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At least 37 records · Page 2Linked to original sources
USGS2015

Evaluation of selected static methods used to estimate element mobility, acid-generating and acid-neutralizing potentials associated with geologically diverse mining wastes

A comparison study of selected static leaching and acid–base accounting (ABA) methods using a mineralogically diverse set of 12 modern-style, metal mine waste samples was undertaken to understand the relative performance of the various tests. To complement this study, in-depth mineralogical studies were conducted in order to elucidate the relationships between sample mineralogy, weathering features, and leachate and ABA characteristics. In part one of the study, splits of the samples were leached using six commonly used leaching tests including paste pH, the U.S. Geological Survey (USGS) Field Leach Test (FLT) (both 5-min and 18-h agitation), the U.S. Environmental Protection Agency (USEPA) Method 1312 SPLP (both leachate pH 4.2 and leachate pH 5.0), and the USEPA Method 1311 TCLP (leachate pH 4.9). Leachate geochemical trends were compared in order to assess differences, if any, produced by the various leaching procedures. Results showed that the FLT (5-min agitation) was just as effective as the 18-h leaching tests in revealing the leachate geochemical characteristics of the samples. Leaching results also showed that the TCLP leaching test produces inconsistent results when compared to results produced from the other leaching tests. In part two of the study, the ABA was determined on splits of the samples using both well-established traditional static testing methods and a relatively quick, simplified net acid–base accounting (NABA) procedure. Results showed that the traditional methods, while time consuming, provide the most in-depth data on both the acid generating, and acid neutralizing tendencies of the samples. However, the simplified NABA method provided a relatively fast, effective estimation of the net acid–base account of the samples. Overall, this study showed that while most of the well-established methods are useful and effective, the use of a simplified leaching test and the NABA acid–base accounting method provide investigators fast, quantitative tools that can be used to provide rapid, reliable information about the leachability of metals and other constituents of concern, and the acid-generating potential of metal mining waste.

Applied Geochemistry↗
USGS2002

Asbestos: Geology, Mineralogy, Mining, and Uses

The term asbestos is a generic designation referring usually to six types of naturally occurring mineral fibers that are or have been commercially exploited. These fibers belong to two mineral groups: serpentines and amphiboles. The serpentine group contains a single asbestiform variety: chrysotile; five asbestiform varieties of amphiboles are known: anthophyllite asbestos, grunerite asbestos (amosite), riebeckite asbestos (crocidolite), tremolite asbestos, and actinolite asbestos. These fibrous minerals share several properties which qualify them as asbestiform fibers: they are found in bundles of fibers which can be easily separated from the host matrix or cleaved into thinner fibers; the fibers exhibit high tensile strengths, they show high length: diameter (aspect) ratios, from a minimum of 20 up to greater than 1000; they are sufficiently flexible to be spun; and macroscopically, they resemble organic fibers such as cellulose. Since asbestos fibers are all silicates, they exhibit several other common properties, such as incombustibility, thermal stability, resistance to biodegradation, chemical inertia toward most chemicals, and low electrical conductivity. The term asbestos has traditionally been attributed only to those varieties that are commercially exploited. The industrial applications of asbestos fibers have now shifted almost exclusively to chrysotile. Two types of amphiboles, commonly designated as amosite and crocidolite are no longer mined. The other three amphibole varieties, anthophyllite asbestos, actinolite asbestos, and tremolite asbestos, have no significant industrial applications presently.

