北京高压科学研究中心
Center for High Pressure Science &Technology Advanced Research

Li Zhang published a paper in SCIENCE


On May 23, 2014, a paper entitled "Disproportionation of (Mg,Fe)SiO3 perovskite in Earth's deep lower mantle", written by Dr. Li Zhang and co-workers, was published in SCIENCE magazine. Dr. Li Zhang is a staff scientist of HPSTAR @ Shanghai. She got the "Thousand Young Talents Fellowship" from Chinese Central Organization in 2013.


The mineralogical constitution of the Earth's mantle dictates the geophysical and geochemical properties of this region. Previous models of a perovskite-dominant lower mantle have been built on the assumption that the entire lower mantle down to the top of the D″layer contains ferromagnesian silicate [(Mg,Fe)SiO3] with nominally 10 mole percent Fe. On the basis of experiments with laser-heated diamond anvil cells, at pressures of 95 to 101 gigapascals and temperatures of 2200 to 2400 kelvin, Dr. Li Zhang and her research group found that such perovskite is unstable: it loses its Fe and disproportionates to a nearly Fe-free MgSiO3 perovskite phase and a Fe-rich phase with a hexagonal structure. This observation has implications for enigmatic seismic features beyond ~2000 kilometers depth and suggests that the lower mantle may contain previously unidentified major phases.


Since its publication, lots of international and domestic renowned media agencies have reported this research work.