Mineral-resources personnel from the Alaska Division of Geological & Geophysical Surveys carried out a geological field survey, including mapping and sampling northeast of Fairbanks in the Circle A-4, A-5, B-4, and B-5 quadrangles, Alaska from May 31 to June 28, 2007. The fieldwork provides basic information critical to building an understanding of Alaska geology and is part of an integrated program of airborne geophysical surveys followed by geological mapping. During 2007, 128 rock samples were collected for geochemical trace-element analysis, and 44 rock samples were collected for whole rock (major- and minor-oxide) analysis. Petrogenetically important trace-elements will be analyzed in a subsequent study to be published with the final map and report for this area. In addition, 67 stream sediment samples were collected for geochemical trace-element analysis. The stream sediment geochemical study was conducted over the proposed Mount Ryan Remote Recreational Cabin Staking Area as considered by Alaska's Division of Mining, Land & Water in 2007.

Mineral-resources personnel from the Alaska Division of Geological & Geophysical Surveys carried out a geological field survey, including mapping and sampling near Livengood in the Livengood B-3 and B-4 quadrangles, Alaska from June 10 to June 30, 2010. 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. During 2010, 130 rock samples were collected for geochemical trace-element analysis, and 20 rock samples were collected for whole rock (major- and minor-oxide) analysis. Petrogenetically important trace elements for additional rock samples will be analyzed and published with the final map and report for this area.

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 for major- and minor-oxide and petrogenetically important trace elements as a supplement to previously published geochemical data. The analyses were used to determine composition of the samples as well as potential original tectonic setting. Radiometric age analyses from some of these rocks have been published. Interpretation and synthesis of this data has been presented in professional and trade meetings. The analytical tables associated with this data release are available in digital format as comma-separated value (CSV) files.

Alaska Division of Geological & Geophysical Surveys (DGGS) personnel collected rock samples while mapping the bedrock geology along a 12-mile-wide swath following the Alaska Highway between Delta Junction and the eastern edge of the Mount Hayes quadrangle near Dot Lake, Alaska. This mapping is one component of the multi-year DGGS project studying the geology, geohazards and resources along the proposed gas pipeline corridor from Delta Junction to the Canadian border. In 2006, we collected 10 samples for whole rock (major- and minor-oxides, and petrogenetically important trace-elements) analysis. In 2007, we collected 111 samples for whole rock analysis and 36 rock samples for geochemical trace-element analysis. Analytical data from these rock samples are tabulated in this publication.

The Iniskin-Tuxedni Bay area contains excellent exposures of nearly all of the lower Cook Inlet Mesozoic succession, including most of the stratigraphic sections that define the interval and the petroleum source rocks that comprise the basin. An underdeveloped understanding of the Mesozoic petroleum system has led the Alaska Department of Natural Resources' Division of Geological & Geophysical Surveys and Division of Oil and Gas, and the U.S. Geological Survey to collaborate on a multi-year project that includes two major mapping campaigns. Geologic mapping between Chinitna Bay and the Johnson River during the 2015 field season encompassed volcanic arc rocks northwest of the Bruin Bay fault system, and Mesozoic forearc basin stratigraphy extending to the Cook Inlet coast. To understand and represent the complexity of the volcanic arc systems in the region, we analyzed ten samples of volcanic rocks, two samples of gabbro sill, and one mafic dike sample for major and minor oxides and trace elements. Although mineralization was not noted in the samples collected for major oxide analysis, findings of interest include: one sample with weak Cr and Ni enrichment, three samples with lightly elevated As, and slight S anomalies (0.37 wt percent and 0.25 wt percent) in samples described as Talkeetna Formation. The Talkeetna Formation sample with 0.37 wt percent S also had elevated Cu (321 ppm) and As (58 ppm). The analytical data tables associated with this report are available in digital format as comma-separated values (CSV) file.

Geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) and the University of Alaska Fairbanks (UAF) carried out geologic field surveys, including bedrock mapping and sampling, in the Alaska Highway Corridor from 2006 through 2010. The fieldwork provides basic information critical to building an understanding of Alaska's geology and is part of a broader, integrated program that includes airborne geophysical surveys, bedrock and surficial mapping, a mineral-resource assessment, a geologic-hazards assessment, and other geological studies. This publication contains descriptive, location, and analytical information for samples collected in the Mount Hayes, Tanacross, and Nabesna quadrangles, Alaska, in the summers of 2006, 2008, 2009, and 2010. Additional analytical data for samples collected in the Mount Hayes Quadrangle in the summers of 2006 and 2007 were published in a separate report. During the field seasons covered by this report, rock samples were collected for geochemical trace-element and whole-rock (major- and minor-oxide and petrogenetically important trace-element) analyses. Rock sample location coordinates are presented in decimal degree latitude and longitude based on the North American Datum of 1927 (NAD 27) for Alaska. Brief sample descriptions are based principally on field observations with some thin-section details added.

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, A-2, Healy D-1 and D-2 quadrangles, Alaska from June 16 to July 18, 2008. The fieldwork provides basic information critical to building an understanding of Alaska geology and is part of an integrated program of airborne geophysical surveys followed by geological mapping. During 2008, 242 rock samples were collected for geochemical trace-element analysis, 106 rock samples were collected for whole rock (major- and minor-oxide and petrogenetically important trace element) analyses, and 7 samples were collected for analysis of non-carbonate carbon content.

Geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) and University of Alaska carried out a two-part geologic mapping and geochemical sampling project in the Tok River area of the Tanacross A-5 and A-6 quadrangles (June 12-26 and July 8-26). The Tok River area is adjacent to the Delta mineral belt volcanogenic massive-sulfide (VMS) district, the Peak gold-silver-copper skarn, and the structurally controlled gold and antimony mineralization in the Stibnite Creek and White Gold areas. The Tok River project area includes the Noah (also called Hona) prospect, an intrusion-related copper prospect. The combination of insufficient detailed geologic mapping, historical and current industry interest in the adjacent mineralized areas, and the recently published geophysical data prompted the DGGS Mineral Resources section to work in this area. Highlights of this DGGS Tok River geochemical report include identification, sampling, and characterization of prospects without previously available public data, including the Eagle, Dall, Parton, and Jacqueline prospects. This dataset has 22 samples with gold in excess of 0.5 ppm in several different locations, including a sample with 9.78 ppm Au (16ET254, Shalovsky vein), a sample with 6.25 ppm Au from nearby Hona porphyry (16ET312), a sample containing 1.22 ppm Au from a vein within schist south of Dry Tok Creek (16KS255), and a sample with 1.315 ppm Au from drill hole WG-11-05 (16RN165B, Eagle trend). Major- and trace-element geochemical analyses were obtained for the metamorphic rocks to distinguish between igneous and sedimentary protoliths and for igneous rocks to characterize and differentiate Mesozoic and Cenozoic rocks in the area.