Investigationo of Nitrogen Cycle from the Earth's Surface to the Deep Interior by the Formation of Metamorphic Diamonds

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K14808
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17040:Solid earth sciences-related
• Research Institution: Hokkaido University
• Principal Investigator: Shinozaki Ayako 北海道大学, 理学研究院, 助教 (80570506)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 沈み込み帯 / 窒素 / 芳香族化合物 / ダイヤモンドアンビルセル / ピストンシリンダー / GCMS

Outline of Final Research Achievements

Subducting slab is the only place where materials are supplied from the Earth's surface to the Earth's interior, and are particularly important region for understanding the global nitrogen cycle. The objective of this project was to clarify the behavior of nitrogen in the slab. In particular, we focused on sedimentary organic materials and C-O-H-N fluids, which are an important reservoir of nitrogen and are pointed out to have a possible origin of metamorphic diamonds. High-temperature and high-pressure experiments were conducted to investigate the details of chemical reactions of several organic compounds in the conditions of slab.

Free Research Field

高圧科学

Academic Significance and Societal Importance of the Research Achievements

窒素は地球表層大気から地球内部のマントル、核まで様々な場所で存在し、その存在状態も多種多様である。窒素は地球の進化に影響する重要な元素だが、全地球規模で循環に関しては未解明な点が数多く残されている。沈み込むスラブは、地球表層から深部へと物質が供給される唯一の場所であり、全地球規での窒素循環を考えるうえで特に重要な領域である。本研究の成果から全地球規模での窒素循環への理解が進むことによって、地球の進化に関するさらなる知見が得られることが期待される。