Escuminac Formation

The Escuminac Formation is a geologic formation in Quebec. It preserves fossils dating back to the Frasnian, in the Devonian period.

Description
Miguasha National Park is located within this formation along the estuary of the Restigouche River on the south coast of the Gaspé Peninsula. The fossil biota from the Park is thus referred to as the Miguasha biota. The main Miguasha exposures were named the 'René Bureau Cliffs' after the geologist and paleontologist. This formation is sufficiently rich that some material could be sacrificed for microanatomical and histological study through thin sectioning; this was done, among others, for the actinopterygian Cheirolepis, the actinistian Miguashaia and the tetrapodomorph Euthenopteron.

The formation's depositional environment has been variously considered as lacustrine, estuarine, coastal marine or marine, though evidence from the fossil assemblage, stratigraphic and sedimentological setting, and geochemistry of the sedimentary rocks and bones suggests an estuarine interpretation is most fitting.