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At least 793 records · Page 44Linked to original sources
USGS1979

A proposed U.S. resource classification system

Energy is a worldwide problem calling for worldwide communication to resolve the many supply and distribution problems. Essential to a communication problem is a definition and comparability of elements being communicated. The U.S. Geological Survey, with the cooperation of the U.S. Bureau of Mines and the U.S. Department of Energy, has devised a classification system for all mineral resources, the principles of which we believe offer the possibility of world communication. At this time several other systems, extant or under development (Potential Gas Committee of the U.S., United Nations Resource Committee, and the American Society of Testing and Materials), are internally consistent and provide easy communication linkage. The system in use by the uranium community in the United States, however, ties resource quantities to Forward-Cost dollar values rendering them inconsistent with other classifications and not therefore comparable. The paper will then develop the rationale for the new USGS resource classification and note its benefits relative to a Forward-Cost classification and its relationship specifically to other extant classifications.

Open-File Report↗
USGS1991

Element dispersion in alluvium covering gold deposits east of the Osgood Mountains, Getchell Trend, Humboldt County, Nevada: slides and text of a talk given at the Association of Exploration Geochemists' 15th International Geochemical Exploration Symposium, Reno, Nevada

The current trend in mineral exploration is to search for covered deposits. In the Great Basin, this translates into searching for ore bodies buried by alluvial cover. The exploration techniques used range from random drilling to the use of new and exciting geochemical sampling media and analytical methods. But we have a problem. Many of our geochemical techniques lack a conceptual basis (We tried it and it worked) or the original conceptual basis is now suspect (The method also works when it shouldn't). What we need is a basic understanding of what is going on in the alluvium -- the third dimension. The discovery and development of the alluvium-covered, disseminated gold deposits at Rabbit Creek, Chimney Creek, and Pinson provides us with an opportunity to gain some knowledge of the dispersion of elements in the third dimension. The work presented here is one part of a larger multi-disciplinary study of the Kelly Creek Valley by the U.S. Geological Survey in cooperation with FirstMiss Gold, Inc., Gold Fields Mining Corporation, Pinson Mining Company, and Santa Fe Pacific Mining, Inc.

Nevada↗
USGS2011

Statistical methods of estimating mining costs

Until it was defunded in 1995, the U.S. Bureau of Mines maintained a Cost Estimating System (CES) for prefeasibility-type economic evaluations of mineral deposits and estimating costs at producing and non-producing mines. This system had a significant role in mineral resource assessments to estimate costs of developing and operating known mineral deposits and predicted undiscovered deposits. For legal reasons, the U.S. Geological Survey cannot update and maintain CES. Instead, statistical tools are under development to estimate mining costs from basic properties of mineral deposits such as tonnage, grade, mineralogy, depth, strip ratio, distance from infrastructure, rock strength, and work index. The first step was to reestimate "Taylor's Rule" which relates operating rate to available ore tonnage. The second step was to estimate statistical models of capital and operating costs for open pit porphyry copper mines with flotation concentrators. For a sample of 27 proposed porphyry copper projects, capital costs can be estimated from three variables: mineral processing rate, strip ratio, and distance from nearest railroad before mine construction began. Of all the variables tested, operating costs were found to be significantly correlated only with strip ratio.

Conference Paper↗
USGS1999

Progress of environmental studies in coal mining areas of western Pennsylvania and central West Virginia

Two studies related to the regional environmental effects of coal mining in the Appalachian Plateau were conducted in 1998 as part of the National Water‐Quality Assessment program of the U.S. Geological Survey. The study area of about 20,000 square miles included parts of the Allegheny and Monongahela River basins in the north and the Kanawha River basin in the south. Water in domestic wells downgradient from fully reclaimed surface coal mines was compared to water in similar wells at unmined sites. As expected, pH was lower and the concentration of sulfate was greater at mined sites in both areas, although the pH difference was greater in the southern area. Median concentrations of iron and manganese exceeded federal drinking‐water standards at mined sites in both areas and at unmined sites in the southern area. Median concentrations of radon near reclaimed mines were about half those at unmined sites. Surface water was sampled during summer base flow at about 180 sites that drain between 5 and 80 square miles; the sites also were sampled during 1979‐81. Median pH in 1998 was 7.9 in the north and 7.4 in the south, about 0.5 unit higher than in 1980 in both areas. Median concentrations of sulfate increased from 38 mg/L to 56 mg/L in the north and from 46 mg/L to 77 mg/L in the south, in apparent contradiction to the generally lower sulfur content of geologic units in the southern area. Among 52 basins where mining occurred both before and after 1980, the sulfate concentration more than doubled in 13 (25 percent), including greater than five‐fold increases in 5 (10 percent). For 16 mined basins where no mining has occurred since 1980, the median decrease in sulfate concentration was 18 percent, from which the half‐time for oxidation of mining‐related pyrite is estimated to be about 65 years.

