New geophysical maps and data available for Farewell Area
FAIRBANKS, Alaska – The Division of Geological & Geophysical Surveys today is releasing airborne geophysical survey data and maps for two subsets of its almost 1,300-square mile Farewell survey, centered approximately 160 miles north–northwest of Anchorage. DGGS completed the data acquisition for these subsets in 2012 and collected additional data for the remaining part of the Farewell survey in summer 2013; these remaining data will be released in 2014. The Farewell survey and its subsets, the 138-square mile Middle Styx and the 100-square mile Dalzell Creek areas, are located in the McGrath mining district.
The Farewell survey data is expected to be useful for resource exploration, planning, and public land-use management. Airborne geophysics helps to characterize bedrock types, project geology between sparse outcrops, and identify vegetation-covered, anomalous geophysical signatures that might be associated with lode mineralization.
Miners in the McGrath mining district have produced more than 300,000 troy ounces of gold since record keeping began in 1880. Much of the area is covered by surface deposits and vegetation and it has not been explored thoroughly. The Farewell survey area contains prospects representing several different mineral deposit types, including polymetallic veins, epithermal veins, porphyry copper-gold deposits, and platinum-group elements. Rare-earth-element-bearing minerals are also present in some of the granitic rocks. The Dalzell area has several known polymetallic vein occurrences, and the Middle Styx area is thought to have the potential for polymetallic veins, epithermal veins, and porphyry copper deposits.
Funding for the surveys was provided by the Alaska Legislature as part of a Strategic and Critical Mineral Capital Improvement Project and the surveys are conducted through the division’s Airborne Geophysical/Geological Mineral Inventory (AGGMI) program.
The aeromagnetic, electromagnetic, and radiometric geophysical survey data will be released in DVD and paper formats at 4 p.m. on Thursday, Oct. 31 at the DGGS office, located at 3354 College Road in Fairbanks, Alaska 99709-3707. Also at 4 p.m., digital files of the data and maps will be available at no cost on the division’s website at www.dggs.alaska.gov. The data and maps can be found through links provided on the order forms on the website. Electromagnetic-anomaly maps and an interpretive project report will be available at a later date.
DVDs and the individual map sheets are available for the cost of reproduction and can be inspected and purchased at the DGGS office. Call 907-451-5020 to place phone orders. Mail orders should be sent to the DGGS office at the above address or via fax (907-451-5050) or e-mail (firstname.lastname@example.org). Location maps and order forms are available on the DGGS website:
Middle Styx order form: http://www.dggs.alaska.gov/pubs/project-orderform/1086
Dalzell Creek order form: http://www.dggs.alaska.gov/pubs/project-orderform/1110
These materials also will be available for inspection beginning Nov. 20 at the Alaska Resources Library and Information Services (ARLIS), located at 3211 Providence Drive, Anchorage, AK 99508 (907-272-7547), and at the Historical Collection of the Alaska State Library, located in the State Office Building in Juneau (open 1-5 p.m. Monday through Friday; 907-465-2927).
Posted: October 31, 2013