Artículos de revistas
Radiating 1.0 Ga mafic dyke swarms of eastern Brazil and western Africa: Evidence of post-assembly extension in the rodinia supercontinent?
Registro en:
Gondwana Research. Elsevier Science Bv, v. 3, n. 3, n. 325, n. 332, 2000.
1342-937X
WOS:000088002900003
10.1016/S1342-937X(05)70291-4
Autor
Correa-Gomes, LC
Oliveira, EP
Institución
Resumen
Several mafic dyke swarms of similar composition and age (tholeiite- ca.1.0 Ga) occur on both sides of the Atlantic Ocean in eastern South America and western Africa. When assembled to their pre-drift position in the Mesozoic, the Brazilian coastal dyke province of Bahia, and the African dykes in Cameroun (Ebolowa suite) and Congo (Comba and Sembe-Ouesso provinces) define a giant radiating pattern (1200 km x 800 km) similar to other dyke swarms elsewhere associated with large-scale continental rifting. Magma flow indicators of the Brazilian dykes and branching propagation styles of their African counterparts indicate that the dyke conduits were fed with magmas diverging from a source beneath the long axis of the Meso-Neoproterozoic West-Congolian Basin in Africa. There, MORE-like metabasalts have been described in the La Bikossi Group of the Mayombian Supergroup. Whether the rifting event and intrusion of dyke swarms were triggered or not by a mantle plume beneath part of the Rodinia subcontinental lithosphere remain to be confirmed. 3 3 325 332