Meso‐Cenozoic rheological structure of the Linqing Depression: Implications for cratonic destruction

Abstract

The evolution of the lithospheric rheological structure can reveal geodynamic processes of cratonic destruction. Using data of palaeo‐heat flow, crustal structure, and rheological parameters, we studied the rheological structure of the Linqing Depression. The results show that the lithosphere of the Linqing Depression experienced two stages of weakening, one in the Cretaceous and the other in the Palaeogene, with lithospheric strengths of approximately 2.09 and 1.67 × 1012 N/m and effective elastic thicknesses (Te) of approximately 24 and 20 km, respectively. The Meso‐Cenozoic rheological structures correspond to the ‘jelly sandwich’, ‘crème brûlée’, and ‘banana split’ models. The transformation of these models is closely related to the thermal regime, stress environment, and mantle water content of the Linqing Depression. The rheological structure evolution of the Linqing Depression is correlated with the cratonic destruction of the North China Craton. The geodynamic mechanism of lithospheric weakening in the late Early Cretaceous is related to the subduction and retreat of the Pacific Plate, and the lithospheric weakening in the late Early Palaeogene was a combined effect of the Indo‐Asian collision and subductions of the Pacific and Philippine Sea plates.