This map sheet with accompanying Geographic Information System (GIS) project is an update of the existing U.S. Geological Survey (USGS) Conterminous U.S. Coal Fields map compiled using data primarily from the USGS National Coal Resource Assessment (NCRA).

The purpose of this report is to present available petrographic and geochemical data for unmineralized rock samples, principally volcanic rocks and to make those data available to ongoing petrogenetic investigations of these rocks.

This report presents and makes data available to ongoing petrogenetic investigations of these rocks. It develops an accurate and current portrayal of their spatial distribution in GIS format while analyzed samples are presented via Excel workbooks.

Systematic geochemical and mineralogical survey of soil horizons analyzed using a consistent set of methods, sample spacing 1 per 1,600 sq km.

Systematic geochemical and mineralogical survey of soil horizons analyzed using a consistent set of methods, sample spacing 1 per 1,600 sq km.

Presents data for mineral deposits and unaltered and hydrothermally altered volcanic rocks. Data presented were acquired in three USGS labs by three different geochronologists. Analytical methods and data derived from each lab are presented separately.

Spatial geologic map with rock type, vents, arcs, landslides, etc. provided in an ESRI geodatabase and KMZ format for Google Earth viewing. Mapsheet with accompanying descriptive pamphlet is provided as a PDF. Petrographic rock summary is also included.

A regional profile on the Utah-Nevada State line reveals a deeply penetrating, broad electrical conductor suggesting the southwestern limit of intact Archean crust is farther north than previously reported with implications for future mineral exploration.

Data from more than 660 gravity stations, 100 line-km of truck-towed magnetometer traverses, and 260 physical-property sites in this area.

Geochemical and mineralogical maps along with a histogram, boxplot, and empirical cumulative distribution function plot for each element or mineral whose data are provided in DS-801

In-place rock magnetic susceptibility measurements for 746 sites are reported in a database. These data, collected from 1991 through 2012, are intended to help improve geophysical modeling of the Earth’s crust in the Western United States.

Interactive web site showing geochemical and mineralogical maps along with a histogram, boxplot, and empirical cumulative distribution function plot for each element or mineral whose data are provided in DS-801

Seventy-seven major components of the North American continent were delineated at a general scale (1:5,000,000); including the general composition, geological environment, and types of primary metals endowments that can be expected in each domain.

Seventy-seven major components of the North American continent were delineated at a general scale (1:5,000,000); including the general composition, geological environment, and types of primary metals endowments that can be expected in each domain.

Airborne surveys measuring the earth's magnetic field, resistivity or other electomagnetic properties, or gamma ray emission over parts of North America.

Digital geologic maps of the US states with consistent lithology, age, GIS database structure, and format

Number and type of mine claims located on Federal lands and registered with the Bureau of Land Management, by year from 1976 through 2007.

Digital geologic map information with a consistent set of attributes, part of a national compilation of similar maps. Available in formats compatible with GIS.

Aeromagnetic surveys of Nevada, merged to form seamless grids across the state. Gravity anomaly data are provided as well. Data provided in a variety of formats.

Gravity observations throughout Nevada combined to provide a consistent collection of point measurements and generate maps.

Overview explaining how and why six different geochemical data sets were produced, and why you might choose to use the data in any one of these instead of the others.

A set of geophysical maps with anomalies that are labeled and keyed to tables containing information on each anomaly and its source.

Geochemical data for unconsolidated sediments (stream sediments, lake sediments, etc.) collected in the US and analyzed by the USGS. These data were originally entered in the PLUTO database, which is now merged into the National Geochemistry Database.

Probabilistic estimates of the amounts of undiscovered gold, silver, copper, lead, and zinc in conventional types of mineral deposits in the United States.

Map and data tables show location, mineralogy, geology, and relevant literature for each mine, prospect, or occurrence

Digital and analog archives comprising more than 1,000 surveys, covering approximately 8,000,000 line-km of data, flown at various flight heights and line spacings

Aeromagnetic anomaly values digitized from older surveys

Geochemistry of soils and other regoliths collected and analyzed by Hans Shacklette and colleagues from 1958 until about 1976.

