Pering T D, McGonigle A J S, James M R, Tamburello G, Aiuppa A, Delle Donne D, Ripepe M
Department of Geography University of Sheffield Sheffield UK.
Department of Geography University of Sheffield Sheffield UK; Sezione di Palermo Istituto Nazionale di Geofisica e Vulcanologia Palermo Italy.
Geophys Res Lett. 2016 May 28;43(10):5009-5016. doi: 10.1002/2016GL069001.
Recent gas flux measurements have shown that Strombolian explosions are often followed by periods of elevated flux, or "gas codas," with durations of order a minute. Here we present UV camera data from 200 events recorded at Stromboli volcano to constrain the nature of these codas for the first time, providing estimates for combined explosion plus coda SO masses of ≈18-225 kg. Numerical simulations of gas slug ascent show that substantial proportions of the initial gas mass can be distributed into a train of "daughter bubbles" released from the base of the slug, which we suggest, generate the codas, on bursting at the surface. This process could also cause transitioning of slugs into cap bubbles, significantly reducing explosivity. This study is the first attempt to combine high temporal resolution gas flux data with numerical simulations of conduit gas flow to investigate volcanic degassing dynamics.
最近的气体通量测量结果表明，斯特龙博利式火山喷发之后常常会出现通量升高的时期，即“气体尾声”，持续时间约为一分钟。在此，我们展示了在斯特龙博利火山记录的200次事件的紫外线相机数据，首次对这些尾声的性质进行了限制，给出了爆炸加尾声阶段二氧化硫质量约为18 - 225千克的估计值。气柱上升的数值模拟表明，初始气体质量的很大一部分可被分散到从气柱底部释放出的一系列“子气泡”中，我们认为这些子气泡在到达地表破裂时会产生尾声。这个过程也可能导致气柱转变为帽状气泡，显著降低爆炸强度。本研究首次尝试将高时间分辨率的气体通量数据与管道内气体流动的数值模拟相结合，以研究火山排气动力学。
