Correlation of Neoproterozoic terranes between the Ribeira Belt, SE Brazil and its African counterpart: comparative tectonic evolution and open questions
M. Heilbron, C. M. Valeriano, C. C. G. Tassinari, J. Almeida, M. Tupinambá, O. Siga, Jr, R. Trouw, 2008. "Correlation of Neoproterozoic terranes between the Ribeira Belt, SE Brazil and its African counterpart: comparative tectonic evolution and open questions", West Gondwana: Pre-Cenozoic Correlations Across the South Atlantic Region, R. J. Pankhurst, R. A. J. Trouw, B. B. de Brito Neves, M. J. de Wit
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Four main classes of tectonic entities may be considered for the Ribeira Belt and southwest African counterparts: (1) cratonic fragments older than 1.8 Ga and their passive margin successions, (2) reworked basement terranes with Mesoproterozoic and/or Neoproterozoic deformed cover, (3) magmatic arc associations, (4) terranes with Palaeoproterozoic basement and deformed Neoproterozoic back-arc successions. Based on comparative investigation, a tectonic model of polyphase amalgamation is proposed with c. 790 and 630–610 Ma major episodes of intra-oceanic and cordilleran arc magmatism along both sides of the Adamastor Ocean. Subsequent diachronous collision of the arc terranes and small plates followed at c. 630, 600, 580 and 530 Ma. The tectonic complexity reflects an accretionary evolution from Cryogenian to Cambrian times. The São Francisco–Congo and Angola palaeo-continents did probably not behave as one consolidated block, but rather may have accommodated considerable convergence during the Brasiliano/Pan-African episodes. The final docking of Cabo Frio and Kalahari in the Cambrian was coeval with the arrival of Amazonia on the opposite side, resulting in lateral reactivation and displacement between the previously amalgamated pieces. The transition between the Cambrian and the Ordovician is marked by the extensional collapse of the metamorphic core zones of the orogens.
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West Gondwana: Pre-Cenozoic Correlations Across the South Atlantic Region
Some 75 years after the visionary work of Wegener and du Toit, Neoproterozoic to Mesozoic geological correlations between South America and Africa are re-examined in the light of plate tectonics and modern geological investigation (structural and metamorphic studies, stratigraphic logging, geochemistry, geochronology and palaeomagnetism). The book presents both reviews and new research relating to the shared Gondwana origins of countries facing each other across the South Atlantic Ocean, especially Brazil, Argentina, Cameroon, Nigeria, Angola, Namibia and South Africa. This is the first comprehensive treatment to be readily available in book form. It covers the common elements of cratonic areas pre-dating Gondwana, and how they came together in late Precambrian and Cambrian times with the formation of the Pan-African/Brasiliano orogenic belts (Dom Feliciano, Brasília, Ribeira, Damara, Gariep, Kaoko, etc.). The subsequent shared Palaeozoic and Mesozoic sedimentary record (Karoo system) prior to Gondwana break-up is also reviewed.