R8：変成岩とテクトニクス

[R8-15] Occurrence of CH₄–N₂-bearing aqueous fluid inclusions in jadeite-bearing chlorite–grossular rock from the New Idria serpentinite body, California

*Rio Rio¹, Tatsuki Tsujimori¹ (1. Tohoku University)

キーワード：Jadeite, fluid inclusion, nitrogen, methane, serpentine

Primary fluid inclusions in the jadeite-bearing chlorite-grossular rock from the New Idria serpentinite body, central California, were studied and three groups of fluids (mixed CH₄–H₂O, CH₄–N₂–H₂O, and N₂–H₂O) were identified. CH₄ can correlate to a serpentinization process and N₂ was most likely derived from the subducted sediments. This presentation will report the occurrence of the CH₄–N₂-bearing aqueous fluid inclusions and discuss the possible source of nitrogen.