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At least 91 records · Page 5Linked to original sources
USGS2020

Systems-deposits-commodities-critical minerals table for the earth mapping resources initiative

To define and prioritize focus areas across the United States with resource potential for 35 critical minerals in a few years’ time, the U.S Geological Survey Earth Mapping Resources Initiative (Earth MRI) required an efficient approach to streamline workflow. A mineral systems approach based on current understanding of how ore deposits that contain critical minerals form and relate to broader geologic frameworks and the tectonic history of the Earth was used to satisfy this Earth MRI need. This report describes the rationale for, and structure of, a table developed for Earth MRI that relates critical minerals and principal commodities to the deposit types and mineral systems in which they are concentrated. The hierarchical relationship between systems, deposits, commodities, and critical minerals makes it possible to define and prioritize each system-based focus area once for all of the critical minerals that it may contain. This approach is advantageous because mineral systems are much larger than individual ore deposits and they generally have geologic features that can be “imaged” by the topographic, geologic, geochemical, and geophysical mapping techniques deployed by Earth MRI.

Open-File Report↗
USGS1985

Stream-sediment and panned-concentrate geochemical maps of the Buffalo Peaks Wilderness Study Area, Lake, Park, and Chaffee counties, Colorado

Under provisions of the Wilderness Act (Public Law 88-577, September 3, 1964), the U.S. Geological Survey and the U.S. Bureau of Mines have been conducting mineral surveys of areas selected for possible inclusion in the National Wilderness Preservation System. This report presents results of geochemical studies carried out in June and July, 1982, as part of the investigation of the Buffalo Peaks Wilderness Study Area, Colo. Stream-sediment and panned-concentrate samples were collected from about 80 sites on streams draining the study area. Analytical results and a sample locality map were published by Domenico and others (1984). The geologic and mineral resource potential maps of the study area were prepared by Hedlund and others (1983). The Buffalo Peaks Wilderness Study Area encompasses a major portion of the Mosquito Range, which is structurally part of the east flank of the north-northwest-trending Sawatch anticline. Bedrock in the west two-thirds of the study area is made up of Precambrian igneous and metamorphic rocks of the core of the anticline, whereas bedrock in the east one-third is mostly east dipping Paleozoic sedimentary rocks. In the vicinity of East and West Buffalo Peaks, the sequence of Paleozoic sedimentary rocks is covered by Tertiary extrusive rocks. Major faults generally run parallel to the north-northwest trend of the Arkansas River Valley, which is an expression of the Arkansas River segment of the Rio Grande depression, and the Sawatch anticline in the study area. Some faults are probably of late Precambrian age; major recurrent displacement is known to have occurred on most faults during Laramide time and in the Pliocene and Miocene. The study area is bounded by several areas of known mineralization (Hedl und and others, 1983). Vein and bedding replacement deposits of silver, zinc, and lead were mined from 1890 until about 1918 in the vicinity of Weston Pass (map A), on the northeastern border of the study area. Gold and silver were mined from about 1860 until about 1880 from veins in the Granite area (map A), on the northwestern border of the study area; minor prospecting activity continues today. From 1935 to 1937, veins of gold, silver, and base metals were mined in the vicinity of Fourmile Creek, on the southwestern border of the study area (map A). Recently, active uranium prospecting has been taking place in the vicinity of the Middle Fork of Salt Creek, on the southeastern border of the study area (map A).

Colorado↗
USGS1971

Preliminary tectonic map of the Arabian Peninsula

In 1963, in response to a request from the Ministry of Petroleum and Mineral Resources, the Saudi Arabian Government and the U. S. Geological Survey, U. S. Department of the Interior, with the approval of the U. S. Department of State, undertook a joint and cooperative effort to map and evaluate the mineral potential of central and western Saudi Arabia. The results of this program are being released in USGS open files in the United States and are also available in the Library of the Ministry of Petroleum and Mineral Resources. Also on open file in that office is a large amount of material, in the form of unpublished manuscripts, maps, field notes, drill logs, annotated aerial photographs, etc., that has resulted from other previous geologic work by Saudi Arabian government agencies. The Government of Saudi Arabia makes this information available to interested persons, and has set up a liberal mining code which is included in "Mineral Resources of Saudi Arabia, a Guide for Investment and Development," published in 1965 as Bulletin 1 of the Ministry of Petroleum and Mineral Resources, Directorate General of Mineral Resources, Jiddah, Saudi Arabia.

