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This report provides detailed (1:63,360-scale) mapping of the Tanana A-1 and A-2 quadrangles (500 square miles; equivalent to eight 7.5-minute quadrangles). The area is part of the Manley Hot Springs-Tofty mining districts and adjacent to the Rampart mining district to the south of the Tanana B-1 Quadrangle. This report includes detailed bedrock, surficial, structural, and stratigraphic data. Based on the resulting geologic maps, field investigations, and laboratory materials analyses, the report also includes derivative maps of geologic construction materials and geologic hazards. The Tanana A-1 and A-2 Quadrangles and surrounding area comprise several isolated mountainous ridges in the western Yukon-Tanana Upland...
Tags: 40Ar/39Ar, Aerial Photography, Aeromagnetic Map, Aeromagnetic Survey, Age Dates, All tags...
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the location of the drill hole. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a high-resolution digital camera on a macro stand. Each zip file, named with the drill hole identification number, contains the images for a single drill hole. In response to file size restrictions, the data were organized into two parts. The "p1" and "p2" folder designations represent parts 1 and 2. The data in each zip file...
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Kasatochi is a small, isolated island volcano in the center of the Aleutian Island chain. It consists of a roughly circular cone approximately 3 km in diameter with a lake-filled central crater that is 1.2 km in diameter and extends from the highest point on the island to sea level. The oldest unit recognized is a thick series of mid-Pleistocene glaciovolcanic deposits consisting of autobrecciated lava, lahars, and volumetrically minor lava masses that we believe to have been emplaced underneath a regional ice cap. This unit is unconformably overlain by several massive Holocene lavas, above which lies a thick sequence of latest-Holocene pyroclastic deposits likely deposited during the crater-forming eruption. The...
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This report provides detailed (1:63,360-scale) mapping of portions of U.S. Geological Survey Circle B-2 (1955), B-3 (1955), B-4 (1952), C-2 (1955), C-3 (1955), and C-4 (1952) quadrangles. The area is part of the Circle mining district and adjacent to the Fairbanks mining district. This report includes detailed geologic, structural, stratigraphic, and geochronologic data. Based on the resulting geologic maps, field investigations, and laboratory materials analyses, the project has also generated derivative maps of geologic construction materials and geologic hazards.
Tags: Aereal, Aerial Photography, Aeromagnetic Survey, Age Dates, Alaska, State of, All tags...
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This dataset is the assembled analytical results of geochemical, petrographic, and geochronologic data for samples, principally those of unmineralized Tertiary volcanic rocks, from the Tonopah, Divide, and Goldfield mining districts of west-central Nevada. Much of the data presented here for the Tonopah and Divide districts are for samples collected by Bonham and Garside (1979) during geologic mapping in and around those districts, whereas much of that for samples from the Goldfield district were obtained by Ashley (1974; 1979; 1990). Additional data were derived from samples collected between 2012–2017, as part of the U.S. Geological Survey Mineral Resources Program funded project titled: “Magmatic-tectonic history...
Categories: Data; Tags: Ar, Divide mining district, Economic Geology, Esmeralda County, Fraction Tuff, All tags...
This dataset includes photographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a high-resolution digital camera on a macro stand. Each zip file, named with the drill hole identification number, contains the images for a single drill hole. The data in each zip file is organized into a folder containing the 'RAW' unprocessed CR2 images and a folder containing processed jpg images. Folders with a "p1"...
This dataset includes photographic and micrographic images of thin sections of drill core from the Stillwater Complex, Montana, along with a shapefile representing the locations of the drill holes. The core was drilled in order to study contact-type copper and nickel sulfide mineralization in the Stillwater Complex. See data release https://doi.org/10.5066/p9w5kp8u for accompanying drill log data. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a high-resolution digital camera on a macro stand. The 4x and 10x resolution images were taken on an Olympus petrographic microscope using Stream Image Analysis Software. Each zip file, named with the drill hole identification...
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This report provides detailed (1:63,360-scale) mapping of the Tanana B-1 Quadrangle (250 square miles; equivalent to four 7.5 minute quadrangles). The area is part of the Manley Hot Springs-Tofty mining districts and adjacent to the Rampart mining district to the north of the Tanana A-1 and A-2 Quadrangles. This report includes detailed bedrock, structural, stratigraphic, and geochronologic data. Based on the resulting geologic maps, field investigations, and laboratory materials analyses, the project has also generated derivative maps of geologic construction materials and geologic hazards.
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Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Sagavanirktok B-1 Quadrangle (640 square km´┐Żequivalent to four 7.5 minute quadrangles). This mapping project reinterprets micropaleontologic correlations for 17 Sagavanirktok Quadrangle wells, and reprocesses data from the one publicly-available seismic line. Surface geologic mapping, subsurface-to-surface stratigraphic age control, and seismic framework are required to reliably decipher the complex geology of this key area of the Brooks Range. Outcrops within the Sagavanirktok B-1 Quadrangle are the closest surface expressions of Prudhoe Bay source and reservoir rocks. This study yields critical petroleum-related...
