Etna active volcano is characterized by different types of phenomenology and the related hazards including lava flows from central and fissural vents, ash dispersion, seaward sliding, surface faulting, and earthquakes. The cross-correlation among these types of hazard are not well understood. On 24-27 December 2018 an eruption from aligned vents located on the summit of the volcano occurred. It was followed by damaging earthquakes with magnitude up to 4.8. The more energetic event was shallow（1 km depth） and occurred on 26 December on a well-known fault delimiting the southern sliding flank of the volcano, near the coast. Monitoring data show that the main hazards of the December 2018 eruption were related to ash emissions and earthquakes. The eruption focused on a 3000 m long, 3 m wide dike that released about 1011 J/m; the emitted lava flows invaded an area free of infrastructures and people. On the contrary the M =4.8 earthquake occurred in a densely populated area and severe damages were recorded. These latter were due to both seismic shaking and opening of fractures along a preexisting fault. Both the eruption and earthquake were recorded by satellite data and a link is proposed. The eruptive fracture, which affected a sector of the volcano where the probability of eruptive fissure opening was estimated elevated, produced a positive stress change in the fault area where the earthquake occurred. Therefore, the earthquake was triggered by magma intrusion along a dike.
类型: 国际会议
作者: Guido VENTURA
来源: 第九届世界华人地质科学研讨会 2019-06-01
年度: 2019
分类: 基础科学
专业: 地质学,地质学,地球物理学,地球物理学
单位: INGV
分类号: P317;P315
DOI: 10.26914/c.cnkihy.2019.028290
页码: 32
总页数: 1
文件大小: 55k
下载量: 2
本文来源: https://www.lunwen90.cn/article/1f61d091f8f4b41651f10b69.html