Digital compilation and reinterpretation of published and unpublished geologic mapping of Alaska.

Digital compilation and reinterpretation of published and unpublished geologic mapping of Alaska.

Describes the peninsula’s terrane, geologic structure, and map units in detail. The geologic map and stratigraphic terrane correlation chart are included here as PDFs. These are available in a separate report digitally at pubs.usgs.gov/bul/1969b/

For each deposit group, a map indicates relative density and certainty of favorable data. Tables list datasets used in analysis, parameters queried, their contribution to mineral estimates and allow further user analysis. GIS files enable spatial query.

The purpose of this paper is to present new sedimentological, paleontological, and geochemical data that allow us to define the geographic and stratigraphic extent and depositional setting of these temporally unusual phosphorites.

Uninterpreted geophysical measurements and geochemical and mineralogical analytical data from samples collected during the summer field seasons from 2007 to 2010. Data are available in a single Geographic Information System (GIS) database.

Contains results of age dating studies interpreted in other reports. Samples in each study shown as separate sheets within Excel files. Analyses of each zircon are listed separately on a sheet according to filtering scheme and type of instrument used.

This map depicts the fundamental geologic features for the western part of the Fortymile mining district and delineates the location of known bedrock mineral prospects and their relationship to rock types and structural features.

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

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.

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.

Data derived from the 1994 map "Latest Cretaceous and Cenozoic magmatic rocks of Alaska" compiled by E.J. Moll-Stalcup, D.A. Brew, and T.L. Vallier, published (at 1:2,500,000 scale) in volume G-1 of "The Geology of Alaska" (GSA)

Data derived from the 1980 Geologic Map of Alaska compiled by H.M. Beikman and published by the USGS. The map is a regional summary of geologic formations and units at 1:2,500,000 scale. Does not include faults, volcanoes, or correlation chart.

Data derived from the 1996 "Generalized Thermal Maturity Map of Alaska" compiled by M.J. Johnsson and D.G. Howell, published in USGS Bulletin 2142. Combines vitrinite reflectance and conodont alteration index in generalized units.

Radiometric ages of rocks or minerals sampled from Alaska. The data were collected from professional publications and/or received from researchers and used by permission.

A comprehensive database of Alaskan mineral deposits compiled from the published literature and from unpublished reports and data from industry, the US Bureau of Land Management, and USGS.

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.

Basic aeromagnetic data and other airborne survey information for any region of Alaska. Flight-line point information, not grids.

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.

Gridded data from aeroradiometric surveys of Alaska.

Magnetic anomaly expressed in grids with regular spacing derived from 85 separate surveys and provided in several different formats.

This report presents geochemical analyses for 210 unaltered and unmineralized rock samples of Paleozoic age in the western Brooks Range of northern Alaska.

This report presents geochemical analyses for 220 mostly altered and mineralized rock samples from the Red Dog Zn-Pb-Ag district in the western Brooks Range of northern Alaska.

Measurements indicating abundance of radioactive elements in near-surface rocks. Grids and flight-line data from surveys flown 1976-1980.

A surficial geologic map showing the location of the Castle Mountain fault and other active or potentially active faults in the Matanuska-Susitna borough.

Geology of the Christian quadrangle in the Porcupine Plateau, southern Brooks Range, and Yukon Flats. Includes geologic map, fossil data, location of oil shale, and geospatial data sets.

The Castle Mountain fault is a major east-northeast striking fault in southern Alaska with historic seismicity and Holocene surface faulting. This data set is a compilation of fault segments from several publications.

The Bettles quadrangle includes part of the southern Brooks Range and uplands and valleys of interior Alaska. This map depicts the surficial geology and glacial history, and includes description of map units and a correlation of map units.

A 1:250,000 scale surficial geologic map of the Hughes quadrangle, Alaska, which extends into the southern Brooks Range and the uplands and valleys of interior Alaska. The map includes glacial history, geologic unit descriptions, and a correlation of map

Primary surficial units are late Quaternary glacial, glacio-lacustrine, and fluvial deposits. Map and report include radiocarbon dates, geologic units.