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In this study, organic petrology and Osmium isotope (187Os/188Os) stratigraphy, major and trace element, and programmed pyrolysis analysis were performed on five outcrop samples from western New York, USA. Seawater Os isotope composition is controlled by radiogenic input from weathering of the ancient land and nonradiogenic input from extraterrestrial and hydrothermal sources (Peucker-Ehrenbrink and Ravizza, 2000). Os is complexed by the organic matter present at the time of deposition without isotope fractionation. Seawater Os isotope composition is reconstructed by analysing the Os isotope composition of the organic-rich sedimentary rock (Turgeon et al., 2007). The short residence time of Os (10 – 50 kyrs) in...
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The State of Alaska Division of Geological & Geophysical Surveys (DGGS) and Division of Oil & Gas (DOG) are currently engaged in a multi-year study of the hydrocarbon potential of the Tertiary and Mesozoic strata in Cook Inlet basin. Modal analyses and routine core analyses were performed on Tertiary and Mesozoic siltstones and sandstones collected during the 2007-2010 field seasons from six geographic areas in upper and lower Cook Inlet. The reservoir quality of Cook Inlet sandstones varies widely depending on their mineralogy, geologic age, burial depth, and depositional environment. Tuxedni and Naknek sandstones have poor reservoir quality and are likely to be of equally poor quality down dip. West Foreland sandstones...
Tags: Aleutian Arc, Beluga Basin, Bluff Point, Capps Glacier, Chert, All tags...
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Here the spatial variation in Raman estimates of thermal maturity within individual organic domains from several shale geologic reference materials originating from the Boquillas, Marcellus, Niobrara, and Woodford Formations are assessed from the respective Raman response. We show that for all four shales the thermal maturity parameters extracted from Raman spectra by iterative peak fitting can vary widely across distances of ≤5 µm within the same organic domain.
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This report provides detailed (1:63,360-scale) mapping of the Tanana B-1 Quadrangle (250 square miles; equivalent to four 7.5 minute quadrangles). The area is part of the Manley Hot Springs-Tofty mining districts and adjacent to the Rampart mining district to the north of the Tanana A-1 and A-2 Quadrangles. This report includes detailed geologic, structural, stratigraphic, and geochronologic data. Based on the resulting geologic maps, field investigations, and laboratory materials analyses, the project has also generated derivative maps of geologic construction materials and geologic hazards.


map background search result map search result map Geologic map of the Tanana A-1 and A-2 quadrangles, central Alaska Petrology and reservoir potential of Tertiary and Mesozoic sandstones, Cook Inlet, Alaska: A preliminary analysis of outcrop samples collected during 2007-2010 field seasons Geology of Kasatochi volcano, Aleutian Islands, Alaska Geologic map of the Circle mining district, Alaska Geologic map of the Tanana B-1 quadrangle, central Alaska Interpretive geologic bedrock map of the Tanana B-1 Quadrangle, Central Alaska Interpretive bedrock-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska High Microscale Variability in Raman Thermal Maturity Estimates from Shale Organic Matter - Data Release Data to accompany U.S. Geological Survey Data Series 1099: Petrographic, geochemical and geochronologic data for Cenozoic volcanic rocks of the Tonopah, Divide, and Goldfield Mining Districts, Nevada Enhanced wildfire at the Frasnian-Famennian boundary and its implications for O2 level and F-F mass extinction: evidence from organic petrology and Os isotope stratigraphy Thin section images of drill core from the Chrome Lake area in the Stillwater Complex, Montana Thin section images of AMAX drill core from the Stillwater Complex, Montana Thin section images of drill core from the Chrome Lake area in the Stillwater Complex, Montana Geology of Kasatochi volcano, Aleutian Islands, Alaska Thin section images of AMAX drill core from the Stillwater Complex, Montana High Microscale Variability in Raman Thermal Maturity Estimates from Shale Organic Matter - Data Release Geologic map of the Tanana B-1 quadrangle, central Alaska Interpretive geologic bedrock map of the Tanana B-1 Quadrangle, Central Alaska Interpretive bedrock-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Enhanced wildfire at the Frasnian-Famennian boundary and its implications for O2 level and F-F mass extinction: evidence from organic petrology and Os isotope stratigraphy Data to accompany U.S. Geological Survey Data Series 1099: Petrographic, geochemical and geochronologic data for Cenozoic volcanic rocks of the Tonopah, Divide, and Goldfield Mining Districts, Nevada Geologic map of the Tanana A-1 and A-2 quadrangles, central Alaska Geologic map of the Circle mining district, Alaska Petrology and reservoir potential of Tertiary and Mesozoic sandstones, Cook Inlet, Alaska: A preliminary analysis of outcrop samples collected during 2007-2010 field seasons