The Empire Valley bentonite showing occurs within Eocene volcanic rocks to the west of the Fraser fault, correlative with the Kamloops Group volcanics east of the fault.

The showing is a five to ten metre wide, subvertical lens of bentonitic ash exposed in a roadcut at the northern end of the Empire Valley road. Movement along the Fraser fault, 300 metres to the east, has resulted in a complex geometry of high angle faulting exposed across the roadcut. The bentonite has been juxtaposed against Eocene conglomerate to the west and dark brown-weathering basalt to the east.