Map, report, and geospatial data on the geology of the northeastern part of the 1:250,000 scale Dillingham quadrangle, Alaska. Includes Ar40/39 radiometric ages, geologic unit descriptions, and correlation of map units.

This publication includes a bedrock geologic map depicting the complex allochthonous structure of an area along the north flank of the west-central Brooks Range. A compilation of new and previously reported macro- and micro-fossil identifications and a

Map and report on the surficial deposits and bedrock of the onshore part of the Harrison Bay quadrangle, Alaska. The map area is located within the Arctic Coastal Plain and in the northeastern part of the National Petroleum Reserve of Alaska (NPRA).

Geologic map of the Ikpikpuk quadrangle, compiled from previously published and unpublished sources. This map is part of a collection of digital maps of northern Alaska, that span the transition from the Brooks Range to the Arctic coastal plain.

Geologic map of the Umiat quadrangle, compiled from previously published and unpublished sources. This map is part of a collection of digital maps of northern Alaska, that span the transition from the Brooks Range to the Arctic coastal plain.

Geologic map of the Lookout Ridge quadrangle, compiled from previously published and unpublished sources. This map is part of a collection of digital maps of northern Alaska, that span the transition from the Brooks Range to the Arctic coastal plain.

Geologic map of the Utukok River quadrangle, compiled from previously published and unpublished sources. This map is part of a collection of digital maps of northern Alaska, that span the transition from the Brooks Range to the Arctic coastal plain.

Geologic map of the Point Lay quadrangle, compiled from previously published and unpublished sources. This map is part of a collection of digital maps of northern Alaska, that span the transition from the Brooks Range to the Arctic coastal plain.

Reconnaissance geologic map of the Yukon-Koyukuk basin, Alaska, which is a region characterized by isolated hilly areas and low mountain ranges, separated by broad alluviated interior and coastal lowlands.

Reconnaissance geologic map of the largest National Park in the US. Map area includes high mountains, active and ancient volcanoes, expansive ice fields, and alpine and tidewater glaciers. Kennecott Mine, a world-class copper deposit is located in the p

The Kodiak Islands are located on the west side of the Gulf of Alaska and one of the largest areas of exposure of the flysch and melange of the Chugach terrane of southern Alaska.

Geologic mapping and U-Pb age dating of the Big Delta B-1 quadrangle provides insights into the geology and gold mineralization of the headwater region of the Goodpaster River.

Geologic map of the Big Delta B-2 quadrangle, including U-Pb geochronology, correlation chart, and description of map units.

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 Alaska, with lithology, age, data structure, and format written and arranged just like the other states.

Gravity measured from 1958-2005, with standard gravity reduction calculations applied to correct for latitude, elevation, topography, and isostasy.

Initial results of a petrographic, geochemical, and isotopic study of Mesozoic intrusive rocks and spatially associated Zn-Pb-Ag-Cu-Au prospects in the area.

Geochemical analyses of rocks, mineral separates, bulk samples from lake and stream sediments, heavy mineral concentrates, and soils collected by USGS from 1962 to 2009.

Geochemical analyses of rock, sediment, soil, mineral, and heavy mineral concentrate samples in Alaska analyzed from 1962 through 2009, with best-value estimates.

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.

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.

Location and characteristics of 1,124 individual mineral deposits of this type, with grade and tonnage models for chromium as well as several related elements.

Location and characteristics of 1,124 individual mineral deposits of this type, with grade and tonnage models for chromium as well as several related elements.

Geochemical analyses of rocks, mineral separates, bulk samples from lake and stream sediments, heavy mineral concentrates, and soils collected by USGS from 1962 to 2009.

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.

Georeferenced images depicting the concentration of 68 chemical elements in the near-surface materials (sediments and soils).

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

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.

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.

