Niagara Escarpment – One of the world’s unique natural wonders (FREE)
Niagara EscarpmentThe Niagara Escarpment begins in Watertown New York, USA and continues westerly along the Manitoulin Island in the Province of Ontario, Canada. It continues through Wisconsin and Illinios.
It is 1,609 kilometers in length and is the weathered edge of a very ancient sea bottom. Throughout its length from Hamilton, Ontario to Watertown, New York the escarpment ranges from 183 meters (600 feet) above sea level to 189 meters (620 feet) above sea level. The Niagara Escarpment is the ultimate reason the Falls of Niagara was born. Without the escarpment, Niagara Falls may never have materialized. After millions of years, the Niagara Escarpment continues to erode in a southward direction. The Niagara Escarpment was formed and existed before glaciations. The land that is now Southern Ontario emerged from the sea of the Paleozoic Era at least 245 million years ago or more. The Ordovician and the Silurian rocks of the Niagara Escarpment are of the oldest found in Niagara dating back to 430 – 415 million years ago. The escarpment is not a fault line or a rift line but was created through erosion. It is a “cuesta”. The height of the Niagara Escarpment at Lewiston, New York is 76 meters (250 feet). Five kilometers west of Lewiston, New York, the escarpment is so steep that it rises 73meters ( 240 feet) in 0.4 kilometers (1/4 mile). The eastern portion of the Niagara Escarpment is higher than in the west. The escarpment at Watertown, New York is 147 meters (483 feet) above sea level. The ancient uplift and rising crust of the land in the eastern portion of North America is quite noticeable. Only in Niagara can one find a gravel beach 147 meters (483 feet) above the nearest body of water. To understand the age of the Niagara Escarpment consider the following time line: | | EVENT | 430 – 415 million years ago | rocks of the Niagara Escarpment | 295 million years ago | Appalachian Mountains | 225 – 83 million years ago | Triassic, Jurassic Period (dinosaurs roam earth) | 83 – 60 million years | dinosaurs extinct | 1.5 million years ago | earliest man in Africa | 14 thousand years ago | continental glaciers in Northern Hemisphere at their maximum extension | 14 – 12 thousand years ago | Wisconsin Glacier cover – retreats | 12 thousand years ago | Niagara Falls begins | 12 – 11 thousand years ago | Lower Great Gorge | 10 – 6 thousand years ago | Whirlpool Rapids Gorge | 6 thousand years ago | modern Lake Erie | 5 thousand years ago | Upper Great Gorge |
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