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Minerals & deposits

Find USGS publications on mineral resources and deposits. Search commodities and geographic names, then check source reports for geology and assessment methods.

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At least 181 records · Page 10Linked to original sources

USGS1982

The Alaska Mineral Resource Assessment Program: Guide to information about the geology and mineral resources of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska

The Ketchikan and Prince Rupert 1-degree by 2-degree quadrangles, which encompass about 16,000 km2 at the south tip of southeastern Alaska, have been investigated by integrated field and laboratory studies in the disciplines of geology, geochemistry, geophysics, and Landsat data interpretation to determine their mineral-resource potential. Mineral deposits in the study area have been mined or prospected intermittently since about 1900, and production of small tonnages of ores containing gold, silver, copper, lead, zinc, and tungsten has been recorded. Extensive exploration and development currently (1981) is underway at a molybdenum prospect about 65 km east of Ketchikan. Our mineral-resource assessment indicates that the area contains potentially significant amounts of those metallic commodities, as well as of molybdenum, iron, antimony, and barite. The results of these studies have been published in a folio of maps accompanied by descriptive texts, diagrams, tables, and pertinent references. The present report serves as a guide to these investigations, provides relevant background information, and integrates the component maps and reports. It also describes revisions to the geology based on studies completed since the folio was published and includes a list of specific and general references on the geology and mineral deposits of the study area.

Alaska↗

USGS2005

Questa baseline and pre-mining ground-water quality invistigation. 13. Mineral microscopy and chemistry of mined and unmined porphyry molybdenum mineralization along the Red River, New Mexico: Implications for ground- and surface-water quality

This report is one in a series presenting results of an interdisciplinary U.S. Geological Survey (USGS) study of ground-water quality in the lower Red River watershed prior to open-pit and underground molybdenite mining at Molycorp's Questa mine. The stretch of the Red River watershed that extends from just upstream of the town of Red River to just above the town of Questa includes several mineralized areas in addition to the one mined by Molycorp. Natural erosion and weathering of pyrite-rich rocks in the mineralized areas has created a series of erosional scars along this stretch of the Red River that contribute acidic waters, as well as mineralized alluvial material and sediments, to the river. The overall goal of the USGS study is to infer the pre-mining ground-water quality at the Molycorp mine site. An integrated geologic, hydrologic, and geochemical model for ground water in the mineralized but unmined Straight Creek drainage is being used as an analogue for the geologic, geochemical, and hydrologic conditions that influenced ground-water quality and quantity at the mine site prior to mining. This report summarizes results of reconnaissance mineralogical and chemical characterization studies of rock samples collected from the various scars and the Molycorp open pit, and of drill cuttings or drill core from bedrock beneath the scars and adjacent debris fans.

New Mexico↗

USGS2013

U.S. mineral dependence—Statistical compilation of U.S. and world mineral production, consumption, and trade, 1990–2010

This report provides insight into the dependence of the United States on foreign supply to meet the country’s mineral needs. When determining vulnerabilities to the U.S. supply, it is not enough to look solely at the mining source for each mineral to determine the potential impact that a supply disruption might have on the Nation’s economy. The tables that accompany this report help to illustrate the importance not only of the mining and processing of minerals but also the exporting countries and end uses. Understanding the total risks and costs of supply disruptions along the supply chain are beyond the scope of this report. However, this overview of mineral production, consumption, and trade highlights the importance of understanding what is happening at each point along the supply chain.

Open-File Report↗

USGS2018

Titanium mineral resources in heavy-mineral sands in the Atlantic coastal plain of the southeastern United States

