Science and Products
A Shallow to Deep View Inside the Hydrothermally Altered and Mineralized Silverton Caldera Complex: New Geologic Insights Gained From Modern Geophysical Interpretations
The Silverton caldera complex in southwest Colorado hosts base and precious metals that have been mined since the late 1800s. Extensive mine workings, excellent bedrock exposures, and deeply incised drainages make this area a natural laboratory ideally suited for furthering our understanding of the mineral systems in a volcanic environment. In addition, state-of-the-art geophysical data processing...
Nonmetallic Industrial Mineral Resources of the U.S.
In 2012, this project initiated a multi-year effort to characterize domestic nonmetallic industrial mineral resources that are important for national infrastructure, agriculture, and energy development. Activities included (1) a national-scale compilation of production data, providing a snapshot of the nonmetallic industrial mineral deposits that were of significance through the 20th century and...
Airborne electromagnetic and magnetic survey data, Silverton, Colorado, 2019
Airborne electromagnetic (AEM) and magnetic survey data were collected during April and May 2019 along 1,467 line-kilometers in the San Juan-Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field. Data were acquired by Geotech, Ltd. with the versatile time-domain electromagnetic (VTEM-ET) system together with a Geometrics optically pumped cesium vapor magnetometer. The
Magnetic susceptibility measurements on hydrothermally altered rocks in the Silverton caldera, southwest Colorado
The U.S. Geological Survey (USGS) collected magnetic susceptibility measurements on rock outcrops to help understand causative sources of magnetic survey anomalies in the Silverton caldera region, southwest Colorado. A total of 1,400 measurements of magnetic susceptibility from 87 locations have been conducted on Paleogene volcanic and plutonic rocks that have been hydrothermally altered. Magnetic
Magnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2018
This data release includes magnetotelluric (MT) sounding data collected in July 2018 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and audiomagnetotellurics, the USGS collected MT data at 22 sites along four profiles ranging from 3 to 6 kilo
Audiomagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2019
This dataset includes audiomagnetotelluric (AMT) sounding data collected in July 2019 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and magnetotellurics, the USGS collected AMT data at 26 sites along five profiles ranging from 2 to 5 kilomet
Magnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2019
This dataset includes magnetotelluric (MT) sounding data collected in July 2019 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and audiomagnetotellurics, the USGS collected MT data at 24 sites along five profiles ranging from 2 to 5 kilometer
Airborne electromagnetic and magnetic survey data of the San Juan-Silverton Caldera complex, Silverton, Colorado, 2019
Airborne electromagnetic (AEM) and magnetic survey data were collected during April and May 2019 along 1,467 line-kilometers in the San Juan-Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field. Data were acquired by Geotech, Ltd. with the versatile time-domain electromagnetic (VTEM) system together with a Geometrics optically pumped cesium vapor magnetometer. The sur
High resolution helicopter-borne magnetic and electromagnetic survey Eureka Graben area, Colorado September 1999
On September 25, 1998, SIAL Gosciences Inc. (SIAL) was awarded Department of Interior, contract 98CRCN1018, by the U.S. Geological Survey. This contract required SIAL to carry out a high-sensitivity magnetic and electromagnetic helicopter survey over one block located in the Eureka Graben Area near Silverton, Colorado. The primary goal of this project was to provide digitally recorded and processe
Data Supporting The Geochemical Atlas of Alaska, 2016
A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska, and there are significant opportunities for applying this information. To maximize the spatial density and extent of data coverage for statewide mapping of element distributions, we compiled and integrated analyses of more than 175,000 sediment and soil samples from three major,
separate sources:
Filter Total Items: 18
Alteration Map Showing Major Faults and Veins and Associated Water-Quality Signatures of the Animas River Watershed Headwaters Near Silverton, Southwest Colorado
This map was produced to provide hard-copy and digital data for alteration assemblages in the historical mining area centered on the Tertiary San Juan and Silverton calderas. The data have direct application to geoenvironmental and mineral exploration objectives.
