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Limestone - A Crucial and Versatile Industrial Mineral Commodity

Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Although limestone is common in many parts of the United States, it is critically absent from some. Limestone is used to produce Portland cement, as aggregate in concrete and asphalt, and in an enormous array of other products, making it a truly versatile commodity. Portland cement is essential to the building industry, but despite our Nation's abundance of limestone, there have been cement shortages in recent years. These have been caused in part by a need to find new areas suitable for quarrying operations. To help manage our Nation's resources of such essential mineral commodities, the U.S. Geological Survey (USGS) provides crucial data and scientific information to industry, policymakers, and the public.

Fact Sheet↗

A Crosswalk of Mineral Commodity End Uses and North American Industry Classification System (NAICS) codes

This crosswalk is based on the premise that there is a connection between the way mineral commodities are used and how this use is reflected in the economy. Raw mineral commodities are the basic materials from which goods, finished products, or intermediate materials are manufactured or made. Mineral commodities are vital to the development of the U.S. economy and they impact nearly every industrial segment of the economy, representing 12.2 percent of the U.S. gross domestic product (GDP) in 2010 (U.S. Bureau of Economic Analysis, 2014). In an effort to better understand the distribution of mineral commodities in the economy, the U.S. Geological Survey (USGS) attempts to link the end uses of mineral commodities to the corresponding North American Industry Classification System (NAICS) codes. The links between the end uses of mineral commodities and the NAICS codes provide an instrument for analyzing the use of mineral commodities in the economy. The crosswalk is also a guide, highlighting those industrial sectors in the economy that rely heavily on mineral commodities. The distribution of mineral commodities across the economy is dynamic and does differ from year to year. This report reflects a snapshot of the state of the economy and mineral commodities in 2010.

Open-File Report↗

Geomedia: Mapping Colorado at a fine scale

Currently, only 24 percent of Colorado's spectacular geology has been mapped at the fine scale of 1:24,000. At the same time, the state hosts many geologic hazards. Most maps of Colorado are at much broader scales, failing to show detail of basic geology crucial to safe engineering and building practices in a state that had the third-fastest-growing population during the 1990s. And the 2000 Census showed that the state, despite some economic woes, remains one of the fastest growing. Detailed geologic maps also aid the mineral industries that help fuel such growth. Since 1992, the Colorado Geological Survey (CGS) has mapped 1:24,000-scale quadrangles in high-impact areas under the STATEMAP component of the National Cooperative Geologic Mapping Program. In 2002, CGS completed its 43rd geologic quadrangle map. The long-range plan for the state is to complete 116 high-priority quadrangles in the next 15 years. The survey's approach is to select rapidly growing areas with relatively high potential for hazards and map contiguous quadrangles. In addition to mapping bedrock, CGS geologists have mapped the Quaternary deposits at the surface. Understanding these deposits is extremely important for implementing sound engineering practices because of potential for subsidence and landslides. The CGS mapping has not only yielded information about potential hazards, but also advanced scientific understanding of the state.

Geotimes↗

Maps showing industrial mineral resources of the Joplin 1° x 2° quadrangle, Kansas and Missouri

This map is part of a folio of maps of the Joplin 1° X 2° quadrangle, Kansas and Missouri prepared under the Conterminuous United States Mineral Assessment Program (CUSMAP). Other publications in this folio to date include U.S. Geological Survey Miscellaneous Field Studies Map MF-2125-A (Erickson and others, 1990). Additional maps showing various geologic aspects of the Joplin quadrangle will be published as U.S. Geological Survey Miscellaneous Field Studies Maps bearing this same serial number with different letter suffixes (MF-2125-C, -D, and so on). The industrial mineral resources of the Joplin 1° X 2° quadrangle are crushed stone, dimension stone, clay and shale, construction sand and gravel (including chat, or chert-rich tailings from metal mines), and asphaltic sandstone. At present only crushed stone, clay and shale, and construction sand and gravel are of economic importance; the remainder are considered hypothetical resources. The value of industrial mineral production during 1987, the most recent year of complete data as supplied by the U.S. Bureau of Mines, was nearly $25,600,000. In terms of finished products such as cement and brick, the value is several times that amount. Figure 1 shows the annual value of industrial mineral production within the quadrangle from 1960 through 1987.

