Ocean Drilling Program cores and helium isotopes put better constraints on the ocean circulation in the north Pacific.
Abyssal peridotites show through their isotopic composition a complex history. From differences we can infer the existence of ultra depleted mantle and an uneven contribution to ridge magmatism.
Subduction of continental crust around the Gondwana supercontinent may explain the mantle Dupal anomaly of the southern hemisphere.
New data on ancient zircons points to a transition from stagnant lid to subduction style tectonics at 3.6 Ga ago.