State Key Laboratory of Geological Processes and Mineral Resources, Center for Global Tectonics, School of Earth Sciences, China University of Geosciences, Wuhan, 430074, China.
Three Gorges Research Center for Geo-hazards, China University of Geosciences, Wuhan, 430074, China.
Sci Rep. 2021 Mar 22;11(1):6486. doi: 10.1038/s41598-021-86063-y.
Earthquakes are a consequence of the motions of the planet's tectonic plates, yet predicting when and where they may occur, and how to prepare remain some of the shortcomings of using scientific knowledge to protect human life. A devastating Mw 7.0 earthquake on October 30, 2020, offshore Samos Island, Greece was a consequence of the Aegean and Anatolian upper crust being pulled apart by north-south extensional stresses resulting from slab rollback, where the African plate is subducting northwards beneath Eurasia, while the slab is sinking by gravitational forces, causing it to retreat southwards. Since the retreating African slab is coupled with the overriding plate, it tears the upper plate apart as it retreats, breaking it into numerous small plates with frequent earthquakes along their boundaries. Historical earthquake swarms and deformation of the upper plate in the Aegean have been associated with massive volcanism and cataclysmic devastation, such as the Mw 7.7 Amorgos earthquake in July 1956 between the islands of Naxos and Santorini (Thera). Even more notable was the eruption of Santorini 3650 years ago, which contributed to the fall of the Minoan civilization. The Samos earthquake highlights the long historical lack of appreciation of links between deep tectonic processes and upper crustal deformation and geological hazards, and is a harbinger of future earthquakes and volcanic eruptions, establishing a basis for studies to institute better protection of infrastructure and upper plate cultures in the region.
地震是地球板块运动的结果，但预测它们何时何地可能发生以及如何做好准备，仍然是利用科学知识保护人类生命的一些不足之处。2020 年 10 月 30 日，希腊萨摩斯岛近海发生了一次毁灭性的 Mw7.0 级地震，这是由于爱琴海和安纳托利亚上层地壳被北南向伸展应力拉开的结果，这些伸展应力是由板片后退引起的，在板片后退过程中，非洲板块向北俯冲进入欧亚大陆，而板片则因重力而沉降，导致其向南后退。由于后退的非洲板块与上覆板块耦合，它在后退时撕裂了上覆板块，将其破碎成许多小板块，其边界经常发生地震。爱琴海上层板块的历史地震群和变形与大规模火山活动和灾难性破坏有关，如 1956 年 7 月纳克索斯岛和圣托里尼岛（锡拉）之间发生的 Mw7.7 级阿莫尔戈斯地震。更值得注意的是，3650 年前圣托里尼火山的爆发，导致了米诺斯文明的衰落。萨摩斯地震突出表明，长期以来一直缺乏对深部构造过程与上层地壳变形和地质灾害之间联系的认识，这是未来地震和火山爆发的先兆，为研究在该地区更好地保护基础设施和上层板块文化奠定了基础。