Open-File Report↗
USGS2023

A review of geology and mining in the Marble Mountains, southeastern California

Mining in the Marble Mountains of southeastern California was active in the earliest 1900s and gradually declined to very few active mines by 1959. Most mining consisted of hard-rock prospects and mines, with a few soft-rock prospects and one mine. The Marble Mountains are a 10 km by 30 km, gently NE-dipping dipping structural block composed of Proterozoic plutonic and metamorphic rocks, Paleozoic sedimentary rocks, and Jurassic granitoids exposed along the western anti-dip slopes, and Miocene volcanic and sedimentary rocks exposed along the crest of the range and eastern dip slopes. Mineralization occurred in metamorphic aureoles of intrusions, along dikes, as contact metasomatic replacement bodies in carbonate rocks, or adjacent to or along thrust faults. Mineralization locally formed gold, copper, malachite, azurite, bornite, chalcopyrite, magnetite, specularite, limonite, quartz, epidote, actinolite, and garnet. Hard-rock prospects and mines are clustered into five locations. The mines are small open pits, a few consist of a shaft or two with a few adits, most are just a single shaft or adit. There are a few small open-pit marble mines, and one is an open pit fossil mine. Eight prospects were developed in the Miocene tuffaceous deposits; three in the northwest and five prospects, and a single adit, in the south. Most of the Marble Mountains are now in the Trilobite Wilderness or adjacent Areas of Critical Environmental Concern, and the area of the Golden Cycle district (Castle Mine area) and prospect areas in the southern part of the range are in the Mojave Trails National Monument. The Iron Hat mine, several nearby areas, and the Trilobite mine area are privately owned. No rock or mineral mines are currently active, but the Trilobite mine in the south end of the range is still open to the public.

California↗
USGS1946

A cotangent ruler for simplifying the graphic solution of problems in structural geology

The cotangent ruler is a device for measuring directly the dip of contoured surfaces, or, conversely, for constructing contours that represent planes of known dip. It greatly simplifies the graphic solution of problems in structural geology, and has several specialized applications to problems commonly encountered in mining geology and areal geologic mapping.

Economic Geology↗
USGS1989

Behaviour of abandoned room and pillar mines in Illinois

Little comprehensive information has been reported on the behaviour of room-and-pillar mines. The objective of this paper is to present case data on mine failures in the Illinois basin for use in practice. Presented are results of an ongoing study and details on the site characteristics of cases where sags have developed on the surface. Site data are reported to show the geologic, mining, and sag conditions that existed. Sags mainly develop from pillar, floor, or pillar-floor failure. The character of the sags depends upon the type of mine failure as well as the overburden response. Preliminary results show that the statistical no-risk tributary pressure decreases over 300% as the mine age increases from about 2 to 100 years at a long-term value of approximately 300 psi (2070 kPa). As more information is collected and more analysis is done, the allowable tributary pressure can be determined for different site conditions. A plot is also reported that depicts the relationship of the maximum subsidence to site conditions. It was found that the modified subsidence factor was heavily dependent upon the overburden rock thickness. ?? 1989 Chapman & Hall Ltd.

International Journal of Mining and Geological Eng↗
USGS1977

Selected Geological Survey, U.S. Bureau of Mines, and Alaska Division of Geological and Geophysical Surveys reports and maps on Alaska released during 1976, indexed by quadrangle

This open-file report lists all Geological Survey, U.S. Bureau of Mines, and State of Alaska Division of Geological and Geophysical Surveys reports and maps on the geology, geophysics, and mineral and water resources of Alaska published or released to open files in 1976. They are listed by the quadrangles (scale 1:250,000) into which Alaska has been subdivided for topographic mapping (p. 3). As these three agencies also issued reports and maps on other subjects, the following lists are selected in the sense that such documents are not included. Most of the listed reports and maps bear a 1976 imprint date; a few with a 1975 imprint date actually were not delivered until 1976. Also included are a few that I overlooked when I prepared a similar index of reports and maps issued in 1975. Reports that deal with regional tectonic hypotheses, regional syntheses, Alaska as a whole, or with areas that can not be identified with a specific quadrangle are listed under Alaska - General, as are statistical presentations, indexes, and the like. Reports and maps 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. This index is intended to bring up to date the other indexes of this series, which are listed on p. 2.

