Structure & Location

The Niagara Escarpment is a geologist's paradise and contains some of the best exposures of rocks and fossils of the Palaeozoic Era found anywhere in the world.

As a landform, the Escarpment began to form only after the ancient sea withdrew some 300 million years ago.

Over succeeding millions of years erosive agents slowly removed the softer shales underlying the more resistant dolostone layers.

As the softer underlying material was eroded away , large blocks of the resistant dolostone caprock broke off creating the vertical face of the present day Escarpment.

Though of pre-glacial origin, the Escarpment face has been dramatically altered by successive advances of Pleistocene ice sheets over the last one to two million years.

The erosive power of the glaciers can be observed in several places, such as the widening and deepening of the Beaver Valley or the numerous rock fragments and boulders carried miles from the Escarpment and deposited in massive moraines.

This mass of material deposited by the ice and ensuing meltwater, covering the rock as much as several hundred feet in places, was even more important in modifying the appearance of the Escarpment. Glaciation, therefore, has made it very difficult for an observer to determine the exact location of the Escarpment in areas such as Mono Township and Caledon.

Weathering and erosive forces that initially carved the Niagara Escarpment are the same ones still occurring today. These include running water, waves, frost action, ice and wind.