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Mercury Contamination From Historical Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach, Jason T. May, Roger L. Hothem Jan 2005

Mercury Contamination From Historical Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach, Jason T. May, Roger L. Hothem

United States Geological Survey: Publications

Mercury contamination from historical gold mines represents a potential risk to human health and the environment. This fact sheet provides background information on the use of mercury in historical gold mining and processing operations in California, with emphasis on historical hydraulic mining areas. It also describes results of recent USGS projects that address the potential risks associated with mercury contamination.

Miners used mercury (quicksilver) to recover gold throughout the western United States. Gold deposits were either hardrock (lode, gold-quartz veins) or placer (alluvial, unconsolidated gravels). Underground methods (adits and shafts) were used to mine hardrock gold deposits. Hydraulic, drift, or …


Questa Baseline And Pre-Mining Ground- Water Quality Investigation. 5. Well Installation, Water-Level Data, And Surface- And Ground-Water Geochemistry In The Straight Creek Drainage Basin, Red River Valley, New Mexico, 2001-03, Cheryl A. Naus, R. Blaine Mccleskey, D. Kirk Nordstrom, Lisa C. Donohoe, Andrew G. Hunt, Frederick L. Paillet, Roger H. Morin, Phillip L. Verplanck Jan 2005

Questa Baseline And Pre-Mining Ground- Water Quality Investigation. 5. Well Installation, Water-Level Data, And Surface- And Ground-Water Geochemistry In The Straight Creek Drainage Basin, Red River Valley, New Mexico, 2001-03, Cheryl A. Naus, R. Blaine Mccleskey, D. Kirk Nordstrom, Lisa C. Donohoe, Andrew G. Hunt, Frederick L. Paillet, Roger H. Morin, Phillip L. Verplanck

United States Geological Survey: Publications

The U.S. Geological Survey, in cooperation with the New Mexico Environment Department, is investigating the pre-mining ground-water chemistry at the Molycorp molybdenum mine in the Red River Valley, northern New Mexico. The primary approach is to determine the processes controlling groundwater chemistry at an unmined, off-site, proximal analog. The Straight Creek drainage basin, chosen for this purpose, consists of the same quartz-sericite-pyrite altered andesitic and rhyolitic volcanic rock of Tertiary age as the mine site. The weathered and rugged volcanic bedrock surface is overlain by heterogeneous debris-flow deposits that interfinger with alluvial deposits near the confluence of Straight Creek and …


Origin Of Secondary Sulfate Minerals On Active Andesitic Stratovolcanoes, D.R. Zimbelman, Robert O. Rye, G.N. Breit Jan 2005

Origin Of Secondary Sulfate Minerals On Active Andesitic Stratovolcanoes, D.R. Zimbelman, Robert O. Rye, G.N. Breit

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Sulfate minerals in altered rocks on the upper flanks and summits of active andesitic stratovolcanoes result from multiple processes. The origin of these sulfates at five active volcanoes, Citlalte´petl (Mexico), and Mount Adams, Hood, Rainier, and Shasta (Cascade Range, USA), was investigated using field observations, petrography, mineralogy, chemical modeling, and stable-isotope data. The four general groups of sulfate minerals identified are: (1) alunite group, (2) jarosite group, (3) readily soluble Fe- and Al-hydroxysulfates, and (4) simple alkaline-earth sulfates such as anhydrite, gypsum, and barite. Generalized assemblages of spatially associated secondary minerals were recognized: (1) alunite+silica±pyrite±kaolinite±gypsum±sulfur, (2) jarosite+alunite+silica; (3) jarosite+smectite+silica±pyrite, (4) …


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


Basal Tissue Structure In The Earliest Euconodonts: Testing Hypotheses Of Developmental Plasticity In Euconodont Phylogeny, Xi-Ping Dong, Philip C. J. Donoghue, John E. Repetski Jan 2005

Basal Tissue Structure In The Earliest Euconodonts: Testing Hypotheses Of Developmental Plasticity In Euconodont Phylogeny, Xi-Ping Dong, Philip C. J. Donoghue, John E. Repetski

United States Geological Survey: Staff Publications

The hypothesis that conodonts are vertebrates rests solely on evidence of soft tissue anatomy. This has been corroborated by microstructural, topological and developmental evidence of homology between conodont and vertebrate hard tissues. However, these conclusions have been reached on the basis of evidence from highly derived euconodont taxa and the degree to which they are representative of plesiomorphic euconodonts remains an open question. Furthermore, the range of variation in tissue types comprising the euconodont basal body has been used to establish a hypothesis of developmental plasticity early in the phylogeny of the clade, and a model of diminishing potentiality in …


