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This Division of Geological & Geophysical Surveys (DGGS) Raw Data File presents U-Pb geochronology and Lu-Hf isotopic compositions, age-dating results, and additional trace-elemental composition of zircons from four granitoids sampled during investigations by DGGS geologists in the western Alaska Range and the Talkeetna Mountains. The purpose of the Lu-Hf and U-Pb isotopic study was to better understand the Jurassic through early Tertiary magmatic and tectonic evolution of the Alaska Range and the significance of that magmatism for the formation of metallic mineral deposits. The U-Pb isotopic data also serve to further refine the crystallization age of plutons, which were previously ambiguous in 40Ar/39Ar geochronology...
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The State of Alaska Division of Geological & Geophysical Surveys (DGGS) produced a digital surface model (DSM) and an orthorectified aerial optical image mosaic (orthoimagery) of the Resurrection Bay watershed, surrounding the city of Seward in south-central Alaska. Aerial photographs and Global Navigation Satellite System (GNSS) data were collected on August 13, 2015, and were processed using Structure-from-Motion (SfM) photogrammetric techniques to create the DSM and orthoimagery. All data are projected in UTM Zone 6 North (meters) using the NAD83 (2011; EPSG 26906) horizontal datum and NAVD88 (Geoid12A; EPOCH 2010.00) vertical datum. The project was part of an ongoing investigation of the impact of flooding,...
Tags: Aerial, Bear Creek, Bear Lake, Bear Lake Glacier, Bear Mountain, All tags...
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The 1:63,360 Kavik River geologic map area consists of ~620 square miles and ties together previous DGGS mapping in the Sadlerochit and Shublik Mountains area of the western Arctic National Wildlife Refuge (ANWR) on the east and the structurally complex foothills and mountain front near the Kemik gas accumulation on the west. The map area exposes a unique intersection of North Slope stratigraphy where all three major depositional megasequences are mappable in close association (Ellesmerian, Beaufortian, and Brookian).
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This map shows the subcrop pattern of the Mesozoic rock units present at the top Mesozoic unconformity (also commonly referred to as the base Tertiary unconformity) in Cook Inlet basin, Alaska. The subcrop is projected onto the top Mesozoic unconformity depth surface of Cook Inlet basin, Alaska, published by Shellenbaum and others (2010). Publicly available geologic and geophysical data from multiple sources were collected, interpreted, and integrated into the subcrop map. Formation picks at the top Mesozoic unconformity were determined for 109 wells. Mesozoic horizons from two regional marine two-dimensional (2-D) seismic datasets (approximately 3,300 miles) were interpreted. Eight map units were established for...
Tags: Anchorage, Anchorage Quadrangle, Bedrock Geologic Map, Bedrock Geology, Bibliography, All tags...
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In this report, we evaluate potential tsunami hazards for the southeastern Alaska community of Juneau and numerically model the extent of inundation from tsunami waves generated by tectonic and submarine landslide sources. We calibrate our tsunami model by numerically simulating the 2011 Tohoku tsunami at Juneau and comparing our results to instrument records. Analysis of calculated and observed water level dynamics for the 2011 event in Juneau reveals that the model underestimates the observed wave heights in the city by a factor of two, likely due to complex tsunami-tide interactions. We compensate for this numerical underestimation by doubling the coseismic slip of the hypothetical tsunami sources in our models....
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During 2004 and 2005 DGGS Energy Section geologists, together with University of Alaska Fairbanks and USGS personnel, conducted 1:63,360-scale geologic mapping in the Siksikpuk River Area of the Chandler Lake B-4 and C-4 quadrangles in northern Alaska. This work was conducted as part of the USGS-funded STATEMAP project, part of the National Cooperative Geologic Mapping Program.
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Aerial photographs of the coastline from Wales to Teller were collected on August 27, 2015 - August 28, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. Orthoimages contain 4-band, 8-bit, unsigned raster data (red/green/blue/no data; file format-GeoTIFF; source-Fairbanks Fodar) with 20 cm GSD. No-data values are found...