Alaska↗
USGS1978

Selected Geological Survey, U.S. Bureau of Mines, and Alaska Division of Geological and Geophysical Surveys reports and maps on Alaska released during 1977, indexed by quadrangle

This open-file report lists all Geological Survey, U.S. Bureau of Mines, and State of Alaska Division of Geological and Geophysical Surveys reports and maps on the geology, geophysics, and mineral and water resources of Alaska published or released to open files in 1977. They are listed by the quadrangles (scale 1:250,000) into which Alaska has been subdivided for topographic mapping (p. 3). As these three agencies also issued reports and maps on other subjects, the following lists are selected in the sense that such documents are not included. Most of the listed reports and maps bear a 1977 imprint date; a few with earlier imprint dates actually were not delivered until 1977. Reports that deal with regional tectonic hypotheses, regional syntheses, Alaska as a whole, or with areas that can not be identified with a specific quadrangle are listed under Alaska - General, as are statistical presentations, indexes, and the like. Reports and maps 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. This index is intended to bring up to date the other indexes of this series, which are listed on p. 2.

Alaska↗
USGS1979

Selected Geological Survey, U.S. Bureau of Mines, and Alaska Division of Geological and Geophysical surveys reports and maps on Alaska released during 1978, indexed by quadrangle

This open—file report lists all Geological Survey, U.S. Bureau of Mines, and State of Alaska Division of Geological and Geophysical Surveys reports and maps on the geology, geophysics, and mineral and water resources of Alaska published or released to open files in 1978. They are listed by the quadrangles (scale 1:250,000) into which Alaska has been subdivided for topographic mapping (p. 4). As these three agencies also issued reports and maps on other subjects, the following lists are selected in the sense that such documents are not included. Most of the listed reports and maps bear a 1978 imprint date; a few with earlier imprint dates actually were not delivered until 1978. Reports that deal with regional tectonic hypotheses, regional syntheses, Alaska as a whole, or with areas that can not be identified with a specific quadrangle are listed under Alaska — General, as are statistical presentations, indexes, and the like. Reports and maps 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↗
USGS1982

Geologic estimates and future costs of strip mining coal

Geologic coal-resource appraisals, which typically describe the location and general characteristics of coalbeds, do not generally provide enough information to estimate the cost of developing the resource or to predict the escalation of costs expected to result from physical depletion. This paper considers the nature of data and methods of appraisal required to provide this cost information to policymakers. Illinois is used as a prototype area for analysis because of its long history of coal mining and its demonstrated coal reserve base of strippable coal that exceeds all but two of the States in the United States. Evidence of gradual depletion of Illinois strippable coal reserves is provided by declining labor productivity, decreasing average mine size, and increasing overburden depth. The procedures used to estimate the costs of mining remaining deposits indicate that the physical characteristics that will affect mining costs most significantly are depth of overburden, thickness of coal seam, and areal extent of coal of the minable reserve blocks. Findings presented here provide guidelines for the collection of economic and geologic data in order to improve coal appraisals, particularly those currently in progress in the Western United States.

Energy Systems and Policy↗
USGS1980

Geology and mineral resources of the North Absaroka Wilderness and vicinity, Park County, Wyoming, with sections on mineralization of the Sunlight mining region and geology and mineralization of the Cooke City mining district, and a section on aeromagnetic interpretation

