GIS, supplemental data table, and references for focus areas of potential domestic resources of critical minerals and related commodities in the United States and Puerto Rico

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What does this data set describe?

GIS, supplemental data table, and references for focus areas of potential domestic resources of critical minerals and related commodities in the United States and Puerto Rico
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 36 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 rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, Federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals.

The USGS has identified broad areas within the United States to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the United States. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report:

Hammarstrom, J.M., Dicken, C.L., Woodruff, L.G., Andersen, A.K., Brennan, S., Day, W.C., Drenth, B.J., Foley, N.K., Hall, S., Hofstra, A.H., McCafferty, A.E., Shah, A.K., and Ponce, D.A., 2022, Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico—Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadium, and zirconium, chap. D of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals: U.S. Geological Survey Open-File Report 2019–1023, 65 p.,
The GIS data consist of a polygon layer, or “feature class”, which depicts the locations of focus areas, that might control the distribution of mineral deposits. Individual focus areas may be represented by one or more polygons. When a focus area is defined by more than one polygon, the polygons are grouped to form a “multi-part” feature in the GIS data. For example, the focus area pertaining to the Phosphoria Formation across multiple States consists of 984 polygons. These polygons are grouped and appear as a single record in the GIS attribute table with the UID “RM338”. In all, there are over 59,000 polygons that make up 833 focus areas. Polygons representing different focus areas may overlap. Viewing focus areas as outlines without color fills and with text labels will show where polygons overlap.

Data are provided in ArcGIS 10.8.1 file geodatabase (.gdb) and shapefile formats. The user is also provided a State boundary layer feature class published by Esri (2012) that was modified to include attribute information identifying the four regions used in the study – east, central, west, and Alaska. focusAreas_emri.gdb file geodatabase includes the following:

focusAreas_emri: potential data acquisition areas represented as polygons. states_studyRegions: State boundaries that include study area regions.

Table data are provided as a single excel work sheet with tabs, listed below (as well as comma separated values (.csv) files.) Abbreviations - list of abbreviations used in the data set. Explanations - describes each attribute in the EMRI focus area tab as well as related GIS field name. For example, 'Critical mineral commodities' is the column name in the table and it is called 'CritMin' in the focusAreas_emri GIS table. Additional explanations are below for descriptions of fields in the References tab. EMRI focus areas - full table of attributes for the focus areas. References - table that lists the short reference, full citation, and links where available. * status defined in Explanations tab. Mineral Systems - table 1 modified from Hofstra and Kreiner (2020) that relates critical minerals and commodities to deposit types and mineral systems.

Esri, 2012, USA States: Esri Data & Maps for ArcGIS, 2012 – World, Europe, and United States, Redlands, CA.

These data are published as a Science Base Data Release, however the Hammarstrom and others (2022) Open-File Report 2019–1023 contains the discussion of Earth MRI and the rationale and methods used to develop these geospatial data (
  1. How might this data set be cited?
    Dicken, Connie L., Woodruff, Laurel G., Hammarstrom, Jane M., and Crocker, Kelsey E., 20221101, GIS, supplemental data table, and references for focus areas of potential domestic resources of critical minerals and related commodities in the United States and Puerto Rico: U.S. Geological Survey, Denver, CO.

    Online Links:

    Additional information about Originators: Connie L. Dicken, Jane M. Hammarstrom, Laurel G. Woodruff, Kelsey E. Crocker,
    This is part of the following larger work.

