Trends in the aggregated rate of pre-eruptive volcano-tectonic seismicity at Kilauea volcano, Hawaii
Trends in the aggregated rate of pre-eruptive volcano-tectonic seismicity at Kilauea volcano, Hawaii
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夏威夷基拉韦厄火山喷发前火山构造地震活动的总速率趋势
DOI：
10.1007/s00445-012-0677-y
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发表时间：
2013
影响因子：
3.5
通讯作者：
Bell A
中科院分区：
文献类型：
--
作者：
Bell A
火山构造（VT）地震的加速速率通常在火山不动期间观察到。了解它们行为的可重复性对于评估它们预测火山爆发的潜力至关重要。定量喷发预测集中在几周或更短时间内的前兆变化。先前对频繁喷发的玄武岩火山的研究，如夏威夷的基拉韦厄火山和r<s:1>上的皮顿德拉福尔奈斯火山，表明在火山喷发前2周左右，VT地震率倾向于遵循幂律加速度，但这种趋势往往被VT地震率的随机波动（或噪音）所掩盖。这些先前的研究使用了一种叠加程序，其中几次火山爆发的前兆序列结合在一起，以增强来自VT地震速率潜在加速的信号。这种分析假定所有火山爆发都有一个共同的前兆趋势。这一假设在这里得到了验证，在1959年至1984年间，基拉韦厄火山记录了57次喷发和侵入。应用严格的数据选择标准（例如，最大深度；限制震级大于完整震级2.1），我们发现总的地震率的增加比以前报道的要少得多。叠置趋势还受到一个特定的喷发前层序的行为的强烈控制。相比之下，一个强大的信号出现在叠加的VT地震率中，这是火山喷发和侵入的一个子集。这些结果与基拉韦厄火山的两种不同的前兆类型是一致的：(1)少量的喷发和侵入在几周到几个月的间隔内伴随着VT级地震的加速发生；(2)大量的喷发直到几小时前才显示出持续的增加。这些结果也证实了根据简单的空间分布和完整震级约束过滤的数据来检验前兆趋势的重要性。
Accelerating rates of volcano-tectonic (VT) earthquakes are commonly observed during volcanic unrest. Understanding the repeatability of their behaviour is essential to evaluating their potential to forecast eruptions. Quantitative eruption forecasts have focused on changes in precursors over intervals of weeks or less. Previous studies at basaltic volcanoes in frequent eruption, such as Kilauea in Hawaii and Piton de La Fournaise on Réunion, suggest that VT earthquake rates tend to follow a power-law acceleration with time about 2 weeks before eruption, but that this trend is often obscured by random fluctuations (or noise) in VT earthquake rate. These previous studies used a stacking procedure, in which precursory sequences for several eruptions are combined to enhance the signal from an underlying acceleration in VT earthquake rate. Such analyses assume a common precursory trend for all eruptions. This assumption is tested here for the 57 eruptions and intrusions recorded at Kilauea between 1959 and 1984. Applying rigorous criteria for selecting data (e.g. maximum depth; restricting magnitudes to be greater than the completeness magnitude, 2.1), we find a much less pronounced increase in the aggregate rate of earthquakes than previously reported. The stacked trend is also strongly controlled by the behaviour of one particular pre-eruptive sequence. In contrast, a robust signal emerges among stacked VT earthquake rates for a subset of the eruptions and intrusions. The results are consistent with two different precursory styles at Kilauea: (1) a small proportion of eruptions and intrusions that are preceded by accelerating rates of VT earthquakes over intervals of weeks to months and (2) a much larger number of eruptions that show no consistent increase until a few hours beforehand. The results also confirm the importance of testing precursory trends against data that have been filtered according to simple constraints on the spatial distribution and completeness magnitude of the VT earthquakes.
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影响因子：
2.8
作者：
A. Bell;J. Greenhough;M. Heap;I. Main
通讯作者：
A. Bell;J. Greenhough;M. Heap;I. Main
玄武岩火山的解剖
影响因子：
64.8
作者：
R. Tilling;J. Dvorak
通讯作者：
J. Dvorak
三座玄武岩火山岩浆堆积引起的地震活动和变形
影响因子：
--
作者：
O. Lengliné;D. Marsan;J. Got;V. Pinel;V. Pinel;V. Ferrazzini;P. Okubo
通讯作者：
P. Okubo
夏威夷火山观测站地震数据，2005 年 1 月至 12 月
DOI：
--
发表时间：
2006
期刊：
影响因子：
--
作者：
J. Nakata
通讯作者：
J. Nakata
影响因子：
5.2
作者：
Bell, Andrew F.;Naylor, Mark;Main, Ian G.
通讯作者：
Main, Ian G.