Principal basement structures formed during the Precambrian in the continental United States based on interpretation of regional aeromagnetic anomaly data of North America.

Characteristics of bedrock and surficial geologic terranes and structural features at various levels of detail. The information provided here are intended for use in the synoptic study of large areas, and are likely not suitable for detailed study of geog

A GIS database of geologic units and structural features in Nevada, with lithology, age, data structure, and format written and arranged just like the other states.

Map includes GIS data for magnesium-rich ultramafic rocks

Compilation of all available chemical data (more than 2,000 samples) for igneous rocks that constitute the southern segment of the ancestral Cascades magmatic arc.

Petrographic and geochemical analyses of 50 outcrop samples and 58 drill core samples.

The U.S. Geological Survey (USGS) and the Bureau of Land Management (BLM) collected stream-sediment and soil samples in order to evaluate the geochemistry of the Humboldt River Basin.

This small database provides information about sedimentary- rock-hosted (Carlin-type) gold deposits in China.

Descriptive mineral deposit model, with locations of known deposits of this type and a few site characteristics.

The long-wavelength (50-2,500 km) content of the regional magnetic anomaly compilation was improved by utilizing a nearly homogeneous a nearly homogeneous set of NURE magnetic surveys flown from 1975 to 1981

National-scale geochemical analysis of stream sediments and soils in the US collected and analyzed under the National Uranium Resource Evaluation program.

National-scale geochemical analysis of water samples in the US collected and analyzed under the National Uranium Resource Evaluation program.

Location and mineralogical characteristics of former mines, prospects, and occurrences of asbestos in the continental US. No asbestos producing mines are currently active. Data here are drawn from several previously published reports.

Radiometric ages of geological materials by K-Ar, Rb-Sr, Sm-Nd, fission track, and U-Th-Pb dating methods. A revision of DDS-14 correcting locations and providing the data in more convenient formats.

Radiometric ages of geological materials by K-Ar, Rb-Sr, Sm-Nd, fission track, and U-Th-Pb dating methods. A revision of DDS-14 correcting locations and providing the data in more convenient formats.

Geochemical data for soils collected in the United States and analyzed by the USGS. The data were originally entered into the in-house PLUTO database. This is a subset of DDS-47.

Mine plants and operations for commodities monitored by the National Minerals Information Center of the USGS. Operations included are those considered active in 2003 and surveyed by the USGS.

Geochemical analysis of rock samples collected and analyzed by the USGS. This dataset includes and supersedes rock data formerly released as "Geochemistry of igneous rocks in the US extracted from the PLUTO database"

MRDS describes metallic and nonmetallic mineral resources throughout the world. Included are deposit name, location, commodity, deposit description, geologic characteristics, production, reserves, resources, and references.

National-scale geochemical analysis of stream sediments and soils in the US, from existing data, reanalysis of existing samples, and new sampling. Goal for sample density is one per 289 square km.

Geochemical analysis of sediment samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are of stream sediment in the continental US and Alaska.

Geochemical analysis of soil samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are from the continental US and Alaska.

Geochemistry of concentrates from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are from the continental US and Alaska.

Deposits, prospects, and permissive tracts for porphyry and sediment-hosted copper resources worldwide, with estimates of undiscovered copper resources.

Symbols indicating mining-related features digitized from historical USGS topographic maps in the western part of the conterminous US. Includes prospect pits, mine shafts and adits, quarries, open-pit mines, tailings piles and ponds, gravel and borrow pit

U.S. Geological Survey (USGS) scientists have completed an assessment of the mineral-resource potential of nearly 10 million acres of Federal and adjacent lands in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming. The assessment of these lands, identifie

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Scanned image of map drawn at 1:5,000,000 scale, projection probably Lambert Conformal Conic, monochrome.

Measurements of the gravitational field vary slightly from place to place due to the composition and structure of Earth's crust. Includes the isostatic and Bouguer anomalies for the conterminous US.

Mining districts, mines, and mineral occurrences (deposits and prospects) within the United States that are reported to contain enrichments of rhenium (Re)

A collection of state geological maps using the same underlying database structure. Updates the preliminary state geologic map compilation released in 2005, with corrections and seven updated state geologic maps as well as seven new state geologic maps.