This dataset represents alteration mapping for the upper Animas River watershed near Silverton, Colorado. The map is based on detaile
Ferricrete, manganocrete, and bog iron occurrences with selected sedge bogs and active iron bogs and springs in the upper Animas River watershed, San Juan County, Colorado
During 1996 to 2000, the Bureau of Land Management, National
Park Service, Environmental Protection Agency, United States
Department of Agriculture (USDA) Forest Service, and the
U.S. Geological Survey (USGS) developed a coordinated
strategy to (1) study the environmental effects of
historical mining on Federal lands, and (2) remediate
contaminated s
Filter Total Items: 34
Geophysical data provide three dimensional insights into porphyry copper systems in the Silverton caldera, Colorado, USA
The Silverton caldera in southwest Colorado, USA hosts polymetallic veins and pervasively altered rocks indicative of porphyry copper systems. Nearly a kilometer of erosion has exposed multiple levels of the hydrothermal systems from shallow lithocaps down to quartz-sericite-pyrite veins. New airborne electromagnetic and magnetic survey data are integrated with previous alteration mapping and porp
Authors
Eric D. Anderson, Douglas Yager, Maria Deszcz-Pan, Bennett Eugene Hoogenboom, Brian D. Rodriguez, Bruce Smith
A novel method for conducting a geoenvironmental assessment of undiscovered ISR-amenable uranium Resources: Proof-of-concept in the Texas Coastal Plain
A geoenvironmental assessment methodology was developed to estimate waste quantities and disturbances that could be associated with the extraction of undiscovered uranium resources and identify areas on the landscape where uranium and other constituents of potential concern (COPCs) that may co-occur with uranium deposits in this region are likely to persist, if introduced into the environment. Pri
Authors
Tanya J. Gallegos, Victoria G. Stengel, Katherine Walton-Day, Johanna Blake, Andrew Teeple, Delbert G Humberson, Steven Cahan, Douglas Yager, Kent D Becher
Geological and geophysical data for a three-dimensional view—Inside the San Juan and Silverton Calderas, Southern Rocky Mountains Volcanic Field, Silverton, Colorado
IntroductionThe San Juan-Silverton caldera complex located near Silverton, Colorado, in the Southern Rocky Mountains volcanic field is an ideal natural laboratory for furthering the understanding of shallow-to-deep volcanic-related mineral systems. Recent advances in geophysical data processing and three-dimensional (3D) model construction will help to characterize shallow properties important for
Authors
Douglas B. Yager, Eric D. Anderson, Maria Deszcz-Pan, Brian D. Rodriguez, Bruce D. Smith
Potash—A vital agricultural nutrient sourced from geologic deposits
This report summarizes the primary sources of potash in the United States. Potash is an essential nutrient that, along with phosphorus and nitrogen, is used as fertilizer for growing crops. Plants require sufficient potash to activate enzymes, which in turn catalyze chemical reactions important for water uptake and photosynthesis. When potassium is available in quantities necessary for healthy pla
Authors
Douglas B. Yager
Geology and mineral resources of the Sheldon-Hart Mountain National Wildlife Refuge Complex (Oregon and Nevada), the Southeastern Oregon and North-Central Nevada, and the Southern Idaho and Northern Nevada (and Utah) Sagebrush Focal Areas: Chapter B in
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpo
Authors
Peter G. Vikre, Mary Ellen Benson, Donald I. Bleiwas, Joseph Colgan, Pamela M. Cossette, Jacob DeAngelo, Connie L. Dicken, Ronald M. Drake, Edward A. du Bray, Gregory L. Fernette, Jonathan M. G. Glen, Jon E. Haacke, Susan M. Hall, Albert H. Hofstra, David A. John, Stephen Ludington, Mark J. Mihalasky, James J. Rytuba, Brian N. Shaffer, Lisa L. Stillings, John C. Wallis, Colin F. Williams, Douglas B. Yager, Lukas Zürcher
Geology and mineral resources of the North-Central Montana Sagebrush Focal Area: Chapter D in Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpo
Authors
Jeffrey L. Mauk, Michael L. Zientek, B. Carter Hearn, Heather L. Parks, M. Christopher Jenkins, Eric D. Anderson, Mary Ellen Benson, Donald I. Bleiwas, Jacob DeAngelo, Paul Denning, Connie L. Dicken, Ronald M. Drake, Gregory L. Fernette, Helen W. Folger, Stuart A. Giles, Jonathan M. G. Glen, Matthew Granitto, Jon E. Haacke, John D. Horton, Karen D. Kelley, Joyce A. Ober, Barnaby W. Rockwell, Carma A. San Juan, Elizabeth S. Sangine, Peter N. Schweitzer, Brian N. Shaffer, Steven M. Smith, Colin F. Williams, Douglas B. Yager
