A tungsten-rich porphyry molybdenum occurrence at Bear Mountain, Northeast Alaska

1987 annual report on Alaska's mineral resources

“…Tungsten-molybdenum porphyry mineralization at Bear Mountain in the ANWR was found to contain byproduct levels of columbium (Barker and Swainbank, 1986 On February 18, 1986, a coalition of environmental and Native groups filed a lawsuit against the BLM over various National Environmental Policy Act (NEPA) issues. The group asked that all mining on BLM lands be halted until the BLM conducted an environmental assessment of each mining operation.…”

Geologic map of Alaska

“…Mull, written commun., 2011). In Yukon, the plutons have been considered Devonian (Gordey and Makepeace, 2003); in the Table Mountain quadrangle, a rhyolite dike was dated at 56.4 Ma (Barker and Swainbank, 1986); whether this date reflects the age of any of the larger granitic plutons is uncertain. Devonian to Mississippian orthogneiss is also known farther west in the Brooks Range, in the Yukon-Tanana Upland and northern Alaska Range, and in the Tanana and Melozitna quadrangles of central Alaska (see units MDag, Dmi, and Dogn).…”