| Mobile belts of various ages seem to have stitched Africa's Archean cratons together by Himalayan-style continental collisions. |
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| Diamond is obtained from volcanic pipes composed of kimberlite or lamproite, rocks that are found only in cratons, very old stable areas of the Earth's crust. |
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| Although continents were small, they consisted of stable cratons. |
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| Kober could not know that today, 90 years later, cratons would be objects of intense study. |
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| Both arches intersect Archean Cratons, the Buffalo Head and the Hearne Province cratons. |
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| This accounts for the great age of the rocks comprising the continental cratons. |
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| The cratons are, from south to north, the Kalahari craton, Congo craton, Tanzania craton and West African craton. |
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| The cratons are connected by orogenic belts, regions of highly deformed rock where the tectonic plates have engaged. |
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| Although cratons are not tectonically active, they can be located near active margins, such as the Brazilian craton at the rear of the Andean active margin. |
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| Because of its similarity to the Canadian Shield and cratons of southern Africa and Western Australia, the Baltic Shield had long been a suspected source of diamonds and gold. |
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| Most known diamond deposits are located on cratons and the world's largest, the Superior Craton, covers most of northern Ontario, including the James Bay Lowlands. |
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| The complex defines a series of cratonic fragments related to the collision of the Amazonian and Sao Francisco Cratons. |
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