Gun River Formation

The Gun River Formation is a geologic formation in Quebec. It preserves fossils dating back to the early Silurian period.

Description
The formation is divided into 4 members (from the base up): the Lachute, Innommée, Sandtop and Macgilvray members. The formation was deposited some 40–80 km offshore from the stable Laurentian craton, underwater at depths of 30 to 60 meters.