Earth Science Frontiers ›› 2023, Vol. 30 ›› Issue (4): 218-228.DOI: 10.13745/j.esf.sf.2023.4.30

• Special Section on The India-Eurasia Collision and Its Long-Range Effect (Part 8) • Previous Articles     Next Articles

Overview of the crustal and upper-mantle structures of the Mongolian Plateau

YANG Wencai1,2(), CHEN Zhaoxi2, SHI Zhanjie1   

  1. 1. School of Earth Sciences, Zhejiang University, Hangzhou 310058, China
    2. School of Geophysics and Information Technology, China University of Geosciences (Beijing), Beijing 100083, China
  • Received:2023-04-20 Revised:2023-05-10 Online:2023-07-25 Published:2023-07-07


Geophysical survey and comprehensive geological analysis show that the crustal structure of the Mongolian Plateau is mainly formed under the effects of terrane amalgamation and closures of the Paleo-Asian and Mongolia-Okhotsk Oceans. Among them, the closure of the Paleo-Asian Ocean affected mainly the west and south of the Mongolian Plateau, causing the crustal uplift in the Altai collisional orogenic belt and the subsidence of the Ubuds-Bayanhonggol crust, and affecting the secondary uplift of the Hangai Mountain massif. In the east of the Mongolian Plateau, there was no strong collision at the closing of the ancient Mongolia-Okhotski Ocean in the Mesozoic Era, and the upper and lower Amur massifs and the Xilinhot land block completely merged together into one land block. This type of terrane amalgamation indicated slow land-to-land subduction played a major role. Of course, slow land-land subduction might also cause numerous crustal deformation and magma intrusions leading to continental accretion. The closure of the Mongolian-Okhotsk Ocean did not result in obvious shortening and thickening of the Earth’s crust, but large-scale mantle source magma intrusions occurred, which caused the crust to melt and the crystalline bedrock to cratonize rapidly. In the upper mantle beneath Mongolia, there are residual traces of a plume reflecting the thermal fluid upwelling to the uppermost mantle.

Key words: continental dynamics, Mongolia Plateau, terrane amalgamation, crust structure, continental accretion

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