EarlyCretaceous‐Cenozoicexhumation history of Luxi Terrane and adjacent areas, eastern North China Craton

Abstract

The Luxi Terrane is important for understanding the large‐scale extension and lithospheric thinning in eastern North China Craton (NCC) during the Mesozoic to Cenozoic. However, the exhumation/uplift history of the whole region in comparison to its adjacent areas is still unclear. To address this issue, we compiled 892 thermochronological data using jointly Kernel density estimation and linear inversion approaches to identify the exhumation episodes and estimate the temporal and spatial variation of the exhumation rates. The results indicated that these areas all experienced three rapid exhumation episodes, throughout the Early Cretaceous (120–100 Ma), Late Cretaceous‐Palaeocene (90–60 Ma), and Eocene (50–35 Ma). While the existence of synchronous tectonic evolution, the exhumation rates are heterogeneously distributed throughout the Luxi Terrane and neighbouring areas in space and time. We suggest that tectonics may play a role in setting up the regional variation in exhumation patterns. Considering the plate reconstructions and integrating low‐temperature thermochronological studies, the Early Cretaceous rapid exhumation corresponds to extensive craton destruction, linked with the Izanagi slab rollback within a back‐arc extensional setting. The Late Cretaceous‐Palaeocene rapid exhumation is interpreted as a response to continuing craton destruction and lithospheric thinning resulting from the subduction of Izanagi‐Pacific. In the Eocene, we propose that the coupling effect of subduction of Pacific Plate and India‐Eurasia collision can trigger this cooling episode.