COMPARISON OF THE JURASSIC AND CRETACEOUS SEDIMENTARY CYCLES OF SOMALIA AND MADAGASCAR - IMPLICATIONS FOR THE GONDWANA BREAKUP

The Jurassic and Cretaceous sedimentary history of northern Somalia an d the Morondava Basin of south-western Madagascar have been studied. B oth regions display an independent facial development; however, a comp arison of the sequential evolution of the Mesozoic sedimentary success ions in these two presently widely separated areas reveals a surprisin gly high level of similarity, which probably reflects major events dur ing the disintegration of Eastern Gondwana during the Jurassic and Cre taceous. Although in Jurassic times the onset of transgressions and re gressions in both areas compares well with eustatic development, major deviations in combination with the tectonic activities of different d egrees are observed in the Early and Late Cretaceous synchronously in both regions. Transgressions are observed in Toarcian, Bajocian (not d ated in northern Somalia), Callovian, Valanginian (Madagascar only), A ptian and Campanian times. Tectonism is noted before the Aptian and Ca mpanian transgressions in northern Somalia and the Morondava Basin of south-western Madagascar.