Kansas;Missouri↗

Historical files from Federal Government mineral exploration-assistance programs, 1950 to 1974

The Defense Minerals Administration (DMA), Defense Minerals Exploration Administration (DMEA), and Office of Minerals Exploration (OME) mineral exploration programs were active over the period 1950–1974. Under these programs, the Federal Government contributed financial assistance in the exploration for certain strategic and critical minerals. The information about a mining property that was collected under these programs was placed in files called dockets. A docket is a collection of material (application, contract, correspondence, maps, reports, results) about a property for which an individual applied for exploration assistance from the Federal Government. Information found in dockets describe where mineral deposits were examined, what was found, and whether it was mined. As such, they provide very useful information to private industry regarding potential and non-potential prospect areas, provide the U.S. Geological Survey with useful information on mineral occurrences that are used in national assessments for particular mineral deposits, and provide other U.S. Federal agencies (Bureau of Indian Affairs, Bureau of Land Management, and Environmental Protection Agency) information relevant to land management, permitting, and leasing.

Data Series↗

High-resolution digital elevation dataset for Crater Lake National Park and vicinity, Oregon, based on LiDAR survey of August-September 2010 and bathymetric survey of July 2000

Crater Lake partially fills the caldera that formed approximately 7,700 years ago during the eruption of a 12,000-foot volcano known as Mount Mazama. The caldera-forming or climactic eruption of Mount Mazama devastated the surrounding landscape, left a thick deposit of pumice and ash in adjacent valleys, and spread a blanket of volcanic ash as far away as southern Canada. Because the Crater Lake region is potentially volcanically active, knowledge of past events is important to understanding hazards from future eruptions. Similarly, because the area is seismically active, documenting and evaluating geologic faults is critical to assessing hazards from earthquakes. As part of the American Recovery and Reinvestment Act (ARRA) of 2009, the U.S. Geological Survey was awarded funding for high-precision airborne LiDAR ( Li ght D etection A nd R anging) data collection at several volcanoes in the Cascade Range through the Oregon LiDAR Consortium, administered by the Oregon Department of Geology and Mineral Industries (DOGAMI). The Oregon LiDAR Consortium contracted with Watershed Sciences, Inc., to conduct the data collection surveys. Collaborating agencies participating with the Oregon LiDAR Consortium for data collection in the Crater Lake region include Crater Lake National Park (National Park Service) and the Federal Highway Administration. In the immediate vicinity of Crater Lake National Park, 798 square kilometers of LiDAR data were collected, providing a digital elevation dataset of the ground surface beneath forest cover with an average resolution of 1.6 laser returns/m 2 and both vertical and horizontal accuracies of ±5 cm. The LiDAR data were mosaicked in this report with bathymetry of the lake floor of Crater Lake, collected in 2000 using high-resolution multibeam sonar in a collaborative effort between the U.S. Geological Survey, Crater Lake National Park, and the Center for Coastal and Ocean Mapping at the University of New Hampshire. The bathymetric survey collected 16 million soundings with a spatial resolution of 2 meters using an EM1002 system owned and operated by C&C Technologies, Inc. The combined LiDAR and bathymetric dataset has a cell size of 1 meter and will contribute to understanding past volcanic events and their deposits, recognizing of faults and volcanic landforms, and quantifying landscape modification during and after the next volcanic eruption at Crater Lake.

Oregon↗

Annual review 2016: Exploration review

This summary of international mineral exploration activities for the year 2016 draws upon information from industry sources, published literature, SNL Metals & Mining (SNL), an offering of S&P Global Market Intelligence (New York, NY), and specialists in the U.S. Geological Survey (USGS) National Minerals Information Center. Three types of information are reported and analyzed in this annual review of international exploration: 1) budgetary statistics expressed in U.S. dollars provided by SNL; 2) regional and site-specific exploration activities that took place in 2016 as compiled by the USGS and 3) regional events and legislation that affected exploration activities including economic, social and political conditions, which were derived from published sources and discussions with USGS and industry specialists. Commodity and regional compilations are presented in this summary. Because multiple sources were used to develop commodity and regional compilations, statistics may vary depending on the source and type of data that are being reported.