By
Energy and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geology, Energy & Minerals Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center, National Minerals Information Center
Geology and mineral resources of the Southwestern and South-Central Wyoming Sagebrush Focal Area, Wyoming, and the Bear River Watershed Sagebrush Focal Area, Wyoming and Utah: Chapter E in Mineral resources of the Sagebrush Focal Areas of Idaho, Monta
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpo
Authors
Anna B. Wilson, Timothy S. Hayes, Mary Ellen Benson, Douglas B. Yager, Eric D. Anderson, Donald I. Bleiwas, Jacob DeAngelo, Connie L. Dicken, Ronald M. Drake, Gregory L. Fernette, Stuart A. Giles, Jonathan M. G. Glen, Jon E. Haacke, John D. Horton, Heather L. Parks, Barnaby W. Rockwell, Colin F. Williams
Use of mineral/solution equilibrium calculations to assess the potential for carnotite precipitation from groundwater in the Texas Panhandle, USA
This study investigated the potential for the uranium mineral carnotite (K2(UO2)2(VO4)2·3H2O) to precipitate from evaporating groundwater in the Texas Panhandle region of the United States. The evolution of groundwater chemistry during evaporation was modeled with the USGS geochemical code PHREEQC using water-quality data from 100 groundwater wells downloaded from the USGS National Water Informati
Authors
Anthony J. Ranalli, Douglas B. Yager
The geochemical atlas of Alaska, 2016
A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density and extent of data coverage for statewide mapping of
Authors
Gregory K. Lee, Douglas B. Yager, Jeffrey L. Mauk, Matthew Granitto, Paul Denning, Bronwen Wang, Melanie B. Werdon
New perspectives on a 140-year legacy of mining and abandoned mine cleanup in the San Juan Mountains, Colorado
The Gold King mine water release that occurred on 5 August 2015 near the historical mining community of Silverton, Colorado, highlights the environmental legacy that abandoned mines have on the environment. During reclamation efforts, a breach of collapsed workings at the Gold King mine sent 3 million gallons of acidic and metal-rich mine water into the upper Animas River, a tributary to the Color
Authors
Douglas B. Yager, David L. Fey, Thomas Chapin, Raymond H. Johnson
GIS-Based Identification of Areas with Mineral Resource Potential for Six Selected Deposit Groups, Bureau of Land Management Central Yukon Planning Area, Alaska
This study, covering the Bureau of Land Management (BLM) Central Yukon Planning Area (CYPA), Alaska, was prepared to aid BLM mineral resource management planning. Estimated mineral resource potential and certainty are mapped for six selected mineral deposit groups: (1) rare earth element (REE) deposits associated with peralkaline to carbonatitic intrusive igneous rocks, (2) placer and paleoplacer
Authors
James V. Jones, Susan M. Karl, Keith A. Labay, Nora B. Shew, Matthew Granitto, Timothy S. Hayes, Jeffrey L. Mauk, Jeanine M. Schmidt, Erin Todd, Bronwen Wang, Melanie B. Werdon, Douglas B. Yager
A GIS and statistical approach to identify variables that control water quality in hydrothermally altered and mineralized watersheds, Silverton, Colorado, USA
Hydrothermally altered bedrock in the Silverton mining area, southwest Colorado, USA, contains sulfide minerals that weather to produce acidic and metal-rich leachate that is toxic to aquatic life. This study utilized a geographic information system (GIS) and statistical approach to identify watershed-scale geologic variables in the Silverton area that influence water quality. GIS analysis of mine
Authors
Douglas B. Yager, Raymond H. Johnson, Barnaby W. Rockwell, Jonathan S. Caine, Kathleen S. Smith
Science and Products
- Science
A Shallow to Deep View Inside the Hydrothermally Altered and Mineralized Silverton Caldera Complex: New Geologic Insights Gained From Modern Geophysical Interpretations
The Silverton caldera complex in southwest Colorado hosts base and precious metals that have been mined since the late 1800s. Extensive mine workings, excellent bedrock exposures, and deeply incised drainages make this area a natural laboratory ideally suited for furthering our understanding of the mineral systems in a volcanic environment. In addition, state-of-the-art geophysical data processing...Nonmetallic Industrial Mineral Resources of the U.S.
