Tectonic control on topographic evolution of the East Asian coastal mountains

Our results show that the analyzed samples have varying emplacement depths and underwent different post-magmatic cooling histories, whereas thermochronological ages invariably reveal cooling and exhumation during the Late Cretaceous–Early Paleogene (ca. 90–40 Ma). We observe a systematic spatiotemporal pattern of progressively younger and more pronounced exhumation toward the Pacific coast and a major age break across the Zhenghe-Dapu Fault Zone.

We propose that these data record tectonic and erosional exhumation during the collapse of the mid-Cretaceous East Asia Coastal Mountains, triggered by tectonic extension during rollback of the retreating Paleo-Pacific slab. Our findings provide insights into the topographic evolution of other high-elevation subduction-related orogenic belts. Besides, we emphasize the importance of horizontal transect sampling in reconstructing the effects of different strain regimes and fault system evolution in low-relief subduction-related orogenic belts.