Dr. Daniel Peters, a former Postdoc from Hanika Rizo's lab, published a groundbreaking paper entitled, "Tungsten in the Mantle Constrained by Lithospheric Peridotites: Less Incompatible and More Abundant" in Geochimica et Cosmochemica Acta. The study's novel contribution is using mantle peridotites to determine the abundance of tungsten in the upper mantle.
The data obtained from this research indicates a higher abundance of tungsten in the bulk silicate Earth (BSE) than previous estimates, which relied on the tungsten concentration of mantle-derived lavas. The increased abundance of tungsten in the BSE leads to lover Hf/W ratio, which has implications for the timing of Earth's metal core formation. Specifically, the lower Hf/W ratio suggests that core formation occurred between 23-28 million years after the formation of the solar system, which is faster than previously estimated.
The study's findings also offer insights into the oxidation conditions during core-mantle equilibration and the pressure and temperature conditions during metal-silicate segregation. Additionally, the higher abundance of tungsten in the BSE may be attributed to a low carbon content of the Earth.
A copy of the Abstract can be viewed Here
Posted on: Thursday, May 11, 2023