Abstract

AbstractSome changes in the topography of eastern China since Late Jurassic times cannot be well explained by lithospheric deformation. Here we analyze global mantle flow models to investigate how mantle‐driven long‐wavelength topography may have contributed to shaping the surface topography of eastern China. Paleodrainage directions suggest that a southward tilted topography once existed in eastern north China in the latest Jurassic Period, which is different from that at present day (southeastward tilting). Our model dynamic topography reveals a southward tilting topography between 160 and 150 Ma, followed by southeastward tilting and rapid subsidence, which is compatible with paleodrainage directions and tectonic subsidence of the Ordos Basin. The Cretaceous anomalous subsidence of the Songliao and North Yellow Sea basins, as well as the Cenozoic anomalous subsidence of the East China Sea Shelf Basin, can also be explained by dynamic topography. An apatite fission track study in the Taihang Mountains reveals four stages of evolution: Late Jurassic fast unroofing, Cretaceous slow unroofing, early Cenozoic fast unroofing, and late Cenozoic slow unroofing. We propose that mantle flow influenced this surface unroofing because the model predicts Late Jurassic dynamic uplift, Cretaceous dynamic subsidence, early Cenozoic dynamic uplift, and late Cenozoic dynamic subsidence. Apatite fission track data from northern south China are also in reasonable agreement with predicted dynamic topography between 80 and 30 Ma. The spatial and temporal agreement between geological observations and model dynamic topography indicates that mantle flow has had a significant influence in shaping the surface topography of eastern China.

Highlights

  • The topography of eastern China is laterally variable, consisting of plains mostly below 500-m altitude interspersed between mountains and foothills

  • Significant intraplate deformation has reshaped the topography of eastern China since the Late Jurassic Period, while analyses of paleodrainage, anomalous subsidence of major basins, and unroofing of mountains indicate large-scale topography change caused by mantle flow, induced by the time dependence of rapid convergence of the Pacific and Tethyan domains

  • The topography tilted southeastward due to the increasing influence of the Izanagi Plate, accompanied by the simultaneous subsidence of the Ordos Basin, Songliao Basin, and North Yellow Sea Basin between 160 and 90 Ma with small amplitudes, which is in reasonable agreement with model dynamic topography

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Summary

Introduction

The topography of eastern China is laterally variable, consisting of plains mostly below 500-m altitude (e.g., the Northeast Plain, the North China Plain, and the Middle-Lower Yangtze Plain) interspersed between mountains and foothills. Buried rift basins underlie most of these plains, reflecting past continental extension and diffuse deformation. The tectonic evolution of eastern China is complex. Subsequent to the final closure of the Paleo-Asian Ocean along the Solonker suture during late Permian times (Windley et al, 2007; Xiao et al, 2003), the Late Triassic amalgamation of the South China Craton (SCC) to the North China Craton (NCC) constitutes the final assembly of the major part of eastern China Significant intraplate deformation has reshaped the topography of eastern China since its assembly

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