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This data set maps and describes the geology of the San Bernardino Wash 7.5 minutequadrangle, Riverside County, southern California. The quadrangle, situated inJoshua Tree National Park in the eastern Transverse Ranges physiographic andstructural province, encompasses parts of the northwestern Eagle Mountains,east-central Pinto Basin, and eastern Pinto Mountains.The quadrangle is underlain by a basement terrane comprising metamorphosedProterozoic strata, Mesozoic plutonic rocks, and Jurassic and Mesozoic and (or)Cenozoic hypabyssal dikes. The basement terrane is capped by a widespread Tertiaryerosion surface preserved in remnants in the Pinto and Eagle Mountains and buriedbeneath Cenozoic deposits in Pinto Basin....
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Twenty-two igneous and metamorphic rock samples were collected in a 20-km-long swath centered on the Alaska Highway between Tetlin Junction, Alaska, and the Canada border. Igneous and metamorphic rock samples were submitted to the Apatite to Zircon, Inc. laboratory (A2Z), where zircon U-Pb age analysis, using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), was performed by Paul O'Sullivan. The 15 felsic plutonic rock samples and one gabbro sample yield Cretaceous zircon U-Pb weighted-mean ages ranging from 95.7 Ma to 106.2 Ma. Zircons from a metadiorite yield a Triassic weighted-mean age of about 241.9 Ma. Metamorphic zircons from two samples with felsic igneous protoliths yield Mississippian...
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This data set contains boundaries and tags for major geologic units in Alaska, Hawaii, Puerto Rico and the U.S. Virgin Islands. In addition to the polygons representing the areal extent of geologic units, it identifies major faults and continental glaciation in Alaska. The data depict the geology of the bedrock that lies at or near the land surface, but not the distribution of surficial materials such as soils, alluvium, and glacial deposits. This map complements the Generalized Geologic Map of the Conterminous United States by Reed and Bush. The data are generalized from a compilation prepared for use in the Geologic Map of North America, published as a paper map by the Geological Society of America and...
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The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States (https://doi.org/10.5066/F7WH2N65) represents a seamless, spatial database of 48 State geologic maps that range from 1:50,000 to 1:1,000,000 scale. A national digital geologic map database is essential in interpreting other datasets that support numerous types of national-scale studies and assessments, such as those that provide geochemistry, remote sensing, or geophysical data. The SGMC is a compilation of the individual U.S. Geological Survey releases of the Preliminary Integrated Geologic Map Databases for the United States. The SGMC geodatabase also contains updated data for seven States and seven entirely new State geologic...
Categories: Data; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: Alabama, Arizona, Arkansas, California, Colorado, All tags...
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The Fortymile electromagnetic and magnetic airborne geophysical survey data were acquired with a DIGHEM-V Electromagnetic (EM) system and a cesium magnetometer. The EM and magnetic sensors were flown at a height of 30 meters (m). In addition the survey recorded data from radar and laser altimeters, a GPS navigation system, 50/60 Hz monitors and a video camera. Flights were performed with an AS-350-B2 Squirrel helicopter at a mean terrain clearance of 60 m along N-S survey flight lines with a spacing of 400 m. Tie lines were flown perpendicular to the flight lines at intervals of approximately 4,800 m
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The Preliminary Interpretive Report 2004-3B, "Bedrock geologic map of the Livengood SW C-3 and SE C-4 quadrangles, Tolovana mining district, Alaska," is the bedrock geologic map of an approximately 123-square-mile area in the central Livengood Quadrangle, Alaska.
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This data set contains boundaries and tags for major geologic units in the conterminous United States. In addition to the polygons representing the areal extent of geologic units, it identifies boundaries of metamorphic provinces, major faults, calderas, impact structures, and generalized limits of continental glaciation. The data depict the geology of the bedrock that lies at or near the land surface, but not the distribution of surficial materials such as soils, alluvium, and glacial deposits. This is a revised version of the April 2004 data set. This map complements the Generalized Geologic Map of Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands by Reed and Bush. The data are generalized from a compilation...
