Viscosity measurements offer new insights into the earth's mantle
An international research group with Dr. Longjian Xie from the Bavarian Research Institute of Experimental Geochemistry & Geophysics (BGI) of the University of Bayreuth has succeeded for the first time in measuring the viscosity that molten solids exhibit under the pressure and temperature conditions found in the lower earth mantle. The data obtained support the assumption that a bridgmanite-enriched rock layer was formed during the early history of the earth at a depth of around 1,000 kilometres—at the border to the upper mantle. In addition, the data also provide indications that the lower mantle contains larger reservoirs of materials that originated in an early magma ocean and have remained unchanged to this day. The researchers have presented their findings in the scientific journal Nature Communications.