Open-File Report↗
USGS1972

Report of the field trip, February 24 to April 2, 1965 in part of the northeastern Hijaz quadrangle, Saudi Arabia

In 1963, in response to a request from the Ministry of Petroleum and Mineral Resources, the Saudi Arabian Government and the U. S. Geological Survey, U. S. Department of the Interior, with the approval of the U. S. Department of State undertook a joint and cooperative effort to map and evaluate the mineral potential of central and Saudi Arabia. The results of this program are being released in USGS open files in the United States and are also available in the Library of the Ministry of Petroleum and Mineral Resources. Also on open file in that office is a large amount of material, in the form of unpublished manuscripts, maps, field notes, drill logs, annotated aerial photographs, etc., that has resulted from other previous geologic work by Saudi Arabian government agencies. The Government of Saudi Arabia makes this information available to interested persons, and has set up a liberal mining coda which is included in "Mineral Resources of Saudi Arabia, a Guide for Investment and Development," published in 1965 as Bulletin 1 of the Ministry of Petroleum and Mineral Resources, Directorate General of Mineral Resources, Jiddah, Saudi Arabia.

Hijaz quadrangle↗
USGS1972

Report on field work in the Mahd adh Dhahab area, Saudi Arabia, February 29 to April 13, 1964

In 1963, in response to a request from the Ministry of Petroleum and Mineral Resources, the Saudi Arabian Government and the U. S. Geological Survey, U. S. Department of the Interior, with the approval of the U. S. Department of State, undertook a joint and cooperative effort to map and evaluate the mineral potential of central and western Saudi Arabia. The results of this program are being released in USGS open files in the United States and are also available in the Library of the Ministry of Petroleum and Mineral Resources. Also on open file in that office is a large amount of material, in the form. of unpublished manuscripts, maps, field notes, drill logs, annotated aerial photographs, etc:, that has resulted from-other previous geologic work by Saudi Arabian government agencies. The Government of Saudi Arabia makes this information available to interested persons, and has set up a liberal mining cods which is included in "Mineral Resources of Saudi Arabia, a Guide for Investment and Development," published in 1965 as Bulletin 1 of the Ministry of Petroleum and Mineral Resources,' Directorate General of Mineral Resources, Jiddah, Saudi Arabia.

Mahd adh Dhahab↗
USGS1967

Iron in the United States, exclusive of Alaska and Hawaii

The iron-ore deposits in the United States (exclusive of Alaska and Hawaii) are shown on the accompanying map; many iron-bearing deposits that are of lesser or only potential value are also shown. Because these deposits range widely in extent, two general categories of symbols are used, each of which is subdivided as explained below. The first category is for deposits of such restricted extent that they can be represented by a "spot": the second is for deposits which, although not necessarily extremely large in terms of volume or tonnage, are either continuous (or essentially so) or clustered in reasonably well-defined districts of numerous small occurrences.

Mineral Investigations Resource Map↗
USGS1979

Alaskan papers and abstracts published in American Association of Petroleum Geologists Bulletin, 1950-1978, indexed by quadrangle

This open—file report lists all papers and abstracts on the geology and mineral resources of Alaska published in the American Association of Petroleum Geologists Bulletin from 1950 through 1978. They are listed by the quadrangles (scale 1:250,000) into which Alaska has been subdivided for topographic mapping (p. 2). Reports that deal with regional tectonic hypotheses, regional syntheses, Alaska as a whole, or with areas that can not be identified with specific quadrangles, and the annual reports of developments in Alaska are listed under Alaska — General. Most abstracts appear in this section because they are so worded that locations can not be determined accurately enough to restrict areas discussed to specific quadrangles. Reports that deal with offshore areas not within quadrangle boundaries are listed under Offshore Areas. The Alaska — General and Offshore Areas lists appear before the alphabetically arranged quadrangle listings.

Alaska↗
USGS1979

Alaskan papers and abstracts published by the Geological Society of America, 1890-1978, indexed by quadrangle

This open—file report lists most papers and abstracts on the geology and mineral resources of Alaska published by the Geological Society of America from 1890 through 1978. They are listed by the quadrangles (scale 1:250,000) into which Alaska has been subdivided for topographic mapping (p. 2). Not included are papers and bibliographies on systematic paleontology. Reports that deal with regional tectonic hypotheses, regional syntheses, Alaska as a whole, or with areas that cannot be identified with specific quadrangles and bibliographies are listed under Alaska — General. Many abstracts appear in this section because they are so worded that locations cannot be determined accurately enough to restrict areas discussed to specific quadrangles. Reports that deal with offshore areas not within quadrangle boundaries are listed under Offshore Areas. The Alaska — General and Offshore Areas lists appear before alphabetically arranged quadrangle listings.