Categories: Web Site; Tags: Alabama, Arizona, Arkansas, Bedrock, California, All tags...
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We report U-Pb zircon geochronology results for one metavolcanic and one metaplutonic rock sample from the Mount Hayes A-6 Quadrangle of central Alaska. These samples are representative of rock units assigned to the Clearwater terrane of Jones and others (1987), a sequence of greenschist-grade metavolcanic and metasedimentary rocks of poorly constrained age and tectonic origin. Our results indicate a crystallization age of 277.33 +/- 11.84 Ma for a felsic metavolcanic rock, and a 268.05 +/- 11.64 Ma crystallization age for a granitic metaplutonic unit intruding the former.
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Re-analyses of sample pulps and bulk rejects from historic USBM rock and heavy-mineral-concentrate samples were conducted by the Alaska Division of Geological & Geophysical Surveys (DGGS) as part of the State of Alaska's Strategic and Critical Minerals Assessment project, which is designed to evaluate Alaska's potential for these resources. The objective of this resource assessment is to expand the state's geochemical database by obtaining and publishing modern, quantitative geochemical analyses for historic USBM samples, where available. Highlights of this re-analysis project include heavy mineral concentrates with up 7,220 ppm Sn, 5,870 ppm Cr, and 17,000 ppm Mn.
Tags: Aluminum, Antimony, Arsenic, Barium, Basalt, All tags...
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This data file presents 40Ar/39Ar step-heating geochronology results for a granite sample from the Livengood mining district. The Livengood area is a historically productive placer mining area approximately 80 road miles north of Fairbanks, Alaska. This data is a component of a geologic map and accompanying report that synthesizes recently collected and previously published agency and industry geologic data in a 1:50,000-scale comprehensive geologic map to build a better understanding of the geology and mineral-resource potential of the Livengood area.
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Physical properties of geologic units are important for geophysical interpretation because they provide the tie between lithology and geophysical fields. For gravity data, the applicable physical property is bulk density, which is the overall mass per unit volume of rocks, sediments, and their pore spaces. Bulk dry density is the mass per unit volume measured when the sample is dry. Saturated density is the mass per unit volume measured when the sample is saturated with fresh water, which has a density of 1,000 kg/m^3. The two values are commonly compared in order to determine the porosity of a sample, that is, the percentage of the volume that is composed of open space. Density is commonly reported in kilograms...
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This data set contains boundaries and tags for major geologic units in Alaska, Hawaii, Puerto Rico and the U.S. Virgin Islands. In addition to the polygons representing the areal extent of geologic units, it identifies major faults and continental glaciation in Alaska. The data depict the geology of the bedrock that lies at or near the land surface, but not the distribution of surficial materials such as soils, alluvium, and glacial deposits. This map complements the Generalized Geologic Map of the Conterminous United States by Reed and Bush. The data are generalized from a compilation prepared for use in the Geologic Map of North America, published as a paper map by the Geological Society of America and to be released...
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The Tok project area is adjacent to the Delta mineral belt volcanogenic massive-sulfide (VMS) district, the Peak gold-silver-copper skarn, and structurally controlled gold and antimony mineralization in the Stibnite Creek and White Gold areas. The project area also includes the Noah prospect, an intrusion-related copper prospect. Whereas the Delta mineral belt has been extensively mapped and explored, the detailed mapping does not continue into the 2015 Tok project area. In this area, only reconnaissance mapping has been conducted. The combination of a lack of detailed mapping, the industry interest in the adjacent areas, and the geophysical data findings prompted the Alaska Division of Geological & Geophysical...
