Natural Wonders | Geology

An Open Window on Ancient Environments

Forillon National Park is a prime site for exploring rock formations which form a sort of geological calendar. Here we find an exceptional phenomenon: ten separate and clearly visible geological formations juxtaposed in a narrow strip.

The story of their creation extends over the three periods in which the marine sediments that compose them were accumulated: the Ordovician (over 500 million years ago), Silurian (450 to 500 million years ago) and Devonian (345 to 450 million years ago). The rocky structures that are exposed in the park have a long geological history and bear eloquent witness to the movements of the earth's crust that gave birth to the Appalachian mountains.

The fossils found in the limestone and sandstone strata are further astonishing features that help to determine the relative ages of rocks, the sequence of the appearance of life forms on earth and the climatic conditions that prevailed when these life forms existed.

The park is located in a sea cliff region. Thus, it is not surprising that it has relatively rugged surface features, in keeping with the underlying geological structure. In the southern half of the park, the topography is directly influenced by the rock strata which tectonic forces have tilted to an angle of 20 to 30 degrees. The result is a series of ranges gently inclined toward the sea to the south and abruptly terminating at the centre of the park in rocky cliffs running parallel to the coastline. In the northern half more rolling relief, generally under 300 m in height, can be found. The landscape is broken up by many narrow, entrenched valleys, all running toward the Gulf of St. Lawrence.

The sea has moulded the coastline to produce a wide variety of forms, sculpting wave-cut terraces, high cliffs, coves and grottoes.