科研之友
微信
新浪微博
Facebook
分享链接
摘要
On 1580 April 6, a large earthquake shook the eastern English Channel and its shores, with numerous casualties and significant destruction documented. Some reports suggest that it was followed by a tsunami. Meanwhile, earthquake magnitudes of MW= 7 have been deemed possible on intraplate fault systems in neighbouring Benelux. This study aims to determine the possibility of a MW > 5.5 magnitude earthquake generating a tsunami in the Dover Strait, one of the world's busiest seaways. In a series of numerical models focusing on sensitivity analysis, earthquake source parameters for the Dover Strait are constrained by palaeoseismological evidence and historical accounts, producing maps of wave heights and analysis of frequencies based on six strategically located virtual tide gauges. Of potential concern to engineering geologists, a maximum credible scenario is also tested for MW= 6.9. For earthquakes with MW of 5.5, none of the fault models we tested produced a tsunami on neighbouring shores. However, for earthquakes with MW 6.9, both extensional and thrusting events produced tsunami waves with open-water amplitudes of up to 1.5 m, and higher amplitudes might be expected in regions where waves are amplified by regional nearshore bathymetry. Sensitivity to parameter choice is emphasized but a pattern of densely inhabited coastal hotspots liable to tsunami-related damage because of bathymetric forcing factors is consistently obtained.
- 出版日期2012-2
