EGU2020-2181
https://doi.org/10.5194/egusphere-egu2020-2181
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

The Tibet lithosphere is not all hot

Bing Xia1,2, Irina Artemieva3, and Hans Thybo4
Bing Xia et al.
  • 1State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
  • 2University of Copenhagen, Geology Section, Copenhagen, Denmark
  • 3Department of Geophysics, Stanford University, Stanford, California, USA
  • 4Eurasia Institute of Earth Sciences, Istanbul Technical University, Istanbul, Turkey

We calculated the thermal lithosphere structure of Tibet and adjacent regions based on the new thermal isostasy method. Moho depth is constrained by the published receiver function results. The calculated surface heat flow in the surrounded Tarim, North China, and Yangtze cratons have a good match with the real measurements of surface heat flow. We recognize the northern Tibet anomaly where has a relatively thin lithosphere with a thermal thickness of <80 km and surface heat flow of >80 - 100 mW/m 2 may cause by the removal of lithospheric mantle and upwelling of asthenosphere. In Lhasa Block, the cold and thick lithosphere (>200 km) with a surface heat flow of 40 - 50 mW/m 2. In the east Tibet, the heterogeneous thermal lithosphere does not follow the widely spread large scale strike-slip faults and suggested that the faults do not cut down to the lithosphere. The surrounding cratons have different thermal lithosphere features. The Tarim and Yangtze cratons show typical cold and thick lithosphere with a lithosphere of >200km and surface heat flow of <50 mW/m2. The western North China Craton has an intermated lithosphere with a thickness of 120-200km and surface heat flow of 45-60 mW/m2. Our result suggested that high and flat Tibet has different isostatic compensation in different blocks. The heterogeneous lithosphere thermal structure of the Tibet suggested that the uplife force drive are difference in Tibet.

 

How to cite: Xia, B., Artemieva, I., and Thybo, H.: The Tibet lithosphere is not all hot, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2181, https://doi.org/10.5194/egusphere-egu2020-2181, 2020