Modeling of explosive subaqueous eruptions

2016 Fiscal Year Final Research Report

• Project/Area Number: 26400491
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Geology
• Research Institution: Kagoshima University
• Principal Investigator: Kano Kazuhiko 鹿児島大学, 総合研究博物館, 教授 (40356811)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 爆発的水底噴火 / マグマ水蒸気噴火 / 水蒸気噴火 / ジェット粉砕 / 水冷破砕 / 水和 / 気孔数密度 / 粒径分布

Outline of Final Research Achievements

Water-chilled bombs collected from the Miocene deep marine successions of the Shimane Peninsula have a vesicle-number density distribution and a porosity indicative of a Strombolian-like eruptive process. In a Miocene shallow-marine pyroclastic cone of the same Peninsula, scoria-agglutinate fills the conduit but the correlative eruption-fed scoria-density-current deposits are much finer-grained with minor projectiles, suggesting water-ingestion and explosive water-particle interactions in the plumes or currents. Pyroclastic density current deposits from Katsumayama volcano are composed mainly of rhyolitic perlite clasts, being produced through water quenching, hydration-induced cracking and explosive heating water to steam. These case studies show external water play an important role in explosive subaqueous eruptions.

Free Research Field

火山地質学