Reanalysis, using modern methods, of nearly 60,000 NURE-HSSR archived samples collected over parts of Arizona, California, Idaho, Montana, Nevada, New Mexico, and Utah.

Mineral groups identified through automated analysis of remote sensing data acquired by the ASTER system were used to map the type and spatial distribution of hydrothermal alteration, other exposed mineral groups, and green vegetation.

Maps of exposed surface mineral groups derived from automated spectral analysis of Landsat 7 ETM+ and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data.

Geologic occurrence of potential sources of crushed stone and sand and gravel for use as natural aggregate. A summary of the natural aggregate industry is also included. Data are provided in Shapefile format.

Presentation materials discussing types of aggregate, the occurrence of good-quality aggregate, and pointing out where good-quality aggregate is limited. Societal and environmental issues that limit aggregate development are also discussed. Data are provided in PDF and Microsoft PowerPoint.

Explains background, data sources, and methodology used to identify focus areas for potential domestic sources of rare earth elements in non-fuel deposit types.

Miocene calc-alkaline volcanic rocks, part of the southern segment of the ancestral Cascades magmatic arc, are spatially, temporally, and likely genetically associated with precious metal epithermal deposits in the Tonopah, Divide, and Goldfield Districts

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 surve

Gravity investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles

U.S. Geological Survey Scientific Investigations Map 3412 is a series of products that consists of geophysical and geologic maps of Mountain Pass and vicinity, California. Maps A and B (red outline in above map image) are gravity and aeromagnetic maps, re

A developing national-scale geospatial database that will be an authoritative source of information on the most important mines, mineral deposits, and mineral districts of the United States.

Geographic areas identified to target acquisition of geologic mapping, geophysical data, geochemistry, or detailed topographic information to aid research, mineral exploration, and evaluation of critical mineral potential.

Geographic areas within the US where deposits of certain critical mineral resources might be found. With state agencies and other organizations, USGS intends to conduct studies that will help locate critical mineral resources within these areas.

Broad areas within the United States to target acquisition of geologic mapping, geophysical data, geochemical analysis, or detailed topographic information to aid research, mineral exploration, and evaluation of critical mineral potential in these areas.

Geological, geophysical, geochemical, or lidar data acquisition projects funded by the Earth Mapping Resource Initiative (Earth MRI) pertaining to the study of critical mineral resources in the US.

Locations and characteristics of map symbols pertinent to mining appearing on historical USGS topographic maps. Data are provided in Esri file geodatabase and shapefile formats.

Descriptions and analytical data (electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples, a mineral product with commercial applications. Data are provided in CSV format. Descriptions of the samples are provided as PDF reports.

A compilation of previously published mineral potential maps that were used for the Sagebrush Mineral Resource Assessment (SaMiRA) project. Data are provided in CSV, Esri file geodatabase, GeoTiff, and shapefile formats.

GIS for focus areas of potential domestic resources of 11 critical minerals: aluminum, cobalt, graphite, lithium, niobium, platinum group elements, rare earth elements, tantalum, tin, titanium, and tungsten. Version 2.0 of this dataset. Data are provided in CSV, Esri file geodatabase, shapefile, and Microsoft Excel formats.

These data generalize the detailed LR2000 information and related boundaries (for example, small mine claim boundaries) to a larger Public Land Survey System (PLSS) section boundary in order to assist in the analysis of locatable, leasable, and salable minerals for mineral-resource assessment. Data are provided in shapefile format.

Mineral resource assessment information including the input data, parameters, and results output from software that calculates the assessment. Data are provided in CSV format.

Multispectral remote sensing data acquired by Landsat 8 Operational Land Imager (OLI) sensor were analyzed using an automated technique to generate surficial mineralogy and vegetation maps of the conterminous western United States. Data are provided in ERDAS Imagine format.

Estimates of potassium, equivalent uranium, and equivalent thorium for the conterminous United States derived from the USGS national airborne radiometric data compilation analyzed using a Bayesian hierarchical model to produce new grids for this area. Data are provided in CSV and GeoTIFF formats.

