Extreme rainfall triggered the 2018 rift eruption at Kilauea Volcano
Extreme rainfall triggered the 2018 rift eruption at Kilauea Volcano
复制标题
DOI：
10.1038/s41586-020-2172-5
复制
发表时间：
2020-04-01
期刊：
影响因子：
64.8
通讯作者：
Amelung, Falk
中科院分区：
文献类型：
--
作者：
Farquharson, Jamie I.;Amelung, Falk
2018年5月夏威夷基拉韦厄火山的裂谷侵入和喷发是其至少200年来最不寻常的喷发序列之一，但触发机制仍然难以捉摸(1)。在此之前，发生了几个月的异常高降雨量。有人提出，降雨可以调节浅层火山活动(2，3)，但目前尚不清楚它是否会对与岩浆运输相关的更深处产生影响。在这里，我们展示了在喷发之前和喷发期间，降雨渗入基拉韦厄火山地下，使1至3公里深处的孔压增加了0.1至1千帕斯卡，达到近50年来的最高压力。我们认为，裂谷带内孔隙压力的变化导致了建筑物的弱化和力学破坏，促使机会性的堤坝入侵，最终促进了喷发。降水引起的喷发触发与没有前兆峰顶膨胀是一致的，表明这次侵入--与其他不同--不是由新岩浆强行侵入裂谷地带引起的。此外，对历史喷发发生的统计分析表明，降雨模式对基拉韦厄火山喷发和侵入的时间和频率有很大影响。因此，火山活动可以通过引发建筑物岩石破坏的极端降雨来调节--这是评估火山灾害时应该考虑的一个因素。值得注意的是，与持续的人为气候变化相关的日益极端的天气模式可能会增加世界各地由降雨引发的火山现象的可能性。就在2018年5月Lauea火山KI&X304喷发之前和喷发期间，异常高的降雨量将地下孔压增加到50年来的最高水平，导致建筑物弱化和机械故障。
The May 2018 rift intrusion and eruption of Kilauea Volcano, Hawai'i, represented one of its most extraordinary eruptive sequences in at least 200 years, yet the trigger mechanism remains elusive(1). The event was preceded by several months of anomalously high precipitation. It has been proposed that rainfall can modulate shallow volcanic activity(2,3), but it remains unknown whether it can have impacts at the greater depths associated with magma transport. Here we show that immediately before and during the eruption, infiltration of rainfall into Kilauea Volcano's subsurface increased pore pressure at depths of 1 to 3 kilometres by 0.1 to 1 kilopascals, to its highest pressure in almost 50 years. We propose that weakening and mechanical failure of the edifice was driven by changes in pore pressure within the rift zone, prompting opportunistic dyke intrusion and ultimately facilitating the eruption. A precipitation-induced eruption trigger is consistent with the lack of precursory summit inflation, showing that this intrusion-unlike others-was not caused by the forceful intrusion of new magma into the rift zone. Moreover, statistical analysis of historic eruption occurrence suggests that rainfall patterns contribute substantially to the timing and frequency of Kilauea's eruptions and intrusions. Thus, volcanic activity can be modulated by extreme rainfall triggering edifice rock failure-a factor that should be considered when assessing volcanic hazards. Notably, the increasingly extreme weather patterns associated with ongoing anthropogenic climate change could increase the potential for rainfall-triggered volcanic phenomena worldwide.Immediately before and during the eruption of Ki & x304;lauea Volcano in May 2018, anomalously high rainfall increased the pore pressure in the subsurface to its highest level in 50 years, causing weakening and mechanical failure of the edifice.