『Abstract
　We propose a new model of Earth's bulk composition based on enstatite chondrites (E-chondrites), the only chondrite group isotopically identical to the Earth. This model allows a quantitative study of accretion and differentiation processes in the early Earth. Conditions for core formation are evaluated using data on silica-iron equilibrium at high pressure and temperature and the exchange budget equation SiO2 + 2Fe = Si + 2FeO, which is the result of IW and Si-SiO2 oxygen buffers' interaction and controls the evolution of mantle fO2. Based on that equation, ranges for the compositions of the Bulk Silicate Earth, the lower mantle and the core are deduced from the compositions of E-chondrites and their constituents. For these ranges of compositions, we show that during core differentiation, the mantle fO2 evolves naturally from ≒IW -3.2 to IW -1.4±0.1. The model compositions are tightened using geophysical constraints on (1) the amount of light elements in the core, (2) the petrology of the upper and lower mantle and (3) the thermal and convective structure of the lower mantle. Our results indicate that the lower mantle is enriched in Si and Fe, which is consistent with recent geophysical studies, and depleted in highly refractory elements, notably in Uranium and Thorium.

Keywords: chemical earth models; enstatite chondrites; Redox state; isotopic anomalies; core composition; heterogeneous mantle; early Earth; radioactive heating』

1. Introduction
2. Enstatite chondrites
　2.1. The isotopic parenthood of Earth and E-chondrites
　2.2. The space of E-chondrite compositions
　2.3. Critical features of E-chondrites for Earth modeling
3. Composition of the Bulk Silicate Earth and of the core
　3.1. Internal Redox evolution
　3.2. Calculation of the core and mantle compositions
　3.3. Average core and mantle compositions
　3.4. Average P-T conditions of core formation
　3.5. Lower mantle composition
4. Geophysical constraints
　4.1. Light elements in the core: experimental results and ab initio calculations
　4.2. Bulk mantle composition: seismological and geodynamical constraints
5. Discussion and perspectives: composition and dynamics of the Earth
　5.1. The heterogeneous mantle
　5.2. RLE enrichment factor and volatility of elements during Earth formation
　5.3. Heat production in the lower mantle
　5.4. Origin of mantle chemical heterogeneity
　5.5. The way to future experimental tests of E-Earth model
6. Conclusion
Acknowledgements
References