Statistical characteristics of the chemical concentration of lithium in the soil C horizon of the conterminous United States. Data are provided in CSV, shapefile, and GeoTIFF formats.

Distribution of the mineral pyrrhotite, an unstable sulfide mineral, across the conterminous United States, to help inform risk assessments. Data are provided in Esri file geodatabase, shapefile, and CSV formats.

Statistical characteristics of the chemical concentration of lanthanum in the soil C horizon of the conterminous United States. Data are provided in CSV, shapefile, and GeoTIFF formats.

Statistical characteristics of the chemical concentration of cobalt in the soil C horizon of the conterminous United States. Data are provided in CSV, shapefile, and GeoTIFF formats.

Compilation of airborne geophysical surveys (magnetic, radiometric, and electromagnetic) with links, for each survey to the data, metadata, and preview images. Includes a measure of quality indicating which surveys are likely most useful for investigations of subsurface mineral deposits. Data are provided in Esri file geodatabase, shapefile, and CSV formats.

Broad areas within the United States to target acquisition of geologic mapping, geophysical data, or detailed topographic information to aid research, mineral exploration, and evaluation of critical mineral potential. Data are provided in Esri file geodatabase, shapefile, Microsoft Excel, and CSV formats..

Data on materials are presented provide an overview of the annual quantities (measured in physical terms) required for the standard of living in the United States and to provide insights into the consumption trajectory that developing countries may follow.

Published ages, dates, analytical information, sample metadata including location, and source citations. The following analytical techniques are represented in the data set: 40Ar/39Ar, K-Ar, U-Th-Pb, Sm-Nd, Rb-Sr, Lu-Hf, fission track, and luminescence. Data are provided in CSV format.

A collection of geoscientific data for this area, provided in the mid-1990s using file formats in common use at that time, which are now obsolete. Much of the data is now available in formats more convenient to users of the 2020s at mrdata.usgs.gov.

Mineral deposit information drawn from USGS databases, industry reports, and scientific literature totalling 681 individual mineral deposits documented to contain critical minerals. Data are provided in Esri file geodatabase, Microsoft Excel, shapefile, and CSV formats.

Maps and data showing the geographic distribution of surficial minerals likely produced by hydrothermal alteration, which may indicate areas permissive of gold and copper mineral deposits.

Maps and data showing the geographic distribution of surficial minerals likely produced by hydrothermal alteration, which may indicate areas permissive of gold and copper mineral deposits.

Gridded data from helicopter study of shallow geologic structures

Geochemical data generated during mineral and environmental assessments for the Bureau of Land Management in northern Nevada, northeastern California, southeastern Oregon, and southwestern Idaho.

Geochemical, geophysical, geological, and mineral resource data supporting an assessment of undiscovered tungsten skarn deposits in this area. Permissive tracts and other information derived from the analysis are provided in shapefile, CSV, and Esri file geodatabase formats.

Chemistry and geologic information for historic ore and ore-related rock samples from mineral deposits in the United States and from archetypal deposits from 27 other countries. Data are provide in Microsoft Access, Microsoft Excel, and CSV formats.

Chemical analyses for 46,955 samples collected in the Great Basin Tungsten assessment area, extracted from the USGS National Geochemical Database. Data are provided in Microsoft Access, Microsoft Excel, and tab-delimited text formats.

Geochemical data from selected USGS projects from the 1960s-1980s that were previously not published as digital data. Includes geochemical analyses from 36,498 samples of various types using analytical methods and instruments that were current when those studies were carried out. Data are provided in Microsoft Access, shapefile, and CSV formats.

Nevada is one of the Earth's premier gold producing regions, accounting for approximately 64 percent of the U.S and nine percent of the world total. The impact of these mines on nearby local economies and on our national balance of payments is profound, a

Includes principal facts (gravity observations) for 2,506 stations.

Maps and geospatial data for (a) geology; (b) tectonics; (c) isostatic gravity anomaly; (d) aeromagnetic anomaly; (e) depth to pre-Cenozoic basement.

