|Quadrangle map, 1:250,000-scale||TL|
|Quadrangle map, 1:63,360-scale||A-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The prospect is located about 3.8 miles north-northeast of Portage Pass, and about 0.32 miles west-northwest of the center of section 2, T. 23 N., R. 20 W., of the Seward Meridian. This location is accurate to within 1/2 mile.|
Geologic descriptionThis site is a mineralized zone within Oxide, the northernmost prospect at Estelle (TY019), and is about 2.5 km north of the original Oxide Ridge showing (TL077). Oxide North lies within a plutonic complex intruding a Jurassic to Early Cretaceous flysch sequence. This zone is characterized by disseminated arsenopyrite and tourmaline returned anomalous values in talus fines sampling. Soil geochemical surveys in the valley have returned widespread arsenic anomalies with gold (Millrock Resource, Inc., 2014).
|Geologic map unit||(, )|
|Mineral deposit model||Porphyry Cu-Au? or intrusion-related gold? (Cox and Singer, 1986; model 20c)|
|Mineral deposit model number||20c?|
|Age of mineralization||Late Cretaceous of younger based on the age of the host rock.|
|Alteration of deposit||Not indicated.|
|Workings or exploration||
Gold mineralization was initially discovered in 2008 when multiple vein zones containing arsenopyrite, pyrite and chalcopyrite were noted along nearby Oxide Ridge, a north-south trending ridge located in the southern part of the prospect. Extensive geologic mapping helped define the target.In summer, 2012, Millrock Resources, Inc., executed a chip sampling of mineralized outcrops, in addition to an induced polarization geophysical survey to test for disseminated sulfides. Soil geochemical surveys in the valley have returned widespread arsenic anomalies with gold (Millrock Resource, Inc., 2014).
|Indication of production||None|
http://www.millrockresources com/news/millrock_samples_9.1_grams_per_tonne_gold_over_27.4_meters_at_estelle_/?phpMyAdmin=M5%252C2KfdT1QNf0rgfF8WupuwwKLe (as of April 3, 2014).
http://www.millrockresources.com/projects/estelle/ (as of April 3, 2014).
Millrock Resources Inc., 2014, Estelle Gold Project overview:
Millrock Resources Inc., 2014, Millrock Samples 9.1 Grams Per Tonne Gold Over 27.4 Meters At Estelle Project, Alaska:
Reed, B.L., and Elliott, R.L., 1970, Reconnaissance geologic map, analyses of bedrock and stream sediment samples, and an aeromagnetic map of parts of the southern Alaska Range: U.S. Geological Survey Open-file Report 70-271, 24 p., 4 sheets, scale 1:250,000.
Reed, B.L., and Nelson, S.W., 1980, Geologic map of the Talkeetna quadrangle: U.S. Geological Survey Miscellaneous Investigations Map I-1174, 1 sheet, scale 1:250,000.
Reed, B.L., Nelson, S.W., Curtin, G.C., and Singer, D.A., 1978, Mineral resources map of the Talkeetna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-870-D, 1 sheet, scale 1:250,000.
Wilson, F.H., Hults, C.P., Schmoll, H.R., Haeussler, P.J., Schmidt, J.M., Yehle, L.A., and Labay, K.A., comps., 2012, Geologic map of the Cook Inlet region, Alaska, including parts of the Talkeetna, Talkeetna Mountains, Tyonek, Anchorage, Lake Clark, Kenai, Seward, Iliamna, Seldovia, Mount Katmai, and Afognak 1:250,000-scale quadrangles: U.S. Geological Survey Scientific Investigations Map 3153, pamphlet 76 p., 2 sheets, scale 1:250,000. (Available at http://pubs.usgs.gov/sim/3153/).
|Reporters||V.C. Zinno (Alaska Earth Sciences)|
|Last report date||4/3/2014|