Volcanic Earthquakes and Tremor at Kilauea Volcano : Source Mechanisim in Relation to Volcano Structure Eruptive Processes

点击翻译按钮获取中文摘要

The cooperative experiment with U. S. volcanologists was conducted around the summit area of Kilauea volcano, Hawaii. Over a five day period three seismic antennas, three temporary broadband stations added to the seven permanent broadband stations, and a 120-component seismic reflection line were installed. During the experiment, Kilauea Volcano was undergoing an unusual period of seismic activity associated with a protracted transient in 10-year-long Puu Oo eruption. Analyzing the data of this experiment, some features of the seismic events are clarified as are summarized below.The crustal deformation accompanied with the very-long period pulses was observed. Particle motion plots for the pulses indicate that the source of these signals originated near the north rim of the summit crater. Since the crustal deformation is thought to be caused by the magma activities just blow the crater, the very-long-seismic signals may be related to the magma activities. The source mechanism of the crustal deformation and the seismic pulses will be clarified by the detailed analysis of the data newly obtained by the broadband stations.During the experiment, many volcanic earthquakes were observed. Frequency-slowness array analyses of volcanic signals by way of MUSIC method present that the signals came from the summit crater. Precise analyses of the data with the seismic antennas will show the detailed nature of the waveforms of the seismic events and the underground structure below the summit area.