Alaska↗
USGS1999

An interpretation of the aeromagnetic and gravity data and derivative maps of the Craig and Dixon Entrance 1°x 3° quadrangles and the western edges of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska

The U.S. Geological Survey (USGS) is required by the Alaska National Interest Lands Conservation Act (ANILCA, Public Law 96-487) to survey certain Federal lands to determine their mineral resource potential. As part of continuing studies designed to fulfill this responsibility, geochemical, geological and geophysical surveys of the Craig and Dixon Entrance (CDE) 1°x3° quadrangles in southeastern Alaska were undertaken by the USGS during the summers of 1983-85, 1989, and 1991. The geochemical data have been reported by Cathrall and others (1993) and Cathrall (1994). A simplified geologic map has been compiled especially for this report based largely on the work of Eberlein and others (1983) and Gehrels (1991, 1992). Brew (1996) also produced a compilation. This report presents available magnetic and gravity data and an interpretation thereof. In this report (released on CD-ROM in 1999) we are releasing USGS-acquired geophysical data for CDE 1:250,000-scale quadrangles of southeastern Alaska. Much of the data have never appeared before in the public domain, including a simplified geologic map, the raw gravity and magnetic data, and derivative products including depth-to-source images, various grids of the data, imaging representations, rock densities, and overlays of the data. In addition, we have added a limited interpretation of what the gravity and magnetic data indicate about the underlying geology, structures, and their relationship to known and potential hidden mineral resources. This interpretation is necessarily limited in the case of the gravity data by the general sparsity of stations. For convenience, we have also included here various representations of the digital topography.

Alaska↗
USGS1993

Geochemical reconnaissance of the Carroll County Gold Belt and southwestern part of the Dahlonega Gold Belt, western Georgia

The gold deposits in the Carroll County gold belt and the southwestern part of the Dahlonega gold belt are in interlayered metasedimentary and metavolcanic rocks of Late Proterozoic to early Paleozoic age. These rocks are in several thrust sheets that form the southwest continuation of the Blue Ridge thrust stack. The rocks are now mostly mica gneiss and schist, graphitic schist and phyllite, quartzite, amphibolite, and granite gneiss. A sample suite of 788 rock and saprolite samples was collected; the suite represents most of the rock types exposed in the southwest extension of the Dahlonega gold belt in Cherokee, Cobb, Bartow, Paulding, and Haralson Counties, Ga., and in the Carroll County gold belt in Carroll and Douglas Counties, Ga. The samples were analyzed semiquantitatively for 30 elements and quantitatively for gold, copper, lead, and zinc; some samples were also analyzed quantitatively for arsenic, mercury, and molybdenum. Whole-rock analyses were made on 27 samples of relatively fresh mafic rock. More than two-thirds of the samples are saprolite derived from mica schist and gneiss, graphitic schist, amphibolite, and quartzite, or vein quartz in saprolite. The samples were collected from roadcuts, surface and underground mine workings, and mine dumps. Of the samples collected, 78 percent of those from old mine areas and 13 percent of those from roadcuts contain gold at or above a limit of determination of 0.02 parts per million (ppm). Of those samples that contain detectable gold, 36 percent of the mine samples and 92 percent of the roadcut samples have less than 0.2 ppm gold. Gold is present in detectable amounts in some samples from all the major rock types that were sampled. Gold does not correlate consistently with the other elements in the data set. The few positive correlation coefficients greater than 0.50 are restricted to the smaller subsets of a few samples. Most of the old mine areas contain small resources of gold in saprolite and probably larger amounts of lower grade material in unweathered rock. The mineralized zones are generally about 5 to 100ft wide, but may be as much as 250ft wide. Many deposits are only 100 to 800ft long, but a few mineralized zones are longer; one is as much as 0. 75 mi long.

