|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Hume-Rothery Award Symposium: Computational Thermodynamics and Its Implications to Kinetics, Properties, and Materials Design
||Thermodynamic Modeling of the History of 3.45-billion-year-old Meteorites
||Hiroshi Ohmoto, Uschi M. Graham, Takeshi Kakegawa, Zi-Kui Liu
|On-Site Speaker (Planned)
Geochemists have estimated the ages and compositions of the Earth and the Solar system mostly from the ages (~4.56 Byr) and compositions of meteorites that fell recently (<1 Myr) on Earth. We have discovered abundant meteorite fragments trapped in basalt lavas in Western Australia that erupted on a deep ocean floor ~3.45 Byr ago. Their mineralogy and chemistry are uniquely different from the modern meteorites, suggesting that the Earth may have formed at >4.56 Byr by asteroids from a different part of the Solar system compared to the modern meteorites. We have performed thermodynamic modeling of: (1) cooling history of the presumed parental planet of the meteorites, and (2) chemical reactions between the meteorites and the atmosphere. The results agree with the observed mineralogy of the meteorites, and put constraints on the compositions of the Earth and the Solar system and on the oxygen contents of the 3.45 Byr atmosphere.
||Planned: Supplemental Proceedings volume