Weak Cubic CaSiO₃ Perovskite in Earth’s Mantle

Research published in the journal Nature by Hauke Marquardt and others may change our understanding of subducting slabs in the deep mantle and calls for follow up studies on the relevance of the discoveries for the understanding of global geochemical cycles.

The subduction of tectonic plates is a key process governing plate tectonic movement. One of the key minerals in subducted oceanic crust reaching the deep mantle is cubic CaSiO3 perovskite, a mineral that has only recently been given the name davemaoite. Research led by the University of Oxford has now succeeded to experimentally quantify the plastic strength of davemaoite at the extreme pressure- and temperature-conditions expected at depths of up to about 1400 km.

“We found that cubic CaSiO3 perovskite, or davemaoite, is surprisingly weak in the deep mantle”, said Hauke, who led the research, “This finding might completely change our understanding of the dynamic behaviour of subducting slabs in the deep mantle”.

The research, calls for follow-up studies designed to quantify a range of possible geodynamic effects of weak davemaoite on the behaviour of subducting slabs in the mantle and their relevance to understanding global geochemical cycles.