A method for estimating volcanic gas emission based on acoustical features of volcanic fumaroles

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K03992
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17030:Human geosciences-related
• Research Institution: Kyoto University
• Principal Investigator: Yokoo Akihiko 京都大学, 理学研究科, 准教授 (70420403)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 阿蘇山 / 火山 / 空振 / 噴火 / 火山ガス / 無人航空機

Outline of Final Research Achievements

Due to several reasons, including the higher level of volcanic activity at the Nakadake first crater of Aso volcano, severe damage to infrasound stations caused by phreatic explosions in October 2020, and known mechanical problems on a thermal camera deployed on the unmanned aerial system that has newly purchased by this fund, we were forced to change the primally study plan of this research. However, we obtained fundamental results that will contribute to the improvement of volcanic monitoring, which is the goal of this study. They were the operations of an unoccupied aerial system leading to understanding detailed changes in crater topography, the spatial distribution of volcanic bombs due to the 2020 explosion, sampling of volcanic gases, improving the analytical methodology of the thermal data, and waveform inversions of infrasound pulses frequently observed before phreatic explosions.

Free Research Field

火山学

Academic Significance and Societal Importance of the Research Achievements

噴火が発生すると立ち入り禁止区域が設定され、この外から火山活動状況を把握することが要請される。本研究では、噴火中の阿蘇山でドローンを使用したさまざまな観測を試行し、火口地形変化や噴出物の飛散範囲を把握することに成功した。また、火山ガスサンプリングや熱データ解析法の高精度化でも成果を上げた。また、空振データ波形解析を準リアルタイムで行えば水蒸気爆発発生を予見できるかもしれないことを見出した。