Georgia↗
USGS2015

Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69)

The gold resources of Mauritania presently include two important deposits and a series of poorly studied prospects. The Tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the Rgueïbat Shield and defines a world-class Paleoproterozoic(?) orogenic gold ore system. The producing Guelb Moghrein deposit occurs along a shear zone in Middle Archean rocks at the bend in the Northern Mauritanides and is most commonly stated to be an iron oxide-copper-gold (IOCG) type of deposit, although it also has some important characteristics of orogenic gold and skarn deposits. Both major deposits are surrounded by numerous prospects that show similar mineralization styles. The Guelb Moghrein deposit, and IOCG deposit types in general are discussed in greater detail in a companion report by Fernette (2015). In addition, many small gold prospects, which are probably orogenic gold occurrences and are suggested to be early Paleozoic in age, occur along the length of Southern Mauritanides. Existing data indicate the gold deposits and prospects in Mauritania have a sulfide assemblage most commonly dominated by pyrrhotite and chalcopyrite, and have ore-related fluids with apparently high salinities. A preliminary evaluation of these gold data can be used to develop broad, firstorder tracts defining favorable and permissive areas for gold resources; detailed metamorphic and structural maps are required for more detailed future tract definition. Such a first-order assessment can, nonetheless, broadly identify four tracts of gold resource potential. Three of these are favorable for discovery of new orogenic gold deposits. One tract, although not favorable, is nevertheless permissive for discovery of epithermal gold deposits. Tract 1 is defined by favorable medium metamorphic grade greenstone belts within vast areas of unfavorable high metamorphic grade, Mesoarchean and Paleoproterozoic granite-gneiss basement of the Rgueïbat Shield. Faults >200 km in length following the general strike of the greenstone belts; lineament intersections with both exposed and buried parts of greenstone belts within 500 m of the surface, as defined by aeromagnetic data (Finn and Anderson, 2015); and areas of banded iron formation (BIF) in the belts are particularly favorable areas for hosting gold resources in orogenic gold deposits within and along the margins of the greenstone belts. Tracts 2 and 3, also for orogenic gold, reflect the favorable Proterozoic-Cambrian metamorphic rocks of the Northern and Southern Mauritanides, with >200-km-long faults following the general strike of the range, and areas underlain by ultramafic and BIF rocks being particularly favorable. Outcrops of Triassic-Jurassic igneous rocks along the margins of the Taoudeni Basin define tract 4, which is permissive for epithermal gold deposits. Although extensive data are lacking for the area, carbonate units along the northern side of the Taoudeni Basin could be considered permissive host rocks for Carlin-type mineralization, but the deep-water carbonate lithologies are typically not favorable for such.

Open-File Report↗
USGS2010

Preliminary Aeromagnetic Map of Joshua Tree National Park and Vicinity, Southern California

This aeromagnetic map of Joshua Tree National Park and vicinity is intended to promote further understanding of the geology and structure in the region by serving as a basis for geophysical interpretations and by supporting geological mapping, water-resource investigations, and various topical studies. Local spatial variations in the Earth's magnetic field (evident as anomalies on aeromagnetic maps) reflect the distribution of magnetic minerals, primarily magnetite, in the underlying rocks. In many cases the volume content of magnetic minerals can be related to rock type, and abrupt spatial changes in the amount of magnetic minerals commonly mark lithologic or structural boundaries. Bodies of mafic and ultramafic rocks tend to produce the most intense magnetic anomalies, but such generalizations must be applied with caution because rocks with more felsic compositions, or even some sedimentary units, also can cause measurable magnetic anomalies. The database includes two ASCII files containing new aeromagnetic data and two ASCII files with point locations of the local maximum horizontal gradient derived from the aeromagnetic data. This metadata file describes the horizontal gradient locations derived from new and existing aeromagnetic data. This aeromagnetic map identifies magnetic features as a basis for geophysical interpretations; the gradients help define the edges of magnetic sources. This database updates geophysical information originally presented in smaller-scale formats and includes detailed aeromagnetic data collected by EON Geosciences, Inc.

Open-File Report↗
USGS1977

The Pierre Shale, northern Great Plains; a potential isolation medium for radioactive waste

The purpose of this reconnaissance is to assess the potential of the Pierre Shale, of Late Cretaceous age, as a possible isolation medium for radioactive wastes. The regional stratigraphic and structural setting of the Pierre Shale in the northern Great Plains is summarized from subsurface data. Geologic attributes mapped and employed in the identification of areas warranting further evaluation are: depth to the base of the Pierre Shale, shale thickness, overburden thickness, lithology and mineralogy of the shale, and penetrations by oil and gas wells. Three areas emerge as most favorable; each may contain many potential disposal sites. These large geologic study areas are further described on the basis of general structural and seismic considerations and are compared with respect to topography and mineral and water resources. A large area in west-central South Dakota is recommended for extensive further study. A smaller area in northeastern Colorado also may warrant additional investigation. A relatively small area in north-central North Dakota is also delineated, but currently is not proposed for further studies.

