Ontario Island

Ontario Island was a glacial feature as lobes of the Laurentide Glaciation receded from southern Ontario.^[1]^[2] The glaciation started to retreat approximately 20,000 years ago. As it retreated its southern edge was ringed by a series of proglacial lakes. The relatively high ground, west of the Niagara Escarpment formed a large island in these lakes.

References

^ Peter L. Storck (2011). Journey to the Ice Age: Discovering an Ancient World. UBC Press. ISBN 9780774841276. The first part of Ontario to become ice free was the high ground west of the Niagara Escarpment in south-central Ontario, a region geologists call Ontario Island.
^ "Elora and Fergus Geology". University of Waterloo. Retrieved 2023-09-07. The higher ground to the north of here, sometimes referred to as "Ontario Island," because it was surrounded by shrinking ice lobes and growing glacial lakes, tended to deglaciate first.

[JourneyIceAge-1] Peter L. Storck (2011). Journey to the Ice Age: Discovering an Ancient World. UBC Press. ISBN 9780774841276. The first part of Ontario to become ice free was the high ground west of the Niagara Escarpment in south-central Ontario, a region geologists call Ontario Island.

[WaterlooEloraFergus-2] "Elora and Fergus Geology". University of Waterloo. Retrieved 2023-09-07. The higher ground to the north of here, sometimes referred to as "Ontario Island," because it was surrounded by shrinking ice lobes and growing glacial lakes, tended to deglaciate first.

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