GENERAL GEOLOGY

Detailed explanation-1: -The Niagara Escarpment is not formed by faulting. There is no displacement of the rock layers at the escarpment, as shown by study or rock exposures and drillholes. Additional resistant rock layers make more than one escarpment in some places.

Detailed explanation-2: -There were originally five spillways from Lake Erie to Lake Ontario. Eventually, these were reduced to one, the original Niagara Falls, at the escarpment at Queenston-Lewiston. From here, the falls began its steady erosion through the bedrock.

Detailed explanation-3: -As blocks of dolomite are undercut, they fall off and are rapidly destroyed by the falling water, further facilitating the retreat of the falls and the maintenance of a vertical cataract. The water flowing over the falls is free of sediment, and its clearness contributes to the beauty of the cataract.

Detailed explanation-4: -Falls were formed when melting glaciers formed massive fresh-water lakes (the Great Lakes) one of which (Lake Erie) ran downhill toward another (Lake Ontario). The rushing waters carved out a river in their descent and at one point passed over a steep cliff like formation (the Niagara escarpment).