Links between large volcanic eruptions, basal mantle structures, and mantle plumes

Abstract Mantle plumes rise from the deep Earth, creating large volcanic eruptions responsible for the emplacement of large volumes of magma at Earth’s surface over a few million years. Statistical relationships suggest that hot basal mantle structures generate mantle plumes and large volcanic eruptions through time. In previous studies, mantle plumes were the implicit process connecting surface volcanic eruptions to hot basal mantle structures. Here we investigate the spatiotemporal links between volcanic eruptions, hot basal mantle structures and explicitly modelled plume conduits from 300 million years ago. We consider three distinct volcanic eruption databases, four tomographic models and six global mantle flow models. We show that deep plumes generated above mobile basal mantle structures account for most of the record of large volcanic eruptions. Through Monte Carlo significance testing we find a statistical-dependence relationship between modelled plume conduits and an eruption database containing both plume head and plume tail products. We show that these eruptions, if reconstructed above the exterior of basal mantle structures, are related to the edges of fixed basal mantle structures in one tomographic model, and to the edges of mobile basal mantle structures 1% to 1.6% denser than the surrounding mantle in three mantle flow models.