Laurel G. Woodruff
Laurel Woodruff is a Scientist Emeritus with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.
Science and Products
Geochemical characterization of solid media from three watersheds that transect the basal contact of the Duluth Complex, northeastern Minnesota Geochemical characterization of solid media from three watersheds that transect the basal contact of the Duluth Complex, northeastern Minnesota
To document regional water quality in areas of potential base-metal mining, bedrock, soil, streambed sediment, and surface-water samples were collected and analyzed in three watersheds that cross the basal part of the Duluth Complex (northeastern Minnesota). The three watershed each had different mineral-deposit settings: (1) copper-nickel-platinum group element mineralization (Filson...
GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS...
Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota
The table contains oxide and cation compositions of olivine grains from drill core of the Duluth Complex, Minnesota. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (wt%). The cations were calculated based on the oxide compositions and are reported in mole percent (mol%). Olivine is a magnesium iron orthosilicate mineral with the...
Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota
The table contains oxide and cation compositions of feldspar grains from drill core of the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are are reported in weight percent (wt%). The cations were then calculated and are reported in mole percent (mol%). Feldspar grains are a group of rock-forming tectosilicate minerals with potassium (K), sodium (Na...
Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota
The table contains oxide and cation compositions of pyroxene grains from drill core in the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (we%). The cations were calculated from the oxide concentrations and are reported in mole percent (mol%). Pyroxene minerals are a group of rock-forming inosilicate minerals with...
Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota
This table reports major, minor, and trace element compositions of bulk drill core samples from the Duluth Complex, Minnesota. Major elements were measured using wavelength dispersive X-ray fluorescence (XRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES); minor and trace elements were determined using ICP-AES, inductively coupled plasma mass spectrometry (ICP-MS)...
Filter Total Items: 43
Mineral deposits of the Mesoproterozoic Midcontinent Rift system in the Lake Superior region – A space and time classification Mineral deposits of the Mesoproterozoic Midcontinent Rift system in the Lake Superior region – A space and time classification
The Mesoproterozoic Midcontinent Rift System (MRS) of North America hosts a diverse suite of magmatic and hydrothermal mineral deposits in the Lake Superior region where rift rocks are exposed at or near the surface. Historically, hydrothermal deposits, such as Michigan’s native copper deposits and the White Pine sediment-hosted stratiform copper deposit, were major MRS metal producers...
Authors
Laurel G. Woodruff, Klaus J. Schulz, Suzanne W. Nicholson, Connie L. Dicken
Mineral resource database for deposits related to the Mesoproterozoic Midcontinent Rift System, United States and Canada Mineral resource database for deposits related to the Mesoproterozoic Midcontinent Rift System, United States and Canada
The Midcontinent Rift System (MRS) of North America is one of the world’s largest continental rifts and has an age of 1.1 Ga (giga-annum). The MRS hosts a diverse suite of magmatic and hydrothermal mineral deposits in the Lake Superior region where rift rocks are exposed at or near the surface. As part of the construction of a database summarizing information on mineral deposits in the...
Authors
Laurel G. Woodruff, Klaus J. Schulz, Connie L. Dicken, Suzanne W. Nicholson
Assessing the influence of natural copper-nickel-bearing bedrocks of the Duluth Complex on water quality in Minnesota, 2013–15 Assessing the influence of natural copper-nickel-bearing bedrocks of the Duluth Complex on water quality in Minnesota, 2013–15
The U.S. Geological Survey, in cooperation with the University of Minnesota-Duluth Natural Resources Research Institute, completed an assessment of regional water quality in areas of potential base-metal mining in Minnesota. Bedrock, soil, streambed sediment, and surface-water samples were collected in three watersheds that cross the basal part of the Duluth Complex with different...
Authors
Sarah M. Elliott, Perry M. Jones, Laurel G. Woodruff, Carrie E. Jennings, Aliesha L. Krall, Daniel L. Morel
Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin, Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin,
In response to a need for information on potential domestic sources of critical minerals, the Earth Mapping Resources Initiative (Earth MRI) was established to identify and prioritize areas for acquisition of new geologic mapping, geophysical data, and elevation data to improve our knowledge of the geologic framework of the United States. Phase 1 of Earth MRI concentrated on those...
Authors
Jane M. Hammarstrom, Connie L. Dicken, Warren C. Day, Albert H. Hofstra, Benjamin J. Drenth, Anjana K. Shah, Anne E. McCafferty, Laurel G. Woodruff, Nora K. Foley, David A. Ponce, Thomas P. Frost, Lisa L. Stillings
Soil mineralogy and geochemistry along a north-south transect in Alaska and the relation to source-rock terrane Soil mineralogy and geochemistry along a north-south transect in Alaska and the relation to source-rock terrane
Soils collected along a predominately north-south transect in Alaska were used to evaluate regional differences in the soil mineralogy and geochemistry in the context of a geotectonic framework for Alaska. The approximately 1,395-kilometer-long transect followed the Dalton, Elliott, and Richardson Highways from near Prudhoe Bay to Valdez. Sites were selected with a site spacing of...
Authors
Bronwen Wang, Chad P. Hults, Dennis D. Eberl, Laurel G. Woodruff, William F. Cannon, Larry P. Gough
Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United States Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United States
Between 2007 and 2013, the U.S. Geological Survey conducted a low-density (1 site per 1,600 square kilometers, 4,857 sites) geochemical and mineralogical survey of soils in the conterminous United States. The sampling protocol for the national-scale survey included, at each site, a sample from a depth of 0 to 5 centimeters, a composite of the soil A horizon, and a deeper sample from the...
