Dating of mantle derived peridotite: development of neutrino-dating of olivine

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K20944
• 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: Nagoya University
• Principal Investigator: Kato Takenori 名古屋大学, 宇宙地球環境研究所, 准教授 (90293688)
• Co-Investigator(Kenkyū-buntansha): 中 竜大 東邦大学, 理学部, 講師 (00608888) ; 伊神 洋平 京都大学, 理学研究科, 助教 (30816020) ; 小坂 由紀子 高知大学, 海洋コア総合研究センター, 研究員 (90847360)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: マントル / 素粒子 / 飛跡 / カンラン石 / 白雲母 / 阻止能 / 年代測定

Outline of Final Research Achievements

A principle demonstration study was conducted to estimate the formation age of the mantle by focusing on the interaction between subatomic particles and minerals. First, ICP-MS analysis revealed that the uranium concentration in peridotite was significantly low. Additionally, observation of samples subjected to irradiation experiments suggested the potential of subatomic particles leaving tracks.
The development of a method to distinguish tracks formed by ionization stopping power and nuclear stopping power, along with the evaluation of detection efficiency, would allow for the determination of the interaction duration between peridotite and neutrinos. With the calibration of detection efficiency, it is believed that the absolute dating of the mantle could be realized.

Free Research Field

地質年代学

Academic Significance and Societal Importance of the Research Achievements

本研究成果はマントルの絶対年代測定の可能性を示すものであり、プレート運動と駆動機構の時間変化や、地殻・マントル間での物質移動を理解するうえで必要不可欠な情報を与えることが可能になると期待できる。また、本研究で用いた手法はニュートリノ以外の素粒子にも応用可能であり、暗黒物質の直接探索を可能にする可能性がある。