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Ramah Member of the Crevasse Canyon Formation - A new stratigraphic unit in the Zuni Basin, west-central New Mexico

Nonmarine deposition accompanying and following a regression of the Cretaceous Interior Seaway during late Turonian time left a sedimentary sequence consisting of fluvial channel sandstones, thin overbank sandstones, and paludal shales containing thin coal beds. This unit is herein designated the Ramah Member of the Crevasse Canyon Formation. The Ramah Member is locally well exposed in the Zuni Basin of west-central New Mexico where it rests on the Gallup Sandstone (marine) and is overlain by the distinctive, feldspathic Torrivio Member of the Crevasse Canyon Formation (formerly of the Gallup Sandstone) Near Ramah, New Mexico the sequence overlies the F member of the Gallup but northward it overlies progressively younger members. These younger members are discrete sand-stone units associated with minor oscillations of relative sea level during a major regional-scale regression. North and east of Puerco Gap, near Gallup. New Mexico, the Ramah Member thins appreciably, and where unmappable it may be included with the Torrivio Member Southward from Gallup in the Zuni Basin. the Ramah locally approaches 150 ft in thickness and contains minable coal beds. The interval was previously referred to as the coal-bearing member of the Gallup (Mapel and Yesberger, 1985) or the Ramah unit (Anderson and Stricker, 1904). In the northern part of the Zuni Basin a problem may exist locally in determinig the top of the Ramah Member. This is due to the presence of fluviel sandstone with coarse-grained facies that looks much the s ame as the Torrivio Member, but underlines it Two criteria may be employed to distiguish the lower sandstone from the Torrivio and properly place it in the strartigraphic succession: (1) the lower sandstone is generally not as feldspathic as the Torrivio nor do the coarse-grained facies contain pebble-size material; and (2) the lower sandstone is not nearly as widespread as the overlying Torrivio. which has a blanket geometry. The type section of the Ramah Member is in the SE1/4 NW1/4 sec. 16 T10N R16W approximately 4 mi southwest of the town of Ramah. The principal coal lies near the top of the member and was mined during the 1920s to supply coal for the Zuni Pueblo schools.

New Mexico Geology↗

Geologic map of the Myrtle Point area, Coos County, Oregon

The mapped area lies in theo southern end of the Coos Bay coal field. Coal occurs onle in the upper and lower members of the Coaledo Formation. Nearly all the coal mined in the Coos Bay coal field was from the upper member of the Coaledo Formation. In the mapped area, most of this member has been eroded; only a few hundred feed of the basal strata remains. Allen and Baldwin (1944, p. 131, 116) reported 2 feet 7 inches of coal and bone along Hall creek in the NW1/4NW1/4 sec. 11, T. 29 S., R. 13 W., and 4 feet of coal and bony coal at the Albee prospect near the center of the NE1/4 sec. 4 T. 29 S., 13 W.

Oregon↗

Reported Historic Asbestos Mines, Historic Asbestos Prospects, and Natural Asbestos Occurrences in the Southwestern United States (Arizona, Nevada, and Utah)

This map and its accompanying dataset provide information for 113 natural asbestos occurrences in the Southwestern United States (U.S.), using descriptions found in the geologic literature. Data on location, mineralogy, geology, and relevant literature for each asbestos site are provided. Using the map and digital data in this report, the user can examine the distribution of previously reported asbestos occurrences and their geological characteristics in the Southwestern U.S., which includes sites in Arizona, Nevada, and Utah. This report is part of an ongoing study by the U.S. Geological Survey to identify and map reported natural asbestos occurrences in the U.S., which thus far includes similar maps and datasets of natural asbestos occurrences within the Eastern U.S. (http://pubs.usgs.gov/of/2005/1189/), the Central U.S. (http://pubs.usgs.gov/of/2006/1211/), and the Rocky Mountain States (http://pubs.usgs.gov/of/2007/1182/. These reports are intended to provide State and local government agencies and other stakeholders with geologic information on natural occurrences of asbestos in the U.S.

