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Laurel G Woodruff

Laurel Woodruff is a Research Geologist with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.

Science and Products

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Image shows a map if minerals near Lake Superior

Synthesis of the Tectonic, Magmatic, and Metallogenic Evolution of the Midcontinent Rift System

The overall project objective is to develop a comprehensive synthesis of the tectonic, magmatic, and metallogenic evolution of the Midcontinent Rift System (MRS) through time by integrating geophysical, magmatic, and geochemical data and to create 3-D models of the rift over its evolution.
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Mineral Resources Program, Geology, Energy & Minerals Science Center
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Synthesis of the Tectonic, Magmatic, and Metallogenic Evolution of the Midcontinent Rift System

The overall project objective is to develop a comprehensive synthesis of the tectonic, magmatic, and metallogenic evolution of the Midcontinent Rift System (MRS) through time by integrating geophysical, magmatic, and geochemical data and to create 3-D models of the rift over its evolution.
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example soil geochemistry data

Application of the National-Scale Soil Geochemical and Mineralogical Data for the Conterminous U.S.

Project goals were to produce interpretive products based on the exising national-scale geochoemical and mineralogical data and maps for soils of the conterminous U.S.
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Energy & Minerals Science Center
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Application of the National-Scale Soil Geochemical and Mineralogical Data for the Conterminous U.S.

Project goals were to produce interpretive products based on the exising national-scale geochoemical and mineralogical data and maps for soils of the conterminous U.S.
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Density and magnetic susceptibility measurements on Precambrian rocks in the Iron Mountain-Menominee region, Michigan-Wisconsin

The U.S. Geological Survey (USGS) collected rock physical property measurements to help understand causative sources of gravity and magnetic survey anomalies in the Iron Mountain-Menominee region, Michigan-Wisconsin. A total of 2,356 measurements of magnetic susceptibility and density from 152 locations have been conducted on Precambrian rocks. The measurements aid in interpretation of newly acqui
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Geology, Geophysics, and Geochemistry Science Center

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 Creek), (2)
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Mineral Resources Program, Geology, Energy & Minerals Science Center
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Integrated geophysical analysis provides an alternate interpretation of the northern margin of the North American Midcontinent Rift System, Central Lake Superior

The Midcontinent Rift System (MRS) is a 1.1 Ga sequence of voluminous basaltic eruptions and multiple intrusions followed by widespread sedimentation that extends across the Midcontinent and northern Great Lakes region of North America. Previous workers have commonly used seismic-reflection data (Great Lakes International Multidisciplinary Program on Crustal Evolution [GLIMPCE] line A) to demonstr
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Ecosystems, Geology, Geophysics, and Geochemistry Science Center, Northern Rocky Mountain Science Center

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 geologic terrane
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Energy and Minerals, Mineral Resources Program, Geology, Energy & Minerals Science Center, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center

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 MRS, data f
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Mineral Resources Program

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 mineral-deposit
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Upper Midwest Water Science Center

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 approximately 10
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Energy and Minerals, Mineral Resources Program, Geology, Energy & Minerals Science Center, Alaska Science Center

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 soil C hor
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Energy and Minerals, Mineral Resources Program, Geology, Energy & Minerals Science Center, Geology, Geophysics, and Geochemistry Science Center

Titanium

Titanium is a mineral commodity that is essential to the smooth functioning of modern industrial economies. Most of the titanium produced is refined into titanium dioxide, which has a high refractive index and is thus able to impart a durable white color to paint, paper, plastic, rubber, and wallboard. Because of their high strength-to-weight ratio and corrosion resistance, titanium metal and tita
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Mineral Resources Program, Geology, Energy & Minerals Science Center, National Minerals Information Center

Solid-phase arsenic speciation in aquifer sediments: A micro-X-ray absorption spectroscopy approach for quantifying trace-level speciation

e of this research is to identify the solid-phase sources and geochemical mechanisms of release of As in aquifers of the Des Moines Lobe glacial advance. The overarching concept is that conditions present at the aquifer-aquitard interfaces promote a suite of geochemical reactions leading to mineral alteration and release of As to groundwater. A microprobe X-ray absorption spectroscopy (lXAS) appro
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Water Resources, Geology, Energy & Minerals Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

The distribution of selected elements and minerals in soil of the conterminous United States

In 2007, the U.S. Geological Survey initiated a low-density (1 site per 1600 km2, 4857 sites) geochemical and mineralogical survey of soil of the conterminous United States as part of the North American Soil Geochemical Landscapes Project. Three soil samples were collected, if possible, from each site; (1) a sample from a depth of 0 to 5 cm, (2) a composite of the soil A-horizon, and (3) a deeper
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Geology, Energy & Minerals Science Center

Reaction modeling of drainage quality in the Duluth Complex, northern Minnesota, USA

Reaction modeling can be a valuable tool in predicting the long-term behavior of waste material if representative rate constants can be derived from long-term leaching tests or other approaches. Reaction modeling using the REACT program of the Geochemist’s Workbench was conducted to evaluate long-term drainage quality affected by disseminated Cu-Ni-(Co-)-PGM sulfide mineralization in the basal zon
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Geology, Energy & Minerals Science Center

Copper toxicity and organic matter: Resiliency of watersheds in the Duluth Complex, Minnesota, USA

We estimated copper (Cu) toxicity in surface water with high dissolved organic matter (DOM) for unmined mineralized watersheds of the Duluth Complex using the Biotic Ligand Model (BLM), which evaluates the effect of DOM, cation competition for biologic binding sites, and metal speciation. A sediment-based BLM was used to estimate stream-sediment toxicity; this approach factors in the cumulative ef
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Geology, Energy & Minerals Science Center

Occurrence model for magmatic sulfide-rich nickel-copper-(platinum-group element) deposits related to mafic and ultramafic dike-sill complexes

Magmatic sulfide deposits containing nickel (Ni) and copper (Cu), with or without (±) platinum-group elements (PGE), account for approximately 60 percent of the world’s nickel production. Most of the remainder of the Ni production is derived from lateritic deposits, which form by weathering of ultramafic rocks in humid tropical conditions. Magmatic Ni-Cu±PGE sulfide deposits are spatially and gene
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Mineral Resources Program, Geology, Energy & Minerals Science Center, Geology, Geophysics, and Geochemistry Science Center

Bedrock geologic map of the Port Wing, Solon Springs, and parts of the Duluth and Sandstone 30' x 60' quadrangles, Wisconsin and Minnesota

No abstract available.
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Geology, Energy & Minerals Science Center

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