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Eric D Anderson

Eric Anderson is a Research Geophysicist with the Geology, Geophysics, and Geochemistry Science Center.

Science and Products

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Red Mountain CO

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...
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center
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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...
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geophysical survey index map

National Geophysical Data Retrieval and Integration Project

This project helped to streamline the workflow from geophysical data acquisition to data distribution, and additionally provided user support for integration and interpretation of these complex data sets. There were four main objectives: 1) contracting geophysical surveys, 2) converting data from analog to digital format, 3) archiving, retrieving, and integrating geophysical data, and 4) outreach.
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center
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National Geophysical Data Retrieval and Integration Project

This project helped to streamline the workflow from geophysical data acquisition to data distribution, and additionally provided user support for integration and interpretation of these complex data sets. There were four main objectives: 1) contracting geophysical surveys, 2) converting data from analog to digital format, 3) archiving, retrieving, and integrating geophysical data, and 4) outreach.
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Airborne Geophysical Survey Inventory of the Conterminous United States, Alaska, Hawaii, and Puerto Rico (ver. 3.0, November 2021)

This data release is a compilation of the locations of airborne geophysical surveys in the United States. The inventory documents public airborne geophysical surveys primarily flown by or contracted by the USGS from 1943 to present. In addition, surveys from the State of Alaska, Department of Natural Resources, Division of Geological and Geophysical Surveys (DGGS): Airborne GeophysWeb, the Bureau
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

A snapshot of stakeholder science needs related to drought in the Colorado River Basin

Stakeholder science needs were determined by reviewing more than 200 recently published literature items and web pages from Colorado River Basin (CRB) stakeholders. These stakeholder communications were used to characterize over 400 stakeholder science needs by reviewing their priorities, strategies, issues, missions, and concerns related to drought in the CRB. Members of the CRB Integrated Scienc
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Nevada Water Science Center

Data and results for GIS-based identification of areas that have resource potential for lode gold deposits in Alaska

This data release contains the analytical results and evaluated source data files of geospatial analyses for identifying areas in Alaska that may be prospective for different types of lode gold deposits, including orogenic, reduced-intrusion-related, epithermal, and gold-bearing porphyry. The spatial analysis is based on queries of statewide source datasets of aeromagnetic surveys, Alaska Geochemi
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Alaska Science Center

Principal facts of regional gravity data in the central Upper Peninsula, Michigan, and northeastern Wisconsin

Gravity data were collected from 2016 through 2019 to assist in mapping surface and subsurface geology in the central Upper Peninsula of Michigan and in neighboring northeastern Wisconsin. This data release provides principal facts for 1536 new gravity stations that were acquired to supplement existing public gravity data coverage.
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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

Updated aeromagnetic and gravity anomaly compilations and elevation-bathymetry models over Lake Superior

New gravity and magnetic compilations and elevation-bathymetry models have been compiled for the Lake Superior region. These data provide continuous sets of observations for geologic interpretations spanning political boundaries such as US States and the US-Canada border where bedrock geology is largely concealed beneath glacial deposits and surface water. These data are providing constraints fo
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Locatable Mineral Assessment Tracts for the U.S. Geological Survey Sagebrush Mineral Resource Assessment Project

The polygon (vector) feature class represents locatable mineral resource assessment tracts (tracts of land) associated with the Department of the Interior (DOI) Sagebrush Focal Areas in Montana, Wyoming and Utah, central Idaho, and the Oregon-Nevada-Idaho border area. The mineral resources tracts are geographic areas that were assessed by the U.S. Geological Survey (USGS) and were determined to be
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Missouri Breaks Project, Montana - Digitized aeromagnetic data

From February 12 to March 8, 1981, EG and G Geometrics conducted an aeromagnetic survey in Montana for Anaconda Copper Company. A Piper Navajo aircraft was used to conducted the survey. The survey was flown along north-south flightlines spaced 660 feet at a nominal height of 450 feet above the terrain. Five uniformly spaced east-west tie-lines were also flown. During processing, the International
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Precambrian basement structure map of the continental United States - An interpretation of geologic and aeromagnetic data

The Precambrian basement rocks of the continental United States are largely covered by younger sedimentary and volcanic rocks, and the availability of updated aeromagnetic data (NAMAG, 2002) provides a means to infer major regional basement structures and tie together the scattered, but locally abundant, geologic information. Precambrian basement structures in the continental United States have

