水中爆発の規模と特性の定量的評価

水下爆炸规模和特征的定量评估

• 批准号: 07226203
• 负责人: 大島 弘光
• 金额: $ 1.09万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-07226203/
• 关键词: 蒸気爆発; 海底噴火; 空気振動; 火山観測

水中爆発や海底・湖底火山噴火の規模や特性を評価するための指針を得ることをめざして,火薬玉(号砲)を爆発源とした水中爆破実験を行った.実験では,(1)爆破水深,(2)爆点-観測点間距離を変えて爆破を行った.観測には,通常の火山観測で使用されている地震計,空振計に加えハイドロフォン,ビエゾ水中衝撃波計を水中に,またビデオを地上に設置した.観測された水中音波は複雑な波形を示し,直達波の到着直後でさえ水面反射波と見られる位相の混入が認められた.直達波振幅については,理論値よりもかなり小さく,爆破水深や爆点-観測点間距離による違いは認められなかった.これに対して地震波の初動振幅は,頭打ちにはなるが,爆破水深にほぼ比例関係が認められた.爆破水深が浅い場合には水柱(またはwater dome)が形成され,その高さは爆破水深に対して比例ないしべき関数的な減少傾向を示した.水柱が形成される場合には空気振動が観測され,その振幅は爆破水深に対してべき関数的に減少し,さらに周期もやや延び,水柱の形成が空気振動を励起していることが示唆された.水柱音波振幅に発破深度や距離依存性が認められなかったことや地動振幅と水注音波振幅の不調和は,観測方法に起因していると考えられ,今後の実験方針を立てうるうえで問題点が明らかになった.また,湖底・海底噴火の時間スケールは未知だがこれらを対象とした火山観測に新たな問題が提起された.その一方で,水柱を伴う湖底・海底噴火に対しても空気振動観測が有効であることが示唆された.

The characteristics of the fire pattern of the volcano at the bottom of the sea and the bottom of the lake in the water means that the fire is in the water, the source of the explosion is the source of the explosion, and the source of the explosion is the source of explosion. Blasting depth, (1) blasting water depth, (2) blasting point-measuring point distance from blasting point to blasting depth. In general, the volcano uses a log to measure the seismometer, the air vibrometer is added to the meter, the wave in the water is measured to measure the temperature in the water, and the trap is set on the ground. The sound waves in the water are copied and the waveforms are displayed, and the phase of the reflected waves on the water surface is mixed with the waves in the water. The amplitude of the direct wave, the depth of the blasting water depth, the burst point of the blasting water depth, the distance of the measuring point, the distance of the measuring point. The amplitude of the initial motion of the seismic wave is measured, the amplitude of the initial motion of the seismic wave is measured, the amplitude of the initial motion of the seismic wave is measured, the amplitude of the initial motion of the seismic wave is measured, the amplitude of the initial motion of the seismic wave is measured, the amplitude of the initial motion of the seismic wave is measured, and the ratio of the water depth of blasting is measured. The blasting water depth is shallow and close to the water column (water dome) to form a water column, and the ratio of the blasting water depth to the height of the blasting water depth is less than that of the number of blasting water. The frequency of the water column is low, and the cycle of the water column is lengthened, and the water column is formed. The air vibration is caused by the air vibration, the air vibration is activated, and the frequency is instigated. The amplitude of the water column sound wave is different from the depth of the water column sound wave, the amplitude of the water injection sound wave is different from the amplitude of the water injection sound wave, the amplitude of the water injection sound wave is different from the amplitude of the water column sound wave, the amplitude of the water column sound wave is different from that of the water column sound wave. At the bottom of the lake, there is a fire at the bottom of the lake. the time for fire at the bottom of the lake, the sea floor, the sea, the fire, the fire at the bottom of the lake, the fire at the bottom of the lake. On one side, the water column accompanied by the fire at the bottom of the lake, the air vibration, the air vibration, the fire, the air, the air, the air,

项目成果

大島 弘光: "爆発的噴火の規模評価の試み" シンポジウム「火山爆発と蒸気爆発」. 94-96 (1995)

大岛宏光：“尝试评估爆炸性喷发的规模”研讨会“火山爆炸和蒸汽爆炸”94-96（1995）。