    Hammarstrom, Jane M., Dicken, Connie L., Woodruff, Laurel G., Andersen, Allen K., Brennan, Sean, Day, Warren C., Drenth, Benjamin J., Foley, Nora K., Hall, Susan, Hofstra, Albert H., McCafferty, Anne E., Shah, Anjana K., and Ponce, David A., 2022, Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico — Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadium, and zirconium: US Geological Survey, Reston, VA.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -173.0000
    East_Bounding_Coordinate: -66.0000
    North_Bounding_Coordinate: 72.0000
    South_Bounding_Coordinate: 18.0000
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 2022
    publication date
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: Vector Digital Data Set (Polygon)
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (833)
    2. What coordinate system is used to represent geographic features?
      The map projection used is Albers Conical Equal Area.
      Projection parameters:
      Standard_Parallel: 29.5
      Standard_Parallel: 45.5
      Longitude_of_Central_Meridian: -96.0
      Latitude_of_Projection_Origin: 37.5
      False_Easting: 0.0
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in meters
      The horizontal datum used is North_American_Datum_1983.
      The ellipsoid used is GRS_1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.
  7. How does the data set describe geographic features?
    focusAreas_emri Attribute Table
    Table containing attribute information associated with the data set. (Source: Producer defined)
    A unique identifier for each focus area based on subregion and a 4 digit number. (Source: USGS authors) An alphanumeric identifier formatted as XX#### where XX represents the subregion and the #### is a number. The value of subregion can be Alaska (AK), Hawaii (HI), North Central (NC), Northeast (NE), Northwest (NW), Rocky Mountains (RM), South Central (SC), Southeast (SE), or Southwest (SW). Some focus areas may be two or more polygons grouped together, or a “multi-part”. A focus area may also be part of more than one subregion, but only one is listed.
    An identifier created by the focus area primary author that captured subregion or State. Useful to retain link to original author's records. (Source: USGS authors) Author id to retain link with original records.
    Study region within the United States. (Source: USGS authors) Regions include Alaska, East, Central, and West. States (including District of Columbia and Puerto Rico) were grouped into regions for purposes of the study as follows: Alaska (AK); East (AL, CT, DC, DE, FL, GA, KY, MA, MD, ME, MS, NC, NH, NJ, NY, OH, PA, PR, RI, SC, TN, VA, VT, WV); Central (AR, IL, IN, IA, KS, LA, MI, MN, MO, NE, ND, OK, SD, WI); and West (AZ, CA, CO, HI, ID, MT, NM, NV, OR, TX, UT, WA, WY).
    9 study subregions within the United States. (Source: USGS authors) Alaska (AK), Hawaii (HI), Northwest (NW), Southwest (SW), Rocky Mountains (RM), North Central (NC), South Central (SC), Northeast (NE), and Southeast (SE). Note that Puerto Rico is included with the Southeast subregion.
    States included in the focus area listed in alphabetical order. (Source: USGS authors) District of Columbia, Puerto Rico, Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, and Wyoming.
    A descriptive name for the focus area. May be a geographic area, a mining district, a mineral belt, or an age/lithologic term. (Source: USGS authors) Informal names assigned by the USGS to distinguish focus areas.
    Type of mineral system. (Source: Hofstra and Kreiner (2020))
    Alkalic PorphyryAlkalic porphyry systems form in oceanic and continental magmatic arcs and in continental rifts by similar processes from fluids exsolved from more fractionated alkalic plutons and stocks. Resulting ore deposits tend to be more enriched in Au, Te, Bi, and V.
    ArsenideArsenide systems form in continental rifts where deep-seated, oxidized, metal-rich, metamorphic basement brines ascend to shallow levels. Native elements (Ag, Bi, As), Ni-, Co- and Fe-mono-, di- and sulf-arsenides precipitate by reduction as hydrocarbons, graphite, or sulfide minerals are oxidized to form carbonates and barite.
    Basin Brine PathBasin brine path systems emanate from marine evaporite basins and extend downward and laterally through permeable strata to discharge points in the ocean. Limestone is replaced by reflux dolomite at low temperatures and hydrothermal dolomite at high temperatures. Basin brines evolve to become ore fluids by scavenging metals from various rock types along gravity-driven flow paths. The mineralogy of the aquifers controls the redox and sulfidation state of the brine and the suite of elements that can be scavenged. Copper and Pb-Zn sulfide deposits form where oxidized brines encounter reduced S. Unconformity U deposits form where oxidized brines are reduced. Barium and Sr deposits form where reduced brines encounter marine sulfate or carbonate.