In 2012, this project initiated a multi-year effort to characterize domestic nonmetallic industrial mineral resources that are important for national infrastructure, agriculture, and energy development. Activities included (1) a national-scale compilation of production data, providing a snapshot of the nonmetallic industrial mineral deposits that were of significance through the 20th century and... - Data
Airborne electromagnetic and magnetic survey data, Silverton, Colorado, 2019
Airborne electromagnetic (AEM) and magnetic survey data were collected during April and May 2019 along 1,467 line-kilometers in the San Juan-Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field. Data were acquired by Geotech, Ltd. with the versatile time-domain electromagnetic (VTEM-ET) system together with a Geometrics optically pumped cesium vapor magnetometer. TheMagnetic susceptibility measurements on hydrothermally altered rocks in the Silverton caldera, southwest Colorado
The U.S. Geological Survey (USGS) collected magnetic susceptibility measurements on rock outcrops to help understand causative sources of magnetic survey anomalies in the Silverton caldera region, southwest Colorado. A total of 1,400 measurements of magnetic susceptibility from 87 locations have been conducted on Paleogene volcanic and plutonic rocks that have been hydrothermally altered. MagneticMagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2018
This data release includes magnetotelluric (MT) sounding data collected in July 2018 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and audiomagnetotellurics, the USGS collected MT data at 22 sites along four profiles ranging from 3 to 6 kiloAudiomagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2019
This dataset includes audiomagnetotelluric (AMT) sounding data collected in July 2019 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and magnetotellurics, the USGS collected AMT data at 26 sites along five profiles ranging from 2 to 5 kilometMagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2019
This dataset includes magnetotelluric (MT) sounding data collected in July 2019 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and audiomagnetotellurics, the USGS collected MT data at 24 sites along five profiles ranging from 2 to 5 kilometerAirborne electromagnetic and magnetic survey data of the San Juan-Silverton Caldera complex, Silverton, Colorado, 2019
Airborne electromagnetic (AEM) and magnetic survey data were collected during April and May 2019 along 1,467 line-kilometers in the San Juan-Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field. Data were acquired by Geotech, Ltd. with the versatile time-domain electromagnetic (VTEM) system together with a Geometrics optically pumped cesium vapor magnetometer. The surHigh resolution helicopter-borne magnetic and electromagnetic survey Eureka Graben area, Colorado September 1999
On September 25, 1998, SIAL Gosciences Inc. (SIAL) was awarded Department of Interior, contract 98CRCN1018, by the U.S. Geological Survey. This contract required SIAL to carry out a high-sensitivity magnetic and electromagnetic helicopter survey over one block located in the Eureka Graben Area near Silverton, Colorado. The primary goal of this project was to provide digitally recorded and processeData Supporting The Geochemical Atlas of Alaska, 2016
A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska, and there are significant opportunities for applying this information. To maximize the spatial density and extent of data coverage for statewide mapping of element distributions, we compiled and integrated analyses of more than 175,000 sediment and soil samples from three major, separate sources: - Maps
Filter Total Items: 18
Alteration Map Showing Major Faults and Veins and Associated Water-Quality Signatures of the Animas River Watershed Headwaters Near Silverton, Southwest Colorado