Geologic map of Big Bend National Park, Texas

The purpose of this map is to provide the National Park Service and the public with an updated digital geologic map of Big Bend National Park (BBNP). The geologic map report of Maxwell and others (1967) provides a fully comprehensive account of the important volcanic, structural, geomorphological, and paleontological features that define BBNP. However, the map is on a geographically distorted plan
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Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center
Filter Total Items: 46

Geology and mineral resources of the North-Central Idaho Sagebrush Focal Area: Chapter C in <em>Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming</em>

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
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Energy and Minerals, 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 North-Central Montana Sagebrush Focal Area: Chapter D in <em>Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming</em>

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
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Energy and Minerals, 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 <em>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
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Energy and Minerals, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center, National Minerals Information Center

The F'derik-Zouerate iron district: Mesoarchean and Paleoproterozoic iron formation of the Tiris Complex, Islamic Republic of Mauritania

High-grade hematitic iron ores (of HIF, containing 60-65 wt%Fe) have been mined in Mauritania since 1952 from Superior-type iron deposits of the F'derik-Zouerate district.  Depletion of the high-grade ores in recent years has resulted in new exploration projects focused on lower-grade magnetite ores occurring in Algoma-type banded iron formation (of BIF, containing ca. 35 wt% Fe).  Mauritania is t
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Energy and Minerals, Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Book review: Michael Dentith and Stephen T. Mudge: Geophysics for the mineral exploration geoscientist

No abstract available.
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Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Basement domain map of the conterminous United States and Alaska

The basement-domain map is a compilation of basement domains in the conterminous United States and Alaska designed to be used at 1:5,000,000-scale, particularly as a base layer for national-scale mineral resource assessments. Seventy-seven basement domains are represented as eighty-three polygons on the map. The domains are based on interpretations of basement composition, origin, and architecture
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Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Database of mineral deposits in the Islamic Republic of Mauritania (phase V, deliverables 90 and 91): Chapter S in <i>Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)</i>

Three ore deposits databases from previous studies were evaluated and combined with new known mineral occurrences into one database, which can now be used to manage information about the known mineral occurrences of Mauritania. The Microsoft Access 2010 database opens with the list of tables and forms held within the database and a Switchboard control panel from which to easily navigate through th
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Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69): Chapter H in <i>Second projet de renforcement institutionnel du secteur minier de la République Islamique de

The gold resources of Mauritania presently include two important deposits and a series of poorly studied prospects. The Tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the Rgueïbat Shield and defines a world-class Paleoproterozoic(?) orogenic gold ore system. The producing Guelb Moghrein deposit occurs along a shear zone in Middle Archean rock
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Mineral potential for nickel, copper, platinum group elements(PGE), and chromium deposits hosted in ultramafic rocks in the Islamic Republic of Mauritania (phase V, deliverable 67): Chapter G in <i>Second projet de renforcement institutionnel du secteur m

PRISM-I summary documents mention the presence of mafic-ultramafic igneous intrusive rocks in several areas of Mauritania and a number of chromium (Cr) and copper-nickel (Cu-Ni (±Co, Au)) occurrences associated with them. Permissive geologic settings generally include greenstone belts of any age, layered mafic-ultramafic and unlayered gabbro-anorthosite intrusive complexes in cratonic settings, op
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Synthesis of geophysical data (phase V, deliverable 55): Chapter B in <i>Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)</i>

Aeromagnetic and radiometric data were used to map shallow Precambrian basement lithology and structure and determine the depth to magnetic basement, which in most cases, corresponds to the depth to crystalline basement of interest for mineral exploration. These depths, along with those determined from gravity data, help identify basins with hydrologic potential. In addition, the magnetic data wer
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Algoma-, Superior-, and oolitic-type iron deposits of the Islamic Republic of Mauritania (phase V, deliverable 83): Chapter O in <i>Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)</i>

High-grade hematitic iron ores (or HIF, containing 60–65 percent Fe) have been mined in Mauritania from Superior-type iron deposits since 1952. Depletion of the high grade ores in recent years has resulted in a number of new projects focused on lower grade magnetite ores in Algoma-type banded iron formation (or BIF, containing approximately 35 percent Fe). Large deposits of oolitic-type iron ores
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Timing of ore-related magmatism in the western Alaska Range, southwestern Alaska

This report presents isotopic age data from mineralized granitic plutons in an area of the Alaska Range located approximately 200 kilometers to the west-northwest of Anchorage in southwestern Alaska. Uranium-lead isotopic data and trace element concentrations of zircons were determined for 12 samples encompassing eight plutonic bodies ranging in age from approximately 76 to 57.4 millions of years
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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