由进入海洋的火山爆发造成的快速和破坏性的密度流
Michael A Clare1, Isobel A Yeo1, Sally Watson2
1National Oceanography Centre, Southampton, UK.
概括
火山喷发直接进入海洋可以产生极快的海底电流,超过122公里/小时. 这些强大的水下流比其他自然灾害更快,
科学领域:
- 海洋地质学和火山学
- 海洋学和自然危险
背景情况:
- 陆地火山爆发会产生可引发海的火流.
- 直接落入海洋的火山物质的行为和影响仍未得到充分记录.
- 之前的研究还没有研究海底火山喷发产生的海底流.
研究的目的:
- 记录和分析由火山直接进入海洋而产生的海底流的特征.
- 将这些火山密度流与其他地质事件的速度和影响进行比较.
- 提供大规模海底火山爆发的证据.
主要方法:
- 分析火山爆发后的海底数据.
- 测量火山密度流的流速和流出距离.
- 挖掘出来的岩石与已知的火山周围的地质特征进行比较.
主要成果:
- 火山物质在的水下坡道上迅速堆积,引发极快的海底流 (122公里/小时).
- 这些电流表现出很长的流出距离 (>100公里),并且比地震,洪水或风暴产生的电流更快.
- 造成海底电缆断裂和深度挖掘的严重破坏.
结论:
- 直接进入海洋的火山可以产生强大而破坏性的海底密度流.
- 这些火山流构成重大危险,
- 观测到的扫提供了全球其他水下火山现场类似的大规模火山事件的证据.
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