Chemical composition and thermal state of the present Earth's interior is the results of integration of various drastic processes in the past. For instance, it has long been known that the formation of the core transforms gravitational energy into heat and is able to heat up the whole Earth by about 2000 K. However, the distribution of this energy within the Earth is still debated and depends on the core formation process considered. Iron rain in the surface magma ocean is supposed to be the first mechanism of separation for large planets, iron then coalesces to form a pond at the base of the magma ocean. In this process, equilibrium between metal and silicate is achieved within several seconds [1]. The numerical simulations of thermal and chemical evolution of the magma ocean using partition coefficients obtained by high P, T experiments can be used to estimate the compositions of the mantle and the core just after their formation. The results of these numerical simulation also can be compared to the present core composition independently constrained by the comparison between seismic observations and material properties [2-5]. In this seminar, I will introduce my past researches related to the chemical and thermal evolution of the Earth along with my future research plan. The results of wide-range of research topics will be synthesized and help understand the evolution of the solid Earth in more detail.

[1] Ichikawa et al. (2010) JGR 115, B01404. [2] Badro et al. (2014) PNAS 111, 7542-7545. [3] Ichikawa et al. (2014) JGR 119, 240-252. [4] Umemoto et al. (2014) GRL 41, 6712-6717. [5] Umemoto & Hirose (2015) GRL 42, 7513-7520.