Mining Engineering↗

Porphyry copper assessment of British Columbia and Yukon Territory, Canada: Chapter C in Global mineral resource assessment

The U.S. Geological Survey does regional, national, and global assessments of resources (mineral, energy, water, biologic) to provide science in support of land management and decision making. Mineral resource assessments provide a synthesis of available information about where mineral deposits are known and suspected to be in the Earth’s crust, which commodities may be present, and estimates of amounts of resources that may be present in undiscovered deposits. Canada is an important source of copper, consistently ranking as one of the top 10 world producers during the past decade (2000–2010). The preponderance of this production has been from porphyry-copper-type deposits in the western Canadian Cordillera. A probabilistic mineral resource assessment of undiscovered resources associated with porphyry copper deposits in western Canada was completed as part of a global mineral resource assessment. The purpose of the assessment was to (1) compile a database of known deposits and significant prospects, (2) delineate permissive areas (tracts) for undiscovered porphyry copper deposits that may be present in the upper kilometer (minimally) of the Earth’s crust, and (3) provide probabilistic estimates of amounts of copper (Cu), molybdenum (Mo), gold (Au), and silver (Ag) that could be contained in undiscovered porphyry copper deposits in the tracts. The study was done by the U.S. Geological Survey (USGS) in collaboration with geologists from the British Columbia Geological Survey, Yukon Geological Survey, and industry consultants. The database of known deposits and significant prospects includes an inventory of mineral resources in 89 known porphyry copper (and 2 related copper-bearing polymetallic vein) ore zones, representing 50 porphyry copper deposits, and lists key characteristics of 280 additional porphyry copper and related copper-bearing prospects, as indicated by currently available exploration results, which also are summarized. Resource and exploration and development activity are updated with information current through April 2010. The delineation of permissive tracts and probabilistic estimation of resources in undiscovered deposits were done using the USGS three-part mineral resource assessment approach. Permissive tracts are defined in accordance with descriptive models for porphyry copper deposits to include igneous rocks and known deposits and prospects within magmatic arcs related to convergent plate-margin boundary zones. Frequency distributions of total tonnages and average grades of thoroughly explored deposits were used as models for undiscovered deposits and include a new grade and tonnage model for calc-alkaline porphyry Cu±Mo±Au deposits in western Canada. Five permissive tracts for the occurrence of porphyry copper deposits were delineated: 2 island-arc tracts, 1 tract of transitional, mixed island-arc and continental arc affinities, and 2 continental arc tracts. In permissive tract 003pCu2001, calc-alkaline igneous rocks of Middle Triassic to Late Jurassic age in accreted island-arc terranes of the Intermontane belt are assessed for calc-alkaline porphyry Cu±Mo±Au deposits. The area of this tract is 175,250 km 2 . In 12 known deposits, the total reported tonnage of ore is 8,100 million metric tons (Mt) containing 24.6 Mt copper. An estimated 6.9 undiscovered deposits contain a calculated mean of 8.9 Mt copper and a median of 6.9 Mt copper. The spatial density for the 18.9 known plus estimated undiscovered deposits in this tract is approximately 11 deposits per 100,000 km 2 . In permissive tract 003pCu2002, alkaline igneous rocks of Middle Triassic to Late Jurassic age within the Intermontane accreted island-arc terranes are assessed for alkaline porphyry Cu-Au deposits. The area of this tract is 109,290 km 2 . In 12 known deposits the total reported tonnage of ore is 6,440 Mt, containing 20.9 Mt copper. An estimated 7 undiscovered deposits contain a calculated mean of 22 Mt copper and a median of 13 Mt copper. The spatial density for the 19 known plus estimated undiscovered deposits in this tract is approximately 17 deposits per 100,000 km 2 . In permissive tract 003pCu2003, calc-alkaline igneous rocks of Late Triassic to Early Cretaceous age within the accreted Insular terranes of mixed island-arc and continental arc affinities are assessed for calc-alkaline porphyry Cu±Mo±Au deposits. The area of this tract is 58,360 km 2 . The total tonnage of ore reported in the 2 known deposits is 1,160 Mt containing 3.17 Mt copper. An estimated 2.3 undiscovered deposits contain a calculated mean of 3 Mt copper and a median of 1.9 Mt copper. The spatial density for the 4.3 known plus estimated undiscovered deposits in this tract is approximately 7 deposits per 100,000 km 2 . In permissive tract 003pCu2004, calc-alkaline igneous rocks in continental magmatic arcs of Jurassic to Eocene age are assessed for porphyry Cu±Mo±Au deposits. The area of this tract is 639,500 km 2 . The total tonnage of ore reported for the 23 known deposits is 6,520 Mt containing 17.9 Mt copper. An estimated 9.6 undiscovered deposits contain a calculated mean of 13 Mt copper and a median of 11 Mt copper. The spatial density for the 32.6 known deposits plus the estimated undiscovered deposits in this tract is approximately 5 deposits per 100,000 km 2 . In permissive tract 003pCu2005, calc-alkaline igneous rocks in continental magmatic arcs of Oligocene to Pliocene age are assessed for porphyry Cu±Mo±Au deposits. The area of this tract is 32,840 km 2 . The total tonnage of ore reported for the 1 known deposit is 44.8 Mt containing 0.224 Mt copper. An estimated 1.4 undiscovered deposits contain a calculated mean of 1.8 Mt copper and a median of 0.72 Mt copper. The spatial density for the 2.4 known plus estimated undiscovered deposits in this permissive tract is approximately 7 deposits per 100,000 km 2 . Western Canada has been thoroughly explored for porphyry copper deposits. The total estimated copper contained in known deposits is about 66.8 Mt (based on 2010 data), as compared to a 49 Mt mean of estimated copper in undiscovered deposits and a 34 Mt median of estimated copper in undiscovered deposits. The copper contained in known porphyry copper deposits represents about 58 percent of the total of known and undiscovered porphyry copper deposits (based on mean values). About 86 percent of the increase in estimated copper resources between 1993 and 2009 resulted from the discovery of extensions to known deposits. Nevertheless, exploration for undiscovered deposits continues, especially in and around significant prospects and in parts of permissive tracts that are mostly hidden beneath younger volcanic, sedimentary, or vegetated surficial cover.