Colorado, Kansas, Montana, Nebraska, North Dakota,↗
USGS2009

Mapping the mineral resource base for mineral carbon-dioxide sequestration in the conterminous United States

This database provides information on the occurrence of ultramafic rocks in the conterminous United States that are suitable for sequestering captured carbon dioxide in mineral form, also known as mineral carbon-dioxide sequestration. Mineral carbon-dioxide sequestration is a proposed greenhouse gas mitigation technology whereby carbon dioxide (CO 2 ) is disposed of by reacting it with calcium or magnesium silicate minerals to form a solid magnesium or calcium carbonate product. The technology offers a large capacity to permanently store CO 2 in an environmentally benign form via a process that takes little effort to verify or monitor after disposal. These characteristics are unique among its peers in greenhouse gas disposal technologies. The 2005 Intergovernmental Panel on Climate Change report on Carbon Dioxide Capture and Storage suggested that a major gap in mineral CO 2 sequestration is locating the magnesium-silicate bedrock available to sequester the carbon dioxide. It is generally known that silicate minerals with high concentrations of magnesium are suitable for mineral carbonation. However, no assessment has been made in the United States that details their geographical distribution and extent, nor has anyone evaluated their potential for use in mineral carbonation. Researchers at Columbia University and the U.S. Geological Survey have developed a digital geologic database of ultramafic rocks in the conterminous United States. Data were compiled from varied-scale geologic maps of magnesium-silicate ultramafic rocks. The focus of our national-scale map is entirely on ultramafic rock types, which typically consist primarily of olivine- and serpentine-rich rocks. These rock types are potentially suitable as source material for mineral CO 2 sequestration.

Conterminous United States↗
USGS2006

Regional surficial geochemistry of the northern Great Basin

The regional distribution of arsenic and 20 other elements in stream-sediment samples in northern Nevada and southeastern Oregon was studied in order to gain new insights about the geologic framework and patterns of hydrothermal mineralization in the area. Data were used from 10,261 samples that were originally collected during the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program in the 1970s. The data are available as U.S. Geological Survey Open-File Report 02-0227. The data were analyzed using traditional dot maps and interpolation between data points to construct high-resolution raster images, which were correlated with geographic and geologic information using a geographic information system (GIS). Wavelength filters were also used to deconvolute the geochemical images into various textural components, in order to study features with dimensions of a few kilometers to dimensions of hundreds of kilometers. The distribution of arsenic, antimony, gold, and silver is different from distributions of the other elements in that they show a distinctive high background in the southeast part of the area, generally in areas underlain by the pre-Mesozoic craton. Arsenic is an extremely mobile element and can be used to delineate structures that served as conduits for the circulation of metal-bearing fluids. It was used to delineate large crustal structures and is particularly good for delineation of the Battle Mountain-Eureka mineral trend and the Steens lineament, which corresponds to a post-Miocene fault zone. Arsenic distribution patterns also delineated the Black Rock structural boundary, northwest of which the basement apparently consists entirely of Miocene and younger crust. Arsenic is also useful to locate district-sized hydrothermal systems an d clusters of systems. Most important types of hydrothermal mineral deposit in the northern Great Basin appear to be strongly associated with arsenic; this is less so for low-sulfidation epithermal deposits. In addition to individual elements, the distribution of factor scores that resulted from principal component studies of the data was used. The strongest factor is characterized by Fe, Ti, V, Cu, Ni, and Zn and is used to map the distribution of distinctive basalts that are high in Cu, Ni, and Zn and that appear to be related to the Steens Basalt. The other important factor is related to hydrothermal precious metal mineralization and is characterized by Sb, Ag, As, Pb, Au, and Zn. The map of the distribution of this factor is similar in appearance to the one for arsenic, and we used wavelength filters to remove regional variations in the background for this factor score. The resulting residual map shows a very strong association with the most significant precious metal deposits and districts in the region. This residual map also shows a number of areas that are not associated with known mineral deposits, illustrating the utility of the method as a regional exploration tool. A number of these prospective areas are distant from known significant mineral deposits. The deconvolution of the spatial wavelength structure of geochemical maps, combined with the use of large regional geochemical data sets and GIS, permits new possibilities for the use of stream-sediment geochemistry in the study of large-scale crustal features as well as the isolation of mineral-district scale anomalies. ?? 2006 Society of Economic Geologists, Inc.

