Early and Middle Proterozoic Crustal History, Borborema Province, Northeast Brazil

巴西东北部博博雷马省早元古代和中元古代地壳历史

• 批准号: 9117594
• 负责人: W. Randall Van Schmus
• 金额: $ 10万
• 依托单位: University of Kansas Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-01-01 至 1994-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9117594&HistoricalAwards=false
• 关键词: Early; Middle; Proterozoic; Crustal; History

The Borborema tectonic province in northern Brazil formed during the 600 Ma convergence of the West African, Amazonian and San Francisco-Congo cratons to form the ancient supercontinent of Gondwanaland. Because of the strong tectonic overprint at 600 Ma it has been difficult to identify pre-Gondwana tectonic boundaries within Borborema province. This study will provide U/Pb age determinations for key lithologic suites and magmatic events and, together with ongoing geologic mapping by Brazilian colleagues, will allow the tectonic boundaries to be delineated. The results will provide much improved understanding of the pre-600 Ma tectonic history and assembly of Gondwanaland, and will contribute to key concepts of continental growth during the Precambrian.//

巴西北部的Borborema构造省形成于600 Ma西非，亚马逊和旧金山-刚果克拉通汇聚形成古冈瓦纳大陆。由于600 Ma强烈的构造叠印，很难在borborrema省确定前冈瓦纳构造边界。这项研究将为关键岩性层和岩浆事件提供U/Pb年龄测定，并与巴西同事正在进行的地质测绘一起，将使构造边界得以划定。这些结果将大大提高对600 Ma以前冈瓦纳大陆构造历史和组合的认识，并将有助于前寒武纪大陆生长的关键概念。//