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in Motoyoshi, Y. and Shiraishi, K. (editors), Origin and Evolution of Continents: Proceedings of the International Symposium "Origin and Evolution of Continents," 13-14 October, 1997, Tokyo, Memoirs of National Institute of Polar Research, Special Issue, No. 53, p. 214-229, 1999.

Abstract
Gondwana, with East Antarctica as its center, began to break up during Late Triassic to Early Jurassic time. Use of the satellite derived gravity map to approximate the ocean-continent boundary allows us to generate a much tighter fit for the reconstructed supercontinent then previously attempted. Major mantle plumes such as the Karoo-Ferrar Plume that first split Gondwana at about 182 Ma, the Paraná-Etendeka plume at 132 Ma that split South America and Africa, the Marion plume at 88 Ma that split Madagascar and India and finally the Reunion hotspot that split the Mascarene Plateau from India at 64 Ma, were all critical events in the break-up of Gondwana. Our tight-fit produces overlap between cratonic East Antarctica and the Limpopo Plain of Mozambique but there is no evidence that the crustal material underlying the Limpopo Plain pre-dates the break-up of Gondwana. Likewise Madagascar has been reconstructed so that it substantially overlies coastal East Africa in the vicinity of the Anza Trough, an early Jurassic rift in Kenya. The western margin of the island of Madagascar may in fact be crustal material that is younger than the break-up. It may have been produced as a result of the Karoo mantle plume or some may have been the result of the Marion hotspot. Between South America and Africa there are three significant overlaps. Two of them are deltaic, and the third is the Abrolhos and Royal Charlotte banks which post-date Gondwanide breakup by 80 to 100 million years.

Figures

Figure 1. Tight fit reconstruction of Gondwana at 200 Ma.

Figure 2. Satellite gravity data (Smith, W.H.F., and Sandwell, D.T., 1995, EOS, Fall Meeting Abstracts, 76(46): F156) showing the west coast of Southern Africa.

Figure 3. Detail of tight fit reconstruction shown in Figure 1.

Figure 4. Detail of continental regions at 160 Ma (Africa fixed in its present-day coordinates).

Figure 5. Detail of tight fit reconstruction shown in Fig. 1.