Gravity data were collected in support of geologic mapping of the quadrangle. In addition, older gravity data were reprocessed for consistency and included, as well as 250 measurements of density and magnetic susceptibility.

Report describing detailed interpretation of geophysical survey data to draw inferences about subsurface geologic features and likely consequences for the hydrogeologic system.

Grid and flight-line data files provided by the geophysical survey contractors.

Results of analysis in tabular form

Gravity study to help define the shapes of young basins filled with Cenozoic rocks and alluvium, and to identify any possible faults within these basins that might influence the movement of groundwater.

Gridded data for aeromagnetic surveys with contractors' reports describing the data collection

GIS data for geologic units and structural features, with aeromagnetic and gravity maps in PDF

Study aids understanding of local geologic structure and ground-water flow, includes principal facts for 266 gravity stations and physical properties of representative rock samples.

Report with generalized interpretation and Excel tables of gravity and physical property data including an explanations of their formats.

Detailed descriptions of more than 200 mineral districts, mines, and mineral occurrences (deposits, prospects, and showings) within the United States that are reported to contain substantial enrichment of rare earth elements.

Digital flight-line aeromagnetic and aeroradiometric survey data over of the southeast Mojave Desert, parts of California and Nevada. Data files are provided in CSV as well as Geosoft binary database and grid exchange format (GXF).

Magnetotelluric (MT) data from 65 stations collected in 2015 in this area create a regional conductivity model near the Mountain Pass mine.

Site-by-site information on 876 natural occurrences of asbestos reported within the conterminous US. Includes location, mineralogy, geology, and relevant literature for each asbestos site. Data are provided in Microsoft Excel, shapefile, and CSV formats.

Physical properties (density, magnetic susceptibility, and remanent magnetism) from 20,000 rock samples. Data are provided in CSV format.

Rock property measurements including density, magnetic susceptibility, and radiometric concentrations to understand structural and geophysical relationships associated with rare earth element mineral deposits. Data are provided in CSV format.

Physical property measurements rocks from this area, including station identifier, geographic coordinates, rock type, density, magnetic susceptibility, remanent magnetization, declination, and inclination where available. Data are provided in CSV format. Sample locations are provided in shapefile format.

Nearly 10,000 measurements of gravity governed by consistent parameters and adjustments to account for all of the common physical phenomena that affect these measurements. Data are provided in CSV and shapefile formats.

Chemistry and geologic information for nearly 30,000 historic ore and ore-related rock samples from mineral deposits and mining districts in the United States. Data are provided in Microsoft Access and CSV formats.

Describes the methods, procedures, and fundamental reference information that were used throughout the assessment.

Locations of mines, mineral occurrences, and mining districts in this area of active gold mining, with additional information such as commodity, geology, deposit types, activity status, deposit resources, and mine production. Extent of surface workings is also included. Data are provided in Esri file geodatabase, shapefile, Microsoft Excel, and CSV formats.

Magnetotelluric (MT) sounding data collected in 2005 along an east-west profile in this area, to know whether major mining districts in the Northern Nevada Gold Province are underlain by rocks of the Archean Wyoming craton, which are known to contain orogenic gold deposits, or by accreted rocks of the Paleoproterozoic Mojave province.

Magnetotelluric sounding data collected in 2003 along a north-south profile west of Wendover, Nevada, to understand the rocks underlying mineral deposits in this area.

Geochemical analyses of silicate melt inclusions, host quartz phenocrysts, and biotite phenocrysts in samples of these rocks. Data are provided in CSV format.

Detailed descriptions of mineral deposits containing this commodity, including history, production, resource estimates, and geographic features. Data are provided in CSV, shapefile, Microsoft Excel, and Esri file geodatabase formats.

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. Data are provided in Esri file geodatabase and shapefile formats.

Grid and flight-line data files provided to USGS by contract geophysical surveyors

Analytical results for Pb-concentrations and isotopic ratios from about 150 samples of soil A horizon and about 145 samples of soil C horizon collected along a 4000-km east-west transect across the USA.

Geochemical, petrographic, and geochronologic data for samples, principally those of unmineralized Tertiary volcanic rocks, from the Tonopah, Divide, and Goldfield mining districts of west-central Nevada.

