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 amalgamation based on detrital zircon ages from Neoproterozoic Ribeira and Dom Feliciano belts of South America and comparison with coeval sequences from SW Africa
复制标题
基于南美洲新元古代 Ribeira 和 Dom Feliciano 带碎屑锆石年龄的西冈瓦纳合并并与西南非洲同期序列的比较
DOI：
10.1144/sp294.13
复制
发表时间：
2008
影响因子：
1.8
通讯作者：
F. Preciozzi
中科院分区：
文献类型：
--
作者：
M. Basei;H. Frimmel;A. Nutman;F. Preciozzi
摘要西冈瓦纳古陆新元古代-寒武纪的融合作用是现今位于南美洲东部和非洲西部的几个古老地壳板块碰撞的结果。来自Ribeira和Dom Feliciano带（南美洲）和Gariep和达马拉带（非洲）的代表性变质沉积单元的U-Pb（SHRIMP）碎屑锆石年龄对可能的缝合带中可能的沉积物源区提供了限制。Ribeira碎屑锆石为古元古代和太古代。对于多姆费利西亚诺带，中新元古代锆石的贡献，这肯定表明新元古代沉积。据推测，流入里贝拉盆地的物质主要来自Paranapanema和Rio de拉普拉塔盆地，而达马拉和Gariep-Rocha带的源区则来自Namaqua带。Dom Feliciano带的沉积物来自南美洲一侧，并在较小程度上来自非洲。这些结果突出了在整个拟议的西冈瓦纳缝合线的碎屑锆石签名的差异，在西部来自独特的南美基底来源和那些在东部独特的非洲来源。
Abstract 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.