Paleomagnetism of the Amazonian Craton and its role in paleocontinents

In the last decade, the participation of the Amazonian Craton on Precambrian supercontinents has been clarified thanks to a wealth of new paleomagnetic data. Paleo to Mesoproterozoic paleomagnetic data favored that the Amazonian Craton joined the Columbia supercontinent at 1780 Ma ago, in a scenario that resembled the South AMerica and BAltica (SAMBA) configuration. Then, the mismatch of paleomagnetic poles within the Craton implied that either dextral transcurrent movements occurred between Guiana and Brazil-Central Shield after 1400 Ma or internal rotation movements of the Amazonia-West African block took place between 1780 and 1400 Ma. The presently available late-Mesoproterozoic paleomagnetic data are compatible with two different scenarios for the Amazonian Craton in the Rodinia supercontinent. The first one involves an oblique collision of the Amazonian Craton with Laurentia at 1200 Ma ago, starting at the present-day Texas location, followed by transcurrent movements, until the final collision of the Amazonian Craton with Baltica at ca. 1000 Ma. The second one requires drifting of the Amazonian Craton and Baltica away from the other components of Columbia after 1260 Ma, followed by clockwise rotation and collision of these blocks with Laurentia along Grenvillian Belt at 1000 Ma. Finally, although the time Amazonian Craton collided with the Central African block is yet very disputed, the few late Neoproterozoic/Cambrian paleomagnetic poles available for the Amazonian Craton, Laurentia and other West Gondwana blocks suggest that the Clymene Ocean separating these blocks has only closed at late Ediacaran to Cambrian times, after the Amazonian Craton rifted apart from Laurentia at ca. 570 Ma. RESUMO: Dados paleomagnéticos obtidos para o Cráton Amazônico nos últimos anos têm contribuído significativamente para elucidar a participação desta unidade cratônica na paleogeografia dos supercontinentes pré-cambrianos. Dados paleomagnéticos do Paleo-Mesoproterozoico favoreceram a inserção do Cráton Amazônico no supercontinente Columbia há 1780 Ma, em um cenário que se assemelhava à configuração "South AMerica and BAltica" (SAMBA). Estes mesmos dados também sugerem a ocorrência de movimentos transcorrentes dextrais entre os Escudos das Guianas e do Brasil-Central após 1400 Ma, ou que movimentos de rotação do bloco Amazônia-Oeste África ocorreram dentro do Columbia entre 1780 e 1400 Ma. Os dados paleomagnéticos atualmente disponíveis do final do Mesoproterozoico s