    Carlin-typeCarlin-type systems occur in continental magmatic arcs, but are remote from subjacent stocks and plutons. Consequently, ore fluids consist largely of meteoric water containing volatiles discharged from deep intrusions. Ore fluids scavenge elements from carbonaceous pyritic sedimentary rocks as they convect through them. Gold ore containing disseminated pyrite forms where acidic reduced fluids dissolve carbonate and sulfidize Fe-bearing minerals in host rocks. Arsenic, Hg, and Tl minerals precipitate by cooling. Stibnite precipitates with quartz by cooling from Au-, As-, Hg-, Tl-depleted fluids.
    Chemical weatheringChemical weathering systems operate in stable areas of low to moderate relief with sufficient rainfall to chemically dissolve and concentrate elements present in various rock types and mineral occurrences by the downward percolation of surface water in the unsaturated zone. Chemical gradients cause different elements to be concentrated at different positions in the weathering profile and at the water table. Bauxite, Ni-laterite, and carbonatite laterite are restricted to tropical climatic zones; others form in temperate and arid climates. Dissolved U is reduced on carbonaceous material in lakes and swamps. Dissolved Mn precipitates at redox interface in lakes.
    Climax-typeClimax-type systems occur in continental rifts with hydrous bimodal magmatism. Aqueous supercritical fluids exsolved from A-type topaz rhyolite plutons and the apices of subvolcanic stocks form a variety of deposit types as they move upward and outward, split into liquid and vapor, react with country rocks, and mix with ground water. The broad spectrum of deposit types results from the large thermal and chemical gradients in these systems. At deep levels, NYF pegmatites emanate from plutons.
    Coeur d-Alene-typeMetamorphic dewatering of moderately oxidized siliciclastic sequences during exhumation with fluid flow along dilatant structures. Metasedimentary host rocks may contain basin brine path Pb-Zn and Cu ± Co deposits.
    Hybrid magmatic REE / basin brine pathThis hybrid system operates where CO2- and HF-bearing magmatic volatiles condense into basinal brines that replace carbonate with fluorspar ± barite, REE, Ti, Nb, and Be, as in the Illinois-Kentucky Fluorspar District and Hicks Dome.
    IOA-IOCGIOA-IOCG systems form in both subduction- and rift-related magmatic provinces. IOA deposits form as hot brine discharged from subvolcanic mafic to intermediate composition intrusions reacts with cool country rocks. Albitite U deposits form at deeper levels where brines albitize country rocks. IOCG deposits form on the roof or periphery of IOA mineralization at lower temperatures, often with involvement of external fluids. Polymetallic skarn, replacement and vein deposits occur outboard from IOCG deposits. Manganese replacement and lacustrine Fe deposits form near or at the paleosurface.
    Lacustrine evaporiteLacustrine evaporite systems operate in closed drainage basins in arid to hyper-arid climatic zones. Elements present in meteoric surface, ground, and geothermal recharge water are concentrated by evaporation. As salinity increases, evaporite minerals typically precipitate in the following sequence: gypsum or anhydrite, halite, sylvite, carnallite, borate. Nitrates are concentrated in basins that accumulate sea spray. Residual brines enriched in Li and other elements often accumulate in aquifers below dry lake beds. Lithium-clay and Li-B-zeolite deposits form where residual brine reacts with lake sediment, ash layers, or volcanic rocks.
    Mafic magmaticMafic magmatic systems generally form in large igneous provinces (LIP) related to mantle plumes or meteorite impacts. Nickel-Cu sulfide ores with PGEs result from settling and accumulation of immiscible sulfide liquids in mafic layered intrusions and ultramafic magma conduits. In layered intrusions, Fe-Ti oxides, chromite and PGE minerals crystalize from evolving parental magmas and are concentrated by physical processes in cumulate layers. In anorthosites, Fe-Ti oxides ± apatite crystalize from residual magmas entrained in plagioclase-melt diapirs. In convergent settings, Alaskan-type intrusions with Fe-Ti oxides and PGE form from mantle melts.
    Magmatic REEMagmatic REE systems typically occur in continental rifts or along translithospheric structures. REE and other elements in mantle-derived ultrabasic, alkaline, and peralkaline (agpaitic) intrusions are enriched by fractionation and separation of immiscible carbonatite melts ± saline hydrothermal liquids. Exsolved magmatic fluids or heated external fluids may deposit REE and other elements in adjacent country rocks.
    Marine chemoclineMarine chemocline systems operate where basin brines discharge into the ocean, resulting in increases in bioproductiviy that can produce metalliferous black shales. Changes in ocean chemistry (for example, oceanic anoxic events) and development of chemoclines result in chemical sedimentation of phosphate and Mn and Fe carbonates and oxides.
