Linking surface tectonics with mantle dynamics using numerical models with data assimilation

Quantifying surface manifestations of deep mantle dynamics represents an ultimate goal of Earth science. This task has remained challenging due to uncertain initial and boundary conditions of the 4D nature of Earth evolution. A promising solution is through data assimilation, which substantiates a large number of model parameters with available data, thus greatly reducing model uncertainties. During the past decade, our group has developed both forward-in-time and backward-in-time data assimilation techniques that have greatly improved the quantitative expressions on the linkage between deep mantle dynamics and surface tectonics. Here, I will demonstrate how these data-assimilation models work in practice, and how oceanic subduction and the resulting mantle flow influence the Earth surface through generating 3D lithospheric deformation, intraplate volcanism, and earthquakes. Specific examples include the circum-Pacific plates subduction below continents, and evolution of the cratonic lithosphere.