Lava samples and seismic signals show that Earth's lower mantle is not well-mixed, but how this heterogeneity relates to the mantle's long-term history remains unclear. We study this with computer simulations of secular movements of masses in the mantle, with various materials to represent recycled and ancient rocks with different properties. We find that deep strong piles of recycled rock can help large ancient blobs survive, linking current deep-Earth observations to Earth's earliest infancy.

This research introduces a semi-structured conformal hexahedral mesh for three-dimensional magnetotelluric modeling. This enhances accuracy, efficiency, and flexibility, especially with local mesh refinement. Numerical tests confirm good accuracy and better results than standard meshes, validated against benchmark models. The codes effectively handle topography and complex zones, utilizing fewer nodes and elements to enhance modeling accuracy.

We present SK[K]S splitting measurements from 18 new seismic stations in the Zagros foreland, primarily in Iraq, offering novel insights into mantle flow and lithospheric deformation related to both ongoing and past tectonic processes. Results show two distinct anisotropic patterns: NE-SW orientation in northern Iraq, aligning with large-scale mantle flow, and NW-SE orientation in the Mesopotamian Plain and Persian Gulf, likely reflecting lithospheric remnants of past rifting.