Viscosity of high-K basalt from the 5th April 2003 Stromboli paroxysmal explosion
Viscosity of high-K basalt from the 5th April 2003 Stromboli paroxysmal explosion
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2003 年 4 月 5 日斯特龙博利火山爆发的高 K 玄武岩的粘度
DOI：
10.1016/j.chemgeo.2008.12.023
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发表时间：
2009
期刊：
影响因子：
3.9
通讯作者：
D. Dingwell
中科院分区：
文献类型：
--
作者：
V. Misiti;F. Vetere;A. Mangiacapra;H. Behrens;A. Cavallo;P. Scarlato;D. Dingwell
2003年4月5日的突发事件是斯特龙博利近50年来发生的最强烈的爆炸。这一事件只持续了几分钟，其特征是两次剧烈的爆炸，随后是气体和火山碎屑的排放。为了约束模型的动力学的突发事件的粘度无水和含水Stromboli高钾（HK）玄武岩熔体已被测量。粘度已被调查在低粘度范围内的落球法在超液相线温度（1423至1673 K）和0.5 GPa和在高粘度范围内的玻璃化转变温度（723至1035 K）附近的微渗透在大气压下。落球实验在活塞缸装置中进行，其中熔体的水含量从标称无水（0.02重量%）变化至标称无水（0.01重量%）。H2O）至4.16重量%水高粘度和低粘度数据的组合允许作为温度和水contentusing修改的Tamman-Vogel-Fulcher方程的函数的粘度的一般描述。使用这些新的粘度数据，估计的流动状态和岩浆速度。我们的数据表明，岩浆从7-8公里深的储层上升到约3公里深的较浅储层，可能在几分钟内发生。此外，我们推断湍流状态。最后，我们对上升速度的估计与岩石学研究的结果定性一致（例如[Bertagnini，A.，Métrich，N.，Landi，P.，Rosi，M.，2003.斯特龙博利火山（意大利伊奥利亚群岛）：一个稳态玄武岩火山深层补给系统的开放窗口。Journal of Geophysical Research 108，2336-2350.]），这表明湍流状态和快速上升速度，从而抑制挥发物损失诱导的结晶。我们的结论是，在斯特龙博利岛的危险评估应包括非常迅速上升的可能性，从深度较少演变的熔体。
The 5th April 2003 paroxysmal event was the strongest explosion that has occurred at Stromboli in the last 50 years. This event lasted only few minutes and was characterised by two violent explosions, followed by gas and pyroclast emission. In order to constrain models of the dynamics of the paroxystic event the viscosity of anhydrous and hydrous Stromboli high potassium (HK)-basaltic melts have been measured. Viscosity has been investigated in the low viscosity range with the falling sphere method at superliquidus temperatures (1423 to 1673 K) and 0.5 GPa and in the high viscosity range with micropenetration near the glass transition temperature (723 to 1035 K) at atmospheric pressure. Falling sphere experiments were performed in a piston cylinder apparatus with melts whose water content varies from nominally anhydrous (0.02 wt.% H2O) to 4.16 wt.% H2O. The combination of high- and low-viscosity data permits a general description of the viscosity as a function of temperature and water contentusing a modified Tamman–Vogel–Fulcher equation. Using these new viscosity data, an estimation of the flow regime and magma velocity is performed. Our data suggest that the ascent of magma from the 7–8 km deep reservoir to a shallower reservoir located at about 3 km of depth, may occur within minutes. Moreover, we infer a turbulent flow regime. Finally, our estimates of the ascent velocity agree qualitatively with results from petrological studies (e.g. [Bertagnini, A., Métrich, N., Landi, P., Rosi, M., 2003. Stromboli volcano (Aeolian Archipelago, Italy): an open window on the deep-feeding system of a steady state basaltic volcano. Journal of Geophysical Research 108, 2336–2350.]), which indicate a turbulent flow regime and rapid ascent velocities such to inhibit volatile-loss-induced crystallization. We conclude that hazard evaluation at Stromboli Island should incorporate the likelihood of very rapid ascent of less-evolved melts from depth.