Global Geochemical Fingerprinting Points to a Mantle Dynamics Coupled with the Supercontinent Cycle

Plate tectonics and mantle plumes are two of the most fundamental solid-Earth processes that operated through much of the Earth’s history. For the past 300 million years, mantle plumes are known to derive mostly from two large low shear velocity provinces (LLSVPs) above the core-mantle boundary, referred to as the African and Pacific superplumes. Whether such LLSVPs and their plume products are stationary through Earth history, or dynamically linked to global plates motions and subduction geometry, remains a first-order question for the geoscience community. Here, we demonstrate that transition elements (Ni, Cr and Fe/Mn) in basaltic rocks can be used as a tool to trace plume-related magmatism through Earth history. An analysis of the global petro-chemical database indicates the presence of a direct relationship between the intensity of plume magmatism and the supercontinent cycle. Such results favour the presence of a dynamic supercontinent-superplume coupling over the fixed-LLSVP geodynamic model. In addition, our analysis shows a consistent sudden drop in MgO, Ni and Cr at ~3.2–3.0 billion years ago, possibly indicating an abrupt change in mantle temperature at the start of global plate tectonics.