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近震波形尾波的早期部分通常以多次散射波占优势。地下介质的微小变化对初至的影响无法检测出,但多次散射波可放大这些变化,进而可在尾波中观察到这些变化。根据这一想法本文使用尾波干涉法来监测南极埃里伯斯火山的瞬态变化。埃里伯斯火山是地球上少数几个拥有长时间对流岩浆湖的火山之一。析出的巨大气泡的破裂造成斯通博利式的喷发,这些爆发活动提供了使得地震能量沿极为松散的火山介质传播的重复的震源。我们检查了1999年12月到2000年2月持续2个月喷发活动的信号,发现在整个喷发期间,地震图的开始部分高度地重复。第一个月里,尾波部分也是如此,但大约过了一半时间,地震尾波在几天的时间内变得不相关。这表明火山散射特性的快速变化,很可能反映了用直接或单次散射地震波理论无法识别的火山顶岩浆管道系统细微的变化。
Early parts of near-wavy coda usually dominate multiple scattered waves. The small change in subterranean media can not detect the effect of the first arrival, but multiple scattering waves amplify these changes, which can be observed in the wake. Based on this idea, this paper uses coda interferometry to monitor the transient changes of the Eritrean Antarctic volcano. The Ereborris volcano is one of the few volcanoes on Earth that have long convective magma lakes. The rupture of the giant bubbles precipitated resulted in the Stonecutter eruption, which provided a repeating source of seismic energy that transmitted seismic energy along the extremely loose volcanic media. We examined signals of eruptions that lasted two months from December 1999 to February 2000 and found that the beginning of the seismogram was highly repeated throughout the eruption. In the first month, too, the coda part did so, but after about half the time, the coda wave became irrelevant for several days. This indicates that rapid changes in volcanic scatter characteristics most likely reflect the subtle changes in the volcanic top magmatic pipeline system that are unidentifiable by either direct or singularly-scattered seismic wave theory.