Magma reservoir response to transient recharge events: The case of Santorini volcano (Greece)
Magma reservoir response to transient recharge events: The case of Santorini volcano (Greece)
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DOI：
10.1130/g37333.1
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发表时间：
2016-01-01
期刊：
影响因子：
5.8
通讯作者：
Kent, Adam J. R.
中科院分区：
文献类型：
--
作者：
Degruyter, Wim;Huber, Christian;Kent, Adam J. R.
火成岩体是由不同速率和持续时间的幕式岩浆注入事件逐渐形成的。这样的补给事件既可以形成上地壳岩浆库，也可以引发火山喷发。这种行为上的分歧仍然没有得到很好的约束，但对火山危害评估至关重要。在这里，我们使用了一个数值模型，该模型结合了岩浆库中的热过程和力学过程来研究圣托里尼（希腊）岩浆系统在过去20ky的演化。我们的结果限制了在已知的10(-3)km(3)/年的长期平均流入速率下触发喷发所需的补给速率和持续时间。燃烧室的大小及其释放的挥发性物质含量是对触发喷发的临界补给速率和持续时间的主要控制因素。我们的模型成功地再现了米诺斯火山喷发和Nea Kameni活动的主要特征，为当前次火山储层的活动部分提供了体积估计，以及有关溶解挥发物存在的信息。热力学模型提供了一个新的框架，将历史喷发记录与大地测量相结合，并为了解活火山中心的过去、现在和未来提供了一个背景。
Igneous bodies are built incrementally by episodic magma injection events that vary in rate and duration. Such recharge events can either grow an upper crustal magma reservoir or trigger an eruption. This bifurcation in behavior remains poorly constrained but is essential to volcanic hazard assessment. Here we use a numerical model that couples the thermal and mechanical processes in a magma reservoir to study the evolution of the Santorini magmatic system (Greece) over the past 20 k.y. Our results constrain the recharge rate and duration that are necessary to trigger an eruption for the known long-term average inflow rate of 10(-3) km(3)/yr. The size of the chamber and its exsolved volatile content are dominant controls on the critical recharge rate and duration that will trigger an eruption. Our model successfully reproduces the main features of the Minoan eruption and Nea Kameni activity, providing volume estimates for the active part of the current subvolcanic reservoir as well as information regarding the presence of exsolved volatiles. Thermomechanical models offer a new framework to integrate the historic eruption record with geodetic measurements and provide a context to understand the past, present, and future of active volcanic centers.