    Marine evaporiteMarine evaporite systems operate in shallow restricted epicontinental basins in arid to hyper-arid climatic zones. Sabka dolomite and sedimentary magnesite form in coastal salt flats and lagoons. Elements present in seawater are concentrated by evaporation. As salinity increases, evaporite minerals typically precipitate in the following sequence: gypsum or anhydrite, halite, sylvite. Residual basin brines are enriched in conserved elements, such as Mg and Li. Incursion of fresh water or seawater can produce halite dissolution brines.
    MetamorphicMetamorphic systems recrystallize rocks containing organic carbon or REE phosphate minerals or U minerals. Crystalline magnesite forms by carbonation of peridotite.
    Meteoric convectionLow-sulfidation Au-Ag deposits associated with mantle plume volcanic rocks form under relatively low oxygen and sulfur fugacities, have low base metal contents, and high Au/Ag ratios and Se contents. Low-sulfidation deposits along extensional fault zones that are not associated with proximal, coeval magmatic activity may be underlain by rift-related dikes and sills.
    Meteoric rechargeMeteoric recharge systems operate where oxidized meteoric groundwater displaces reduced connate water in sandstone aquifers that often contain volcanic ash or in granitic intrusions or where such groundwater evaporates at the surface. As oxidized water descends through sandstone aquifers it scavenges U and other elements from detrital minerals and/or volcanic glass. Uranium and other elements precipitate at a redox front with reduced connate water, on carbonaceous material in the aquifers, or ferrous Fe minerals in granite, or at the surface in calcrete by evaporation. In ultramafic rocks, dissolved CO2 in meteoric ground water reacts with Mg-silicates to form magnesite, which may also precipitate in permeable sediment or rocks nearby.
    OrogenicMetamorphic dewatering of sulfidic volcanic and/or sulfidic carbonaceous and/or calcareous siliciclastic sequences during exhumation with fluid flow along dilatant structures. Iron minerals in host rocks are often sulfidized. Metavolcanic host rocks often contain volcanogenic seafloor sulfide deposits.
    PetroleumNickel and V in porphyry complexes are the most abundant metals in plant and animal remains in source rocks and in derived petroleum. Helium is produced by radioactive decay of U and Th in felsic igneous rocks and siliciclastic rocks derived from them. It is released by magmatic heat and/or fracturing and accumulates in gas reservoirs below an impermeable seal.
    PlacerPlacer systems operate in drainage basins and along shorelines where there is either topographic relief and gravity driven turbulent flow of surface water or tidal- and wind-driven wave action. Placer systems concentrate insoluble resistate minerals liberated from various rock types and mineral occurrences by the chemical breakdown and winnowing away of enclosing minerals by the movement of water. The distribution of insoluble resistate minerals is controlled by their size, density and the turbulence of fluid flow.
    Porphyry Cu-Mo-AuPorphyry Cu-Mo-Au systems operate in oceanic and continental magmatic arcs with calc-alkaline compositions. Aqueous supercritical fluids exsolved from felsic plutons and the apices of subvolcanic stocks form a variety of deposit types as they move upward and outward, split into liquid and vapor, react with country rocks, and mix with ground water. The broad spectrum of deposit types results from the large thermal and chemical gradients in these systems.
    Porphyry Sn (granite-related)Granite-related porphyry Sn systems form in back arc or hinterland settings by similar processes from fluids exsolved from more crustally contaminated S-type peraluminous plutons and stocks. At deep levels, LCT pegmatites emanate from plutons. Resulting ore deposits tend to be poor in Cu and Mo and enriched in Li, Cs, Ta, Nb, Sn, W, Ag, Sb and In.
    Reduced Intrusion-relatedReduced intrusion-related systems form in continental magmatic arcs by similar processes from fluids exsolved from calc-alkaline plutons and stocks that assimilated carbonaceous pyritic country rocks. Resulting ore deposits tend to be poor in Cu, Mo, Sn and enriched in W, Au, Ag, Te, Bi, Sb and As.
    Volcanogenic SeafloorVolcanogenic seafloor systems are driven by igneous activity along spreading centers, back arc basins and magmatic arcs. In spreading centers and back arc basins, seawater evolves to become an ore fluid by convection through hot volcanic rocks. In magmatic arcs, ore fluids exsolved from subvolcanic intrusions may mix with convecting seawater. Ore deposits form where hot reduced ore fluids vent into cool oxygenated seawater. Sulfides and sulfates precipitate in or near vents. Manganese and Fe precipitate at chemoclines over wide areas in basins with seafloor hydrothermal activity.
    Type of mineral deposit; if more than one deposit type, they are listed in alphabetical order. (Source: Hofstra and Kreiner (2020)) Mineral deposit type (a) Deposits sharing a relatively wide variety and large number of attributes (Cox and Singer, 1986). (b) A “class representing all the recognized mineral deposits that are defined by physical and genetic factors that can be consistently differentiated from those of other classes or deposit types” (Barton and others, 1995, p. 80).