SUMMARY The North Absaroka Wilderness is approximately 560 square miles (1,450 km 2 ) of rugged scenic mountainous terrain that adjoins the eastern boundary of Yellowstone National Park in northwestern Wyoming. The area was studied during 1970, 1971, and 1972 by personnel of the U. S. Geological Survey and the U. S. Bureau of Mines to evaluate its mineral-resource potential as required by the Wilderness Act of 1964. This evaluation is based on a search of the literature courthouse and production records, geologic field mapping, field inspection of claims and prospects, analyses of bedrock and stream-sediment samples, and an aeromagnetic survey. The North Absaroka Wilderness is underlain almost entirely by andesitic and basaltic volcanic rocks of Eocene age. These volcanics rest on deformed sedimentary rocks of Paleozoic and, locally, of Mesozoic age that are exposed at places along the northern and eastern edges of the wilderness. Dikes and other igneous intrusive bodies cut both the volcanic and sedimentary rocks. A nearly flat detachment fault, the Heart Mountain fault, and a related steep break-away fault have displaced middle and upper Paleozoic rocks and some of the older part of the volcanic sequence to the southeast. A much greater thickness of volcanic rocks was found to be involved in Heart Mountain faulting than had previously been recognized; however, most of the volcanic rocks and many of the intrusives were emplaced after Heart Mountain faulting. Local folding and high-angle faulting in mid-Eocene time have deformed all but the youngest part of the volcanic sequence in the southeastern part of the wilderness. This deformation is interpreted as the last pulse of Laramide orogeny. The results of this study indicate that the mineral-resource potential of the wilderness is minimal. Bentonite, petroleum, low-quality coal, and localized deposits of uranium and chromite have been produced in the surrounding region from rocks that underlie the volcanic rocks; but such deposits, if present in the wilderness, would be too deeply buried, too small, or too sporadically distributed to be profitably located and exploited. Copper and gold mines and prospects are present on the fringes of the wilderness, but otherwise the area seems to be devoid of economically valuable concentrations of metallic minerals. No surface evidence of geothermal-energy potential was found. Known mineral deposits in the vicinity of the North Absaroka Wilderness are associated with intrusive rocks. From the Cooke City mining district, just north of the wilderness, replacement deposits in Upper Cambrian carbonate rocks may extend a short distance into the north edge of the wilderness, In the Sunlight mining region, an enclave nearly surrounded by the wilderness, mineralization occurs in veins and is disseminated in volcanic and plutonic rocks. Richer concentrations of metallic minerals may occur in carbonate rocks adjacent to intrusive bodies at depth beneath the volcanic rocks in the Sunlight region. A few small intrusive bodies occur in the wilderness, but no significant associated mineralization was detected. Aeromagnetic data indicate that other intrusives not exposed by erosion may occur in the wilderness; however, no significant metamorphism or alteration is evident at the surface to indicate their presence. Although most of the rocks of the wilderness are of igneous origin, they are all so old (Eocene) that it is unlikely that they retain any original heat. The Pleistocene rhyolitic ash-flow tuffs in the southwestern part of the wilderness were erupted from sources in Yellowstone National Park just to the west; however, in the wilderness these tuffs are too thin to contain any residual heat.

Wyoming↗
USGS2005

Geology of the proposed Yucca Mountain repository site, Nevada

Yucca Mountain, located about 100 miles northwest of Las Vegas, Nevada, has been recommended by the President for a mined geologic repository for high-level radioactive waste. This field trip will examine the geologic and hydrologic setting for Yucca Mountain, as well as specific results of the site characterization program. The field trip will visit the locations for underground in situ testing in the “Exploratory Studies Facility” plus several locales for surface-based tests. Discussions will comprise selected topics of Yucca Mountain geology, unsaturated zone hydrology, saturated zone hydrology and geochemistry and will include the probabilistic volcanic hazard analysis and the seismicity and seismic hazard analyses in the Yucca Mountain area. Emphasis of the field trip is the relationship of the geology and hydrology of Yucca Mountain to the performance of a repository that will safely isolate nuclear waste.

Nevada↗
USGS2010

Analogues to features and processes of a high-level radioactive waste repository proposed for Yucca Mountain, Nevada

