At the Bear Creek occurrence, from 15 to 20 centimetres of impure diatomite is reported to extend for considerable distance along a creek and the "Bear River valley", under about 30 centimetres of peat. Isolated pure white patches occur under a bridge at the outlet of "Bear Lake". The diatomite in this region is of recent age and mainly unconsolidated. The diatomite is underlain by sedimentary rock of the Upper Cretaceous Nanaimo Group.