Pennsylvania, West Virginia↗
USGS2019

Assessment of coal mine methane (CMM) and abandoned mine methane (AMM) resource potential of longwall mine panels: example from Northern Appalachian Basin, USA

"Coal mine methane (CMM) and abandoned mine methane (AMM), are by-products of underground coal mining. The quantity and the emission rate of CMM and AMM may vary depending on the type of mine, gas content of the mined coal seam, and gas sourced from strata and coal beds in overlying and underlying formations affected by mining. Therefore, if a mine has the potential of accumulating gas after being abandoned and sealed properly, methane may be produced and used as an energy source to serve to local communities around the mine. Producing AMM also prevents methane, which is a potent greenhouse gas, from leaking to the atmosphere through seals, shaft plugs or surface cracks. One of the technical barriers in front of investments to economical utilization of CMM and AMM is the difficulty to predict how much methane may be available in the gas emission zone (GEZ) as a resource during mining, and after the panels are sealed and the mine is abandoned. Another difficulty is to estimate how much of the potential methane resource can be produced, and its production feasibility with boreholes, such as gob gas ventholes (GGV) converted to capture AMM. In this study, a comparative assessment is presented to address the issues stated above. The assessment was conducted on two adjacent panels of a longwall mine that operated until 2016 in the Pennsylvania section of the Northern Appalachian Basin. The study is based on two approaches that might be used depending on the availability of data, extensive or minimal. The first approach uses an extensive geological data set, geostatistics, and measured shaft gas emission and GGV production values that were collected while the panel(s) were active to assess the AMM resource. The second approach uses a minimal amount of geologic data and its uncertainty as probabilistic distributions as well as predicted during-mining emissions using a publicly available software. Results showed that both approaches provide relatively comparable estimates of AMM resources and AMM recovery potential using wellbores. The differences in assessed quantities are mostly due to the characteristics of the two methods. In that regard, this paper can be considered as guidance to choose the assessment approach based on data availability. "

Northern Appalachian Basin↗
USGS2025

The abandoned mine inventory of the United States—A brief summary

The Infrastructure Investment and Jobs Act of 2021 required the Secretary of the Interior to establish a program to inventory abandoned hard-rock mines in the United States. The Department of the Interior’s Office of Environmental Policy and Compliance asked the U.S. Geological Survey’s Mineral Deposit Database project (USMIN) to use existing data sources to build an inventory of all individual abandoned mine features in the United States. In addition to feature locations, this new database documents the surface land management agency, associated physical and environmental hazards, and any completed mitigation efforts. This information will improve risk assessment and support land management efforts, including hazard mitigation, ecosystem restoration planning, and reclamation. This fact sheet provides a brief overview of USMIN’s collaborative efforts with Federal, State, and Tribal agencies to build a comprehensive and authoritative national inventory of abandoned mine features.

Fact Sheet↗
USGS2011

Review of samples of tailings, soils, and stream sediments adjacent to and downstream from the Ruth Mine, Inyo County, California

The Ruth Mine and mill are located in the western Mojave Desert in Inyo County, California (fig. 1). The mill processed gold-silver (Au-Ag) ores mined from the Ruth Au-Ag deposit, which is adjacent to the mill site. The Ruth Au-Ag deposit is hosted in Mesozoic intrusive rocks and is similar to other Au-Ag deposits in the western Mojave Desert that are associated with Miocene volcanic centers that formed on a basement of Mesozoic granitic rocks (Bateman, 1907; Gardner, 1954; Rytuba, 1996). The volcanic rocks consist of silicic domes and associated flows, pyroclastic rocks, and subvolcanic intrusions (fig. 2) that were emplaced into Mesozoic silicic intrusive rocks (Troxel and Morton, 1962). The Ruth Mine is on Federal land managed by the U.S. Bureau of Land Management (BLM). Tailings from the mine have been eroded and transported downstream into Homewood Canyon and then into Searles Valley (figs. 3, 4, 5, and 6). The BLM provided recreational facilities at the mine site for day-use hikers and restored and maintained the original mine buildings in collaboration with local citizen groups for use by visitors (fig. 7). The BLM requested that the U.S. Geological Survey (USGS), in collaboration with Chapman University, measure arsenic (As) and other geochemical constituents in soils and tailings at the mine site and in stream sediments downstream from the mine in Homewood Canyon and in Searles Valley (fig. 3). The request was made because initial sampling of the site by BLM staff indicated high concentrations of As in tailings and soils adjacent to the Ruth Mine. This report summarizes data obtained from field sampling of mine tailings and soils adjacent to the Ruth Mine and stream sediments downstream from the mine on June 7, 2009. Our results permit a preliminary assessment of the sources of As and associated chemical constituents that could potentially impact humans and biota.