This study examined titanium distribution in the Atlantic Coastal Plain of the southeastern United States; the titanium is found in heavy-mineral sands that include the minerals ilmenite (Fe 2+ TiO 3 ), rutile (TiO 2 ), or leucoxene (an alteration product of ilmenite). Deposits of heavy-mineral sands in ancient and modern coastal plains are a significant feedstock source for the titanium dioxide pigments industry. Currently, two heavy-mineral sands mining and processing operations are active in the southeast United States producing concentrates of ilmenite-leucoxene, rutile, and zircon. The results of this study indicate the potential for similar deposits in many areas of the Atlantic Coastal Plain. This study used the titanium analyses of 3,457 stream sediment samples that were analyzed as part of the U.S. Geological Survey’s National Geochemical Survey program. This data set was analyzed by an integrated spatial modeling technique known as Bayesian hierarchical modeling to map the regional-scale, spatial distribution of titanium concentrations. In particular, clusters of anomalous concentrations of titanium occur: (1) along the Fall Zone, from Virginia to Alabama, where metamorphic and igneous rocks of the Piedmont region contact younger sediments of the Coastal Plain; (2) a paleovalley near the South Carolina and North Carolina border; (3) the upper and middle Atlantic Coastal Plain of North Carolina; (4) the majority of the Atlantic Coastal Plain of Virginia; and (5) barrier islands and stretches of the modern shoreline from South Carolina to northeast Florida. The areas mapped by this study could help mining companies delimit areas for exploration.

Scientific Investigations Report↗

USGS2006

Effects of Chinese mineral strategies on the U.S. minerals industry

For more than two decades now, China has been undergoing rapid economic growth and industrialization. The industrialization and urbanization of the once rural, farming nation is leading to increased consumption of mineral commodities to build infrastructure and to make into consumer goods. This increased consumption has led to higher mineral prices, lower stocks and, in some cases, temporary shortages of minerals. Chinese mineral producers and manufacturers are responding by building capacity, restructuring and modernizing industrial sectors and establishing international network that compete with those of the United States and other nations.

Mining Engineering↗

USGS2006

Structural fabrics, mineralization and Lamaride kinematics of the Idaho Springs-Ralston shear zone, Colorado mineral belt and central Front Range uplift

The Idaho Springs and Central City mining districts form the central portion of a structurally controlled hydrothermal precious- and base-metal vein system in the Front Range of the northeast-trending Colorado Mineral Belt. Three new 40Ar/39Ar plateau ages on hydrothermal sericite indicate the veins formed during the Laramide orogeny between 65.4??1.5 - 61.9??1.3 Ma. We compile structural geologic data from surface geological maps, subsurface mine maps, and theses for analysis using modern graphical methods and integration into models of formation of economic mineral deposits. Structural data sets, produced in the 1950s and 1960s by the U.S. Geological Survey, are compiled for fabric elements, including metamorphic foliations, fold axial trends, major brittle fault zones, quartz and precious- and base-metal veins and fault veins, Tertiary dikes, and joints. These fabric elements are plotted on equal-area projections and analyzed for mean fabric orientations. Strike-slip fault-vein sets are mostly parallel or sub-parallel, and not conjugate as interpreted by previous work; late-stage, normal-slip fault veins possibly show a pattern indicative of triaxial strain. Fault-slip kinematic analysis was used to model the trend of the Laramide maximum horizontal stress axis, or compression direction, and to determine compatibility of opening and shear motions within a single stress field. The combined-model maximum compression direction for all strike slip fault veins is ???068??, which is consistent with published Laramide compression directions of ???064?? (mean of 23 regional models) and ???072?? for the Front Range uplift. The orientations of fabric elements were analyzed for mechanical and kinematic compatibility with opening, and thus permeability enhancement, in the modeled regional east-northeast, Laramide compression direction. The fabric orientation analysis and paleostress modeling show that structural permeability during mineralization was enhanced along pre-existing metamorphic foliations and fold axial planes. Large orientation dispersion in most fabric elements likely caused myriad potential pathways for permeability. The dominant orientations of opening and shear mode structures are consistent with a sub-parallel network of structures that formed in the Laramide east-northeast compression direction. The results presented demonstrate the importance of using mechanical and kinematic theory integrated with contemporary ideas of permeability structure to better understand the coupled nature of fluid flow, mineral deposition, stress, and strain. Further, the results demonstrate that there is significant internal strain within this basement-cored uplift that was localized by optimally oriented pre-existing structures in a regional stress field.

