Cannavò Flavio, Nunnari Giuseppe
Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, Catania, 95123, Italy.
University of Catania, Dipartimento di Ingegneria Elettrica, Elettronica ed Informatica, Catania, 95125, Italy.
Sci Rep. 2016 Mar 1;6:22289. doi: 10.1038/srep22289.
Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour.
火山构成了具有多个自由度的耗散系统。它们的喷发是涉及相互作用的化学 - 物理系统的复杂过程的结果。目前，由于所涉及现象的复杂性以及缺乏精确测量，解析模型和数值模型都无法同时纳入喷发所涉及的主要过程，因此火山动力学的预测相当不可靠。另一方面，对一些喷发参数（如持续时间）的准确预测可能是自然灾害评估和缓解的关键因素。通过分析包含几乎所有已知火山喷发的大型数据库，我们确定喷发持续时间似乎由一种描述喷发持续时间动态的通用分布来表征。特别是，本文提出了一种合理的全球火山喷发持续时间幂律分布，该分布在全球不同火山环境中均适用。我们还引入了一种新的、简单且现实的管道模型，它可以遵循相同的经验分布。由于所提出的模型属于自组织系统家族，它可能支持这样的假设，即简单机制可以自然地导致火山行为中出现的复杂性。