Descriptions of more than 60 mineral regions, mines, and mineral deposits within the United States and its territories that are reported to contain enrichments of cobalt. Data are provided in Esri file geodatabase, shapefile Microsoft Excel, and CSV formats.

Mean concentrations of 35 elements, ash yields, and pH have been estimated for samples of sils and other unconsolidated surficial materials from 266 collection locations throughout Alaska. These background values can be applied to studies of environmental

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

Weight percent of 15 mineral groups from 331 samples, geochemical analyses of 58 major and trace-element chemical species from 502 samples taken at 175 sites, along with data from geochemical reference standards and analyses of splits.

The Alaska Geochemical Database Version 3.0 (AGDB3) contains new geochemical data compilations in which each geologic material sample has one “best value” determination for each analyzed species, greatly improving speed and efficiency of use. Like the

The Farewell terrane is an exotic continental fragment in interior Alaska that during the early Paleozoic was the site of a passive margin. We report a ²³⁸U/²⁰⁶Pb zircon age of 432.9±3.0 Ma from a Farewell terrane ash in Mt. McKinle

In the past decade, use of hyperspectral imaging (imaging spectroscopy) for mineral exploration and mining operations has been increasing at different spatial scales. In this paper, we focus on recent trends in applying imaging spectrometer data to: 1) ai

Alaska is a major producer of base and precious metals and has a high potential for additional undiscovered mineral resources. However, discovery is hindered by Alaska’s vast size, remoteness, and rugged terrain. New methods are needed to overcome t

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 within Alaska 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.

Analytical results and the evaluated source data files of a geospatial analysis for identifying areas in Alaska that may have potential for hosting mineral deposits of this type.

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.

Explains process by which data on rock type, minerals, geochemistry, and geophysics were analyzed to identify the potential for any lode type of gold deposits in Alaska. Includes descriptive information on the types of lode deposits studied and the results obtained from the analysis.

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. Results are expressed as numerical scores associated with fine-scale watersheds (12-digit hydrologic unit codes).

Explains process by which data on rock type, minerals, geochemistry, and geophysics were analyzed to identify the potential for sediment-hosted lead-zinc deposits in Alaska. Includes descriptive information on the types of deposits studied and the results obtained from the analysis.

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.

Location and characteristics of significant deposits, so designated because they are few in number yet collectively represent almost the totality of domestic production and resources of these metals. Data are provided in Microsoft Excel, Esri file geodatabase, shapefile, and CSV 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.

Major and trace element chemistry of rock samples collected in this area, where surrounding rocks host numerous mineral deposits and occurrences. Data are provided in Microsoft Excel and CSV formats.

Best measured value for 68 elements in 175,856 samples were combined statewide. Data are provided in shapefile format.

Contains one of the largest areas of exposure of the flysch and melange of the Chugach terrane of southern Alaska. This map and its associated digital files were compiled for use at a nominal scale of 1:500,000.

Gridded survey data with summary map images.

Gridded data from aeromagnetic surveys

138 rock geochemistry samples collected during the 2006 field season were analyzed using the ICP-AES/MS42, ICP-AES10, fire assay, and cold vapor atomic absorption methods

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

Analyses of 72 water samples include pH, conductivity, water temperature, major cation and anion concentrations, trace-element concentrations, and dissolved organic-carbon concentrations.

Measurements on 92 samples, including pH, conductivity, water temperature, major cation and anion concentrations, and trace-element concentrations.

Geospatial data sets of the geology of the Alaska Peninsula, Alaska, including a geologic map and complete unit descriptions.

Analytical results for geochemical samples collected in 2007 from the Pebble deposit and surrounding environs

Chemical analysis of surface samples taken over a well known but concealed deposit to understand metal migration into the surface materials and to assess the power of surface sampling for detecting concealed deposits of this type.

Electron microprobe geochemical data that is used to showcase differences in phosphates when derived from magmatic-hydrothermal systems compared to metamorphic-hydrothermal systems to improve understanding of the mechanisms by which some mineral deposits were formed. Data are provide in CSV format.