British Columbia, Yukon Territory↗

Geologic, geochemical and mineral resource potential map of the Piney Creek Wilderness, Stone and Barry counties, Missouri

There is no evidence of significant metallic-mineral deposits in the rock units that are exposed at the surface in the wilderness, but there may be some potential for mineral deposits of two different types at depths from 400ft (120 m) to more than 2,100 ft (640 m) below the surface. Analyses of rock samples from a drill hole 15 mi (24 km) south of the area showed anomalous amounts of several metals in the Derby-Doerun (usage of the Missouri Geological Survey), Potosi, and Eminence Dolomites, which suggests that these units as well as the subsurface Ordovician carbonate units may have a potential for zinc-lead mineralization in the wilderness. Also, a high-amplitude magnetic anomaly along the northwest side of the wilderness suggests a potential for a small to moderate-sized magnetite (iron ore) deposit in the Precambrian basement rocks at a depth of at least 2,100 ft (640 m) below the surface, probably at least partly outside the boundary of the wilderness. In both cases the significance of the potential cannot be evaluated without deep drilling. In the case of the possible magnetite deposit, drilling should be preceded by a detailed magnetic survey to delineate the anomaly more clearly. The wilderness has little potential for resources of industrial minerals because they are readily available elsewhere in the region, and no known potential for energy resources.

Missour↗

Airborne geophysical efforts for critical mineral systems mapping in the southern Midcontinent, USA

The increasing global demand for critical minerals to support energy and technological advancement has accelerated exploration and research efforts for these essential resources. Since 2019, the United States Geological Survey (USGS) Earth Mapping Resources Initiative (EMRI) has worked to modernize geologic mapping of the Nation to better understand its critical mineral resources. To further this initiative, the USGS has flown a series of high-resolution airborne magnetic and radiometric surveys over large areas of the southern Midcontinent. The surveys cover known critical mineral deposits and areas with the potential to host additional critical minerals based on the presence of one or more overlapping mineral systems. One aspect of EMRI emphasizes close collaboration between the USGS and the Association of American State Geologists, as well as other government and industry partners to leverage geophysical, geological, and geochemical expertise on both regional and local scales. The EMRI high-resolution airborne survey data provide new insights into the geophysical framework of the southern Midcontinent and its critical mineral endowment. Additionally, discoveries made from the data have directed new studies for critical mineral exploration.

