine, Christopher Menges, Floyd Gray, Michael Pantea
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

Assessment of geochemical and hydrologic conditions near Old Yuma Mine in Saguaro National Park, Arizona, 2014–17 Assessment of geochemical and hydrologic conditions near Old Yuma Mine in Saguaro National Park, Arizona, 2014–17

The Old Yuma Mine is an abandoned copper, lead, zinc, silver, and gold mine located within the boundaries of Saguaro National Park, Tucson Mountain District, Arizona. This study analyzed the geochemistry of sediments associated with the Old Yuma Mine and assessed hydrologic and geochemical conditions of groundwater to evaluate the area surrounding the Old Yuma Mine. The purpose of the...
Authors
Kimberly Beisner, Floyd Gray
By
Water Resources Mission Area, Arizona Water Science Center

Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba

The U.S. Geological Survey’s “three-step” form of mineral-resource assessment was used to obtain a preliminary estimate of copper resources in undiscovered porphyry deposits of the Paleogene Sierra Maestra Arc. Results of this preliminary assessment suggest that a mean of 3.2 undiscovered deposits are likely present. This estimate is comparable to results from an independently-derived...
Authors
Lukas Zurcher, Floyd Gray, Timothy Hayes, Greta Orris, Mark Gettings, Mark Cocker, Leila Gass
By
Geology, Minerals, Energy, and Geophysics Science Center

Hydrogeologic investigations of the Miocene Nogales Formation in the Nogales Area, Upper Santa Cruz Basin, Arizona Hydrogeologic investigations of the Miocene Nogales Formation in the Nogales Area, Upper Santa Cruz Basin, Arizona

Hydrogeologic investigations were conducted to evaluate the groundwater resource potential for the Miocene Nogales Formation in the Nogales area, southern Arizona. Results indicate that parts of the formation may provide new, deeper sources of groundwater for the area. Geologic mapping determined the hydrogeologic framework of the formation by defining lithologic, mineralogic, and...
Authors
William Page, Floyd Gray, Mark Bultman, Christopher Menges
By
Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

San Pedro River Aquifer Binational Report San Pedro River Aquifer Binational Report

The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the international boundary. Both countries recognize that, in a region of scarce water resources and expanding populations, a greater scientific understanding of these aquifer systems would be beneficial. In light of this, the Mexican and U.S. Principal Engineers of the International...
Authors
James Callegary, Ismael Minjarez Sosa, Elia Tapia Villasenor, Placido dos Santos, Rogelio Monreal Saavedra, Franciso Javier Grijalva Noriega, A. Huth, Floyd Gray, C. Scott, Sharon Megdal, L. Oroz Ramos, Miguel Rangel Medina, James Leenhouts
By
Water Resources Mission Area, Arizona Water Science Center

Hydrologic response of streams restored with check dams in the Chiricahua Mountains, Arizona Hydrologic response of streams restored with check dams in the Chiricahua Mountains, Arizona

In this study, hydrological processes are evaluated to determine impacts of stream restoration in the West Turkey Creek, Chiricahua Mountains, southeast Arizona, during a summer-monsoon season (June–October of 2013). A paired-watershed approach was used to analyze the effectiveness of check dams to mitigate high flows and impact long-term maintenance of hydrologic function. One watershed...
Authors
Laura Norman, Fletcher Brinkerhoff, Evan Gwilliam, D. Guertin, James Callegary, David Goodrich, Pamela Nagler, Floyd Gray
By
Western Geographic Science Center
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