Mountain Geologist↗

USGS2021

Mineral deposits of the Mesoproterozoic Midcontinent Rift System in the Lake Superior region – Metallogeny of the prolifically mineralized Keweenawan LIP

The Keweenawan large igneous province (LIP) of the Midcontinent Rift System (MRS) of North America is perhaps the most prolifically and diversely mineralized LIP known on Earth (Nicholson et al., 1992). The MRS is an approximately 2,200 km curvilinear continental rift that stretches from Kansas northeast to the Lake Superior region where it turns southeast and extends through lower Michigan (Fig. 1). Rocks of the MRS host a varied suite of magmatic and hydrothermal mineral deposits in the Lake Superior region of the United States and Canada where rift rocks are exposed at or near the surface. Historically, hydrothermal deposits, such as Michigan’s native Cu deposits and the White Pine sediment-hosted stratiform Cu deposit, were major MRS metal producers. On-going exploration for and potential development of Cu-Ni sulfide deposits hosted by the Duluth Complex of Minnesota and the opening of the Eagle Ni mine in Michigan indicate an expanding interest in MRS magmatic deposits. Many of the MRS hydrothermal and magmatic mineral deposits are significant past, present, and likely future providers of critical minerals. We have placed these deposits into a space and time metallogenic framework (Woodruff et al., 2020a) that is summarized here.

Iowa, Kansas, Minnesota, Michigan, Nebraska, Ontar↗

USGS1995

Petrography and mineral chemistry of the composite Deboullie Pluton, northern Maine, USA: implications for the genesis of Cu-Mo mineralization

Biotite and apatite mineral chemistry, particularly halogen abundances and ratios, are used to investigate the relation of the two contrasting parts of the Deboullie composite pluton (syenite-granodiorite) located in northern Maine. Biotite mineral chemistry helps to classify the weakly developed porphyry-style mineralization (Cu-Mo) associated with syenitic rocks of the Deboullie pluton. Biotite and apatite occur within the matrix of the rocks and within small multiphase inclusions hosted by clinopyroxene. The inclusions are interpreted to be crystallized melt inclusions rather than solid inclusions, that were trapped by clinopyroxene during growth. The multiphase inclusions consist of K-feldspar + quartz + biotite + apatite + magnetite. On a regional scale, biotite compositions from granitic plutons in Maine do not vary in a systematic manner. -from Authors

Chemical Geology↗

USGS1995

Industrial minerals of the Midcontinent: Proceedings of the Midcontinent industrial minerals workshop

The Midcontinent Industrial Minerals Workshop, in St. Louis, Missouri, September 16-17, 1991, was the fourth U.S. Geological Survey-sponsored meeting on the essential role of industrial rocks and minerals in the Nation's social and economic framework. The meeting was organized, supported, and the agenda was determined by a group from the USGS, the U.S. Bureau of Mines, and the State geological surveys of Arkansas, Illinois, Kansas, Kentucky, Missouri, Nebraska, and Oklahoma, with early assistance in planning from the Iowa and Tennessee surveys. As the major industrial rocks and minerals used in the nine-State area of the Midcontinent are construction materials, the Workshop focused on sand and gravel and limestone-dolomite resources and the extraction industry for those materials. Because active audience participation was considered vital, representatives from industry, universities, geological surveys, planning groups, regulatory agencies, and State legislatures were invited. The audience consisted of 87 attendees out of 120 invited participants (no legislators attended).

Bulletin↗

USGS1977

The Alaskan Mineral Resource Assessment Program; background information to accompany folio of geologic and mineral resource maps of the McCarthy Quadrangle, Alaska

The McCarthy 1? by 3? quadrangle, in eastern south-central Alaska, contains potentially significant resources of copper and possibly of a few other commodities. This circular and a companion folio of maps represent results of integrated field and laboratory studies in the disciplines of geology, geophysics, geochemistry, and satellite imagery that are designed to provide a modern mineral resource assessment of the quadrangle. The maps are accompanied by descriptive texts, explanatory material, pertinent references, and by a few auxiliary tables and diagrams. This circular provides background information for the mineral resource assessment and integrates the component maps. It also includes a master list of references (see 'Bibliography') relevant to the geology and mineral deposits of the quadrangle.