This map was produced to provide hard-copy and digital data for alteration assemblages in the historical mining area centered on the Tertiary San Juan and Silverton calderas. The data have direct application to geoenvironmental and mineral exploration objectives. This dataset represents alteration mapping for the upper Animas River watershed near Silverton, Colorado. The map is based on detaileFerricrete, manganocrete, and bog iron occurrences with selected sedge bogs and active iron bogs and springs in the upper Animas River watershed, San Juan County, Colorado
During 1996 to 2000, the Bureau of Land Management, National Park Service, Environmental Protection Agency, United States Department of Agriculture (USDA) Forest Service, and the U.S. Geological Survey (USGS) developed a coordinated strategy to (1) study the environmental effects of historical mining on Federal lands, and (2) remediate contaminated s - Multimedia
- Publications
Filter Total Items: 34
Geophysical data provide three dimensional insights into porphyry copper systems in the Silverton caldera, Colorado, USA
The Silverton caldera in southwest Colorado, USA hosts polymetallic veins and pervasively altered rocks indicative of porphyry copper systems. Nearly a kilometer of erosion has exposed multiple levels of the hydrothermal systems from shallow lithocaps down to quartz-sericite-pyrite veins. New airborne electromagnetic and magnetic survey data are integrated with previous alteration mapping and porpAuthorsEric D. Anderson, Douglas Yager, Maria Deszcz-Pan, Bennett Eugene Hoogenboom, Brian D. Rodriguez, Bruce SmithA novel method for conducting a geoenvironmental assessment of undiscovered ISR-amenable uranium Resources: Proof-of-concept in the Texas Coastal Plain
A geoenvironmental assessment methodology was developed to estimate waste quantities and disturbances that could be associated with the extraction of undiscovered uranium resources and identify areas on the landscape where uranium and other constituents of potential concern (COPCs) that may co-occur with uranium deposits in this region are likely to persist, if introduced into the environment. PriAuthorsTanya J. Gallegos, Victoria G. Stengel, Katherine Walton-Day, Johanna Blake, Andrew Teeple, Delbert G Humberson, Steven Cahan, Douglas Yager, Kent D BecherGeological and geophysical data for a three-dimensional view—Inside the San Juan and Silverton Calderas, Southern Rocky Mountains Volcanic Field, Silverton, Colorado
IntroductionThe San Juan-Silverton caldera complex located near Silverton, Colorado, in the Southern Rocky Mountains volcanic field is an ideal natural laboratory for furthering the understanding of shallow-to-deep volcanic-related mineral systems. Recent advances in geophysical data processing and three-dimensional (3D) model construction will help to characterize shallow properties important forAuthorsDouglas B. Yager, Eric D. Anderson, Maria Deszcz-Pan, Brian D. Rodriguez, Bruce D. SmithPotash—A vital agricultural nutrient sourced from geologic deposits
This report summarizes the primary sources of potash in the United States. Potash is an essential nutrient that, along with phosphorus and nitrogen, is used as fertilizer for growing crops. Plants require sufficient potash to activate enzymes, which in turn catalyze chemical reactions important for water uptake and photosynthesis. When potassium is available in quantities necessary for healthy plaAuthorsDouglas B. YagerGeology and mineral resources of the Sheldon-Hart Mountain National Wildlife Refuge Complex (Oregon and Nevada), the Southeastern Oregon and North-Central Nevada, and the Southern Idaho and Northern Nevada (and Utah) Sagebrush Focal Areas: Chapter B in
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpoAuthorsPeter G. Vikre, Mary Ellen Benson, Donald I. Bleiwas, Joseph Colgan, Pamela M. Cossette, Jacob DeAngelo, Connie L. Dicken, Ronald M. Drake, Edward A. du Bray, Gregory L. Fernette, Jonathan M. G. Glen, Jon E. Haacke, Susan M. Hall, Albert H. Hofstra, David A. John, Stephen Ludington, Mark J. Mihalasky, James J. Rytuba, Brian N. Shaffer, Lisa L. Stillings, John C. Wallis, Colin F. Williams, Douglas B. Yager, Lukas ZürcherGeology and mineral resources of the North-Central Montana Sagebrush Focal Area: Chapter D in Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpoAuthorsJeffrey L. Mauk, Michael L. Zientek, B. Carter