[M-GI29] Data-driven geosciences

[MGI29-P01] An Interdisciplinary approach to construct a three-dimensional chemical composition model of the Japan crust toward global geochemical observation using geoneutrino

*Kenta Ueki¹, Akiko Tanaka², Sanshiro Enomoto^3,4, Nozomu Takeuchi⁴, Tsuyoshi Iizuka⁴, Satoru Haraguchi⁴, Hiroko Watanabe⁵, Tsutomu Fukuda⁶ (1.Japan Agency for Marine-Earth Science and Technology, 2.National Institute of Advanced Industrial Science and Technology, 3.University of Washington, 4.The University of Tokyo, 5.Tohoku University, 6.Nagoya University)

Keywords:Geoneutrino, Japan crust

Geoneutrinos, antineutrinos from radioactive decays of uranium (U) and thorium (Th) inside the Earth are direct observational data to constrain the whole solid Earth composition and, therefore, provide essential constraints on the formation and chemical and thermal evolution processes of the solid Earth. Geoneutrino flux has been determined with high precision by the KamLAND detector in Kamioka, Gifu Prefecture, Japan. Since the observed geoneutrino flux involves contributions from both the crust and mantle, it is necessary to subtract the local crust flux from the total flux in order to constrain the chemical composition of the deep Earth. Despite the high accuracy of the KamLAND geoneutrino observation, it has not been possible to precisely constrain the mantle composition due to the large uncertainty of the estimated geoneutrino flux from the Japan crust. This study aims to quantitatively estimate the three-dimensional distribution of U and Th in the Japan crust to determine the geoneutrino flux from the Japan crust precisely. We have been conducting an interdisciplinary study integrating geology, geochemistry, geophysics, and high-energy physics. We will introduce the latest research status, including a strategy for constructing a high-precision 3D chemical composition model of the Japan crust that integrates information on geochemistry, seismic velocity structure, and geological maps, and the development of a new technology for precisely determining the distribution of radioactive elements in rock samples.