Meteoritic carbonate synthesis constrained by carbon isotope compositions

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K18725
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 17:Earth and planetary science and related fields
• Research Institution: Tohoku University
• Principal Investigator: Furukawa Yoshihiro 東北大学, 理学研究科, 准教授 (00544107)
• Co-Investigator(Kenkyū-buntansha): 石田 章純 東北大学, 理学研究科, 助教 (10633638) ; 高柳 栄子 東北大学, 理学研究科, 准教授 (40729208)
• Project Period (FY): 2022-06-30 – 2024-03-31
• Keywords: 炭酸塩

Outline of Final Research Achievements

Aqueously-altered meteorites and asteroids contain organic matter such as amino acids and sugars, which may have contributed to the supply of life's building blocks to the Earth. Such meteorites also contain carbonates with a wide range of carbon isotopic compositions enriched in 13C. In this study, we focused on the fact that formose-type reactions using aldehydes as a carbon source produce amino acids and sugars, and that these reactions are catalyzed by calcium.
Various Formose-type reaction experiments were performed to identify the carbonates produced. The results showed that the carbonate produced was calcite, and that the calcite carbon was enriched in 13C compared to the insoluble organic matter produced at the same time. On the other hand, the extent of 13C enrichment is not enough to explain the wide range of 13C-rich carbon isotopic compositions found in the meteorites. Mixing with highly 13C enriched CO2 in asteroids may explain the wide range of 13C enrichments.

Free Research Field

地球宇宙化学

Academic Significance and Societal Importance of the Research Achievements

本研究では隕石や小惑星に含まれる炭素の形態の形態の一つである炭酸塩の起源に関して、新たな説を提供し、その説によって生成する炭酸塩の炭素同位体組成を制約した。その結果、この炭素源の寄与はありうるが、全てがこの起源では説明できないことが明らかになった。