Geographic Orientation

This animation follows the edge of the Niagara Escarpment starting south of the Credit River and ending at Georgian Bay in the north. Generally, the escarpment is defined by the sharp colour break between orange and purple. The middle of the animation is in the vicinty of Caledon (1) and Mono Mills (2), atop the Niagara cuesta. At the end of the animation various valley reentrants are present in the Escarpment, from south to north these are; the Hockley Valley, the Sheldon Valley. The blue in the distance is Georgian Bay. To enhance the Niagara Escarpment a customized enhancement was employed; consequnetly, the colour legend as presented does not apply to this animation.

Landscape Description

The Niagara Escarpment is a bedrock feature extending from New York State in the south to the Bruce Peninsula in the north. Atop the Escarpment sub-horizontal Silurian dolostones crops out while Ordovician rocks crops out below and to the east of the Escarpment. Differential erosion of softer Ordovician shales and limestones is responsible for formation of the Escarpment. The escarpment is ornamented by a number of moraines, the Paris, Singhampton (3) and Gibraltar (4). The escarpment is cut by a number of paleofluvial valleys which have been accentuated by glacial meltwater erosion and re-occupied by modern rivers. The most notable of these are the Credit River valley, and the Hockley, Sheldon, Pine and Mad valleys. The escarpment is draped by glaciolacustrine sediments, and is practically buried south of Mono Mills by the onlapping Oak Ridges Moraine.

Further Information

Chapman, L.J. and Putnam, D.F. 1966: The Physiography of Southern Ontario, 2nd edition; University of Toronto Press, 386 p.

Russell, H.A.J., and Dumas, S. 1997: Surficial geology of the Alliston area, NTS 31 D/4 southern Ontario; Geological Survey of Canada, Open File 3334, scale 1:50 000.

Russell, H.A.J., and White, O.L. 1997: Surficial geology of the Bolton area, NTS 30 M/13, southern Ontario, NTS 30 M/13. Geological Survey of Canada, Open File 3299, scale 1:50 000.

Straw, A. 1968: Late Pleistocene glacial erosion along the Niagara Escarpment of Southern Ontario; Geological Society of America Bulletin, 79, 889-910.

Tinkler, R.J. and Stenson, R.E. 1992: Sculpted bedrock forms along the Niagara Escarpment, Niagara Peninsula, Ontario; Geographique physique et Quaternaire, 46, 195-207.

White, O.L. 1975: Quaternary Geology of the Bolton area, southern Ontario; Ontario Division of Mines Geological report 117, 119 p