The Bathurst Mining Camp occupies a roughly circular area of approximately 70 kilometres diameter in the Miramichi Highlands of northern New Brunswick. The area boasts some 46 mineral deposits with defined tonnage and another hundred mineral occurrences, all hosted by Cambro-Ordovician rocks that were deposited in an ensialic back-arc basin.

The volcanogenic massive sulphide deposits in the Bathurst Mining Camp formed in a sediment- covered back-arc continental rift during periods when the basin was stratified with a lower anoxic water-column. The basin was subsequently intensely deformed and metamorphosed during multiple collisional events related to east-dipping subduction of the basin. The rocks in the Bathurst Mining Camp are divided into five groups: the Miramichi, Tetagouche, California Lake, Sheephouse Brook, and Fournier groups, which are largely in tectonic contact with one another. The lower part of each group is dominated by felsic volcanic rocks and the upper part by mafic volcanic rocks, which are overlain by carbonaceous shale and pelagic chert. The basalts are both tholeiitic and alkalic and show a progression from enriched, fractionated continental tholeiites to alkali basalts to more primitive, mantle-derived midocean ridge, tholeiitic pillow basalts. Most massive sulfide deposits of the Bathurst Mining Camp are associated with felsic volcanic rocks in each group.

The Caribou deposit is a volcanogenic massive sulfide (VMS) deposit, is located in the northern part of the Bathurst Mining Camp and occurs in the core of a synformal structure that plunges steeply (80°-85°) to the north. The Caribou deposit is a VMS typical of the Bathurst Mining Camp, but is sufficiently distinct from the Brunswick type to warrant a subtype designation (Caribou type), within the Bathurst Mining Camp. Unlike the Brunswick-12 deposit, which is hosted by the Tetagouche Group, the Caribou deposit occurs in the California Lake Group near the base of a felsic volcanic rock sequence that comprises part of the Spruce Lake Formation. The Spruce Lake Formation volcanic rocks are petrologically and geochemically distinct from those of the Tetagouche Group. Furthermore, the Caribou deposit is not associated with the Algoma-type carbonate-oxide-silicate iron formation that overlies and is lateral to the Brunswick-12 and Heath Steele deposits.

The Caribou deposit consists of the following units from the base upward: (1) dark gray to black carbonaceous shale, pale gray phyllite, graywacke, and chloritic schist interbedded with hydrothermally altered pale green felsic volcanic rocks (footwall of the deposit); (2) stringer sulfides cutting hydrothermally altered sedimentary and felsic volcanic rocks; (3) massive sulfides comprising a vent complex and bedded sulfides; (4) chloritic schist at the contact between massive sulfides and overlying felsic volcanic rocks; and (5) interbedded felsic volcanic and sedimentary rocks.

Mineralization within the Caribou deposit is composed of seven en échelon lenses striking parallel to the Caribou fold numbered 10 to 80 that are zoned mineralogically and chemically from a copper-rich vent-proximal facies (vent complex) near the bottom and western part of each lens, to a lead-zinc-rich vent-distal facies (bedded sulphides) near the top and eastern part of each lens. The zones typically consist of 90% sulphides, mainly pyrite, sphalerite, galena and chalcopyrite. The main gangue minerals are magnetite, siderite, stilpnomelane, quartz and chlorite. Lenses 10, 20, 30, 70, and 80 occur on the north limb of the Caribou fold while lenses 40 and 60 are mostly on the eastern limb of the fold.