California↗
USGS2007

Geochemistry of Surface and Ground Water in Cement Creek from Gladstone to Georgia Gulch and in Prospect Gulch, San Juan County, Colorado

In San Juan County, Colo., the effects of historical mining continue to contribute metals to ground water and surface water. Previous research by the U.S. Geological Survey identified ground-water discharge as a significant pathway for the loading of metals to surface water in the upper Animas River watershed from both acid-mine drainage and acid-rock drainage. In support of this ground-water research effort, Prospect Gulch was selected for further study and the geochemistry of surface and ground water in the area was analyzed as part of four sampling plans: (1) ten streamflow and geochemistry measurements at five stream locations (four locations along Cement Creek plus the mouth of Prospect Gulch from July 2004 through August 2005), (2) detailed stream tracer dilution studies in Prospect Gulch and in Cement Creek from Gladstone to Georgia Gulch in early October 2004, (3) geochemistry of ground water through sampling of monitoring wells, piezometers, mine shafts, and springs, and (4) samples for noble gases and tritium/helium for recharge temperatures (recharge elevation) and ground-water age dating. This report summarizes all of the surface and ground-water data that was collected and includes: (1) all sample collection locations, (2) streamflow and geochemistry, (3) ground-water geochemistry, and (4) noble gas and tritium/helium data.

Colorado↗
USGS1990

Hydrologic data collected in the vicinity of the proposed gamma-ray and neutrino detector site, Hot Spring County, Arkansas, 1988-89

An abandoned barite mine in Hot Spring County, Arkansas, has been selected as the location for a proposed gamma-ray and neutrino detector site. As part of the hydrologic evaluation of the site, the U.S. Geological Survey in cooperation with the Arkansas Geological Commission collected hydrologic data at selected locations in the vicinity of the abandoned barite mine. Data collected as part of the project included water quality, pond-evaluation, and precipitation data within the abandoned barite mine and flow and water quality data at selected sites in the vicinity of the mine. Water quality samples from within the abandoned mine were collected at three locations in the pond at selected depths. These data included field measurements of specific conductance, pH, water temperature, dissolved oxygen, major ions, and trace metals. Major ion and trace-metal samples were collected at six stream sites, one lake site, and two wastewater pond sites. Pond elevation and precipitation data from within the abandoned barite mine were measured during the period between July 1, 1988 and June 30, 1989. Twevle discharge measurements during the period between June 21, 1988, and June 26, 1989, were collected at six sites in the vicinity of the abandoned barite mine. (USGS)

Open-File Report↗
USGS1953

Occurrences of uranium-bearing minerals in the St. Kevin District, Lake County, Colorado

Two hundred and seventy-one prospect pits, mine dumps, or mine workings within the Sugar Loaf-St. Kevin mining districts and vicinity were tested for radioactivity by the U.S. Geological Survey in 1951 during six weeks of investigation on behalf of the Division of Raw Materials of the U.S. Atomic Energy Commission. One hundred and twenty-two weak radioactivity anomalies were found in the St. Kevin district and vicinity, and eight slight anomalies were noted in the Sugar Loaf district, which adjoins the St. Kevin district on the south. Most of the radioactivity anomalies were found in igneous and metamorphic rocks of pre-Cambrian age, but some were found in metalliferous veins of Tertiary age. Samples of altered granite or schist contain as much as 0.065 percent uranium, probably in the form of secondary uranium minerals. Samples of vein material contain as much as 0.013 percent uranium, also probably in the form of secondary uranium minerals. At only a few localities has the identity of the uranium-bearing minerals been determined. Torbernite, associated with turquoise, malachite, and chrysocolla, occurs as disseminations and fracture coatings in altered granite at the Josie May turquoise mine; metatobernite is disseminated in granite at the Turquoise Chief mine. Commonly the limonite-stained fractures in the altered granite and schist are radioactive; metatorbernite has been identified in limonite stain at one locality. A uranium-variety of florencite, a hydrous cerium aluminum phosphate, is disseminated in the granite on the dump of a mine just west of the St. Kevin district, and autunite (?) is disseminated in fine-grained, highly silicified rock in the northeastern part of the St. Kevin district. None of the uranium occurrences are of commercial importance. They are for the most part in non-glaciated terrane, which has been subjected to a very long period of weathering. Thus, chemical leaching within the zone of weathering may have greatly reduced the uranium content of material near the surface, and occurrences of even small quantities of secondary uranium minerals might be related to stronger, primary concentrations at depth.

