Seismic anisotropy

Abstract

Seismic anisotropy is ubiquitous throughout the Earth and provides constraints on dynamic processes, from the stress in the crust, the origin and evolution of the continental lithosphere, through convective flow in the upper mantle, to core evolution. The state of upper-mantle geodynamic modeling is such that important questions, such as about absolute plate motion reference frames, intraplate deformation, or the hydration state of the mantle can be addressed. Important issues about the resolution of different seismological datasets and degree of robustness of seismological images remain. Joint with the inherent uncertainties in geodynamic modeling and how to map flow into seismic anisotropy, this means that numerous questions for the interpretation of anisotropy observable are open. This challenge mandates further theoretical and instrumentational efforts and that the study of anisotropy proceeds interdisciplinary and in a dynamics context. Answering those questions holds the promise of arriving at a new understanding of the workings of the mantle system.