Deciphering CO Geochemistry on Early Earth and Mars

The Geochemistry Group will reconstruct the early environments of Earth and Mars. In order to decipher past atmospheric chemistry, biological activities, and inorganic synthesis processes that cannot be directly observed, the Geochemistry Group will develop stable isotope ratio measurement methods at the molecular level (isotope molecular measurement). The group will characterize the isotopic molecular composition of organic molecules produced by atmospheric, biological, and chemical processes, and establish indicators (biomarkers) to discriminate between organic molecules produced from CO by atmospheric chemistry and biological processes. The chemical processes of atmospheric CO will be elucidated through observations of the Martian atmosphere and photochemical experiments in the laboratory, and the organic molecules supplied by the CO atmosphere and their isotopic fractionation will be characterized. In addition, the biological processes will be observed in the extreme CO environment in collaboration with the biology group, and isotopic molecular measurements will be applied to elucidate the material cycle in the early terrestrial analog environment and to demonstrate the usefulness of the biological indicators. Using the above isotopic indicators and the atmospheric model constructed in collaboration with the theory group, we will analyze isotopic anomalies of organic molecules in Earth's historical rock samples and Martian meteorites to elucidate material cycles on the early Earth and Mars, starting from atmospheric CO, and decipher their early planetary environments, including the presence or absence of life.




Members
Ueno Yuichiro  (PI), Tokyo Tech., Department of Earth and Planetary Sciences, Professor
Yamada Keita,          Tokyo Tech., School of Materials and Chemical Technology, Associate Professor
Aoki Shohei,            Tokyo University, Graduate School of Frontier Science, Lecturer
Gilbert Alexis,          Tokyo Tech., Department of Earth and Planetary Sciences, Associate Professor