Tracking mantle flow through seismic anisotropy and its link to geological observations

Understanding the internal dynamics, structure, and composition of our planet is a fundamental goal in Earth science. Geodynamic modelling has played a key role in this task, offering a theoretical window into the Earth’s convective mantle at present-day and in the past. Seismological studies provide robust evidence of mantle structure and dynamics. Furthermore, the detection of anisotropy of mantle minerals, such as olivine, which tend to align with the asthenosphere flow allows to map global anisotropy. This offers a seismic window into convective flow patterns beneath the lithosphere. In this endeavor, the asthenosphere plays a crucial role in connecting mantle dynamics to surface observations. Its channelized nature allows it to be modeled analytically within the framework of Couette and Poiseuille flow regimes. Thus, this methodology enables an efficient and comprehensive evaluation of a range of plausible models by systematically comparing them against global azimuthal anisotropy models. 

Here, I will introduce a fundamental analytical flow model designed to identify datasets that are sentive to the mantle flow, such as seismic anisotropy. The model predicts present-day asthenosphere flow and its azimuthal anisotropy, offering a clear expectation to where the model aligns well with seismic observations and where discrepancies occur.