Geology ReportsSearch

SEARCH · Geology Reports

Results for “Mining Geology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

Geology & mineralogy of the Old Mine Park area Trumbull Connecticut

Old Mine Park, in the northern Trumbull area (also known as Long Hill) of southwestern Connecticut, is a recreation area encompassing the mineral-rich hill of “Saganawamps” and owned by the Town of Trumbull. Most of its 72 acres are wooded, rocky and undeveloped but it is surrounded by dense infrastructure and transportation, residential, retail, and commercial development (Figure 1). It preserves the first tungsten mine operated east of the Mississippi and the first topaz locality identified in the USA (Hitchcock and Silliman, 1825), as well as the type locality for the mineral tungstite (WO 3 ·H 2 O). Hiking and biking trails cross the property and continue beyond the park along the former New Haven railroad line that parallels the Pequonnock River, which flows through the southern part of the park. Access is from the south via Old Mine Road, or from the north via Corporate Drive. During the mining era and for many decades after its creation the park was a famous source of mineral specimens. In 2016 the Trumbull Parks and Recreation Commission suspended collecting of any kind.

Connecticut

CoalVal-A coal resource valuation program

CoalVal is a menu-driven Windows program that produces cost-of-mining analyses of mine-modeled coal resources. Geological modeling of the coal beds and some degree of mine planning, from basic prefeasibility to advanced, must already have been performed before this program can be used. United States Geological Survey mine planning is done from a very basic, prefeasibility standpoint, but the accuracy of CoalVal's output is a reflection of the accuracy of the data entered, both for mine costs and mine planning. The mining cost analysis is done by using mine cost models designed for the commonly employed, surface and underground mining methods utilized in the United States. CoalVal requires a Microsoft Windows? 98 or Windows? XP operating system and a minimum of 1 gigabyte of random access memory to perform operations. It will not operate on Microsoft Vista?, Windows? 7, or Macintosh? operating systems. The program will summarize the evaluation of an unlimited number of coal seams, haulage zones, tax entities, or other area delineations for a given coal property, coalfield, or basin. When the reader opens the CoalVal publication from the USGS website, options are provided to download the CoalVal publication manual and the CoalVal Program. The CoalVal report is divided into five specific areas relevant to the development and use of the CoalVal program: 1. Introduction to CoalVal Assumptions and Concepts. 2. Mine Model Assumption Details (appendix A). 3. CoalVal Project Tutorial (appendix B). 4. Program Description (appendix C). 5. Mine Model and Discounted Cash Flow Formulas (appendix D). The tutorial explains how to enter coal resource and quality data by mining method; program default values for production, operating, and cost variables; and ones own operating and cost variables into the program. Generated summary reports list the volume of resource in short tons available for mining, recoverable short tons by mining method; the seam or property being mined; operating cost per ton; and discounted cash flow cost per ton to mine and process the resources. Costs are calculated as loaded in a unit train, free-on-board the tipple, at a rate of return prescribed by the evaluator. The recoverable resources (in short tons) may be grouped by incremental cost over any range chosen by the user. For example, in the Gillette coalfield evaluation, the discounted cash flow mining cost (at an 8 percent rate of return) and its associated tonnage may be grouped by any applicable increment (for example, $0.10 per ton, $0.20 per ton, and so on) and using any dollar per ton range that is desired (for example, from $4.00 per ton to $15.00 per ton). This grouping ability allows the user to separate the coal reserves from the nonreserve resources and to construct cost curves to determine the effects of coal market fluctuations on the availability of coal for fuel whether for the generation of electricity or for coal-to-liquids processes. Coking coals are not addressed in this report.

Open-File Report

Mineral surveys by the Geological Survey and the Bureau of Mines of Bureau of Land Management Wilderness Study Areas

The Federal Land Policy and Management Act of 1976 instructed the Bureau of Land Management (BLM) to review all public lands under its jurisdiction and to determine their suitability or nonsuitability for wilderness designation. As part of this process, the Geological Survey and the Bureau of Mines conduct mineral surveys of areas for which a preliminary determination of wilderness suitability has been made. The BLM has completed its wilderness inventory phase and has found that 23.2 million acres deserve further study for wilderness consideration. These 23.2 million acres of wilderness study areas include 1 million acres of natural and primitive areas (Instant Study Areas), 5.7 million acres in the California Desert Conservation Area, and 16.5 million acres in other wilderness study areas. Mineral surveys on all areas recommended for wilderness will be completed by 1990.