    Deposit types in this study include: 5 element veins; Albitite uranium; Antimony; Arsenic-thallium-mercury; Barite; Barite (replacement and bedded); Basin brine; Black shale; Calcrete uranium; Carbonate uranium; Carbonatite; Cassiterite; Chromite; Clay; Coal uranium; Copper (sed-hosted and replacement); Copper-zinc sulfide; Cryptocrystalline magnesite; Distal disseminated silver-gold; Fluorspar; Garnet; Gneiss uranium; Gold; Graphite (coal or carbonaceous sed); Greisen; Greisen-S-R beryllium; High sulfidation; High sulfidation gold-silver; Ilmenite/rutile/leucoxene; Iron oxide apatite; Iron oxide copper gold; Iron-manganese; Iron-titanium oxide; Lacustrine manganese ; Lamproite; Lithocap alunite; Lithocap kaolinite; Low sulfidation; Low sulfidation epithermal Au-Ag; Magnesite; Manganese oxide (layers, crusts, nodules); Monazite/xenotime; Natural gas, He; Nickel-cobalt laterite; Nickel-copper-PGE sulfide; Oil and natural gas; Pegmatite LCT; Pegmatite NYF; Peralkaline syenite/granite/rhyolite/alaskite/pegmatites; PGE; PGE (low sulfide); Phosphate; Polymetallic sulfide; Polymetallic sulfide S-R-V; Polymetallic sulfide S-R-V-IS; Porphyry molybdenum; Porphyry/skarn; Porphyry/skarn copper; Porphyry/skarn molybdenum; Potash; Reflux and hydrothermal dolomite; Regolith (Ion adsorption) REE; Replacement manganese; Residual brine; Sabka dolomite; Salt; Sandstone uranium; Sedimentary magnesite; Skarn copper-molybdenum-tungsten; Skarn magnesite; Skarn molybdenum; S-R-V tungsten; Strontium (replacement and bedded); Supergene manganese; Uraninite, autunite-group minerals; Uranium (unconformity and breccia pipe); Volcanogenic beryllium; Volcanogenic uranium; Wolframite/scheelite; Zinc-copper sulfide; Zinc-lead (MVT and sedex); Zircon.
    List of known or potential critical mineral commodities associated with the focus area. (Source: USGS authors) Critical minerals are those listed in the Federal Register as of May 18, 2018 Helium was removed from the list and nickel and zinc added.
    Other commodities associated with the focus area (not on the critical minerals list). Includes primary and minor commodities reported. Commodity names are spelled out, except for REE (rare earth elements) and PGE (platinum group elements). (Source: USGS authors) Includes primary and minor commodities reported. Commodity names are spelled out, except for REE (rare earth elements) and PGE (platinum group elements).
    List of critical minerals definitely known in the focus area (active or past production, resources). (Source: USGS authors) Commodity names are spelled out, except for REE (rare earth elements) and PGE (platinum group elements).
    The entity and attribute information provided here describes the EMRI focus areas tabular data associated with the data set. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the data set.
    The entity and attribute information were generated by the individual and/or agency identified as the originator of the data set. Please review the rest of the metadata record for additional details and information.