Hydrologic Properties Of Coal Beds In The Powder River Basin, Montana I. Geophysical Log Analysis, Roger H. Morin Jan 2005

Hydrologic Properties Of Coal Beds In The Powder River Basin, Montana I. Geophysical Log Analysis, Roger H. Morin

United States Geological Survey: Staff Publications

As part of a multidisciplinary investigation designed to assess the implications of coal-bed methane development on water resources for the Powder River Basin of southeasternMontana, six wells were drilled through Paleocene-age coal beds along a 31 km east–west transect within the TongueRiver drainage basin.Analysis of geophysical logs obtained in thesewells provides insight into the hydrostratigraphic characteristics of the coal and interbedded siliciclastic rocks and their possible interaction with the local stress field.Natural gamma and electrical resistivity logswere effective in distinguishing individual coal beds. Full-waveformsonic logswere used to determine elastic properties of the coal and an attendant estimate of aquifer storage …


Negative Correlation Between Porosity And Hydraulic Conductivity In Sand-And-Gravel Aquifers At Cape Cod, Massachusetts, Usa, Roger H. Morin Jan 2005

Negative Correlation Between Porosity And Hydraulic Conductivity In Sand-And-Gravel Aquifers At Cape Cod, Massachusetts, Usa, Roger H. Morin

United States Geological Survey: Staff Publications

Although it may be intuitive to think of the hydraulic conductivity K of unconsolidated, coarse-grained sediments as increasing monotonically with increasing porosity ɸ , studies have documented a negative correlation between these two parameters under certain grain-size distributions and packing arrangements. This is confirmed at two sites on Cape Cod, Massachusetts, USA, where groundwater investigations were conducted in sand-and-gravel aquifers specifically to examine the interdependency of several aquifer properties using measurements from four geophysical well logs. Along with K and ɸ , the electrical resistivity R0 and the natural gamma activity γ of saturated deposits were determined as functions …


Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed Jan 2005

Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Typical porphyry-type Cu–Mo mineralization occupies two connected domal centers, the eastern Pittsmont and western Anaconda domes, that predate and largely underlie the well-known, throughgoing, Main Stage polymetallic veins of Butte. Among the sulfur-bearing minerals recovered from deep drill core of this early pre-Main Stage hydrothermal assemblage are anhydrite, chalcopyrite, pyrite, and molybdenite in veinlets bordered by K-silicate alteration, and pyrite from slightly younger quartz–pyrite veinlets with dgray-sericiticT alteration selvages. The ranges of δ34S values for minerals of the K-silicate assemblage are 9.8–18.2%◦ for anhydrite (n=23 samples), 3.0%◦ to 4.7%◦ for molybdenite (n=6), 0.4%◦ to 3.4%◦ for pyrite (n=19), …


Stratigraphy Of The Volcanic Products Around Nemrut Caldera: Implications For Reconstruction Of The Caldera Formation, Özgür Karaoğlu, Yavuz Özdemi̇r, A. Ümi̇t Tolluoğlu, Mustafa Karabiyikoğlu, Onur Köse, Jean-Luc Froger Jan 2005

Stratigraphy Of The Volcanic Products Around Nemrut Caldera: Implications For Reconstruction Of The Caldera Formation, Özgür Karaoğlu, Yavuz Özdemi̇r, A. Ümi̇t Tolluoğlu, Mustafa Karabiyikoğlu, Onur Köse, Jean-Luc Froger

Turkish Journal of Earth Sciences

The volcanological development of the Nemrut stratovolcano, located near the southwestern tip of Lake Van in eastern Turkey, is subdivided into three stages: pre-caldera, post-caldera and late stages. Two ignimbrite flows have been recognized in the pre-caldera stage. The earlier of the two occurred after basaltic lavas formed along extensional fissures. The latter, which forms the main subject of this paper, was a major flow associated with the development of the Nemrut caldera. The pyroclastic deposits of the Nemrut volcano in the pre-caldera stage are divided into three phases on the basis of palaeosols that separate them. The first phase …


Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov Jan 2005

Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov

Turkish Journal of Earth Sciences

The Strandja Zone is a pre-Cenomanian orogen consisting of three tectonic units: the Veleka, Strandja and Sakar units. The first two units display very low-grade Alpine metamorphism, whereas in the Sakar unit the Triassic sediments are metamorphosed to the amphibolite facies. For years this high-grade metamorphism was enigmatic and most of the metamorphic rocks were interpreted as a reworked Precambrian crust of the Rhodope. This contribution begins with a review of the recent data about the structure and evolution of the Sakar unit. Probably the most important recent finding was the demonstration of the lack of a structural break between …


Cross Section Of The Upper Elkhorn Coal Zone Between The Mcdowell And Jenkins West Quadrangles, Bradford L. Luckett Jan 2005

