权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

マグマ過剰圧とその時間変化の追跡による爆発的割れ目噴火推移過程の解明

通过跟踪岩浆超压及其时间变化来阐明裂隙喷发的转变过程

基本信息

批准号：
22K03785
负责人：
下司信夫
金额：
$ 2.58万
依托单位：
National Institute of Advanced Industrial Science and Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2022
资助国家：
日本
起止时间：
2022-04-01 至 2025-03-31
项目状态：
未结题

项目摘要

桜島の代表的な割れ目噴火である大正噴火、安永噴火、文明噴火の噴出物の層序解析による噴火推移の把握を行うとともに、層序に沿って試料を採取し、その時間変化を解析した．大正噴火の噴出物は桜島の東部黒神地区および西部の湯ノ平地区で、東西の火口列の試料をそれぞれ採取した．また、噴火後に急冷された細粒粒子の試料を採取するため、桜島東方に離れた牛根地区で追加試料採取を行った．桜島東部においては、大正噴火の初期噴出層である降下軽石と、それを覆う後期噴出物である軽石質火山砂層の噴出物を識別し、それぞれの代表的な試料の採取を行った．安永噴火噴出物は牛根地区で降下軽石を３層準から採取した．また文明噴火噴出物は、桜島島北東にあたる福山地区で層序に沿った試料を3層準から採取を行った．桜島大正噴火の噴出物のガラス包有物の含水量とその水拡散プロファイルを取得し、噴火層序に沿って5試料を比較した．ガラス含水量は、EDSを用いた酸素定量による含水量推定方法を用いた．ガラス湾入部の含水量変化を32プロファイル取得し、マグマ噴出時の温度・ガラス化学組成から推測されるシリケイトメルト中の水の拡散速度を用いて、プロファイルから推測される平均的な減圧速度を推測した．その結果、爆発性の高い初期の軽石噴火ステージでは比較的高いマグマ過剰圧力を保持していたのに対し、軽石噴火に引き続く火山灰放出ステージの噴出物では過剰圧が低下し、低い減圧速度で噴出していたことが判明した．軽石噴火ステージ内での時間変化ははっきりとした傾向を見出すことは難しかった．

The order of the products produced by the fire, Ernst & Young, and civilization is analyzed in order to understand the process of the fire, to collect the goods along the materials, and to analyze them in time. Dazhong exports the goods to the black god area in the western part of the country. In the west of the fire, the materials were collected. After the fire, the particles were collected, and the cow root area was added to the cowroot area. in the first part of the fire, there was a drop of stone in the early stage of the fire, and after the fire, the products were collected from the volcanic sand after the fire. The material represented by the EY fire, the Niugen area, lowered the stone from the Niugen area, dropped the stone from the Niugen area, and took it from the Fukuyama area in the Fukuyama area. in the order of the material, the water, the water. The water content of EDS is determined by the method of quantitative determination of water content. The water content of the inlet of the bay is determined by the temperature of 32 ℃, and the temperature is determined by the chemical composition of the temperature at the temperature of the temperature. The speed of water dispersion in the temperature range is determined by the method of determining the water content in the inlet of the bay. The results of the experiment, the high temperature temperature at the early stage of the explosive high temperature, the high temperature temperature at the early stage of the explosive high temperature, the high temperature at the early stage of the explosive high temperature, the high temperature at the early stage of the explosive high temperature, the high temperature at the early stage of the explosive high temperature, the high temperature at the early stage of the explosive high temperature, the temperature at the early stage of the explosion, the temperature at the early stage of the explosion, the temperature at the early stage of the explosion, the temperature at the early stage of the explosion, the temperature at the beginning of the explosion, the temperature at the beginning of the explosion, the temperature at the beginning of the explosion, the temperature, the temperature At a low speed, it is possible to determine the temperature of the aircraft. the temperature in the fire is changed in the temperature range, and the temperature is not clear.