Argon argon dating range
The "Bullard fit" gives one of the best reconstructions of how Africa, South America, Europe, and North America may have once touched.
There are, however, areas of overlap of continents and one large area which must be omitted from consideration (Central America).
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In conformity with evolutionary-uniformitarian assumption, popular plate tectonic theory supposes that plates move very slowly — about 2 to 18 centimeters per year.A "zebra stripe" pattern of linear magnetic anomalies parallel to the ocean ridge crest has been noted in some areas and potassium-argon dating has been alleged to show older rocks farther from the ridge crest.There are some major problems with this classic and "most persuasive" evidence of sea-floor spreading.Especially interesting is how the eastern "bulge" of South America can fit into the southwestern "concavity" of Africa.Recent investigators have used computers to fit the continents.