southern Midcontinent↗

Mineral Resources Data System (MRDS)

The U.S. Geological Survey (USGS) operates the Mineral Resources Data System (MRDS), a digital system that contained 111,955 records on Sept. 1, 1995. Records describe metallic and industrial commodity deposits, mines, prospects, and occurrences in the United States and selected other countries. These records have been created over the years by USGS commodity specialists and through cooperative agreements with geological surveys of U.S. States and other countries. This CD-ROM contains the complete MRDS data base, several subsets of it, and software to allow data retrieval and display. Data retrievals are made by using GSSEARCH, a program that is included on this CD-ROM. Retrievals are made by specifying fields or any combination of the fields that provide information on deposit name, location, commodity, deposit model type, geology, mineral production, reserves, and references. A tutorial is included. Retrieved records may be printed or written to a hard disk file in four different formats: ascii, fixed, comma delimited, and DBASE compatible.

Data Series↗

Geologic map of the Dog River and northern part of the Badger Lake 7.5′ quadrangles, Hood River County, Oregon

The Dog River and northern part of the Badger Lake 7.5' quadrangles encompasses an area of ~201 km2 (77.6 mi2) of the High Cascades of north-central Oregon, lying across the eastern slopes of Mount Hood volcano (Figure 1-1; Plate 1; referred to herein as Dog River–Badger Lake area). Mount Hood, known as Wy’east to Native Americans, is Oregon’s tallest peak (3,427 m [11,241 ft]). The volcano has erupted episodically for the past 500,000 years, experiencing two major eruptive periods during the last 1,500 years (Scott and others, 1997a; Scott and others, 2003; Scott and Gardner, 2017). Cascade Range volcanism and structural development in the area dates back longer, with eruptive activity dating from latest Miocene to recent time; part of that volcano-tectonic record is detailed by new high-resolution geologic mapping presented here. The geology of the Dog River–Badger Lake area was mapped by the Oregon Department of Geology and Mineral Industries (DOGAMI) between 2017 and 2020, in collaboration with geoscientists from the U. S. Geological Survey Cascade Volcano Observatory (USGS CVO) and Hamilton College, New York. The primary objective of this investigation is to provide an updated and spatially accurate geologic framework for the Dog River–Badger Lake area as part of a multi-year study of the geology of the larger Middle Columbia Basin (Figure 1-1, Figure 1-2). Additional key objectives of this project are to: 1) determine the geologic history of volcanic rocks in this part of the northern Oregon Cascade Range, including lava flows and volcaniclastic deposits erupted from Middle Pleistocene to Holocene Mount Hood volcano; 2) provide significant new details about the structure and fault history along the northern segment of the High Cascades intra-arc graben (Hood River graben); and 3) better understand geologic hazards in the region, related to earthquakes, volcanoes, and landslides. New detailed geologic data presented here also provides a basis for future geologic, geohydrologic, and geohazard studies in the greater Middle Columbia Basin. Detailed geologic mapping in this part of the Middle Columbia Basin is a high priority of the Oregon Geologic Map Advisory Committee (OGMAC), supported in part by grants from the STATEMAP component of the USGS National Cooperative Geologic Mapping Program (G17AC00210, G19AC00160). Additional funds were provided by the State of Oregon. The core products of this study are this report, an accompanying geologic map and cross sections (Plate 1), an Esri ArcGIS™ geodatabase, and Microsoft Excel® spreadsheets tabulating point data for geochemistry, geochronology, magnetic polarity, orientation points, and well data. The geodatabase presents the new geologic mapping in a digital format consistent with the USGS National Cooperative Geologic Mapping Program Geologic Map Schema (GeMS) (U.S. Geological Survey National Cooperative Geologic Mapping Program, 2020). This geodatabase contains spatial information, including geologic polygons, contacts, structures, geochemistry, geochronology, magnetic observation, orientation points, and well data, as well as data about each geologic unit such as age, lithology, mineralogy, and structure. Digitization at scales of 1:8,000 or better was accomplished using a combination of high-resolution lidar topography and imagery. Surficial and bedrock geologic units contained in the geodatabase are depicted on the Plate 1 at a scale of 1:24,000. Both the geodatabase and geologic map are supported by this report describing the geology in detail.