Natural analogues are defined for this report as naturally occurring or anthropogenic systems in which processes similar to those expected to occur in a nuclear waste repository are thought to have taken place over time periods of decades to millennia and on spatial scales as much as tens of kilometers. Analogues provide an important temporal and spatial dimension that cannot be tested by laboratory or field-scale experiments. Analogues provide one of the multiple lines of evidence intended to increase confidence in the safe geologic disposal of high-level radioactive waste. Although the work in this report was completed specifically for Yucca Mountain, Nevada, as the proposed geologic repository for high-level radioactive waste under the U.S. Nuclear Waste Policy Act, the applicability of the science, analyses, and interpretations is not limited to a specific site. Natural and anthropogenic analogues have provided and can continue to provide value in understanding features and processes of importance across a wide variety of topics in addressing the challenges of geologic isolation of radioactive waste and also as a contribution to scientific investigations unrelated to waste disposal. Isolation of radioactive waste at a mined geologic repository would be through a combination of natural features and engineered barriers. In this report we examine analogues to many of the various components of the Yucca Mountain system, including the preservation of materials in unsaturated environments, flow of water through unsaturated volcanic tuff, seepage into repository drifts, repository drift stability, stability and alteration of waste forms and components of the engineered barrier system, and transport of radionuclides through unsaturated and saturated rock zones.

Professional Paper↗
USGS1980

Minerals, lands, and geology for the common defence and general welfare, Volume 2, 1879-1904 : 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 during the first 25 years of the U.S. Geological Survey

In the traditional view of the Survey's first 25 years, which are the subject of much of this volume, John Wesley Powell, with his broad view of science and advanced ideas of land and water in the West, is the heroic figure. Clarence King is dismissed as brilliant but with a limited view of science as mining geology, and Charles D. Walcott is regarded primarily as a brilliant paleontologist chosen by Powell to succeed him. The Survey's first quarter century, however, spanned a watershed in American history that separated a primarily rural and agrarian nation and a primarily urban and industrial nation, a nation intent on conquering the continent and isolated from the Old World and a nation involved in world politics, a nation that believed in the virtues of competition and limited government and a nation that saw the virtue of cooperation and insisted on reform and regulation to ensure equal opportunities to all. Science itself changed during this period. The age of instruments was just beginning when the Survey was established; by the turn of the century, instruments had almost revolutionized science and the era of the lone investigator had to give way to an era of organized effort in the solution of problems.

Book↗
USGS1990

Coal resources available for development; a methodology and pilot study

Coal accounts for a major portion of our Nation's energy supply in projections for the future. A demonstrated reserve base of more than 475 billion short tons, as the Department of Energy currently estimates, indicates that, on the basis of today's rate of consumption, the United States has enough coal to meet projected energy needs for almost 200 years. However, the traditional procedures used for estimating the demonstrated reserve base do not account for many environmental and technological restrictions placed on coal mining. A new methodology has been developed to determine the quantity of coal that might actually be available for mining under current and foreseeable conditions. This methodology is unique in its approach, because it applies restrictions to the coal resource before it is mined. Previous methodologies incorporated restrictions into the recovery factor (a percentage), which was then globally applied to the reserve (minable coal) tonnage to derive a recoverable coal tonnage. None of the previous methodologies define the restrictions and their area and amount of impact specifically. Because these restrictions and their impacts are defined in this new methodology, it is possible to achieve more accurate and specific assessments of available resources. This methodology has been tested in a cooperative project between the U.S. Geological Survey and the Kentucky Geological Survey on the Matewan 7.5-minute quadrangle in eastern Kentucky. Pertinent geologic, mining, land-use, and technological data were collected, assimilated, and plotted. The National Coal Resources Data System was used as the repository for data, and its geographic information system software was applied to these data to eliminate restricted coal and quantify that which is available for mining. This methodology does not consider recovery factors or the economic factors that would be considered by a company before mining. Results of the pilot study indicate that, of the estimated original 986.5 million short tons of coal resources in Kentucky's Matewan quadrangle, 13 percent has been mined, 2 percent is restricted by land-use considerations, and 23 percent is restricted by technological considerations. This leaves an estimated 62 percent of the original resource, or approximately 612 million short tons available for mining. However, only 44 percent of this available coal (266 million short tons) will meet current Environmental Protection Agency new-source performance standards for sulfur emissions from electric generating plants in the United States. In addition, coal tonnage lost during mining and cleaning would further reduce the amount of coal actually arriving at the market.

Circular↗