Physical & Chemical Weathering

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.

Running water and waves have created the most dramatic results. The effect of the wave action is well illustrated along the shores of Georgian Bay in the Bruce Peninsula, while the erosive force of running water is best displayed in the Niagara Gorge, which has been carved by the Niagara River over approximately the last 13,000 years following glaciation.

Erosion at the headwaters of the numerous streams rising on the Escarpment is largely responsible for the many indentations and irregular appearance of the Escarpment face. Outliers, or segments of the Escarpment separated from the main face such as at Milton or Glen Williams, are also the result of stream erosion.

Less obvious, but important, is the chemical weathering process whereby the porous dolostones are dissolved, creating karst features such as sinkholes and caves and leading to numerous springs along the base of the Escarpment (as seen in title photo). Good examples of sinkholes can be found on the west side of the Beaver Valley near Wodehouse and at St. Edmunds Cave at the top of the Bruce Peninsula.

Also, frost action is continually loosening large blocks of rock from the face creating a talus slope below. Sometimes a huge chunk of the Escarpment breaks off; this is called "mass wasting."

The Niagara Escarpment thus continues to slowly change by the same process that led its creation.