There is no direct geological information on the Marmot occurrence except for a brief 1899 report stating that the property had fine surface showings which had been stripped in various places with good results.

The occurrence is adjacent to the Mountain Treasure deposit (092F 175) which shows skarn mineralization for several hundred metres along a limestone-andesite contact. It is assumed that the Marmot occurrence is an extension of the Mountain Treasure deposit. If so, the deposit would consist of massive and/or disseminated pyrrhotite, pyrite, magnetite and chalcopyrite. The area is underlain by Lower Jurassic Bonanza Group volcanics. The limestone involved in the skarn event may be from the Quatsino Formation or from limestone beds found in the upper part of the Karmutsen Formation, both of the Upper Triassic Vancouver Group. Refer to the Mountain Treasure deposit for further descriptive and bibliographic details.