Massive collapse of volcano edifices triggered by hydrothermal pressurization
Massive collapse of volcano edifices triggered by hydrothermal pressurization
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热液加压引发火山建筑物大规模倒塌
DOI：
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发表时间：
2004
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影响因子：
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通讯作者：
M. Reid
中科院分区：
文献类型：
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作者：
M. Reid
陡峭火山侧翼的灾难性坍塌威胁着世界各地层状火山的生命。尽管破坏稳定的浅层岩浆侵入建筑物伴随着一些坍塌(例如圣海伦斯火山)，但另一些坍塌发生时没有喷发年轻的岩浆物质(例如万代)。后一种崩溃可能很难预料到。没有岩浆喷发的历史性崩塌与崩塌时的浅层热液地下水系统有关。通过使用热流和地下水流动的数值模型，我评估了热液驱动的坍塌的效果。来自深部偏远岩浆侵入的加热会产生暂时升高的孔隙流体压力，并向上传播到建筑物中。有效应力变形模型表明，这些压力能够破坏建筑物核心的稳定，导致大规模的深层坍塌。远场加压只发生在特定的岩石水力性质；然而，来自许多热液系统的数据表明，这一过程可以在现实环境中进行。
Catastrophic collapse of steep volcano flanks threatens lives at stratovolcanoes around the world. Although destabilizing shallow intrusion of magma into the edifice accompanies some collapses (e.g., Mount St. Helens), others have occurred without eruption of juvenile magmatic materials (e.g., Bandai). These latter collapses can be difficult to anticipate. Historic collapses without magmatic eruption are associated with shallow hydrothermal groundwater systems at the time of collapse. Through the use of numerical models of heat and groundwater flow, I evaluate the efficacy of hydrothermally driven collapse. Heating from remote magma intrusion at depth can generate temporarily elevated pore-fluid pressures that propagate upward into an edifice. Effective-stress deformation modeling shows that these pressures are capable of destabilizing the core of an edifice, resulting in massive, deep-seated collapse. Far-field pressurization only occurs with specific rock hydraulic properties; however, data from numerous hydrothermal systems illustrate that this process can transpire in realistic settings.