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Connie L. Dicken
    • Laurel G. Woodruff
    • Jane M. Hammarstrom
    • Kelsey E. Crocker
  2. Who also contributed to the data set?
    Development of the dataset was funded by the U.S. Geological Survey Mineral Resources Program. The spatial data set and supporting tables were developed by 4 regional teams: Geology, Energy & Minerals Science Center (Reston, VA); Geology, Geophysics, and Geochemistry Science Center (Denver, CO); Geology, Minerals, Energy, and Geophysics Science Center (Spokane, WA and Tucson, AZ); and Alaska Science Center - Geology Office (Anchorage, AK). Database reviews and contributions were made by USGS personnel Heather Parks, Ryan Taylor, Carlin Green, Dan Hayba, Damon Bickerstaff, and Patricia Loferski.

    Alaska Division of Geological and Geophysical Surveys – Werdon, M.B. Arizona Geological Survey - Richardson, C.A. Arkansas Geological Survey - Cannon, C., Chandler, A., and Hanson, W.D. California Geological Survey - Bohlen, S., Callen, B., Gius, F.W., Goodwin, J., Higgins, C., Key, E.L., Marquis, G., Mills, S., Tuzzolino, A., and Wesoloski, C. Colorado Geological Survey - Morgan, M.L., and O'Keeffe, M.K. Connecticut Geological Survey - Thomas, M. Delaware Geological Survey - KunleDare, M., and Tomlinson, J. Florida Geological Survey - Means, H. Geological Survey of Alabama - VanDervoort, D.S., and Whitmore, J.P. Idaho Geological Survey - Berti, C., Gillerman, V.S., and Lewis, R.S. Illinois State Geological Survey - Denny, F.B., Freiburg, J., Scott, E., and Whittaker, S. Indiana Geological and Water Survey - Mastalerz, M., McLaughlin, P.I., and Motz, G. Iowa Geological Survey - Clark, R.J., Kerr, P., and Tassier-Surine, S. Kansas Geological Survey - Husiuk, F., Oborny, S., and Smith, J. Kentucky Geological Survey - Andrews, W.M., Harris, D., Hickman J., and Lukoczki, G. Maine Geological Survey - Beck, F.M., Bradley, D., Marvinney, R., Slack, J., and Whittaker, A.H. Maine Mineral and Gem Museum - Felch, M. Maryland Geological Survey - Kavage Adams, R.H., Brezinski, D.K., Junkin, W., and Ortt, R. Michigan Geological Survey - Yellich, J. Minnesota Department of Natural Resources - Arends, H., Dahl, D.A., and Saari, S. Minnesota Natural Resources Research Institute - Hudak, G.J. Minnesota Geological Survey - Block, A. Missouri Geological Survey - Ellis, T., Lori, L., Pierce, L., Seeger, C.M., and Steele, A. Montana Bureau of Mines and Geology - Gunderson, J., Korzeb, S.L., and Scarberry, K.C. Nevada Bureau of Mines and Geology - Faulds, J., and Muntean, J.L. New Mexico Bureau of Geology and Mineral Resources - Gysi, A., Kelley, S.A., and McLemore, V.T. North Carolina Geological Survey - Chapman, J.S., Farrell, K.M., Taylor, K.B., Thornton, E., and Veach, D. North Dakota Geological Survey - Kruger, N. Ohio Geological Survey - McDonald, J., and Stucker, J. Pennsylvania Geological Survey - Hand, K., and Shank, S.G. South Carolina Geological Survey - Howard, C.S., and Morrow, R.H. South Dakota Geological Survey - Cowman, T., Luczak, J.N., and Myman, T.J. Tennessee Geological Survey - Lemiszki, P. Texas Bureau of Economic Geology - Paine, J. Utah Geological Survey - Boden, T., Mills, S.E., and Rupke, A. Virginia Division of Geology and Mineral Resources - Coiner, L.V., and Lassetter, W.L. Washington Geological Survey - Eungard, D.W., and Skov, R. West Virginia Geological and Economic Survey - Brown, S.R., Dinterman, P., and Moore, J.P. Western Michigan University - Thakurta, J., Harrison, W., and Voice, P. Wisconsin Geological and Natural History Survey - Ames, C., Gotschalk, B., Lodge, R., Stewart, E.K., and Stewart, E. Wyoming State Geological Survey - Gregory, R.W., Lynds, R.M., Mosser, K., Toner, R., and Webber, P.