Open-File Report↗

Economic effects of western Federal land-use restrictions on U.S. coal markets

Current regulations on land use in the Western United States affect access to surface minable coal resources. This U.S. Geological Survey study analyzes the long-term effects of Federal land-use restrictions on the national cost of meeting future coal demands. The analysis covers 45 years. The U.S. Bureau of Land Management has determined the environmental, aesthetic, and economic values of western Federal coal lands and has set aside certain areas from surface coal mining to protect other valued land uses, including agricultural, environmental, and aesthetic uses. Although there are benefits to preserving natural areas and to developing areas for other land uses, these restrictions produce long-term national and regional costs that have not been estimated previously. The Dynamic Coal Allocation Model integrates coal supply (coal resource tonnage and coal quality by mining cost for 60 coal supply regions) with coal demand (in 243 regions) for the entire United States. The model makes it possible to evaluate the regional economic impacts of coal supply restrictions wherever they might occur in the national coal market. The main factors that the economic methodology considers are (1) coal mining costs, (2) coal transportation costs, (3) coal flue gas desulfurization costs, (4) coal demand, (5) regulations to control sulfur dioxide discharges, and (6) specific reductions in coal availability occurring as a result of land-use restrictions. The modeling system combines these economic factors with coal deposit quantity and quality information--which is derived from the U.S. Geological Survey's National Coal Resources Data System and the U.S. Department of Energy's Demonstrated Reserve Base--to determine a balance between supply and demand so that coal is delivered at minimum cost.

Circular↗

Quality of ground water in Monitor and Williams Townships, Bay County, Michigan

Migration of mineralized water from abandoned subsurface coal mines in Monitor and Williams Townships was thought by many residents to have affected the quality of domestic ground-water supplies in the area. To investigate the possibility, wells were installed to obtain geologic data and water samples for chemical analysis; analysis also was made of concurrent related data collected by other agencies. The principal rock units are glacial deposits and the Saginaw Formation. Glacial deposits, 75 to 175 feet thick, are primarily clay underlain in places by sand and gravel. This sand and gravel is the primary source of ground water. Underlying the glacial deposits is the Saginaw Formation--a unit that is mostly shale and silty shale containing beds of siltstone, sandstone, and coal. Specific conductance of water from wells indicate that dissolved-solids concentration increases with depth. About 50 percent of specific conductance values of water from wells more than 100 feet deep were equal to or greater than 5,000 microsiemens, whereas only 13 percent of the values of water from wells less than 100 feet deep were equal to or greater than 5,000 microsiemens. Results of chemical analyses indicate no apparent correlation between concentration and source for most constituents. Plots of chloride/sulfate ratios versus specific conductances indicate that water from the Saginaw Formation is as likely to influence the quality of water in glacial deposits as is water from abandoned mines.

Michigan↗

Goat paddock cryptoexplosion crater, Western Australia

Goat Paddock, a crater slightly over 5 km in diameter (18??20??? S, 126??40???E), lies at the north edge of the King Leopold Range/Mueller Range junction in the Kimberley district, Western Australia (Fig. 1). It was noted as a geological anomaly in 1964 during regional mapping by the Bureau of Mineral Resources, Geology and Geophysics and the Geological Survey of Western Australia. The possibility of its being a meteorite impact crater has been discussed1, although this suggestion was subsequently ignored2. Two holes were drilled by a mining corporation in 1972 to test whether kimberlite underlay the structure. Here we report the findings of five days of reconnaissance in August 1979 which established that Goat Paddock is a cryptoexplosion crater containing shocked rocks and an unusually well exposed set of structural features. ?? 1980 Nature Publishing Group.

Nature↗

Alaska resource data file, Chignik quadrangle

Descriptions of the mineral occurrences can be found in the report. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: McCarthy quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: Nabesna quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: Wiseman quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: Juneau quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: Talkeetna Mountains quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

Alaska resource data file: McCarthy quadrangle

Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Alaska↗

A Sr-Nd isotopic study of sand-sized sediment provenance and transport for the San Francisco Bay coastal system

