Japan Geoscience Union Meeting 2025

Presentation information

[J] Oral

H (Human Geosciences ) » H-CG Complex & General

[H-CG22] Monitoring the Comprehensive Nuclear-Test-Ban Treaty: Status, operations, and scientific application

Tue. May 27, 2025 10:45 AM - 12:15 PM 104 (International Conference Hall, Makuhari Messe)

convener:Dirk Metz(CTBTO), Satoru Endo(Graduate School of Advanced Science and Engineering,Hiroshima University), Hiroyuki Matsumoto(Japan Agency for Marine-Earth Science and Technology), Takayuki Otsu(Japan Weather Association), Chairperson:Satoru Endo(Graduate School of Advanced Science and Engineering,Hiroshima University), Yasuhito Igarashi(Institute for Integrated Radiation and Nuclear Science, Kyoto University)

11:30 AM - 11:45 AM

[HCG22-10] Inventory distribution of radionuclides in unaltered soil samples

*Hiroshi Yashima1, Yasuhito Igarashi1, Takashi Saito2, Naofumi Akata3, Sumi Yokoyama4, Satoru Endo5, Yayoi Inomata6, Shinji Sugihara7, WG Meteorology and Soil (1.Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2.SHOKEI GAKUIN UNIVERSITY, 3.Hirosaki University, 4.Nagasaki University, 5.Hiroshima University, 6.Kanazawa University, 7.Oita University)

Keywords:Inventory of radionuclides, alteration of soil samples

Soil samples are being collected to obtain validation data for the "black rain" deposition in the study of the estimated "black rain" rainfall area that occurred after the atomic bombings of Hiroshima and Nagasaki in 1945. In order to confirm whether the validation data obtained are from the 1945 deposition, it is necessary to confirm that the soil samples have not been altered and that the stratigraphy has been preserved.
We reported on the evaluation of alteration of soil samples using radioactivity distribution profiles in soil samples and fallout inventories. Even at points where the inventory amount fell outside the judgment criteria, the profiles were neatly distributed and there were also points that appeared to be unaltered, so the inventory amount conditions were reviewed. In this presentation, we report on the reviewed conditions of inventory.