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This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the National Fish Habitat Partnership's 2015 National Fish Habitat Asessment.
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...
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,...
This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the National Fish Habitat Partnership's national estuary assessment.
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...
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...
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,...
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,...
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.
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...
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...
Because fish reflect the quality of the habitat where they live, habitat conditions were evaluated by estimating how strongly various human habitat disturbances affect stream fish in all parts of the country. The national datasets used for this assessment included 26 variables that accounted for different human disturbances to aquatic habitats. These included: the quantity of urban, agriculture, and pasture lands in watersheds; major point-sources of water pollution; frequency of dams and road crossings throughout river networks; and intensity of mining activities in watersheds. Five natural landscape variables were also used to account for their potential influences on stream fishes. Because of broad differences...
The Regional Estuary Assessment for the northern Gulf of Mexico represents an effort to develop, test, and implement a new assessment methodology for marine habitats that improves the analytical basis for identifying impacts to estuarine fish habitats. This new regional assessment approach offers several advantages: Incorporates information on fish/shellfish presence/absence from over 70,000 sampling events collected over two decades, so we can better relate fish habitat condition to natural and anthropogenic variables. Better accounts for the high amounts of natural variation found in the marine environment, which can affect the susceptibility of individual estuaries. Allows us to take advantage of regional datasets...
The "Fish with Habitat Trouble" section of the National Fish Habitat Assessment is designed in a simple, summarized format to highlight how the impairment of fish habitat can and does directly affect fish in each region of the United States. The following considerations were taken to identify the subset of species used in the report. Initially a list of potential species for each region was developed by querying the American Fisheries Society’s Imperiled Fish database for species within each region that have a threat criteria of "1", which indicates that habitat loss is a reason the specie is imperiled. This list was verified and expanded by partner fisheries agencies and Fish Habitat Partnerships to ensure species...
On November 8, 2011, an extra-tropical cyclone with a low pressure of 945 millibars developed over the Bering Sea and moved northeast across the western coast of Alaska. This large storm brought high winds (gusts of up to 85 mph) to the entire region and a storm surge of approximately 3 meters to parts of Norton Sound. The storm caused extensive flooding in the lower portion of Golovin on the afternoon of November 9, 2011. A team of Alaska Division of Geological & Geophysical Surveys (DGGS) scientists visited Golovin on November 15, 2011, to document peak water levels, runup elevations, and inundation extents caused by this event. These data were combined with photographs taken by local residents during the event...
Community composition data from multi-pass electrofishing surveys for assessing fish populations in headwater streams of the Adirondack Mountains, New York, USA. Each row represents one individual fish. This spreadsheet contains 11 columns. The first 7 columns describe the data (year collected, local site ID, stream name, latitude, longitude, USGS site number, and electrofishing pass number) and the remaining 4 columns describe each individual fish (common name, scientific name, total length (mm) and weight (g)). These data support the following publication: Baldigo, B.P., Sporn, L.A., George, S.D., and Ball, Jacob, 2017. Efficacy of environmental DNA to detect and quantify Brook Trout Salvelinus fontinalis, populations...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Citation,
Downloadable,
Map Service;
Tags: Adirondack State Park,
Adirondack streams,
Adirondacks,
Aquatic Biology,
DNA,
A pilot study using discriminant analysis on major oxide and minor element data from 67 chert samples in the Rampart area, southeastern Tanana and southwest Livengood Quadrangles, western Yukon-Tanana Upland, Alaska, generally indicates a unique geochemical signature for the cherts of a given unit.Chert samples from five known type locales were used as standards of comparison: 1)Livengood Dome Chert (Ordovician), 2)Amy Creek unit (Proterozoic to early Paleozoic), 3)Rampart Group (Mississippian to Triassic), 4)Troublesome Creek unit (Devonian), and 5)Permian-Triassic clastic unit (associated with the Triassic-dated gabbro). Samples from the above units were compared to chert from Tanana B-1 area-units of unknown...
A new avian richness evaluation method (AREM) was developed and tested for assessing lowland wetland and riparian habitats of the Colorado Plateau. AREM rapidly scores habitats for avian richness from simple observations of habitat characteristics. AREM's predictions were compared with original field data from 76 sites on the Colorado Plateau during the breeding season. Species predictions and detections were highly indicative of the breeding avifauna in regional wetlands studied. AREM has implications for use in mitigation calculations, detection of impaired wetland quality, selection of appropriate indicator species, targeting habitat enhancements, wildlife-based classification of wetland habitats, and assisting...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Colorado,
Wildlife Society Bulletin,
birds,
diversity,
habitat assessment,
Mineral-resources personnel from the Alaska Division of Geological & Geophysical Surveys carried out a geological field survey, including mapping and sampling, in the eastern part of the Bonnifield mining district in the Fairbanks A-1 and A-2, and the Healy D-1 and D-2 quadrangles, Alaska, from June 16 through July 18, 2008. The fieldwork provides basic information critical to building an understanding of Alaska's geology and is part of an integrated program of airborne geophysical surveys followed by geological mapping. Specifically, this work provides geologic context for geophysical surveys conducted in 2006. To represent a typical lithology, igneous or possible meta-igneous samples were collected and analyzed...
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