EGU21-14023
https://doi.org/10.5194/egusphere-egu21-14023
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Lithosphere flexure estimation of an non-uniform flexural rigidity plate:A quantitative modeling approach

Mingju Xu1,2,3, Zhaocai Wu3, Fei Ji4, Aiguo Ruan1,3, and Chunfeng Li2,5
Mingju Xu et al.
  • 1School of Earth Sciences, Zhejiang University, Hangzhou 310007, China. (11738013@zju.edu.cn)
  • 2Department of Marine Sciences, Zhejiang University, Zhoushan 316021, China
  • 3Key Laboratory of Submarine Geosciences, Second Institute of Oceanography, MNR, Hangzhou 310012, China.
  • 4Key Laboratory of Crustal Dynamics, Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085, China.
  • 5Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China

Lithosphere motion is one of the fundamental processes in Earth tectonics. To understand the processes involving the nature of tectonic evolution and dynamics, it is critical to figure out the lithosphere flexure of tectonic plates. Over long-term (> 105 yr) geological timescales, the lithosphere can be modelled as flexing like a thin, elastic plate, using the partial differential equation for flexure of an orthotropic plate. The partial differential equation is used indirectly to form theoretical admittance and coherence curves, which are then compared against the observed admittance and coherence to invert a non-uniform flexural rigidity (or effective elastic thickness, Te) plate. The non-uniform flexural rigidity lithosphere flexure amplitude can be estimated after that.

In this presentation, we use the classic lithosphere model with applied surface load at ground and internal load at Moho, but assume that the compensation material is denser than the mantle material beneath Moho. The density contrast between compensation material and mantle material beneath Moho is set to be 200 kg/m3 referring to the density contrast of the uppermost and bottom lithosphere mantle. In such a lithosphere model, errors of lithosphere flexure estimation are mainly contributed by the errors of Te and Moho recovering. Synthetic modelling is then performed to analyze the incoming influence deriving from Te and Moho errors.

The synthetic modelling reflects 1) the lithosphere flexure estimation errors are not sensitive to the errors of Te recovering, even an error of about 10 km of Te only result in an error within 1km of lithosphere flexure, 2) the influence of Moho errors to lithosphere flexure errors will be magnified in regions where Te is low, as lithosphere flexure errors over 1km mainly occur in regions where Te is lower than 8km.

How to cite: Xu, M., Wu, Z., Ji, F., Ruan, A., and Li, C.: Lithosphere flexure estimation of an non-uniform flexural rigidity plate:A quantitative modeling approach, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14023, https://doi.org/10.5194/egusphere-egu21-14023, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.