North america basement rocks 2005

North america basement rocks 2005. As radiometric ages were determined for the shield-like rocks on the continents which were either exposed at the surface, underlay the flat rocks, or were within the interior of the mountain belts, patterns of age intervals were determined. These old rocks have been called the "basement". This has been interpreted to mean that the continents had somehow grown by development of rock assemblages with these characteristic age parameters. The expanding continental nuclei are part of the "craton" which consist of both exposed and buried basement rocks.
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North america basement rocks 2005 - Related Maps

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Soil characterization of North America	The North America Tapestry of Time and Terrain	Structural Geology of North America
Volcanic rocks of North America	Sedimentary rocks of North America	Metamorphic rocks of North America
Plutonic rocks of North America	World geologic provinces	World soil regions
North American craton	North America physical map	North America physical map