Flight-line data from the aeromagnetic survey

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

This map covers the Eagle 1:250,000-scale quadrangle in the northeastern part of the Yukon-Tanana Upland in Alaska. It shows the extent of five major glacial advances, former glacial lakes, and present fragmented terrace deposits related to the advances.

Study to estimate the 3-D distribution of permafrost, to evaluate the effectiveness of these methods at mapping permafrost geometry, and to better define the physical properties of the subsurface in discontinuous permafrost areas.

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.

Includes all geochemical data generated by each project partnership funded through Earth MRI and will be updated periodically as additional geochemical data from these projects becomes available.

Airborne electromagnetic and magnetic survey data were collected during 2016 along 300 line kilometers in this area, flown at a nominal flight height of 30 m above terrain along widely spaced reconnaissance lines. Includes raw and processed AEM data, laterally-constrained inverted resistivity depth sections along all flight lines, and unprocessed and processed magnetic data. Data are provided in CSV format.

A compilation and statistical analysis of 306 density and 706 magnetic susceptibility measurements of rocks from south-central Alaska

Data collected as part of a geological and geophysical framework study

Analysis of rock samples, with photos of sample localities

New gravity stations combined here with older measurements taken by other USGS survey trips

Chemical analysis of 201 samples of rocks thought to be altered or mineralized in an area containing numerous mines.

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

Report containing tables of geochemical data

Map at 1:63,360 scale shows the bedrock geology of a special study area within the Chugach National Forest, Alaska. Includes ARC/Info export files and graphics.

Geologic map compiled from existing sources without generalization, with new or revised data where available. Part of a statewide geologic map database effort in which the structure and content of the data is as consistent as is practical.

Reflectance, mineral predominance, and white mica wavelength position data calculated from an airborne hyperspectral imaging survey of this area using a HyMap sensor in 2014. Data are provided in a format generated by the ENVI software product, CSV, and GeoTiff.

Hyperspectral analysis of rock samples using this equipment provide information on the composition and morphology of the minerals in the rock in microscopic detail. Data are provided as imagery in various formats.

Flight-line data for a hyperspectral survey using the HyMap sensor over this area in 2014 where porphyry deposits are exposed. The data are provided in imagery formats.

Geochemical, x-ray diffraction mineralogical, and electron probe microanalysis (EPMA) data on rocks, soils, and sediments collected near porphyry copper deposits in this area. Data are provided in CSV format.

Major element oxide and trace element geochemical analyses, including those for gold, silver, and base metals, for representative rock units and for grab samples from quartz veins and mineralized zones within the quadrangle

Geochemical data for stream sediment, surface-water, rock, precipitate, and vegetation samples from Red Mountain

Results of mineral abundance estimates based on Rietveld refinement of X-ray diffraction (XRD) analyses of mill tailings and other ore processing materials from worldwide localities. Data are provided in CSV format.

This large producer of mercury operated from 1933 to 1971. As part of remediation work, this survey used electromagnetic methods to study subsurface resistivity.

Redigitized and corrected data from a previously published study

Geophysical modeling used to study mineral deposit geometry. Includes 227 new gravity stations.

Updated bedrock geologic mapping of the area incorporating a recent airborne geophysical survey, new field work, fossils, radiometric ages, and geochemical signatures. Includes GIS data.

Small regional scale geochemical mineral exploration results from field studies in Duncan Canal, Zarembo Island, and western Etolin Island.

A simplified geologic map, raw gravity and magnetic data, with derivative products including depth-to-source and rock densities, with limited interpretations of the underlying geology, structures, and mineral resources.

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

Samples of surficial materials analyzed for aluminum, barium, cadmium, lead, and zinc concentrations.

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.

This metal ore deposit formed over a period of time in which its tectonic setting was changing, consequently it shows a range of characteristics typical of several different types of deposits. Rock geochemistry data are provided in tabular form.