摘要
Three fragments of the Archean oceanic crust have been found between the Archean granulite belt and the Paleo-Proterozoic Hongqiyingzi group in North China craton, which spread along the Shangyi-Chicheng ancient fault. This paper presents integrated field, petrology, geochemistry and geochronology evidence of the ancient oceanic fragments. The magma crystallizing age of the tonalite in the Shangyi complex is 2512±19 Ma and the geochemical characteristics suggest that the Nbenriched basalts may be related to crustal contamination and formed in the intra-oceanic arc of the supra subduction zone setting.
Three fragments of the Archean oceanic crust have been found between the Archean granulite belt and the Paleo-Proterozoic Hongqiyingzi group in North China craton, which spread along the Shangyi-Chicheng ancient fault. This paper presents integrated field, petrology, geochemistry and geochronology evidence of the ancient oceanic fragments. The magma crystallizing age of the tonalite in the Shangyi complex is 2512±19 Ma and the geochemical characteristics suggest that the Nbenriched basalts may be related to crustal contamination and formed in the intra-oceanic arc of the supra subduction zone setting.
基金
supported by the State Key Laboratory ofGeological Processes and Mineral Resources,China(No.GPMR0741)
Research Fund for the Doctoral Program ofHigher Education of China(20070491516)
NSFC(No.40472096 and 90814006),which is dedicated to the 100anniversary of geological department,Peking university
