Top–Down Precursory Volcanic Seismicity: Implications for ‘Stealth’ Magma Ascent and Long-Term Eruption Forecasting
Top–Down Precursory Volcanic Seismicity: Implications for ‘Stealth’ Magma Ascent and Long-Term Eruption Forecasting
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自上而下的前兆火山地震活动：对“隐形”岩浆上升和长期喷发预测的影响
DOI：
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发表时间：
2018
影响因子：
2.9
通讯作者：
K. Cashman
中科院分区：
文献类型：
--
作者：
D. Roman;K. Cashman
当形成连接地壳岩浆库和地球表面的管道时，就会发生火山喷发。通常认为管道形成是一个“自下而上”的过程，也是前兆火山地震活动的主要驱动因素，而火山地震活动是全世界火山最常监测的参数。如果这两个假设都成立，则初始前兆地震活动在空间上应与岩石学估计的岩浆储层深度一致。对数十年静止间隔后喷发的火山的严格约束案例研究的回顾表明，相反，最初的前兆地震活动始终比岩浆库浅几公里。我们提出了一个涉及动荡和爆发的三个阶段过程的模型。最初的管道形成发生在“分阶段”阶段，要么是抗震阶段，要么是在喷发前兆发生之前很久。分期可能涉及缓慢的上升速度和/或较小的体积。然后，不稳定阶段与前兆地震活动的开始同时发生，导致喷发阶段。该模型意味着，最关键的是，通过连续监测中浅地壳的应力状态，有可能在地震活动发生之前就探测到前驱岩浆的上升。
Volcanic eruptions occur when a conduit forms to connect a crustal magma reservoir to Earth’s surface. Conduit formation is generally assumed to be a ‘bottom-up’ process and a major driver of precursory volcanic seismicity, which is the most commonly monitored parameter at volcanoes worldwide. If both assumptions are true, initial precursory seismicity should coincide spatially with petrologically-estimated magma reservoir depths. A review of well-constrained case studies of volcanoes that erupt after repose intervals of decades indicates that, to the contrary, initial precursory seismicity is consistently several kilometers shallower than the magma reservoir. We propose a model involving a three-phase process of unrest and eruption. Initial conduit formation occurs during a ‘staging’ phase, either aseismically or long before the onset of the immediate precursory run-up to eruption. Staging may involve slow ascent rates and/or small volumes. A destabilization phase then coincides with the onset of precursory seismicity, leading to an eruption phase. This model implies that, most critically, it may be possible to detect precursory magma ascent well before the onset of seismic activity by continuous monitoring of the state of stress in the mid to shallow crust.
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鲁阿佩胡火山岩浆过程的扩散计时及其与监测数据的比较
影响因子：
2.9
作者：
Kilgour G
通讯作者：
Kilgour G
影响因子：
18.3
作者：
M. Stock;M. Humphreys;V. Smith;R. Isaia;D. Pyle
通讯作者：
M. Stock;M. Humphreys;V. Smith;R. Isaia;D. Pyle
影响因子：
18.3
作者：
M. Parks;J. Biggs;P. England;T. Mather;P. Nomikou;Kirill Palamartchouk;X. Papanikolaou;D. Paradissis;B. Parsons;D. Pyle;Costas Raptakis;V. Zacharis
通讯作者：
M. Parks;J. Biggs;P. England;T. Mather;P. Nomikou;Kirill Palamartchouk;X. Papanikolaou;D. Paradissis;B. Parsons;D. Pyle;Costas Raptakis;V. Zacharis
影响因子：
18.3
作者：
Caricchi, Luca;Annen, Catherine;Pinel, Virginie
通讯作者：
Pinel, Virginie