Abstract:

Yisu(Yilan-Sulan)fault zone is a branch in the north section of the famouse Tancheng-Lujiang fault zone in East China.In application of Maniar's granitoid discrimi-nation,Mesozoic granitoids distributed in Yilan-Sulan area could be classified into follow-ing types:1.continental-arc granitoids(CAG)of Triassic-middle Middle Jurassic;2.post-orogenic granitoids (POG) from late Late Jurassic to early Early Cretaceous;3.the CAG and POG granitoids of Late Jurassic.The tectonic environment of the granitoids and the plate tectonic settings of the whole Northeast China in Mesozoic were coordinated and could be divided into four evolution stages:1.intra-continental arc strike-slip faulting(T-J₃²);2.post-orogenic rudimento-graben (J₃³-K₁¹);3.passive rift (K₁²-K₂) and 4.rift contraction (K₃).