Portage Bay

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Gangue minerals pyrite

Geographic location

Quadrangle map, 1:250,000-scale UN
Quadrangle map, 1:63,360-scale B-3
Latitude 53.7333
Longitude -166.75
Nearby scientific data Find additional scientific data near this location
Location and accuracy Centered in valley northeast of Cannery Point in the Portage Bay - Makushin Bay area. Anomaly no. 12 of Christie (1974).

Geologic setting

Geologic description

Very large, 5,000 ft (1,500 m) by more than 5,000 ft (1,500 m) intense yellow-brown to red-brown color anomaly elongated parallel to valley, roughly northeast. Pyrite is disseminated through amygdaloidal andesite flows, minor pyroclastic rocks, and porphyritic andesite. No intrusive rocks were found within the color anomaly. Christie (1974) interpreted that the alteration is solfataric in nature. Fracturing is mainly post-mineralization.
Geologic map unit (-166.75187807208, 53.7324482330255)
Age of mineralization Cenozoic
Alteration of deposit Argillic alteration and local silicification reported. Minor leaching.

Production and reserves

Workings or exploration Reconnaissance mapping only, no sampling.
Indication of production None


MRDS Number A106016


Christie, J.S., 1974, Aleut-Quintana-Duval 1974 joint venture, final report: Unpublished Quintana Minerals Corporation report, 24 p., 3 appendices, 2 maps. (Report held by the Aleut Corporation, Anchorage, Alaska.)
Reporters Damon Bickerstaff, F.H. Wilson
Last report date 5/3/1994