Rivers in Rock: Elora Gorge Field Companion and Natural History (Hewitt Kenneth)(Paperback) - diskuze

This richly illustrated book is both a visitor's guide to one of southwestern Ontario's most striking landforms - the Elora Gorge on the Upper Grand River - and a thorough, accessible introduction to its natural and recent human history. The book introduces rivers that flow in bedrock, between rock walls and through precipitous gorges, unlike the subdued terrain that the last Ice Age bequeathed most of southwestern Ontario. It then leads the visitor to three viewpoints on and three excursions through the gorge, with a wealth of information about its rocks, fossils, caves, cliffs, rockslides, rockfalls, floods and erosional processes. It takes the reader through five "ages" of the gorge. In the First Age the gorge bedrock originated as reef limestone 430 million years ago in prehistoric tropical seas. The Second Age saw the gorge rocks make a great,
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