    U.S. Geological Survey - Anderson, A.K., Bickerstaff, D., Bern, C.R., Brady, S., Brezinski, C., Brock, J., Bultman, M.W., Carter, M.W., Cossette, P.M., Crafford, T., Crocker, K.E., Day, W.C., Dicken, C.L., Drenth, B.J., Emsbo, P., Foley, N.K., Frost, T.P., Gettings, M.E., Grauch, V.J.S., Hall, S.M., Hammarstrom, J.M., Hayes, T.S., Hofstra, A.H., Horton, J.D., Horton, J.W., Hubbard, B.E., Hudson, M., John, D.A., Johnson, M.R., Jones, J.V. III, Kreiner, D.C., Mauk, J.L., McCafferty, A.E., McPhee, D., Merchat, A.J., Nicholson, S.W., Ponce, D.A., Roberts-Ashby, T., Rosera, J., San Juan, C.A., Shah, A.K., Scheirer, D., Siler, D.L., Soller, D.R., Stillings, L.L., Swezey, C.S., Taylor, R.D., Thompson, R., Van Gosen, B.S., Verplanck, P., Vikre, P.G., Walsh, G.J., Woodruff, L.G., and Zurcher, L.
  3. To whom should users address questions about the data?
    Connie Dicken
    U.S. Geological Survey, NORTHEAST REGION
    Mail Stop 954, 12201 Sunrise Valley Dr
    Reston, VA

