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| | Geological Society of America - GSA Today - v. 10, no. 2, February 2000 (Site not responding. Last check: 2007-10-08) |
 | | Overall, the Kaapvaal craton is made up of a number of granite-greenstone terranes with distinctive igneous rocks, deformation histories, and tectonic styles that were welded together to form the core of the continent (de Wit et al., 1992). |
 | | In contrast to the Late Archean ages of central craton granulite xenoliths, the abundant garnet-bearing granulite and upper amphibolite facies xenoliths from the Markt kimberlite, at the southwestern edge of the craton, yield Mesoproterozoic metamorphic zircon U-Pb dates ranging from 1114 to 1092 Ma (Schmitz and Bowring, 1999). |
 | | As is typical of Archean cratons, preliminary seismic results from the Kaapvaal project (James et al., 1999) show that the Kaapvaal and Zimbabwe cratons are underlain by a thick, seismically fast "root" that extends to depths of at least 200250 km. |
| www.geosociety.org /pubs/gsatoday/gsat0002.htm (4565 words) |
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