Circular

Geology and ore deposits of the Kutam Mine, Kingdom of Saudi Arabia

The ancient Kutam mine in southwestern Saudi Arabia was discovered during the course of regional geologic mapping. Malachite coatings along fractures in the ancient workings and nearby large piles of slag indicate the mine was worked for copper. Quartz porphyry of Precambrian age is the principal host rock of the deposit. The quartz porphyry is associated with volcanic rocks of mafic to intermediate composition. All rocks have been deformed and metamorphosed to various types of schist, of which quartz-sericite-chlorite schist is the most common. Mineralization is thought to be controlled by the convergence of three fault patterns that strike N 60°W., N 45°W and N. 20°W, respectively, and dip steeply west to vertical. Cross faults that extend between faults of the N 45°W. pattern have influenced deposition of sulfides locally. Southeast-plunging lineation derived from two converging directions of planar schistosity also may have exerted control on sulfide deposition. Detailed geologic mapping of surface features and geochemical and geophysical studies indicated that the deposit warranted subsurface exploration. Accordingly, eight holes were drilled that delineated possible economic-grade sulfide deposits in an area about 300 m long and which is known to continue to a depth of more than 200 m. However, drilling found copper-zinc mineralization along a strike length of 850 m. Drill findings show that copper and zinc sulfides partially replace chlorite and higher concentrations of chlorite generally define the higher-grade mineralization. The more intensely chloritized zones tend to follow the N.45°W. fracture pattern. South of drill hole KA-I, the sulfide mineralization may plunge 40° to 60° southeast. Indicated and inferred reserves outlined by drilling total 8,056,000 metric tons, the grade of which averages 0.31 g/t Au, 6.13 g/t Ag, 1.83 percent Cu, and 0.95 percent Zn.

Open-File Report

Map of sand and gravel mines, prospects, and occurrences, and the geologic units that host them in the Wyoming Landscape Conservation Initiative (WLCI) study area, southwestern Wyoming

The Wyoming Landscape Conservation Initiative (WLCI) is a long-term science based effort to assess and enhance aquatic and terrestrial habitats at a landscape scale in southwest Wyoming, while facilitating responsible development through local collaboration and partnerships. The role of the U.S. Geological Survey is to build the scientifically defensible foundation on which WLCI planners, decisionmakers, and resource managers may base their activities. Understanding the distribution of mineral resources is integral to understanding where mineral development (mining) might be concentrated in the future and how that mining might affect habitats. This map and report focus on naturally-occurring sand and gravel, a form of construction aggregate.

Wyoming

Geology of the Shinarump No. 1 uranium mine, Seven Mile Canyon area, Grand County, Utah

The Shinarump No. 1 uranium mine is located about 12 miles northwest of Moab, Utah, in the Seven Mile Canyon area, Grand County, Utah. A study was made of the geology of the Shinarump No. 1 mine in order to determine the habits, ore controls, and possible origin of the deposit. Rocks of Permain, Triassic, and Jurassic age crop out in the area mapped. Uranium deposits are found in three zones in the lower 25 feet of the Upper Triassic Chinle formation. The Shinarump No. 1 mine, which is in the lowermost zone, is located on the west flank of the Moab anticline near the Moab fault. The Shinarump No. 1 uranium deposit consists of discontinuous lenticular layers of mineralized rock, irregular in outline, that, in general, follow the bedding. Ore minerals, mainly uranite, impregnate the rock. High-grade seams of uranite and chalcocite occur along bedding planes. Formation of unraninite is later than or simultaneous with most sulfides. Chalcocite may be of two ages, with some being later than uraninite. Uraninite and chalcocite are concentrated in the poorer sorted parts of siltstones. Guides to ore in the Seven Mile Canyon area inferred from the study of the Shinarump No. 1 deposit are the presence of bleached siltstone, copper sulfides, and carbonaceous matter. Results of spectrographic analysis indicated that the mineralizing solutions contained important amounts of barium, vanadium, uranium, and copper as well as lesser amounts of strontium, chromium, boron, yttrium, lead, and zinc. The origin of the Shinarump No. 1 deposit is thought to be hydrothermal, dated as later or early.

Utah

Presentation Showing Results of a Hydrogeochemical Investigation of the Standard Mine Vicinity, Upper Elk Creek Basin, Colorado

PREFACE This Open-File Report consists of a presentation given in Crested Butte, Colorado on December 13, 2007 to the Standard Mine Advisory Group. The presentation was paired with another presentation given by the Colorado Division of Reclamation, Mining, and Safety on the physical features and geology of the Standard Mine. The presentation in this Open-File Report summarizes the results and conclusions of a hydrogeochemical investigation of the Standard Mine performed by the U.S. Geological Survey (Manning and others, in press). The purpose of the investigation was to aid the U.S. Environmental Protection Agency in evaluating remediation options for the Standard Mine site. Additional details and supporting data related to the information in this presentation can be found in Manning and others (in press).

Open-File Report

Characterization of Geologic Structures and Host Rock Properties Relevant to the Hydrogeology of the Standard Mine in Elk Basin, Gunnison County, Colorado

The Standard Mine Superfund Site is a source of mine drainage and associated heavy metal contamination of surface and groundwaters. The site contains Tertiary polymetallic quartz veins and fault zones that host precious and base metal sulfide mineralization common in Colorado. To assist the U.S. Environmental Protection Agency in its effort to remediate mine-related contamination, we characterized geologic structures, host rocks, and their potential hydraulic properties to better understand the sources of contaminants and the local hydrogeology. Real time kinematic and handheld global positioning systems were used to locate and map precisely the geometry of the surface traces of structures and mine-related features, such as portals. New reconnaissance geologic mapping, field and x-ray diffraction mineralogy, rock sample collection, thin-section analysis, and elemental geochemical analysis were completed to characterize hydrothermal alteration, mineralization, and subsequent leaching of metallic phases. Surface and subsurface observations, fault vein and fracture network characterization, borehole geophysical logging, and mercury injection capillary entry pressure data were used to document potential controls on the hydrologic system.

