Geologic map geodatabase depicting the surficial geology of the central Brooks Range, Alaska. Including the 250k quadrangles of Ambler River, Bettles, Chandalar, Chandler Lake, Hughes, Howard Pass, Killik River, Phillip Smith Mountains, Survey Pass, and Wiseman. Database tables include geologic linework and geologic units.

This map shows the distribution of unconsolidated deposits and undifferentiated bedrock exposed at the surface in the Sagavanirktok A-3, A-4, B-3, B-4, and portions of the Sagavanirktok A-5 and B-5 quadrangles. Units were mapped by interpretation of stereo pairs of approximately 1:65,000-scale false-color infrared aerial photographs taken in June and August 1978, as well as 2.5 m and 10 m resolution SPOT imagery collected in 2009 and 2010. Fieldwork was completed in 2008.

This dataset represents a digitized version of the Rawlinson 1993 surficial geologic map of the Flaxman Island and Beechy Point quadrangles, and portions of the Mount Michelson and Harrison Bay quadrangles at 1:63,360 scale. In this newly digitized version of the map, the original maps were scanned, georeferenced, and projected into GIS. Approximately 100-200 typographic and labelling errors from the paper version were corrected with inputs from the original author (corrections completed in 2024). However, this digitized product still adheres to the 1993 interpretation of the surficial geology. Original descriptions of the map units can be found with the 1993 publication (https://doi.org/10.14509/2484). The original 1993 map was generated via photointerpretation done manually on acetate sheets overlain on color infrared aerial photographs, aided by a stereoscope, and then manually transferred to a map base using a zoom-transfer scope. Only low-resolution 1:250,000-scale black-and-white Landsat imagery was available for reference in the 1980s when the mapping was completed. After photointerpretation, the surficial geology units and morphology information was field spot-checked, with extensive fieldwork occurring between 1981 and 1985. As part of the fieldwork, locations with exposure along coasts, rivers, and gravel pits were prioritized, with 464 stratigraphic sections measured and described, and 678 samples collected for analyses that included grain size, radiocarbon and thermoluminescence dating, amino acid analysis in mollusk shells and wood, identification of wood types, and microfossil and pollen contents. An important note of caution to users is that this digitized product represents the 1993 interpretation of surficial geology. Modifications to the 1993 product address typographic errors and do not consider re-interpretations of the surficial geological units since then, and more recent information about the regional surficial geology is available.

This dataset represents a digitized version of the Rawlinson 1993 surficial geologic map of the Flaxman Island and Beechy Point quadrangles, and portions of the Mount Michelson and Harrison Bay quadrangles at 1:63,360 scale. In this newly digitized version of the map, the original maps were scanned, georeferenced, and projected into GIS. Approximately 100-200 typographic and labelling errors from the paper version were corrected with inputs from the original author (corrections completed in 2024). However, this digitized product still adheres to the 1993 interpretation of the surficial geology. Original descriptions of the map units can be found with the 1993 publication (https://doi.org/10.14509/2484). The original 1993 map was generated via photointerpretation done manually on acetate sheets overlain on color infrared aerial photographs, aided by a stereoscope, and then manually transferred to a map base using a zoom-transfer scope. Only low-resolution 1:250,000-scale black-and-white Landsat imagery was available for reference in the 1980s when the mapping was completed. After photointerpretation, the surficial geology units and morphology information was field spot-checked, with extensive fieldwork occurring between 1981 and 1985. As part of the fieldwork, locations with exposure along coasts, rivers, and gravel pits were prioritized, with 464 stratigraphic sections measured and described, and 678 samples collected for analyses that included grain size, radiocarbon and thermoluminescence dating, amino acid analysis in mollusk shells and wood, identification of wood types, and microfossil and pollen contents. An important note of caution to users is that this digitized product represents the 1993 interpretation of surficial geology. Modifications to the 1993 product address typographic errors and do not consider re-interpretations of the surficial geological units since then, and more recent information about the regional surficial geology is available.

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 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 information from these surface exposures, and how they relate to the area subsurface stratigraphy.

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.

This report provides detailed (1:63,360-scale) surficial-geologic mapping in the Dalton Highway area, from the Sagavanirktok to the Itkillik Rivers, in the west-central Philip Smith Mountains quadrangle. The map area extends from the northern flank of the Endicott Mountains into the Arctic Foothills province.