Geomorphic expression of rapid Holocene silicic magma reservoir growth beneath Laguna del Maule, Chile.
Geomorphic expression of rapid Holocene silicic magma reservoir growth beneath Laguna del Maule, Chile.
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DOI：
10.1126/sciadv.aat1513
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发表时间：
2018-06
期刊：
影响因子：
13.6
通讯作者：
Feigl KL
中科院分区：
文献类型：
--
作者：
Singer BS;Le Mével H;Licciardi JM;Córdova L;Tikoff B;Garibaldi N;Andersen NL;Diefenbach AK;Feigl KL
弯曲的古海岸线记录了活跃的流纹岩储集层上方10000年来由岩浆驱动的地表变形。大型流纹岩火山构成了危险，但预测喷发的过程和信号却令人费解。卫星大地测量揭示了地表膨胀的信号，表明在几座流纹岩火山下面的岩浆储集层内存在动荡。虽然地震、电法和位场方法可以阐明这些储层的当前结构和状态，但它们不能完全解决它们在地质时间尺度上的生长和演化过程。我们结合了对变形的古海岸表面的测量，火山作用和地表暴露的同位素测年，以及建模来确定产生流纹岩的岩浆储集层的增长速度。这种数值方法建立在岩浆侵入模型的基础上，该模型是为了解释当前长达十年的地表膨胀率，年膨胀率为>；20厘米。假设观测到的62m的抬升反映了几次非喷发的岩浆侵入，每一次都与过去10年的动乱相似，我们发现在全新世期间，约13km~3的岩浆在~7公里深的深度对储层进行了补给，并伴随着~9km~3的流纹岩喷发。岩浆输入的长期速率与储集层冻结和岩体形成相一致。然而，这里考虑的一组独特的观察表明，大型储集层可以通过断续的高通量岩浆注入在浅层孕育和生长。这些补给事件可能会导致快速通货膨胀，破坏冷却系统的稳定，推动流纹岩喷发，因此应该仔细监测。
A warped paleoshoreline records 10,000 years of magma-driven surface deformation above an active rhyolite-producing reservoir. Large rhyolitic volcanoes pose a hazard, yet the processes and signals foretelling an eruption are obscure. Satellite geodesy has revealed surface inflation signaling unrest within magma reservoirs underlying a few rhyolitic volcanoes. Although seismic, electrical, and potential field methods may illuminate the current configuration and state of these reservoirs, they cannot fully address the processes by which they grow and evolve on geologic time scales. We combine measurement of a deformed paleoshore surface, isotopic dating of volcanism and surface exposure, and modeling to determine the rate of growth of a rhyolite-producing magma reservoir. The numerical approach builds on a magma intrusion model developed to explain the current, decade-long, surface inflation at >20 cm/year. Assuming that the observed 62-m uplift reflects several non-eruptive intrusions of magma, each similar to the unrest over the past decade, we find that ~13 km3 of magma recharged the reservoir at a depth of ~7 km during the Holocene, accompanied by the eruption of ~9 km3 of rhyolite. The long-term rate of magma input is consistent with reservoir freezing and pluton formation. Yet, the unique set of observations considered here implies that large reservoirs can be incubated and grow at shallow depth via episodic high-flux magma injections. These replenishment episodes likely drive rapid inflation, destabilize cooling systems, propel rhyolitic eruptions, and thus should be carefully monitored.
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影响因子：
5.2
作者：
Chang, Wu-Lung;Smith, Robert B.;Puskas, Christine M.
通讯作者：
Puskas, Christine M.
影响因子：
64.8
作者：
Druitt, T. H.;Costa, F.;Scaillet, B.
通讯作者：
Scaillet, B.
影响因子：
18.3
作者：
Barboni, Melanie;Schoene, Blair
通讯作者：
Schoene, Blair
影响因子：
5.8
作者：
Degruyter, Wim;Huber, Christian;Kent, Adam J. R.
通讯作者：
Kent, Adam J. R.
影响因子：
4.9
作者：
Farina, Federico;Dini, Andrea;Westerman, David S.
通讯作者：
Westerman, David S.