Source mechanism of volcanic tremor revealed by waveform analyzes and fluid-dynamic experiments

波形分析和流体动力学实验揭示火山震源机制

• 批准号: 07640547
• 负责人: IDA Yoshiaki
• 金额: $ 1.47万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640547/
• 关键词: Volcanic earthquake; Volcanic tremor; Asama volcano; A-type earthquake; B-type earthquake; N-type earthquake; 震源分布; 浅間山; 低周波地震; 草津白根山; 発生機構; スペクトル; 微動発生機構

Good waveform data of volcanic earthquakes and tremor have been obtained from continuous observations at four stations that were newly installed very close to the summit crater of Asama volcano in October, 1996. Adding the data to those from the older stations surrounding the summit in greater distances, the natures of volcanic earthquakes and tremor have been understood much better, as are summarized below.Hypocenters of the volcanic earthquakes (B-type earthquakes) and tremor (low frequency or N-type event) just bellow the summit crater have turned out to be much shallower and more concentrated into a narrow region than believed previously. Other earthquakes below the west flank (A-type earthauake) tend to be distributed on the same line as these shallow events with some seismic gap between the two groups.The S-wave phases of the shallow B-type events below the crater were quite ambiguous in the waveforms from the older stations, but they are identified more clearly in those obtained from the new stations near the crater. The waveform of the tremor (low frequency or N-type event) has a sharp rise at the ***set and it is usable to separate part of the excitiaion from the part of resonance.

从连续观察到的四个站点的连续观察获得了良好的波形数据，这些站点非常接近1996年10月，这些站点非常接近Asama火山的山顶山口。将数据添加到围绕山顶的较旧站的人中，距离更远的山顶，更远的距离，伏尔可以进行的北极地震和震颤的表现更好，这是在下面的众多景象。 （B型地震）和震颤（低频或n型事件）只是bellow山顶火山口比以前认为的较浅，更集中到一个狭窄的区域。西侧侧面下方的其他地震（A型Earthauake）倾向于在与这些浅层事件的同一线上分布，并在两组之间具有一定的地震差距。越野火山口下浅B型事件的S波阶段在较旧的车站的波形中非常模棱两可，但在较旧的车站中，它们在附近获得的那些人中得到了更清晰的识别。震颤的波形（低频或n型事件）在***集合时具有急剧上升，并且可以将兴奋的一部分与共振部分分开。

项目成果

辻浩: "浅間火山の山頂地震観測" 技術研究報告(東京大学地震研究所). NO.2. 135-140 (1997)

辻宏：《浅间火山山顶地震观测》技术研究报告（东京大学地震研究所）NO.2（1997）。

藤田英輔,井田喜明,及川純: "Ergen oscillation of a fluid sphere and source mechanism of monochromatic volcanic tremor" J.Volcanol.Geothem.Res.(印刷中).

Eisuke Fujita、Yoshiaki Ida、Jun Oikawa：“流体球的 Ergen 振荡和单色火山震源机制”J. Geothem Res。

Hiroshi Tsuji: "Seismic observation around the summit area of Asama volcano" Technical Research Report. NO.2. 135-140 (1997)

Hiroshi Tsuji：“浅间火山山顶地区周围的地震观测”技术研究报告。