Hearn, Heather L. Parks, M. Christopher Jenkins, Eric D. Anderson, Mary Ellen Benson, Donald I. Bleiwas, Jacob DeAngelo, Paul Denning, Connie L. Dicken, Ronald M. Drake, Gregory L. Fernette, Helen W. Folger, Stuart A. Giles, Jonathan M. G. Glen, Matthew Granitto, Jon E. Haacke, John D. Horton, Karen D. Kelley, Joyce A. Ober, Barnaby W. Rockwell, Carma A. San Juan, Elizabeth S. Sangine, Peter N. Schweitzer, Brian N. Shaffer, Steven M. Smith, Colin F. Williams, Douglas B. YagerByEnergy and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geology, Energy & Minerals Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center, National Minerals Information CenterGeology and mineral resources of the Southwestern and South-Central Wyoming Sagebrush Focal Area, Wyoming, and the Bear River Watershed Sagebrush Focal Area, Wyoming and Utah: Chapter E in Mineral resources of the Sagebrush Focal Areas of Idaho, Monta
SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpoAuthorsAnna B. Wilson, Timothy S. Hayes, Mary Ellen Benson, Douglas B. Yager, Eric D. Anderson, Donald I. Bleiwas, Jacob DeAngelo, Connie L. Dicken, Ronald M. Drake, Gregory L. Fernette, Stuart A. Giles, Jonathan M. G. Glen, Jon E. Haacke, John D. Horton, Heather L. Parks, Barnaby W. Rockwell, Colin F. WilliamsUse of mineral/solution equilibrium calculations to assess the potential for carnotite precipitation from groundwater in the Texas Panhandle, USA
This study investigated the potential for the uranium mineral carnotite (K2(UO2)2(VO4)2·3H2O) to precipitate from evaporating groundwater in the Texas Panhandle region of the United States. The evolution of groundwater chemistry during evaporation was modeled with the USGS geochemical code PHREEQC using water-quality data from 100 groundwater wells downloaded from the USGS National Water InformatiAuthorsAnthony J. Ranalli, Douglas B. YagerThe geochemical atlas of Alaska, 2016
A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density and extent of data coverage for statewide mapping ofAuthorsGregory K. Lee, Douglas B. Yager, Jeffrey L. Mauk, Matthew Granitto, Paul Denning, Bronwen Wang, Melanie B. WerdonNew perspectives on a 140-year legacy of mining and abandoned mine cleanup in the San Juan Mountains, Colorado
The Gold King mine water release that occurred on 5 August 2015 near the historical mining community of Silverton, Colorado, highlights the environmental legacy that abandoned mines have on the environment. During reclamation efforts, a breach of collapsed workings at the Gold King mine sent 3 million gallons of acidic and metal-rich mine water into the upper Animas River, a tributary to the ColorAuthorsDouglas B. Yager, David L. Fey, Thomas Chapin, Raymond H. JohnsonGIS-Based Identification of Areas with Mineral Resource Potential for Six Selected Deposit Groups, Bureau of Land Management Central Yukon Planning Area, Alaska
This study, covering the Bureau of Land Management (BLM) Central Yukon Planning Area (CYPA), Alaska, was prepared to aid BLM mineral resource management planning. Estimated mineral resource potential and certainty are mapped for six selected mineral deposit groups: (1) rare earth element (REE) deposits associated with peralkaline to carbonatitic intrusive igneous rocks, (2) placer and paleoplacerAuthorsJames V. Jones, Susan M. Karl, Keith A. Labay, Nora B. Shew, Matthew Granitto, Timothy S. Hayes, Jeffrey L. Mauk, Jeanine M. Schmidt, Erin Todd, Bronwen Wang, Melanie B. Werdon, Douglas B. YagerA GIS and statistical approach to identify variables that control water quality in hydrothermally altered and mineralized watersheds, Silverton, Colorado, USA
Hydrothermally altered bedrock in the Silverton mining area, southwest Colorado, USA, contains sulfide minerals that weather to produce acidic and metal-rich leachate that is toxic to aquatic life. This study utilized a geographic information system (GIS) and statistical approach to identify watershed-scale geologic variables in the Silverton area that influence water quality. GIS analysis of mineAuthorsDouglas B. Yager, Raymond H. Johnson, Barnaby W. Rockwell, Jonathan S. Caine, Kathleen S. Smith - News