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The State of Alaska's Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska's statewide potential for strategic and critical mineral resources. The SCM Assessment project is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. For the geochemical part of the SCM Assessment project, thousands of geochemical-sample analyses and locations from historical U.S. Bureau of Mines (USBM), U.S. Geological Survey (USGS), Bureau of Land Management (BLM), DGGS, Alaska Territorial Department of Mines, Alaska Division of Mines and...
Tags: Alaska Statewide Quadrangle, Alaska, State of, Analyses, Analyses and Sampling, Analytical Lab Results, All tags...
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During the 2017 field season, geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) conducted geologic mapping and sampling of part of the Richardson Mining District southeast of Fairbanks, including parts of the Big Delta B-4, B-5, and C-5 quadrangles. The project area is about 30 miles west of the Pogo gold mine and covers the currently active Montecristo and Uncle Sam gold-exploration properties. The goal of DGGS's work in this area is to conduct a mineral-resource assessment and to build an improved understanding of the area's geology and controls on gold mineralization to facilitate industry exploration targeting. This report is based on 17 days of fieldwork completed June 23-July 3,...
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The State of Alaska Division of Geological & Geophysical Surveys (DGGS) produced a digital surface model (DSM) and an orthorectified aerial optical image mosaic (orthoimagery) of the Resurrection Bay watershed, surrounding the city of Seward in south-central Alaska. Aerial photographs and Global Navigation Satellite System (GNSS) data were collected on August 13, 2015, and were processed using Structure-from-Motion (SfM) photogrammetric techniques to create the DSM and orthoimagery. All data are projected in UTM Zone 6 North (meters) using the NAD83 (2011; EPSG 26906) horizontal datum and NAVD88 (Geoid12A; EPOCH 2010.00) vertical datum. The project was part of an ongoing investigation of the impact of flooding,...
Tags: Aerial, Bear Creek, Bear Lake, Bear Lake Glacier, Bear Mountain, All tags...
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The Water Resources Data System is a clearinghouse of hydrological and climatological data for the State of Wyoming. The Image Mapping Service for the Powder River Basin water resource data can display information by geologic column, geologic cross section, retrieve water surface points by HUC, and retrieve points by township and range.
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This data release presents 40Ar/39Ar step-heating geochronology results from rocks collected roughly 7 km southwest of Contact Point, Iliamna B-3 Quadrangle. Samples obtained from a felsic dike intruding the principal Bruin Bay fault plane near Contact Point produced biotite and plagioclase 40Ar/39Ar ages of 36.5 +/- 0.8 Ma and 31.5+/-0.7 Ma, respectively. The age dates inform stratigraphic, structural, and geochronologic studies along the western margin of lower Cook Inlet basin. The accompanying report also presents zircon U-Pb LA-ICP-MS geochronology results for dikes near Ursus Head.
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Aerial photographs of the coastline from Wales to Teller were collected on August 27, 2015 - August 28, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. This file is a single-band, 32-bit float DSM (digital surface model) which represents surface elevations of buildings, vegetation, and uncovered ground surfaces in meters...
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Aerial photographs of the coastline from Nome to Elim were collected on August 23, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. Orthoimages contain 4-band, 8-bit, unsigned raster data (red/green/blue/no data; file format-GeoTIFF; source-Fairbanks Fodar) with 20 cm GSD. No-data values are found in band 4 or shown as...
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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.
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Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential potential tsunami hazard for the communities of Kodiak, Womens Bay, and for the U.S. Coast Guard base on Kodiak Island by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquake sources. Worst-case hypothetical scenarios are defined by analyzing results of a sensitivity study of the tsunami dynamics related to various slip distributions along the Alaska-Aleutian megathrust. The worst-case scenarios for the Kodiak communities are thought to be the subduction zone earthquakes offshore Kodiak Island with their greatest slip at 5-35 km (3.1-22...
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Declining groundwater levels in the Hueco Bolson have raised concerns about the amount of available groundwater and the potential for water-quality changes. Fresh groundwater stored in the aquifer is bordered by regions of brackish-to-saline groundwater, and as the water levels in the Hueco Bolson have declined the local and regional hydraulic gradients have been altered such that the brackish-to-saline groundwater regions have encroached upon and degraded the quality of the freshwater zones (Hibbs 1999; Heywood and Yager, 2003). To help delineate the freshwater and saline groundwater transition zone, 20 time-domain electromagnetic soundings were collected to provide resistivity structure data in the area. This...