Circular↗

USGS1984

The Alaskan Mineral Resource Assessment Program: Guide to information contained in the folio of geologic and mineral-resource maps of the Medfra quadrangle, Alaska

The Medfra quadrangle in west-central Alaska was investigated by a multidisciplinary team of geoscientists to assess its mineral resources. This Circular is intended to serve as a guide to a folio of 13 separate Open-File Reports covering various aspects of these investigations, including geology, bedrock and stream-sediment geochemistry, potassium-argon dating, Landsat imagery, mineral occurrences, aeromagnetic interpretation, and mineral-resource assessment. This Circular presents a complete reference list of these reports and a summary of the important results of each of the investigations.

Alaska↗

USGS2013

Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the Dudkash mineral district in Afghanistan: Chapter R in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan

The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the areas and (2) provide useful information to private investors who are considering investment in a particular area for development of its natural resources. The set of satellite-image mosaics provided in this Data Series (DS) is one such database. Although airborne digital color-infrared imagery was acquired for parts of Afghanistan in 2006, the image data have radiometric variations that preclude their use in creating a consistent image mosaic for geologic analysis. Consequently, image mosaics were created using ALOS (Advanced Land Observation Satellite; renamed Daichi) satellite images, whose radiometry has been well determined (Saunier, 2007a,b). This part of the DS consists of the locally enhanced ALOS image mosaics for the Dudkash mineral district, which has industrial mineral deposits. ALOS was launched on January 24, 2006, and provides multispectral images from the AVNIR (Advanced Visible and Near-Infrared Radiometer) sensor in blue (420–500 nanometer, nm), green (520–600 nm), red (610–690 nm), and near-infrared (760–890 nm) wavelength bands with an 8-bit dynamic range and a 10-meter (m) ground resolution. The satellite also provides a panchromatic band image from the PRISM (Panchromatic Remote-sensing Instrument for Stereo Mapping) sensor (520–770 nm) with the same dynamic range but a 2.5-m ground resolution. The image products in this DS incorporate copyrighted data provided by the Japan Aerospace Exploration Agency (©JAXA,2006,2007,2008,2009), but the image processing has altered the original pixel structure and all image values of the JAXA ALOS data, such that original image values cannot be recreated from this DS. As such, the DS products match JAXA criteria for value added products, which are not copyrighted, according to the ALOS end-user license agreement. The selection criteria for the satellite imagery used in our mosaics were images having (1) the highest solar-elevation angles (near summer solstice) and (2) the least cloud, cloud-shadow, and snow cover. The multispectral and panchromatic data were orthorectified with ALOS satellite ephemeris data, a process which is not as accurate as orthorectification using digital elevation models (DEMs); however, the ALOS processing center did not have a precise DEM. As a result, the multispectral and panchromatic image pairs were generally not well registered to the surface and not coregistered well enough to perform resolution enhancement on the multispectral data. For this particular area, PRISM image orthorectification was performed by the Alaska Satellite Facility, applying its photogrammetric software to PRISM stereo images with vertical control points obtained from the digital elevation database produced by the Shuttle Radar Topography Mission (Farr and others, 2007) and horizontal adjustments based on a controlled Landsat image base (Davis, 2006). The 10-m AVNIR multispectral imagery was then coregistered to the orthorectified PRISM images and individual multispectral and panchromatic images were mosaicked into single images of the entire area of interest. The image coregistration was facilitated using an automated control-point algorithm developed by the USGS that allows image coregistration to within one picture element. Before rectification, the multispectral and panchromatic images were converted to radiance values and then to relative-reflectance values using the methods described in Davis (2006). Mosaicking the multispectral or panchromatic images started with the image with the highest sun-elevation angle and the least atmospheric scattering, which was treated as the standard image. The band-reflectance values of all other multispectral or panchromatic images within the area were sequentially adjusted to that of the standard image by determining band-reflectance correspondence between overlapping images using linear least-squares analysis. The resolution of the multispectral image mosaic was then increased to that of the panchromatic image mosaic using the SPARKLE logic, which is described in Davis (2006). Each of the four-band images within the resolution-enhanced image mosaic was individually subjected to a local-area histogram stretch algorithm (described in Davis, 2007), which stretches each band’s picture element based on the digital values of all picture elements within a 500-m radius. The final databases, which are provided in this DS, are three-band, color-composite images of the local-area-enhanced, natural-color data (the blue, green, and red wavelength bands) and color-infrared data (the green, red, and near-infrared wavelength bands). All image data were initially projected and maintained in Universal Transverse Mercator (UTM) map projection using the target area’s local zone (42 for Dudkash) and the WGS84 datum. The final image mosaics were subdivided into eight overlapping tiles or quadrants because of the large size of the target area. The eight image tiles (or quadrants) for the Dudkash area are provided as embedded geotiff images, which can be read and used by most geographic information system (GIS) and image-processing software. The tiff world files (tfw) are provided, even though they are generally not needed for most software to read an embedded geotiff image.

