Mesozoic–Cenozoic evolution and mechanism of tectonic geomorphology in the central North China Block: Constraint from apatite fission track thermochronology

Abstract

During the Mesozoic–Cenozoic, the central North China Block underwent complex tectonic transition and significant changes of tectonic geomorphology. This apatite fission track study shows that the west part of the Taihang Mountains experienced a rapid event which commenced before 160Ma and lasted until 135Ma, together with the extensive development of folds and thrusts, indicating this area experienced intense compression and uplift. Combined with the petrological and geological characteristics, the exhumation event represents the uplift of the Yanshanian North China Plateau and the Taihang Mountains inside it. During the Cenozoic, two episodes of rapid cooling events took place during 65–55Ma and after 25Ma, respectively. The former one corresponds with the formation of the Bohai Bay Basin (BBB), which led to the extensional denudation of the Taihang Mountains. The formation of the Bohai Bay Basin disrupted the Yanshanian North China Plateau, caused the negative inversion of the tectonic geomorphology in the central North China Block. The thermal models indicates that the formation of north and south parts of the BBB commenced simultaneously in the south and north parts of the Taihang Mountains, implying the dynamics should be derived from the west or the east, rather than the north or the south. The latter cooling event took place earlier in the north part of the Taihang Mountains than the south part, corresponding with the Miocene thermal subsidence of the BBB.