Economic Geology↗
USGS2018

Aeromagnetic map of Mountain Pass and vicinity, California and Nevada

Magnetic 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 the state boundary between southeastern California and southern Nevada, encompasses Mountain Pass, which is host to one of the world’s largest rare earth element carbonatite deposits. The deposit is found along a north-northwest-trending, fault-bounded block that extends along the eastern parts of the Clark Mountain Range, Mescal Range, and Ivanpah Mountains. This Paleoproterozoic block is composed of a 1.7-Ga metamorphic complex of gneiss and schist that underwent widespread metamorphism and associated plutonism during the Ivanpah orogeny. The Paleoproterozoic rocks were intruded by a Mesoproterozoic (1.4 Ga) ultrapotassic alkaline intrusive suite and carbonatite body. The intrusive rocks include, from oldest to youngest, shonkinite, mesosyenite, syenite, quartz syenite, potassic granite, carbonatite, carbonatite dikes, and late shonkinite dikes. Generally speaking, magnetic anomalies reflect lateral changes in subsurface magnetization that can be used to infer subsurface geologic structure, revealing variations in lithology and delineating geologic features such as faults, plutons, volcanic rocks, calderas, and sedimentary basins. A regional aeromagnetic map was derived from statewide aeromagnetic maps of California and Nevada that were compiled from numerous surveys flown at various flightline altitudes and spacings. This compilation, although composed of surveys acquired using different specifications, allows seamless interpretation of magnetic anomalies across survey boundaries. In addition, a high-resolution aeromagnetic survey was flown by helicopter over parts of the Clark Mountain Range, Mescal Range, and Ivanpah Mountains. The resulting mapped magnetic anomalies show in much greater detail the complex subsurface structures in the Mountain Pass area.

California, Nevada↗
USGS2009

Aeromagnetic survey map of the central California Coast Ranges

This aeromagnetic survey was flown as part of a Cooperative Research and Development Agreement (CRADA) with the Pacific Gas and Electric Company and is intended to promote further understanding of the geology and structure in the central California Coast Ranges by serving as a basis for geophysical interpretations and by supporting geological mapping, mineral and water resource investigations, and other topical studies. Local spatial variations in the Earth's magnetic field (evident as anomalies on aeromagnetic maps) reflect the distribution of magnetic minerals, primarily magnetite, in the underlying rocks. In many cases the volume content of magnetic minerals can be related to rock type, and abrupt spatial changes in the amount of magnetic minerals can commonly mark lithologic or structural boundaries. Bodies of serpentinite and other mafic and ultramafic rocks tend to produce the most intense magnetic anomalies, but such generalizations must be applied with caution because rocks with more felsic compositions, such as the porphyritic granodiorite-granite of the La Panza Range, and even some sedimentary units, also can cause measurable magnetic anomalies.

California↗
USGS1965

Preliminary map of the conterminous United States showing depth to and quality of shallowest ground water containing more than 1,000 parts per million dissolved solids

In this atlas, mineralized ground water is viewed presently as a source of water in some areas, but in much of the country as a source for future development. Mineralized water underlies large areas of the country, and its importance will grow as present supplies of fresh water are appropriated and developed. The potential uses fall in two main categories: (1) direct use in industrial processes, such as cooling, or for irrigation, where a moderate mineral content may not be a disadvantage; and (2) use after demineralization or dilution to whatever degree may be required by the intended user. It is clearly more efficient to produce and process water of moderate mineralization at points of use, where available in adequate amounts, than it is to process ocean water and pump it many miles from the sea. The Geological Survey, as a part of its responsibility to describe the water resources of the United States, has surveyed the known occurrences of mineralized ground water in the conterminous United States. The results are shown on the maps (sheets 1 and 2). This atlas was prepared to meet needs for information on the distribution and availability of mineralized water as expressed by Government agencies, private industries, and consultants. The maps are one step in providing an inventory of mineralized water of the Nation and will serve as a planning guide for further investigations and for development. They are necessarily generalized in many places owing to the complexity of the occurrence of the mineralized water, lack of detailed information for parts of the nation, and the difficulties inherent in attempts to put three-dimensional information on maps.

Hydrologic Atlas↗