Geophysics - Current and Recent Projects
DGGS is geophysically surveying 989 square miles in an area centered roughly 35 miles west-southwest of Tok in the Mt. Hayes, Tanacross, Gulkana, and Nabesna quadrangles. Most of the area surveyed is in the Tok mining district; a minor portion is in the Chistochina district. The Tok survey area is bordered by two previous airborne-geophysical surveys: the 2006 Alaska Highway Corridor, and 2008 Slate Creek-Slana River surveys. The area is a mixture of State-owned and -selected land, Native-owned land, and Federally-owned land. Geophysical Report 2015-2 is now available to download for free at http://dx.doi.org/10.14509/29347.
DGGS has published data from the 2014 Tonsina electromagnetic and magnetic geophysical survey, which covers approximately 690 square kilometers of the Valdez Quadrangle with high-quality, 400-meter-line-spacing data. The survey area is approximately 80 kilometers northeast of Valdez and 40 kilometers south of Glennallen in the Nelchina mining district. The new publication, Geophysical Report 2015-1, makes 2014 Tonsina electromagnetic and magnetic geophysical survey data available to download for free at http://dx.doi.org/10.14509/29169.
Iron Creek data compliation
DGGS issued a new publication updating the 1997 Iron Creek electromagnetic and magnetic geophysical survey. The Iron Creek survey area covers approximately 1,766 square kilometers of the Talkeetna Mountains Quadrangle and the new report provides high-quality 400-meter-line-spacing data. The survey area is approximately 40 kilometers east of Talkeetna in parts of the Yentna-Cache Creek and Valdez Creek mining districts. Geophysical Report 2014-6 combines, updates, and makes a significant portion of the 1997 Iron Creek electromagnetic and magnetic geophysical survey data available for free. The majority of these data were only available at the DGGS office, by mail order, or in paper format for a fee.
The airborne geophysical survey data and maps has been released for the complete 954-square-mile Farewell survey, which is centered about 160 miles north-northwest of Anchorage in the McGrath mining district. Data acquisition for the Farewell survey was completed in summer 2013. A small subset of the Farewell survey, the 100-square-mile Dalzell Creek area, was acquired in 2012, and these data were released in October 2013. The Dalzell Creek data have now been merged with the surrounding data from the rest of the Farewell survey. Digital files of the data and maps are available here as well as DVD and paper formats at the DGGS office.
DGGS geophysically surveyed 1,060 square miles in the northwestern Tyonek, southwestern Talkeetna, and eastern Lime Hills quadrangles in 2013 and 2014. The East Styx survey is centered about 95 miles northwest of Anchorage and is adjacent to the Styx River survey released in 2008. The East Styx area is State-owned land and is mostly in the Yentna mining district. Aeromagnetic, electromagnetic, and radiometric data were acquired, and the data were released in November 2014. A later publication will contain merged aeromagnetic and merged resistivity grids for the East Styx, Styx River, and Farewell surveys.
The aeromagnetic and electromagnetic geophysical survey data has been released for the 1,322-square-mile Wrangellia survey in the Talkeetna Mountains, Healy, and Mt. Hayes quadrangles. The new survey is adjacent to previous airborne-geophysical Iron Creek, Valdez Creek, and Southern Delta River surveys. The survey area is located in the Valdez Creek and Delta River mining districts, about 150 miles north-northeast of Anchorage and roughly centered on the Denali Highway crossing of the Susitna River. DGGS completed the data acquisition in 2013. Digital files of the data and maps are available here as well as DVD and paper formats at the DGGS office. A second publication, containing a project report, interpretation, and electromagnetic anomalies, is expected to be released in 2015.