A diverse suite of geochemical tracers, including 87 Sr/ 86 Sr and 143 Nd/ 144 Nd isotope ratios, the rare earth elements (REEs), and select trace elements were used to determine sand-sized sediment provenance and transport pathways within the San Francisco Bay coastal system. This study complements a large interdisciplinary effort (Barnard et al., 2012) that seeks to better understand recent geomorphic change in a highly urbanized and dynamic estuarine-coastal setting. Sand-sized sediment provenance in this geologically complex system is important to estuarine resource managers and was assessed by examining the geographic distribution of this suite of geochemical tracers from the primary sources (fluvial and rock) throughout the bay, adjacent coast, and beaches. Due to their intrinsic geochemical nature, 143 Nd/ 144 Nd isotopic ratios provide the most resolved picture of where sediment in this system is likely sourced and how it moves through this estuarine system into the Pacific Ocean. For example, Nd isotopes confirm that the predominant source of sand-sized sediment to Suisun Bay, San Pablo Bay, and Central Bay is the Sierra Nevada Batholith via the Sacramento River, with lesser contributions from the Napa and San Joaquin Rivers. Isotopic ratios also reveal hot-spots of local sediment accumulation, such as the basalt and chert deposits around the Golden Gate Bridge and the high magnetite deposits of Ocean Beach. Sand-sized sediment that exits San Francisco Bay accumulates on the ebb-tidal delta and is in part conveyed southward by long-shore currents. Broadly, the geochemical tracers reveal a complex story of multiple sediment sources, dynamic intra-bay sediment mixing and reworking, and eventual dilution and transport by energetic marine processes. Combined geochemical results provide information on sediment movement into and through San Francisco Bay and further our understanding of how sustained anthropogenic activities which limit sediment inputs to the system (e.g., dike and dam construction) as well as those which directly remove sediments from within the Bay, such as aggregate mining and dredging, can have long-lasting effects

California↗

Geology and fluorspar deposits of the Levias-Keystone and Dike-Eaton areas, Crittenden County, Kentucky

The fault systems of the Levias-Keystone and Dike-Eaton areas, in the Kentucky-Illinois fiuorspar district, are a complex northeastward-trending sys- tem and a simple northwestward-trending system of steeply dipping normal faults, associated in part with a lamprophyre dike. Fluorspar mining started in the area about 1900 and, as of 1945, more than 200,000 tons of crude ore probably has been mined; most of the ore was from the Levias-Keystone area. A small quantity of zinc and lead ore also is present in the Dike-Eaton area. The deposits are localized along faults that displace fiat-lying or low-dipping limestones, sandstones, and shales of the Meramec and Chester series of Missis- sippian age. Movement along most of the faults was principally vertical, with displacement as much as 600 feet. Some horizontal movement occurred along at least one fault. Geologic mapping of the surface and data from underground workings have revealed 13 faults in an area of four-fifths of a square mile. Only a few of these faults are known to contain economically important deposits of fiuorspar. The most abundant vein minerals are calcite and fiuorite with subordinate quantities of sphalerite, galena, barite, and quartz. Some weathering products of sphalerite and galena are present also. The veins are dominantly calcite that contains fiuorite lenses but in places are mainly fiuorite having lesser quantities of calcite. Sphalerite- and galena-bearing deposits are present in the Dike-Eaton area. The ore bodies mainly are the result of fissure filling and replacement of calcite by fiuorite; in addition a small amount of limestone wallrock probably has been replaced. Residual concentrations of high-grade fluorspar in the overburden above faults have yielded some so-called gravel fiuorspar. The position of the veins within the faults may be related to one or more factors such as type of wallrock, change in dip of the fault, and amount of displacement.

Kentucky↗

Reported historic asbestos mines, historic asbestos prospects, and other natural occurrences of asbestos in California

The map (Plate.pdf), pamphlet (Pamphlet.pdf), and the accompanying datasets in this report provide information for 290 sites in California where asbestos occurs in natural settings, using descriptions found in the geologic literature. Data on location, mineralogy, geology, and relevant literature for each asbestos site are provided. Using the map and digital data in this report, the user can examine the distribution of previously reported asbestos and their geological characteristics in California. This report is part of an ongoing study by the U.S. Geological Survey to identify and map sites where asbestos mineralization occurs in the United States, which includes similar maps and datasets of natural asbestos localities within the Eastern United States (http://pubs.usgs.gov/of/2005/1189/), the Central United States (http://pubs.usgs.gov/of/2006/1211/), the Rocky Mountain States (http://pubs.usgs.gov/of/2007/1182/), the Southwestern United States (http://pubs.usgs.gov/of/2008/1095/), and the Northwestern United States (Oregon and Washington) (http://pubs.usgs.gov/of/2010/1041/). These reports are intended to provide State and local government agencies and other stakeholders with geologic information on reported asbestos mineralization in the United States.