Cross Section Of The Upper Elkhorn Coal Zone Between The Mcdowell And Jenkins West Quadrangles, Bradford L. Luckett

Map and Chart--KGS

This cross section shows lithic variation and coal-bed correlations for the interval between the Upper Elkhorn No. 1 and the Upper Elkhorn No. 3 ½ coals in eastern Letcher and southern Floyd Counties. It is one of a series being made to document the characteristics of the Upper Elkhorn coal zone in eastern Kentucky. The data are derived from the KGS coal borehole database, which contains records of exploration core holes supplied by coal companies. Lines on the diagram show general bed correlations and indicate places where mineable coal beds split into two or more thinner benches. The vertical alignment …


Generalized Geologic Map For Land-Use Planning: Russell County, Kentucky, T. Jeffrey Adams, Bart Davidson, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Russell County, Kentucky, T. Jeffrey Adams, Bart Davidson, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


River Basins Of Kentucky, Daniel I. Carey, Terry D. Hounshell Jan 2005

River Basins Of Kentucky, Daniel I. Carey, Terry D. Hounshell

Map and Chart--KGS

No abstract provided.


Generalized Geologic Map For Land-Use Planning: Gallatin County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer, Ken Daniels Jan 2005

Generalized Geologic Map For Land-Use Planning: Gallatin County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer, Ken Daniels

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Hancock County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Hancock County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Spencer County, Kentucky, Bart Davidson, Daniel I. Carey, Stephen F. Greb Jan 2005

Generalized Geologic Map For Land-Use Planning: Spencer County, Kentucky, Bart Davidson, Daniel I. Carey, Stephen F. Greb

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Caldwell County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Caldwell County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Garrard County, Kentucky, Bart Davidson, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Garrard County, Kentucky, Bart Davidson, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Muhlenberg County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Muhlenberg County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Estill County, Kentucky, John F. Stickney, Bart Davidson, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Estill County, Kentucky, John F. Stickney, Bart Davidson, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Wayne County, Kentucky, T. Jeffrey Adams, Bart Davidson, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Wayne County, Kentucky, T. Jeffrey Adams, Bart Davidson, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Changes In Groundwater Quality In A Conduit-Flow-Dominated Karst Aquifer As A Result Of Best Management Practices, James C. Currens Jan 2005

Changes In Groundwater Quality In A Conduit-Flow-Dominated Karst Aquifer As A Result Of Best Management Practices, James C. Currens

Report of Investigations--KGS

Water quality in the Pleasant Grove Spring karst groundwater basin was monitored to determine the effectiveness of best management practices (BMP’s) implemented through the U.S. Department of Agriculture’s Water Quality Incentive Program (WQIP). The project was divided into three phases. Phase I, beginning in August 1990, was the initial reconnaissance of the hydrogeology and water quality of the basin. Phase II, beginning in October 1993, monitored the water quality for 1 year prior to BMP implementation. This phase was followed by a 1-year interim extension, which continued the monitoring. Phase III monitored the water quality during and following BMP implementation. …


Kentucky, Kentucky Geological Survey Jan 2005

Kentucky, Kentucky Geological Survey

Map and Chart--KGS

Map showing major cities, highways, counties, and state parks in Kentucky.


Generalized Geologic Map For Land-Use Planning: Henry County, Kentucky, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Henry County, Kentucky, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Shelby County, Kentucky, Stephen F. Greb, Bart Davidson, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Shelby County, Kentucky, Stephen F. Greb, Bart Davidson, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Franklin County, Kentucky, Brandon C. Nuttall, Bart Davidson, Daniel I. Carey, Courtney Snapp Jan 2005

Generalized Geologic Map For Land-Use Planning: Franklin County, Kentucky, Brandon C. Nuttall, Bart Davidson, Daniel I. Carey, Courtney Snapp

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Kenton County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer Jan 2005

Generalized Geologic Map For Land-Use Planning: Kenton County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Groundwater Quality In Kentucky: Cadmium, Bart Davidson, R. Stephen Fisher Jan 2005

Groundwater Quality In Kentucky: Cadmium, Bart Davidson, R. Stephen Fisher

Information Circular--KGS

Cadmium is a metallic element that occurs naturally in the earth's crust, especially in zinc-, lead-, and copper-bearing ores (Forstner and Whittmann, 1981). Pure cadmium is a soft silver-white metal, but is rarely found naturally in its pure form. It is commonly combined with other elements, such as oxygen (cadmium oxide) and sulfur (cadmium sulfate).


Generalized Geologic Map For Land-Use Planning: Simpson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Simpson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Ohio County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2005

Generalized Geologic Map For Land-Use Planning: Ohio County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.