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Should we care about supercontinent thermal insulation as a mechanism for mantle reversals?

In this short talk I will present an introduction to modeling supercontinent formation and dispersal in Cartesian boxes. In particular, I will be looking at the mantle mechanisms involved in the evolution of Pangea:  a landmass covering around 30% of the Earth's surface ~300-180 million years ago. Continents are believed to have aggregated into Pangea over a superdownwelling (large subduction zone) near the present day position of Africa. However, the present day mantle is characterized by anomalously warm mantle material beneath the Pacific and African plates. So what could cause a mantle reversal (e.g. cold, subducting oceanic plates replaced by warm mantle plumes) at the former site of supercontinent Pangea? One hypothesis is that because continental plates inhibit heat loss from the Earth's interior (due to their thick lithosphere and the warmth of their radioactively enriched crust), sustained thermal insulation on Pangean timescales (~150Myr) would be enough to generate elevated mantle temperatures. This study looks at how important an insulating supercontinent is in causing mantle reversals.