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This data set maps and describes the geology of thePorcupine Wash 7.5 minute quadrangle, Riverside County,southern California. The quadrangle, situated in JoshuaTree National Park in the eastern Transverse Rangesphysiographic and structural province, encompasses partsof the Hexie Mountains, Cottonwood Mountains, northernEagle Mountains, and south flank of Pinto Basin. It isunderlain by a basement terrane comprising Proterozoicmetamorphic rocks, Mesozoic plutonic rocks, and Mesozoicand Mesozoic or Cenozoic hypabyssal dikes. The basementterrane is capped by a widespread Tertiary erosionsurface preserved in remnants in the Eagle and CottonwoodMountains and buried beneath Cenozoic deposits in PintoBasin. Locally, Miocene...
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This data set maps and describes the geology of the Pinto Mountain 7.5 minutequadrangle, Riverside County, southern California. The quadrangle, situated inJoshua Tree National Park in the eastern Transverse Ranges physiographic andstructural province, encompasses parts of the northeastern Hexie Mountains,central Pinto Mountains, and central Pinto Basin.The quadrangle is underlain by a basement terrane comprising Proterozoicmetamorphic rocks, Mesozoic plutonic rocks, and Mesozoic and Mesozoic and (or)Cenozoic hypabyssal dikes. The basement terrane is capped by a widespreadTertiary erosion surface preserved in remnants in the Hexie and Pinto Mountainsand buried beneath Cenozoic deposits in Pinto Basin. Locally, a...


map background search result map search result map Generalized Geologic Map of the Conterminous United States Generalized Geologic Map of Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands Generalized Geologic Map of the United States Geologic map and digital database of the Porcupine Wash 7.5minute quadrangle, Riverside County, California Geologic map and digital database of the Pinto Mountain 7.5minute quadrangle, Riverside County, California Geologic map and digital database of the San Bernardino Wash7.5 minute quadrangle, Riverside County, California Physical Properties by Geologic Unit in the Southern San Luis Basin, New Mexico The State Geologic Map Compilation (SGMC) Geodatabase of the Conterminous United States Fortymile mining district electromagnetic and magnetic airborne geophysical survey, data compilation Bedrock geologic map of the Livengood SW C-3 and SE C-4 quadrangles, Tolovana mining district, Alaska Analyses of historic U.S. Bureau of Mines rock and heavy mineral concentrate samples for geochemical trace-element and rare-earth element data--Ray Mountains and Kanuti-Hodzana uplands area, Alaska Zircon U-Pb age data, Alaska Highway Corridor, Tanacross and Nabesna quadrangles, Alaska Major-oxide and trace-element geochemical data from rocks collected in 2015 in the Tok area, Tanacross A-5, A-6, and parts of adjacent quadrangles, Alaska U-Pb zircon age data from meta-igneous rocks in the Clearwater Mountains, Mount Hayes A-6 Quadrangle, Alaska Geologic map of portions of the Livengood B-3, B-4, C-3, and C-4 quadrangles, Tolovana mining district, Alaska U-Pb zircon age data from meta-igneous rocks in the Clearwater Mountains, Mount Hayes A-6 Quadrangle, Alaska Geologic map and digital database of the Porcupine Wash 7.5minute quadrangle, Riverside County, California Geologic map and digital database of the Pinto Mountain 7.5minute quadrangle, Riverside County, California Geologic map and digital database of the San Bernardino Wash7.5 minute quadrangle, Riverside County, California Bedrock geologic map of the Livengood SW C-3 and SE C-4 quadrangles, Tolovana mining district, Alaska Fortymile mining district electromagnetic and magnetic airborne geophysical survey, data compilation Analyses of historic U.S. Bureau of Mines rock and heavy mineral concentrate samples for geochemical trace-element and rare-earth element data--Ray Mountains and Kanuti-Hodzana uplands area, Alaska Physical Properties by Geologic Unit in the Southern San Luis Basin, New Mexico Zircon U-Pb age data, Alaska Highway Corridor, Tanacross and Nabesna quadrangles, Alaska Generalized Geologic Map of the Conterminous United States The State Geologic Map Compilation (SGMC) Geodatabase of the Conterminous United States Generalized Geologic Map of Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands Generalized Geologic Map of the United States