Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry.

ABSTRACT: The evolution of the planetary interior during plate tectonics is controlled by slow convection within the mantle. Global-scale geochemical differences across the upper mantle are known, but how they are preserved during convection has not been adequately explained. We demonstrate that the geographic patterns of chemical variations around the Earth's mantle endure as a direct result of whole-mantle convection within largely isolated cells defined by subducting plates. New 3D spherical numerical models embedded with the latest geological paleo-tectonic reconstructions and ground-truthed with new Hf-Nd isotope data, suggest that uppermost mantle at one location (e.g. under Indian Ocean) circulates down to the core-mantle boundary (CMB), but returns within ≥100 Myrs via large-scale convection

SUBMITTER: Barry TL 

PROVIDER: S-EPMC5431867 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature