West Gondwana amalgamation based on detrital zircon ages from Neoproterozoic Ribeira and Dom Feliciano belts of South America and comparison with coeval sequences from SW Africa
M. A. S. Basei, H. E. Frimmel, A. P. Nutman, F. Preciozzi, 2008. "West Gondwana amalgamation based on detrital zircon ages from Neoproterozoic Ribeira and Dom Feliciano belts of South America and comparison with coeval sequences from SW Africa", 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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Neoproterozoic–Cambrian amalgamation of West Gondwana involved the collision of several terranes of older crust that are now in eastern South America and western Africa. U–Pb (SHRIMP) detrital zircon ages from representative metasedimentary units of the Ribeira and Dom Feliciano belts (South America) and Gariep and Damara belts (Africa) provide constraints on the possible sediment source areas across probable suture zones. Ribeira detrital zircons are Palaeoproterozoic and Archaean. For the Dom Feliciano Belt, a contribution of Meso- and Neoproterozoic zircons is present, which definitely indicate Neoproterozoic sedimentation. It is proposed that the inflow of material to the Ribeira basin was essentially derived from the Paranapanema and Rio de la Plata cratons, whereas for the Damara and Gariep–Rocha belts source areas were from the Namaqua Belt. The Dom Feliciano Belt received sediments from the South American side and to a lesser degree from African sources. These results highlight the differences in the detrital zircon signatures across a proposed West Gondwanan suture, with those in the west being derived from distinctive South American basement sources and those in the east from distinctive African sources.
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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.