Supercontinent cycles modulate mantle structure and plume activity: A mechanism to form long-term periodicity in detrital zircons and LIPs records

Detrital zircons and large igneous provinces (LIPs) serve as primary proxies for crust production and plume activity, corresponding to arc and intraplate magmatism, respectively. The U-Pb age distribution of global detrital zircons and the temporal distribution of continental LIPs both exhibit long-term periodicities linked to supercontinent cycles. However, the mechanism driving such periodicity remains elusive. Here, using a 3-D global mantle thermochemical convection model with imposed plate motion velocity boundary conditions, we investigate the effects of supercontinent cycles on mantle convection structure and plume activity over the past 2000 Ma via a deep-origin plume detection scheme. Crucially, our results demonstrate that, mediated by the evolution of Large Low-Shear-Velocity Provinces (LLSVPs), supercontinent cycles strongly modulate mantle convection, driving periodic variations in mantle structure and plume activity on a ∼400 Myr timescale. This deep-mantle periodicity provides a unified origin mechanism for surface geological records: the high power of degree-2 mantle convection related to circum-supercontinent subduction correlates directly with detrital zircon age peaks, whereas higher-degree mantle structures and plume heat flux synchronize with the temporal distribution of LIPs.