California↗

Water use, availability, and net demand in the Tennessee River watershed within Alabama, 2005

The U.S. Geological Survey worked in cooperation with the Alabama Department of Economic and Community Affairs—Office of Water Resources to estimate water use and water availability for 2005 for the portion of the Tennessee River watershed contained within the borders of the State of Alabama. Estimates of water use and availability are an important part of planning for population and economic growth in the Tennessee River watershed in Alabama. Total water use for the region in 2005 was 5,197 million gallons per day (Mgal/d). Total surface-water withdrawals were 5,139 Mgal/d, and total groundwater withdrawals were about 58 Mgal/d. About 92 percent of the total water withdrawn was surface water used for once-through cooling for thermoelectric power generation. Self-supplied industrial and public-supply water uses accounted for the next greatest uses of water, constituting approximately 49 and 42 percent, respectively, of the total water use excluding thermoelectric power use. Summaries of water use by county and subbasin indicated the areas of greatest water withdrawals and use within the Tennessee River watershed. Limestone (2,012 Mgal/d), Jackson (1,498 Mgal/d), and Colbert (1,363 Mgal/d) Counties were the counties with the greatest total water use in 2005 and had large amounts of water withdrawn for thermoelectric power generation. When water use from thermoelectric power generation was not considered, the counties with the greatest withdrawals were Morgan (124 Mgal/d), Madison (72 Mgal/d), Colbert (69 Mgal/d), and Lawrence (67 Mgal/d). The subbasin with the greatest total water use was Wheeler Lake (2,260 Mgal/d) in the Middle Tennessee—Elk subregion. Wheeler Lake subbasin also had the greatest public-supply, irrigation, industrial, mining, and thermoelectric withdrawals of any subbasin in the Tennessee River watershed within Alabama. Total water availability for the Tennessee River watershed within Alabama was estimated to be 34,567 Mgal/d by the Geological Survey of Alabama. Net water demand for the watershed was calculated by subtracting the Tennessee Valley Authority estimates of return flow from water withdrawals. The net water demand was 136 Mgal/d, which is less than 1 percent of the estimated water available.

Alabama↗

Contributions to economic geology, 1902

This bulletin has been prepared primarily with a view to securing prompt publication of the economic results of investigations by the United States Geological Survey. It is designed to meet the wants of the busy man, and is so condensed that he will be able to obtain results and conclusions with a minimum expenditure of time and energy. It also affords a better idea of the work which the Survey as an organization is-carrying on for the direct advancement of mining interests throughout the country than can readily be obtained from the more voluminous reports. Should this bulletin be favorably received by those interested in the development of the mineral industries of the United States, it is proposed to publish early in each calendar year a similar bulletin containing the results of the last year's field work in economic geology. In the preparation of the present volume, promptness of publication has been made secondary only to the economic utility of the material presented. The papers included are such only as have a direct economic bearing, all questions of purely scientific interest being excluded. The papers represent three classes : (1) Preliminary discussions of the results of extended economic investigations, which will later be published by the Survey in more detailed form; (2) comparatively detailed descriptions of occurrences of economic interest, noted by geologists of the Survey in the course of their field work, but not of sufficient importance to necessitate a later and more extended description; (3) abstracts of certain economic papers which have appeared in Survey publications during the last year, chiefly such as give a general account of the distribution and mode of occurrence of particular mineral deposits throughout the United States. The papers have been grouped according to the subjects treated. At the end of each section is given a list of previous publications on that subject by this Survey. These lists will be found serviceable by those who wish to ascertain what has been accomplished by the Survey in the investigation of any particular group of mineral products. They are generally confined to Survey publications, though a few titles of important papers published elsewhere by members of the Survey are included.

Bulletin↗