Destruction of the eastern North China Craton in a backarc setting: Evidence from crustal deformation kinematics

Abstract

The eastern North China Craton (NCC) west of the Pacific Ocean has a long history of rifting from Early Cretaceous to the end of Paleogene when the craton experienced destruction and significant thinning of the lithosphere. The cause and geotectonic environment for this destruction remain controversial. We use a set of field observation including basin patterns, fault geometry and kinematics, fault plane slip data, dike distribution, and fabric data from metamorphic core complexes to determine the kinematic evolution of the deformation in the eastern NCC during this period. We show that the principal extension direction in the eastern NCC evolved from WNW–ESE in the earliest-middle Early Cretaceous, via NW–SE in the latest Early Cretaceous, to nearly N–S in the Late Cretaceous–Paleogene. The movement history, from Late Mesozoic to Early Cenozoic, of the oceanic plates in the Pacific Ocean with respect to the eastern NCC is available from previous studies. The Izanagi Plate first subducted nearly orthogonally (WNW-wards) during earliest-middle Early Cretaceous time, and then moved obliquely (NNW-wards) in the latest Early Cretaceous while the relaying Pacific Plate moved generally northwards from the Late Cretaceous to Paleogene. Both the movement direction of oceanic plates and the principal extension direction of the continental deformation rotated clockwise. We suggest that such a correlation can be explained by the eastern NCC being in a backarc setting in the Cretaceous–Paleogene period. The results support the backarc extensional model for the destruction and significant lithospheric thinning of the eastern NCC.