Open-File Report

Description of sediment data collected by the U.S. Geological Survey in small watersheds in coal-mining areas of the eastern United States, 1980-84

Hydrologic data were collected by the U.S. Geological Survey from 20 small watersheds in the surface-mining areas of the eastern United States from 1980 through 1984 as part of the Survey1 s coal-hydrology program. Each data set includes sediment-concentration, streamflow, and precipitation data collected at 5- or 15-minute intervals. One reason for collecting the data was to test the sediment component of a watershed model. However, adequate testing requires reliable calibration data collected at several points during the rise and fall of hydrographs of several storms. Therefore, the quantity and quality of the data sets needed to be described to determine which sets could be used to test a model adequately. The data sets are described in a table that presents information about watershed characteristics, period of record, and amount of useful sediment data. Also, similar data sets collected by 10 Survey project offices during other Survey programs are described in a similar table.

Open-File Report

Mercury speciation in the Mt. Amiata mining district (Italy): interplay between urban activities and mercury contamination

A fundamental step to evaluate the biogeochemical and eco-toxicological significance of Hg dispersion in the environment is to determine speciation of Hg in solid matrices. In this study, several analytical techniques such as scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), sequential chemical extractions (SCEs), and X-ray absorption spectroscopy (XANES) were used to identify Hg compounds and Hg speciation in samples collected from the Mt. Amiata Hg mining district, southern Tuscany, Italy. Different geological materials, such as mine waste calcine (retorted ore), soil, stream sediment, and stream water suspended particulate matter were analyzed. Results show that the samples were generally composed of highly insoluble Hg compounds such as sulphides (HgS, cinnabar and metacinnabar), and more soluble Hg halides such as those associated with the mosesite group. Other moderately soluble Hg compounds, HgCl 2 , HgO and Hg 0 , were also identified in stream sediments draining the mining area. The presence of these minerals suggests active and continuous runoff of soluble Hg compounds from calcines, where such Hg compounds form during retorting, or later in secondary processes. Specifically, we suggest that, due to the proximity of Hg mines to the urban center of Abbadia San Salvatore, the influence of other anthropogenic activities was a key factor for Hg speciation, resulting in the formation of unusual Hg-minerals such as mosesite.

Tuscany

Drone-based radiometric surveys provide high-resolution mine waste characterization

Airborne radiometric surveys use passive geophysical techniques to characterize geochemical variations at or near earth’s surface. These methods have been used for a variety of mapping applications, including mineral resource evaluation. However, detailed characterization of smaller geologic targets, including mine waste features, requires flying at lower altitudes and with tighter line spacing than is feasible with traditional aircraft. Here, a small uncrewed aircraft system (sUAS) equipped with a radiometric sensor was used to acquire high-resolution gamma-spectrometry over small mine waste features and a low-grade stockpile in southwestern New Mexico. The sUAS radiometric system mapped local variability within each survey area and revealed ~2–10 m wide zones where radioelements K, Th, and U may be elevated 2–10× the surrounding material. Additionally, the sUAS radiometric data revealed radioelement variability across survey sites, which correlated reasonably well with variability seen in geochemical samples at each survey site, even though samples collected from individual sites showed high local variability. The sUAS data characterized local heterogeneity within mine waste and other small geologic targets at scales of a few meters to tens of meters, which is not possible with traditional crewed aircraft, and with continuity of coverage that is not possible with ground surveys, thus filling a key gap in geophysical survey spatial resolution.

New Mexico

Map showing potential metal-mine drainage hazards in Colorado, based on mineral-deposit geology

This map, compiled by the U.S. Geological Survey (USGS) in cooperation with the Colorado Geological Survey (CGS) and the U. S. Bureau of Land Management (BLM), shows potential mine-drainage hazards that may exist in Colorado metal-mining districts, as indicated by the geologic characteristics of the mineral deposits that occur in the respective districts. It was designed to demonstrate how geologic and geochemical information can be used on a regional scale to help assess the potential for mining-related and natural drainage problems in mining districts, unmined mineralized areas, and surrounding watersheds. The map also provides information on the distribution of different mineral deposit types across Colorado. A GIS (Geographic Information System) format was used to integrate geologic, geochemical, water-quality, climate, landuse, and ecological data from diverse sources. Likely mine-drainage signatures were defined for each mining district based on: (1) a review of the geologic characteristics of the mining district, including mineralogy, trace-element content, host-rock lithology, and wallrock alteration, and; (2) results of site specific studies on the geologic controls on mine-drainage composition.

Colorado