Ankle Creek

Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities As; Cu; Hg; Pb; Zn
Ore minerals gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale PM
Quadrangle map, 1:63,360-scale A-2
Latitude 55.189
Longitude -160.655
Nearby scientific data Find additional scientific data near this location
Location and accuracy The map site of the Ankle Creek prospect is at an elevation of 600 feet, about 1,000 feet north-northwest of the center of sec. 3, T. 58 S., R. 75 W., Seward Meridian. The location is accurate to within 1,200 feet.

Geologic setting

Geologic description

The Ankle Creek quartz vein is parallel to the Surprise vein (PM089), and crops out approximately 200 feet to the southeast. It is as much as 50 feet in width and has been exposed for 130 feet on strike. Based on float, air photo lineaments, and ground magnetics, the Ankle Creek vein has been traced for approximately 1,200 feet to the northeast where it intersects the Amethyst vein (PM092) (Peterson and others, 1982, figure 11). The vein is hosted in andesite flows which belong to the late Eocene to early Oligocene Popof volcanic rocks (Wilson and others, 1995). The flows exhibit propylitic alteration near the vein. Pyrite apparently is widespread.
Two trenches have been cut across the vein at its southwest end. Float samples of vein material assayed as much as 0.30 ounce of gold and 0.60 ounce of silver per ton (Trujillo and others, 1981). The best trench sample assayed 0.014 ounce of gold and 0.03 ounce of silver per ton over 12 feet. This includes a 5-foot interval grading 0.048 ounce of gold and 0.03 ounce of silver per ton. Assays from the other trench were 0.003 ounce of gold and 0.02 ounce of silver per ton over 7 feet, and 0.005 ounce of gold and 0.04 ounce of silver per ton over 3 feet. The assays also show varying amounts of copper, lead, zinc, and mercury.
Three holes were drilled to intersect the vein at depth. Apparently only one hole (AQANK-2) was successful. Where intersected, the vein had narrowed to 8 feet and was almost entirely devoid of gold (Trujillo and others, 1981).
Geologic map unit (-160.657067494309, 55.1881636332872)
Mineral deposit model Epithermal gold vein
Age of mineralization Eocene or younger.
Alteration of deposit Andesite host rocks are propylitically altered.

Production and reserves

Workings or exploration During the period 1979 to 1981 Resource Associates of Alaska mapped and sampled the prospect, conducted a magnetic survey, cut two trenches, and drilled three core holes (Trujillo and others, 1981). Float samples assayed as much as 0.30 ounce of gold per ton, whereas the best in-place metal values were from a 12-foot-long trench sample that assayed 0.014 ounce of gold per ton.
Indication of production None

Additional comments

This prospect is located on land patented by, or interim-conveyed to, the Aleut Corporation.

References

MRDS Number 10308154

References

Andersen, G.D., Butherus, D.L., Fankhauser, R.E., Pray, J.C., Lindberg, P.A., and Hoffman, B.L., 1980, Exploration and evaluation of lands leased from Aleut Native Corporation 1980: Resource Associates of Alaska Report, 84 p, 16 map sheets, various scales. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Peterson, R.J., Lemmers, J., Handverger, P., Gallagher, J., Pilcher, R., East, J., Macleod, T., Bartels. E., 1982, Geology and precious metals potential Unga, Popof, and Korovin Islands, Shumagin Group, Aleutian Chain, Alaska: UNC Teton Exploration Drilling Company report, 127 p., 5 map sheets, various scales. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Trujillo, R.S., Andersen, G.D., MacLeod, T., Hendrick, K., Farnham, S., Peterson, J., 1981. Exploration and evaluation of the Unga-Popof-Korovan Islands portion of lands leased from Aleut Native Corporation: Resource Associates of Alaska report, 70 p., 38 map sheets, various scales. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Reporters S.H. Pilcher
Last report date 2/2/2001