Turbulent lithosphere deformation in the Tibetan Plateau

Abstract

In this work, we show that the Tibetan Plateau deformation demonstrates a turbulence-like statistics, e.g., spatial invariance cross continuous scales. A dual-power-law behavior is evident to show the existence of two possible conversation laws for the enstrophy-like cascade on the range $500\lesssim r\lesssim 2,000\,\si{km}$ and kinetic-energy-like cascade on the range $50\lesssim r\lesssim 500\,\si{km}$. The measured second-order structure-function scaling exponents $\zeta(2)$ are similar with the counterpart of the Fourier scaling exponents observed in the atmosphere, where in the latter case the earth rotation is relevant. The turbulent statistics observed here for nearly zero Reynolds number flow is favor to be interpreted by the geostrophic turbulence theory. Moreover, the intermittency correction is recognized with an intensity to be close to the one of the hydrodynamic turbulence of high Reynolds number turbulent flows, implying a universal scaling feature of very different turbulent flows. Our results not only shed new light on the debate regarding the mechanism of the Tibetan Plateau deformation, but also lead to new challenge for the geodynamic modelling using Newton or non-Newtonian model that the observed turbulence-like features have to be taken into account.