Oregon↗

The role of the U.S. Geological Survey in the lithium industry

The U.S. Geological Survey has responsibility in the U.S. Department of the Interior to assess the nation's energy and mineral resources. The evaluation of reserves and resources of a commodity such as lithium should be a continuing process in the light of advancing technology and ever-growing knowledge of its geologic occurrence and geochemical behavior. Although reserves of lithium vary with market demand because of the investment required to find, develop, and appraise an ore body, total resources are a function of the geologic occurrence and geochemical behavior of lithium. By studying known deposits and publishing data on their origin and occurrence, the U.S. Geological Survey can aid in the discovery of new deposits and improve the resource base. Resource data are used both by the government and the private sector. Government funding for research on energy-related technologies such as electric vehicle batteries and fusion power requires assurance that there will be enough lithium available in time for commercialization. Questions of availability for all mineral commodities must be answered by the U.S. Geological Survey so that intelligent decisions can be made.

Energy↗

Tsunami Preparedness Along the U.S. West Coast (video)

Tsunamis are a constant threat to the coasts of our world. Although tsunamis are infrequent along the West coast of the United States, it is possible and necessary to prepare for potential tsunami hazards to minimize loss of life and property. Community awareness programs are important, as they strive to create an informed society by providing education and training. This video about tsunami preparedness along the West coast distinguishes between a local tsunami and a distant event and focuses on the specific needs of each region. It offers guidelines for correct tsunami response and community preparedness from local emergency managers, first-responders, and leading experts on tsunami hazards and warnings, who have been working on ways of making the tsunami affected regions safer for the people and communities on a long-term basis. This video was produced by the US Geological Survey (USGS) in cooperation with the California Emergency Management Agency (CalEMA), Oregon Department of Geology and Mineral Industries (DOGAMI), Washington Emergency Management Division (EMD), Marin Office of Emergency Services, and Pacific Gas and Electric (PG&E).

General Information Product↗

Mineral commodity summaries 2020

Each chapter of the 2020 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2019 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses.

Mineral Commodity Summaries↗

State summaries: Colorado

According to the Colorado Geological Survey (CGS), Colorado's mining industry enjoyed a record-breaking year in 2005. For the whole year, the total value of nonfuel minerals, coal and uranium produced in the state in 2005 amounted to $2.4 billion. The production value of $1.52 billion in the nonfuel sector broke the previous record of $1.3 billion set in 1980, and is 60% higher than the revised 2004 CGS estimate of $950.5 million. The United States Geological Survey (USGS) ranked Colorado ninth among the states in nonfuel mineral value, up from 17th in 2004. About $1 billion of the nonfuel total is from metal mining. New record-high productions were achieved not only for molybdenum but also for coal and goal.

Mining Engineering↗

Minerals, lands, and geology for the common defence and general welfare, Volume 3, 1904-1939 : A history of geology in relation to the development of public-land, federal-science, and mapping policies and the development of mineral resources in the United States from the 25th to the 60th year of the U.S. Geological Survey

Mrs. Rabbitt's third volume covers the years 1904 to 1939, from the beginning of the conservation movement under Theodore Roosevelt to the beginning of World War II. From a national perspective, these were years of great development and change in the use of energy, trouble in the coal industry, and a great expansion in the oil industry. They were also years in which the public perceived for the first time that the Nation's mineral resources are not infinite, and the mineral industry realized its dependence on international trade. In these years, water became an increasingly valuable commodity, and the need for a national mapping program became abundantly evident. These were also the years when the Federal Government for the most part practiced stringent economy in funding science, but State and municipal agencies increasingly sought the services of the Survey's topographic and water specialists to aid in the solution of local problems. The balance maintained between fundamental and practical research during the first 25 years was more than once upset during the next 25 years, but the successful struggle to maintain a significant level of research laid the groundwork for the tremendous expansion in the Survey in the subsequent years.

Book↗