    703-648-6482 (voice)
    703-648-6252 (FAX)

Why was the data set created?

These geospatial data provide the locations of focus areas to be used for the planning and collection of geophysical, geological, and topographic (lidar) data pertaining to the Earth MRI study of critical mineral resources in the U.S. Focus areas are outlined solely on the basis of geology, regardless of political boundaries. Therefore, areas may include Federal, as well as State, tribal, and private lands, which may or may not be open to exploration and mining activities. These data are shared to meet open data requirements and are suitable for use in Geographic Information Systems (GIS) or other database and geospatial software used to derive maps and perform geospatial analyses.

How was the data set created?

  1. From what previous works were the data drawn?
    Hofstra and Kreiner (2020) (source 1 of 2)
    Hofstra, Albert H., and Kreiner, Douglas C., 20200525, Systems-Deposits-Commodities-Critical Minerals Table for Earth Mapping Resources Initiative (ver. 1.1, May 2021): Open-File Report 2020-1042.

    Online Links:

    Type_of_Source_Media: Digital and/or Hardcopy
    Source_Contribution: Mineral systems, deposit types and commodities for Earth MRI.
    Esri (2012) (source 2 of 2)
    Esri, 2012, USA States: Esri Data & Maps for ArcGIS.

    Online Links:

    Type_of_Source_Media: Digital and/or Hardcopy
    Source_Scale_Denominator: 3000000
    Used for State boundaries and added USGS EMRI regions to the attributes for general use.
  2. How were the data generated, processed, and modified?
    Date: 30-Mar-2021 (process 1 of 1)
    To define focus areas, project teams first evaluated existing data on critical mineral occurrences (deposits, prospects, and showings), past exploration, resources and production, geochemical and geophysical data, and the status of geologic mapping for the eastern, central, and western conterminous U.S. and Alaska. Resulting focus areas ranged from areas with identified resources and past production to areas with geologic characteristics permissive for undiscovered deposits with no known deposits. Specific data needs that could be addressed by the Earth MRI program to better evaluate each focus area for critical mineral potential were summarized.

    The evaluation of existing data formed the rationale for developing polygon features in a GIS. The geospatial delineation of focus areas involved a variety of data sources and approaches. Focus areas for potential 36 critical minerals were developed by querying digital State geologic map data for permissive host rocks based on lithology and age. Other focus areas were derived using generalized outlines of mining districts or mineral belts, distributions of observed occurrences, and in some cases, geochemical and (or) geophysical anomalies associated with deposits.

    Hofstra and Kreiner (2020) table 1 was used to define and categorize focus areas based on a hierarchical data structure of mineral systems and deposit types. Person who carried out this activity:
    Connie Dicken
    U.S. Geological Survey, NORTHEAST REGION
    Mail Stop 954, 12201 Sunrise Valley Dr
    Reston, VA

    703-648-6482 (voice)
    703-648-6252 (FAX)
    Data sources used in this process:
    • Hofstra and Kreiner (2020)
    • Esri (2012)
  3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    The data are intended to be used at regional scales for planning purposes. Unique values in attribute fields were acquired through frequency analyses. The unique values in each attribute field were reviewed and checked for spelling, consistency of terms, accuracy, adherence to established vocabularies, and completeness.
  2. How accurate are the geographic locations?
    The quality of focus areas is highly variable and generally reflects the accuracy of source reports and data. The data are intended to show the general distribution of known mineral deposits and regions as well as areas that potentially contain resources for critical minerals. The data can be queried to identify commodities. The data are intended to be used at regional scales for planning purposes.
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
    Focus areas are based on existing data and reports published 1889–2022. Focus areas are based solely on geologic information and rationale. Focus areas intentionally include areas of incomplete information that could be better understood by the collection of new or additional data.
  5. How consistent are the relationships among the observations, including topology?
    A single focus area may be represented by numerous, dispersed polygons. Where this occurs, the polygons are grouped to form a “multi-part” feature which has a single record in the GIS attribute table. There are over 59,000 polygons that make up 833 multi-part focus areas. Consequently, polygons representing different focus areas may overlap.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints: None. Please see 'Distribution Info' for details.
There is no guarantee concerning the accuracy of the data. Data have been checked to ensure the accuracy. If any errors are detected, please notify the originating office. The U.S. Geological Survey recommends users read all metadata prior to using data. Acknowledgment of the U.S. Geological Survey would be appreciated in products derived from these data. User specifically agrees not to misrepresent the data, nor to imply that changes made were approved or endorsed by the U.S. Geological Survey.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey
    Building 810, Mail Stop 302, Denver Federal Center
    Denver, CO

    1-888-275-8747 (voice)
  2. What's the catalog number I need to order this data set?
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
  4. How can I download or order the data?
    • Availability in digital form:
      Data format: Vector Digital Data Set (Polygon)
      Network links:
    • Cost to order the data: None. No fees are applicable for obtaining the data set.

Who wrote the metadata?

Last modified: 01-Nov-2022
Metadata author:
Connie Dicken
U.S. Geological Survey, NORTHEAST REGION
Mail Stop 954, 12201 Sunrise Valley Dr
Reston, VA

703-648-6482 (voice)
703-648-6252 (FAX)
Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

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