Ar/Ar data are reported from minerals and rocks that were collected as part of a mineral resource investigation of this area. Data are provided in CSV format.

U-Pb ages and concentrations of selected trace elements were analyzed in zircon crystals from nine samples of Cenozoic igneous rocks collected in this area. Data are provided in CSV format.

Helium, neon, and argon isotopic compositions contained in fluid inclusions in 25 samples from these mineral deposits. Four mineral separates from the Butte Main Stage vein deposit and two from the Bingham pyrite-enargite vein deposits were also analyzed. Includes some hand samples from underground mine workings and some from mine tailings piles and pits. Data are provided in CSV format.

Detailed descriptions of mineral deposits containing this commodity, including history, production, resource estimates, and geographic features. Data are provided in CSV, shapefile, Microsoft Excel, and Esri file geodatabase formats.

Reprocessed existing gravity data compiled from multiple sources, as well as newly collected gravity and ground magnetic data, and bulk densities and magnetic susceptibilities from outcrop, hand samples, and drill cores. Data are provided in CSV format.

Detailed chemical and isotopic analysis of host and associated rocks within an area that is currently the largest producer of gold in the US. Part of a study of the hydrothermal activity leading to the formation of these gold deposits.

Density and magnetic susceptibility measurements to assist in interpretation of gravity and magnetic anomaly data

Report with gravity station data in a spreadsheet

Gravity station data for several surveys of this area.

Existing and new gravity station data and magnetometer measurements used to infer geologic structure of this area

Gravity surveys and structural interpretation of anomaly data in support of ground-water studies

Principal facts (gravity observations) for 185 new stations

Gravity observations from 99 locations in this area, with free-air, isostatic, and complete Bouguer anomalies.

40Ar/39Ar dating, electron microprobe analyses and geologic mapping help clarify chronology and correlations of the numerous volcanic and intrusive units exposed in the area and interpret the petrogenesis of a few of the volcanic units.

Geochemical analysis of rock samples in DBF tables from the PLUTO database. Maps are provided in PDF only.

Maps of aeromagnetic data and a table of gravity station data now available for download

Maps showing aeromagnetic survey results, locations of gravity station data, and discussions of processing within the report

Hand-held magnetometer and sample magnetic susceptibility measurements used to help interpret complex patterns in the magnetic anomaly of this area.

Mathematical modeling, coupled with new observations of magnetic susceptibility, yield better estimates of the underground configuration of granite plutons.

Mathematical modeling and analysis of aeromagnetic anomaly data (gridded data provide in another report).

Provides data for the depth below the land surface,in meters, of the modeled location of the Pre-Tertiary basement surface.

Grid data files along with maps in PDF and PostScript accompany this report

A fault map and digital fault dataset were constructed based on offsets of the basement surface. Because these faults are, in large part, not present at the surface, they are interpreted to be inactive faults, older than the alluvial basin fill.

Magnetic and gravity anomaly and structure contour data

Presents data and describes the methods used to determine the physical attributes, as well as the chemical and mineralogical composition of surficial deposits; groundwater levels; and water composition in this area.

Laboratory reflectance and emissivity spectral measurements of dune sand samples collected from a variety of dune types and mineralogical compositions from eight dune field locations in Alaska, Arizona, California, Colorado, Idaho, Nevada and New Mexico. Data are provided in CSV format.

Gravity measurements used for determining geologic structure to aid in understanding ground-water flow

Aerial, truck-towed, and hand-held magnetometer measurements, gravity station data, and sample density and magnetic susceptibility measures

Gravity and aeromagnetic data analysis described in a report, with a few physical property analyses

Physical property data for selected rock samples accompany these gravity observations

Gravity station data and physical property measurements used to infer subsurface geologic structure

Aeromagnetic survey data giving the calculated magnetic anomaly. Data are provided in CSV format.

Gravity, density, and magnetic susceptibility (for hand samples) measured in this area. Data are provided in CSV format.

Gravity station data, isostatic anomaly map, and depth to basement map derived from geophysical inverse modeling.