Dudkash Mineral District↗

USGS2011

Summaries of important areas for mineral investment and production opportunities of nonfuel minerals in Afghanistan

The U.S. Geological Survey (USGS) and the U.S. Department of Defense Task Force for Business and Stability Operations (TFBSO) entered into an agreement with the Afghanistan Geological Survey to study and assess the fuel and nonfuel mineral resources of Afghanistan from October 2009 to September 2011 so that these resources could be economically extracted to expand the economy of Afghanistan. This report summarizes the results of joint studies on 24 important areas of interest (AOIs) of nonfuel mineral resources that were identified for mineral investment and production opportunities in Afghanistan. This report is supported by digital data and archival and non-USGS reports on each AOI, and these data are available from the Afghanistan Geological Survey Data Center in Kabul (http://mom.gov.af/en/ and http://www.bgs.ac.uk/afghanminerals/) and for viewing and download on the USGS public Web site and in a separate viewer at http://mapdss2.er.usgs.gov/.

Open-File Report↗

USGS1975

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Bendeleben Quadrangle, Alaska

This summary of references is designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in the Bendeleben quadrangle, Alaska. All references to published and open-filed reports of the Geological Survey, to most published and open-filed reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975, are summarized. Certain, mainly statistical, reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This summary is divided into three parts: a section made up of summaries of references arranged alphabetically by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section and cited in introductory paragraphs. Pages are not numbered because users may wish to add data from other sources.

Alaska↗

USGS1975

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Teller Quadrangle, Alaska

This summary of references is designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in the Teller quadrangle, Alaska. All references to published and open-filed reports of the Geological Survey, to most published and open-filed reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975, are summarized. Certain, mainly statistical, reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Gedlogical and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This summary is divided into three parts: a section made up of summaries of references arranged alphabetically by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section and cited in introductory paragraphs. Pages are not numbered because users may wish to add data from other sources.

Alaska↗

USGS1975

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in five quadrangles in West-Central Alaska (Hughes, Kotzebue, Melozitna, Selawik, Shungnak)

These summaries of references are designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in 5 quadrangles in west-central Alaska. All references to published and open-filed reports of the Geological Survey, to most published and open-filed reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975, are summarized. Occasionally reports from other sources have been included; in such instances references have been summarized in greater detail than those to the kinds of reports listed above. Certain, mainly statistical, reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This report is divided into three parts: a section made up of summaries of references arranged alphabetically first by quadrangle and second by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section.

Alaska↗

USGS1975

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in Northern Alaska

These summaries of references are designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in 11 quadrangles in northern Alaska. All references to published and open-filed reports of the Geological Survey, to most published and open-filed reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975. are summarized. Occasionally reports from other sources have been included; in such instances references have been summarized in greater detail than those to the kinds of reports listed above. Certain, mainly statistical reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This report is divided into three parts: a section made up of summaries of references arranged alphabetically first by quadrangle and second by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section.

Alaska↗

USGS1976

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Chandalar and Wiseman quadrangles, Alaska

These summaries of references are designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in the Chandalar and Wiseman quadrangles in the southern Brooks Range, Alaska. All references to reports of the Geological Survey, to most reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975, are summarized. An unpublished manuscript report of the Alaska Territorial Department of Mines (Reed, 1938) is included; references to it are summarized in greater detail than those to the kinds of reports listed above. Certain, mainly statistical, reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This report is divided into three parts: a section made up of summaries of references arranged alphabetically first by quadrangle and second by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section.

Alaska↗