Authors
David B. Smith, Federico Solano, Laurel G. Woodruff, William F. Cannon, Karl J. Ellefsen
Science and Products
Geochemical characterization of solid media from three watersheds that transect the basal contact of the Duluth Complex, northeastern Minnesota Geochemical characterization of solid media from three watersheds that transect the basal contact of the Duluth Complex, northeastern Minnesota
To document regional water quality in areas of potential base-metal mining, bedrock, soil, streambed sediment, and surface-water samples were collected and analyzed in three watersheds that cross the basal part of the Duluth Complex (northeastern Minnesota). The three watershed each had different mineral-deposit settings: (1) copper-nickel-platinum group element mineralization (Filson...
GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS...
Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota
The table contains oxide and cation compositions of olivine grains from drill core of the Duluth Complex, Minnesota. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (wt%). The cations were calculated based on the oxide compositions and are reported in mole percent (mol%). Olivine is a magnesium iron orthosilicate mineral with the...
Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota
The table contains oxide and cation compositions of feldspar grains from drill core of the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are are reported in weight percent (wt%). The cations were then calculated and are reported in mole percent (mol%). Feldspar grains are a group of rock-forming tectosilicate minerals with potassium (K), sodium (Na...
Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota
The table contains oxide and cation compositions of pyroxene grains from drill core in the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (we%). The cations were calculated from the oxide concentrations and are reported in mole percent (mol%). Pyroxene minerals are a group of rock-forming inosilicate minerals with...
Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota
This table reports major, minor, and trace element compositions of bulk drill core samples from the Duluth Complex, Minnesota. Major elements were measured using wavelength dispersive X-ray fluorescence (XRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES); minor and trace elements were determined using ICP-AES, inductively coupled plasma mass spectrometry (ICP-MS)...
Filter Total Items: 43
Mineral deposits of the Mesoproterozoic Midcontinent Rift system in the Lake Superior region – A space and time classification Mineral deposits of the Mesoproterozoic Midcontinent Rift system in the Lake Superior region – A space and time classification
The Mesoproterozoic Midcontinent Rift System (MRS) of North America hosts a diverse suite of magmatic and hydrothermal mineral deposits in the Lake Superior region where rift rocks are exposed at or near the surface. Historically, hydrothermal deposits, such as Michigan’s native copper deposits and the White Pine sediment-hosted stratiform copper deposit, were major MRS metal producers...
Authors
Laurel G. Woodruff, Klaus J. Schulz, Suzanne W. Nicholson, Connie L. Dicken
Mineral resource database for deposits related to the Mesoproterozoic Midcontinent Rift System, United States and Canada Mineral resource database for deposits related to the Mesoproterozoic Midcontinent Rift System, United States and Canada
The Midcontinent Rift System (MRS) of North America is one of the world’s largest continental rifts and has an age of 1.1 Ga (giga-annum). The MRS hosts a diverse suite of magmatic and hydrothermal mineral deposits in the Lake Superior region where rift rocks are exposed at or near the surface. As part of the construction of a database summarizing information on mineral deposits in the...
Authors
Laurel G. Woodruff, Klaus J. Schulz, Connie L. Dicken, Suzanne W. Nicholson
Assessing the influence of natural copper-nickel-bearing bedrocks of the Duluth Complex on water quality in Minnesota, 2013–15 Assessing the influence of natural copper-nickel-bearing bedrocks of the Duluth Complex on water quality in Minnesota, 2013–15
The U.S. Geological Survey, in cooperation with the University of Minnesota-Duluth Natural Resources Research Institute, completed an assessment of regional water quality in areas of potential base-metal mining in Minnesota. Bedrock, soil, streambed sediment, and surface-water samples were collected in three watersheds that cross the basal part of the Duluth Complex with different...
Authors
Sarah M. Elliott, Perry M. Jones, Laurel G. Woodruff, Carrie E. Jennings, Aliesha L. Krall, Daniel L. Morel
Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin, Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin,
In response to a need for information on potential domestic sources of critical minerals, the Earth Mapping Resources Initiative (Earth MRI) was established to identify and prioritize areas for acquisition of new geologic mapping, geophysical data, and elevation data to improve our knowledge of the geologic framework of the United States. Phase 1 of Earth MRI concentrated on those...
Authors
Jane M. Hammarstrom, Connie L. Dicken, Warren C. Day, Albert H. Hofstra, Benjamin J. Drenth, Anjana K. Shah, Anne E. McCafferty, Laurel G. Woodruff, Nora K. Foley, David A. Ponce, Thomas P. Frost, Lisa L. Stillings
Soil mineralogy and geochemistry along a north-south transect in Alaska and the relation to source-rock terrane Soil mineralogy and geochemistry along a north-south transect in Alaska and the relation to source-rock terrane
Soils collected along a predominately north-south transect in Alaska were used to evaluate regional differences in the soil mineralogy and geochemistry in the context of a geotectonic framework for Alaska. The approximately 1,395-kilometer-long transect followed the Dalton, Elliott, and Richardson Highways from near Prudhoe Bay to Valdez. Sites were selected with a site spacing of...
Authors
Bronwen Wang, Chad P. Hults, Dennis D. Eberl, Laurel G. Woodruff, William F. Cannon, Larry P. Gough
Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United States Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United States
Between 2007 and 2013, the U.S. Geological Survey conducted a low-density (1 site per 1,600 square kilometers, 4,857 sites) geochemical and mineralogical survey of soils in the conterminous United States. The sampling protocol for the national-scale survey included, at each site, a sample from a depth of 0 to 5 centimeters, a composite of the soil A horizon, and a deeper sample from the...
Authors
David B. Smith, Federico Solano, Laurel G. Woodruff, William F. Cannon, Karl J. Ellefsen