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.

This map is the result of field investigations by DGGS in 1997 and 1998. This geologic map and report supersede the previously released Public Data File 99-24B, Preliminary interpretive bedrock geologic map of the Healy A-6 Quadrangle, southcentral Alaska. The current map has been updated to include mapping of areas adjacent to the Healy A-6 Quadrangle, newly interpreted bedrock units based on newly acquired analytical, paleontologic, and Ar40/Ar39 data. Ages for the rock units were modified. Field investigations were part of a two-year mapping program to provide geologic ground truth for airborne geophysical surveys flown by DGGS in the Chulitna region of southcentral Alaska during 1996.

This map is the result of field investigations by DGGS in 1997 and 1998. This geologic map and report supersede the previously released Public Data File 99-24B, Preliminary interpretive bedrock geologic map of the Healy A-6 Quadrangle, southcentral Alaska. The current map has been updated to include mapping of areas adjacent to the Healy A-6 Quadrangle, newly interpreted bedrock units based on newly acquired analytical, paleontologic, and Ar40/Ar39 data. Ages for the rock units were modified. Field investigations were part of a two-year mapping program to provide geologic ground truth for airborne geophysical surveys flown by DGGS in the Chulitna region of southcentral Alaska during 1996.

Bedrock geologic map of the northern Fairbanks mining district, Circle Quadrangle, Alaska, Preliminary Interpretive Report 2022-2, presents whole-rock trace-element geochemistry of Nb, Rb, Sr, Y, Zr for samples collected to support geologic mapping and mineral exploration in the northern Fairbanks mining district. The analytical data tables associated with this report are available through the Alaska Geochemistry database (https://maps.dggs.alaska.gov/geochem). For a direct link to this data release, see http://doi.org/10.14509/30891.

Mineral Resources Section personnel from the Alaska Division of Geological & Geophysical Surveys (DGGS) carried out a geologic 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 geologic mapping. Specifically, this work provides geologic context for geophysical surveys conducted in 2006. Interpretation and synthesis of this data has been presented in professional and trade meetings. This report and associated geologic map data are preliminary, have not undergone rigorous peer review, and will be superseded by a subsequent Report of Investigations map and report that will be issued later in 2016. The objective of the eastern Bonnifield project is to produce a 1:50,000-scale geologic map to foster a better understanding of the area's geology and mineral potential. Although DGGS concentrated on mapping the Paleozoic metamorphic rocks that host the volcanogenic massive sulfide deposits (VMS) and Mesozoic igneous rocks associated with Au-Ag-As-Sb veins, we also studied the Tertiary sedimentary section, which could contain coal resources. The geologic map data are available in digital format as ESRI shapefiles.