地质学报2025，Vol.99Issue(4)：1209-1222,14.DOI:10.19762/j.cnki.dizhixuebao.2023512
安哥拉地盾Quibala斑状花岗岩的年代学、地球化学特征:对Columbia超大陆演化的制约
Geochronology and geochemistry of Quibala porphyritic granites in the Angolan shield:Implications for the evolution of the Columbia supercontinent
摘要
Abstract
Global Columbia supercontinent assemblage occurred between 2.1 Ga and 1.8 Ga.The collision between the Congo and São Francisco cratons formed the Eburnean orogenic belt.As an important part of the Congo craton,the Angolan shield has recorded tectono-magmatic events during this period.This study investigates the petrology,zircon U-Pb chronology,and geochemistry of porphyritic granites in the Quibala area of the Angolan shield.LA-ICP-MS zircon U-Pb dating yielded ages of 1987±20 Ma,1967±6 Ma,and 1956±12 Ma,indicating that the porphyritic granite crystallized between 1987 Ma and 1956 Ma,coinciding with Paleoproterozoic Eburnean magmatism.Geochemical data classifies the Quibala porphyritic granite as A-type granite,suggesting formation in a post-collision extension setting.This granite may be formed by partial melting of lower crustal material influenced by crust-mantle interaction.Combining chronological and geochemical data,we propose that the Congo and São Francisco cratons,integral parts of the Columbia supercontinent,transitioned from a collisional to a post-collision extensional stage between 1987 Ma and 1956 Ma.关键词
安哥拉地盾/Congo克拉通/Quibala斑状花岗岩/A型花岗岩/Columbia超大陆Key words
Angolan shield/Congo craton/Quibala porphyritic granite/A-type granite/Columbia supercontinent引用本文复制引用
靳立杰,张洪瑞,罗迪柯,贾鹏飞,刘伟,王子圣,李金镇,周永刚,江振国..安哥拉地盾Quibala斑状花岗岩的年代学、地球化学特征:对Columbia超大陆演化的制约[J].地质学报,2025,99(4):1209-1222,14.基金项目
本文为安哥拉国家地质调查计划项目(PLANAGEO)资助的成果. （PLANAGEO）
