2024年7月26日にオンラインで第10回岩石ー流体セミナーが開かれました。講演者は、新潟大学のサティシュクマール教授で、インドのグラファイト脈の同位体や組織の特徴についての講演でした。参加者11名で、活発な議論が行われました。
Graphite vein formation process and carbon sequestration in continental crust
M. Satish-Kumar (Niigata University)
Abstract
Graphite is a common accessory mineral in continental crust. Graphite forms in the crust mainly through graphitization of organic carbon during metamorphism. Graphite can also form by precipitation from carbon saturated fluids. In this presentation I review the characteristics of vein type graphite and their formation mechanisms based on fluid inclusion studies and carbon isotopic compositions. Case studies from Sri Lanka and East Antarctica will be discussed. The topics of discussion includes how COH(S) fluids evolve in crust; graphite oxidation vs graphite precipitation; whether graphite in the crust plays a role in carbon sequestration or CO2 emission to atmosphere.