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The Atlantic Ocean-bed


The Post Clam-shell Expansion centred mainly around the opening up of the Atlantic ocean-bed and its northern continuity, the Arctic Ocean-bed. Both of these tectonic developments dramatically affected North America’s continental position and shape.


The Arctic Ocean-bed pushed Alaska (which was nested above Russia’s north west coast) and North America along the entire length of the Asian continent in a strike/slip motion. Meanwhile the North Atlantic Ocean-bed began pushing North America in a north-west direction creating another strike/slip action in the Rocky Mountains area. In other words, Alaska and the west side of America moved at a different rate to central and eastern parts of North America.


North America’s northern crust suffered a great deal of stretching too and many basins developed and these formed the numerous great lakes.


































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