Colorado↗
USGS2007

An innovative carbonate coprecipitation process for the removal of zinc and manganese from mining impacted waters

Although mine drainage is usually thought of as acidic, there are many cases where the water is of neutral pH, but still contains metal species that can be harmful to human or aquatic animal health, such as manganese (Mn) and zinc (Zn). Typical treatment of mine drainage waters involves pH adjustment, but this often results in excessive sludge formation and removal of nontoxic species such as magnesium and calcium. Theoretical consideration of the stability of metal carbonate species suggests that the target metals could be removed from solution by coprecipitation with calcium carbonate. The U.S. Geological Survey has developed a limestone-based process for remediation of acid mine drainage that increases calcium carbonate saturation. This treatment could then be coupled with carbonate coprecipitation as an innovative method for removal of toxic metals from circumneutral mine drainage waters. The new process was termed the carbonate coprecipitation (CCP) process. The CCP process was tested at the laboratory scale using a synthetic mine water containing 50 mg/L each of Mn and Zn. Best results showed over 95% removal of both Mn and Zn in less than 2 h of contact in a limestone channel. The process was then tested on a sample of water from the Palmerton zinc superfund site, near Palmerton, Pennsylvania, containing over 300 mg/L Zn and 60 mg/L Mn. Treatment of this water resulted in removal of over 95% of the Zn and 40% of the Mn in the limestone channel configuration. Because of the potential economic advantages of the CCP process, further research is recommended for refinement of the process for the Palmerton water and for application to other mining impacted waters as well. ?? Mary Ann Liebert, Inc.

Environmental Engineering Science↗
USGS1953

Reconnaissance geology of placer deposits containing radioactive minerals in the Bear Valley district, Valley County, Idaho

A reconnaissance of the Bear Valley district was undertaken to provide a geologic interpretation of placer deposits drilled by the U.S. Bureau of Mines. The placer minerals are monazite and a group of uranium bearing rare earth columbates and tantalates here referred to loosely as radioactive blacks. The monazite is an accessory mineral in the granitic country rock; the radioactive blacks occur in pegmatite dikes. The supply of these minerals to the placers was controlled (1) by the geography of their occurrence in the parent rock, and (2) by the distribution of alpine glaciers during two late Pleistocene glacial stages. By reason of a favorable combination of these factors, the richest placer deposits of the district are in Big Meadow, a valley fill formed as a result of the blocking of Bear Creek by a glacier from a tributary valley during the Illinoian (?) stage. The Big Meadow fill consists of intertonguing depositional units formed by Bear Creek and its tributaries, including both normal alluvium and glacial outwash, and ranging from rich to barren. The richest phase that has been blocked out by drilling was derived from the drainage basin of Casner Creek, an east tributary of Bear Creek. The geologic relations suggest that a neighboring stream, Howard Creek, should have supplied equally rich material, but the part of the valley fill formed by Howard Creek has not been tested. The Howard Creek deposits and shallow alluvium in the upper valleys of Casner and Howard Creeks may considerably increase the reserves of the district.

