Abstract:

Neoproterozoic Baoxing Complex in middle to lower metamorphic grade, located in western margin of  Yangtze Craton, consists mainly of metamorphic gabbroic, dioritic gneisses, tonalitic and granodioritic gneisses, and massive monzogranites The studies of petrochemistry and SmNd isotopes of  Baoxing Complex reveal that the gabbroic and dioritic magmas came from a congenetic magma derived from the partial melting of spinel lherzolites in depletive mantle, and that the magma was intensively contaminated by crustal materials during its emplacement The tonalitic and granodioritic magma were derived from the partial melting of metamorphic basalts in the lower crust And the monzogranitic magma was formed from partial melting of metagreywacks Integrating the lithological association, their trace elements, SmNd isotopic characteristics and petrogenesis, the Baoxing Complex must likely have been emplaced in an island arc tectonic background at the Neoproterozoic active continental margin of Yangtze Craton

Key words: Baoxing Complex; geochemistry; SmNd isotopes；petrogenesis; tectonic background