Abstract: International audience ; The tectono-magmatic evolution of the North China Craton (NCC) plays a crucial role in understanding the Jurassic–Early Cretaceous (Yanshanian) intracontinental orogeny in East Asia. A holistic understanding of multi-phased deformation and magmatism in the NCC is greatly complicated by the sporadically distributed Mesozoic strata with significantly different stratigraphic associations in various zones. In this paper, we review the Jurassic–Early Cretaceous litho-stratigraphy with emphasis on unconformities to define a coherent chronostratigraphic framework of the entire NCC. Integrating available data concerning tectonic deformation, and geochemistry and fabric of igneous rocks into the well-established coherent chronostratigraphic framework, a four-stage tectonic evolutionary model of the NCC is proposed, providing new insights into the dynamics of the Yanshanian intracontinental orogeny in East Asia. The first stage concerns a N–S extension in the NCC during the Early–early Middle Jurassic (∼200–170 Ma), expressed by the E–W striking brittle normal faults developed in the Lower–lower Middle Jurassic strata, and magmatism along the southern and northern margins of the NCC. It could be related to the post-orogenic extension after the deep continental subduction of the South China Block beneath the NCC. The second one is characterized by a N–S compression (i.e., Event A of the Yanshanian orogeny) in the late Middle Jurassic (∼170–160 Ma), evidenced by the unconformity above the Lower–lower Middle Jurassic strata and the upper Middle Jurassic syn-tectonic deposition. The associated N–S directed thrusts and fault-related folds were mainly localized in the northern part of the NCC, possibly responding to the far-field compression related to the closure of the Mongol–Okhotsk Ocean. The third stage corresponds to a NW–SE compression (i.e., Event B of the Yanshanian orogeny) during the Late Jurassic–earliest Cretaceous (∼160–135 Ma), illustrated by the NW–SE directed thrusts and the overprint ...
Processing Request
No Comments.