Open-File Report↗
USGS1927

Potash brines in the Great Salt Lake Desert, Utah

During and immediately after the war the brines of the Salduro Marsh, in the Great Salt Lake Desert, were a source of considerable potash for the domestic supply. Although no potash has been produced from these brines in the last few years, a continued interest in the area has been shown by a large number of filings, in different parts of the desert, under the potash law of October 2, 1917 (40 Stat. 297), and the regulations issued under that law by the Department of the Interior on March 21, 1918, in Circular 594 (46 L. D. 323). As the basis for appropriate action on these permit, lease, and patent filings the Department of the Interior required information concerning the mode of occurrence, distribution, and general characteristics of the potassium-bearing brines in this region. Field investigation was accordingly undertaken for the primary purpose of satisfying these requirements. The work was done by the Geological Survey and the General Land Office in cooperation with the Bureau of Mines. The Bureau of Mines furnished an autotruck and a mechanic, who also assisted in the field work, and, for a period of a month, a mine rescue car, which permitted the establishment of headquarters in parts of the desert far from sources of supplies and water. The General Land Office surveyed the boundaries of townships over the desert and located the drill holes from which samples of brine were taken. The writer directed the work for the Geological Survey, and the analyses of the samples of brine were made in the Survey's chemical laboratory. The greater part of the field work was done between April 17 and July 7, 1925, and the work was finished during the two periods August 17-26 and September 30 to October 2 . Adverse weather throughout the season hindered the work.

Utah↗
USGS1946

Sedimentary and volcanic processes in the formation of high alumina clay

In the West, where volcanic materials are abundantly distributed among the rocks of the geologic column, the importance of sedimentary processes in the formation of high-alumina clays has not been fully appreciated. At Ione, Calif., Castle Rock, Wash., Whiteware, Mont., Hobart Butte and Mollala, Oreg., where the Geological Survey has been investigating clays jointly with the Bureau of Mines, U. S. Department of the Interior, high-alumina clays formed by sedimentary processes are more important than those formed by all phases of volcanic activity. Clays derived directly from volcanic materials are composed dominantly of montmorillonite; but these clays, with the exception of the beidellite-nontronite varieties, have relatively low percentages of available alumina. In contrast, clays derived by thorough leaching of various aluminous rocks under conditions favoring thorough drainage are composed dominantly of kaolinite and when sorted by sedimentary processes form high-grade deposits; furthermore, the depositional structures of these sedimentary clays have favored the derivation of gibbsite through weathering, resulting in an increase in the alumina content of the clays. Kaolinite, gibbsite, and dickite all have relatively high percentages of available alumina.

Economic Geology↗
USGS1994

Geologic map of the Venezuela part of the Puerto Ayacucho 2 degrees x 3 degrees Quadrangle, Amazonas Federal Territory, Venezuela

This map is one of a series of 1:500,000-scale maps that, along with several other products, stems from a cooperative agreement between the U.S. Geological Survey (USGS) and the Corporacion Venezolana de Guayana, Tecnica Minera, C.A. (TECMIN), a Venezuelan Government-owned mining and mineral exploration company. The agreement covered cooperative work carried out in the Precambrian Shield of southern Venezuela during 1987-1991 and included a geologic and mineral resource inventory, technology transfer, and scientific training (Wynn and others, in press). The Precambrian Guayana Shield (Escudo de Guyana, not to be confused with the neighboring country of Guyana) includes some of the oldest known rocks in the world (Mendoza, 1977) and also covers parts of neighboring Guyana, Surinam, French Guiana, Columbia, and Brazil. In Venezuela, it underlies most of Bolivar state and all of the Amazonas Federal Territory (see index map).

Puerto Ayacucho↗
USGS1959

The Elk Ridge-White Canyon channel system, San Juan County, Utah: Its effect on uranium distribution

Reconnaissance in the White Canyon district, San Juan County, Utah, indicates that rocks of the Shinarump member of the Chinle formation of Triassic age were deposited in that district in two different channel systems; sediments deposited in channels of one system were derived from a source to the east and sediments of the other from a source to the south. The channel system containing sediments derived from the east, the Elk Ridge-White C anyon channel system, was apparently formed by a large braided stream that flowed westward from a source in granitic and metamorphic terrane of the ancestral Uncompahgre highland. All known uranium deposits of any consequence in the White Canyon district are confined to the Shinarump member deposited in the Elk Ridge-White Canyon channel system. The nature of the channels and the lithologic characteristics of the rocks filling this system of channels combine to form a much more favorable environment for the localization of uranium deposits than do the channels formed and the rocks deposited by northward-flowing streams. Recognition of channel systems in the White Canyon district suggests that channel systems may be recognized elsewhere in the Shinarump member, and that the Shinarump member on the Colorado Plateau may be composed of rocks deposited in many coalescing channel systems. In addition, study in the White Canyon district indicates that rocks deposited in some of these channel systems are more favorable hosts for uranium deposits than the rocks deposited in others. Recognition and delineation of these ancient channel systems may be-of help in making regional appraisals of ore potential and in the search for new mining districts.

Utah↗