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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�equivalent to four 7.5 minute quadrangles). This geologic map was produced by merging a bedrock geologic map and a surficial geologic map of the Eagle A-2 Quadrangle. 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...
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This publication provides mercury injection capillary pressure (MICP) data for 36 outcrop samples collected from the Kaguyak, Naknek, and West Foreland formations in the Iniskin Peninsula region of Cook Inlet. The publication files provide: sample names, coordinates, and the formation from which samples were collected; per-sample pore aperture size distribution charts; formation pore volume graphs and data; pore system properties of each formation from which samples were analyzed; and correspondence from PetroTech Associates describing the methods used in MICP analyses of the samples, and a brief summary of the data


map background search result map search result map Image Mapping Service for the Powder River Basin Wyoming Geologic Map of the Siksikpuk River Area, Chandler Lake Quadrangle, Alaska Mercury injection capillary pressure results from outcrop samples in the Kaguyak, Naknek, and West Foreland formations, Iniskin Peninsula region, Alaska Digital compilation of geochemical data for historical samples from occurrences of strategic and critical elements in Alaska: Part II - Platinum group elements (PGE) U-Pb and Lu-Hf isotope, age, and trace-element data from zircons at four sites in the western Alaska Range and Talkeetna Mountains, Alaska Zircon U-Pb and 40Ar/39Ar results from dikes collected within the Bruin Bay fault zone, lower Cook Inlet Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment A: Wales to Teller Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment A: Wales to Teller Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment C: Nome to Elim Major-oxide and trace-element geochemical data from rocks collected in the Richardson mining district, Big Delta Quadrangle, Alaska Photogrammetry-derived digital surface model and orthoimagery of land areas near Resurrection Bay, Alaska Photogrammetry-derived digital surface model and orthoimagery of land areas near Resurrection Bay, Alaska Geologic map of the Tanana B-1 quadrangle, central Alaska Geological map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Geologic map of the Kavik River area, northeastern Brooks Range, Alaska Top Mesozoic unconformity subcrop map, Cook Inlet basin, Alaska Updated tsunami inundation maps of the Kodiak area, Alaska Tsunami inundation maps for Juneau, Alaska Time-Domain Electromagnetic Data Used in the Assessment of the Freshwater/Saline-Water Transition Zone within the Hueco Bolson, Fort Bliss Area, El Paso, Texas 2017-2019 Geologic faults in the So. Wasatch Plateau study area (wsfltg) Time-Domain Electromagnetic Data Used in the Assessment of the Freshwater/Saline-Water Transition Zone within the Hueco Bolson, Fort Bliss Area, El Paso, Texas 2017-2019 Updated tsunami inundation maps of the Kodiak area, Alaska Photogrammetry-derived digital surface model and orthoimagery of land areas near Resurrection Bay, Alaska Photogrammetry-derived digital surface model and orthoimagery of land areas near Resurrection Bay, Alaska Mercury injection capillary pressure results from outcrop samples in the Kaguyak, Naknek, and West Foreland formations, Iniskin Peninsula region, Alaska Major-oxide and trace-element geochemical data from rocks collected in the Richardson mining district, Big Delta Quadrangle, Alaska Geologic map of the Tanana B-1 quadrangle, central Alaska Geological map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Geologic faults in the So. Wasatch Plateau study area (wsfltg) Geologic Map of the Siksikpuk River Area, Chandler Lake Quadrangle, Alaska Tsunami inundation maps for Juneau, Alaska Geologic map of the Kavik River area, northeastern Brooks Range, Alaska Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment A: Wales to Teller Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment A: Wales to Teller Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment C: Nome to Elim U-Pb and Lu-Hf isotope, age, and trace-element data from zircons at four sites in the western Alaska Range and Talkeetna Mountains, Alaska Top Mesozoic unconformity subcrop map, Cook Inlet basin, Alaska Image Mapping Service for the Powder River Basin Wyoming Digital compilation of geochemical data for historical samples from occurrences of strategic and critical elements in Alaska: Part II - Platinum group elements (PGE)