Dipartimento di Scienze della Terra, Università di Firenze, Firenze 50121, Italy.
Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, Firenze 50121, Italy.
Nat Commun. 2015 May 18;6:6998. doi: 10.1038/ncomms7998.
Effusive eruptions are explained as the mechanism by which volcanoes restore the equilibrium perturbed by magma rising in a chamber deep in the crust. Seismic, ground deformation and topographic measurements are compared with effusion rate during the 2007 Stromboli eruption, drawing an eruptive scenario that shifts our attention from the interior of the crust to the surface. The eruption is modelled as a gravity-driven drainage of magma stored in the volcanic edifice with a minor contribution of magma supplied at a steady rate from a deep reservoir. Here we show that the discharge rate can be predicted by the contraction of the volcano edifice and that the very-long-period seismicity migrates downwards, tracking the residual volume of magma in the shallow reservoir. Gravity-driven magma discharge dynamics explain the initially high discharge rates observed during eruptive crises and greatly influence our ability to predict the evolution of effusive eruptions.
溢流式喷发的机制可以解释为，当岩浆在深部地壳中的岩浆房上升时，火山会恢复平衡。在 2007 年斯特龙博利火山喷发期间，将地震、地面变形和地形测量数据与喷发率进行了比较，得出了一个喷发情景，这一情景将我们的注意力从地壳内部转移到了表面。该喷发被模拟为一个受重力驱动的过程，将储存在火山中的岩浆排出，同时少量的岩浆以稳定的速率从深部储层供应。在这里，我们表明，排放率可以通过火山的收缩来预测，而且甚长周期地震活动向下迁移，跟踪浅层储层中剩余的岩浆体积。重力驱动的岩浆排放动力学解释了在喷发危机期间观测到的最初高排放率，并极大地影响了我们预测溢式喷发演化的能力。
