Vulnerability of the Dover Strait to coseismic tsunami hazards: insights from numerical modelling

Abstract

S U M M A R YOn 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 M W = 7 have been deemed possible on intraplate fault systems in neighbouring Benelux. This study aims to determine the possibility of a M W > 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 M W = 6.9. For earthquakes with M W of 5.5, none of the fault models we tested produced a tsunami on neighbouring shores. However, for earthquakes with M W 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 tsunamirelated damage because of bathymetric forcing factors is consistently obtained.

Modeling the Potential of Tsunami Hazard in Labuan Bajo Towards A Disaster-Resilient Tourism Area

“…The simulation results from scenario 1 show that around Labuan Bajo, the maximum tsunami wave height is approximately 9 m (Figure 5). In general, along the coasts of Labuan Bajo, Tanjung Watu Asah, Rangka Bay, Boleng Bay, Terang Bay and Gili Bodo Strait it reach more than 5 m. At some specific locations, such as narrow bays and straits, where tsunami wave height amplifies, the maximum attained is 8-9 m (Patton, Wilson, Dengler, LaDuke, & Miller, 2019;Roger & Gunnell, 2012;UNESCO-IOC, 2007). This happened in small bays north of Labuan Bajo City, Rangka Bay, Teluk Terang and in the Gili Bodo Strait.…”

The Fukushima Disaster and Japan’s Nuclear Plant Vulnerability in Comparative Perspective

“…The primary sources of historical tsunami data are the National Geophysical Data Center (NGDC) Global Historical Tsunami Database and the Russian Academy of Sciences (RAS) Novosibirsk Tsunami Laboratory Historical Tsunami Database. Where possible, relevant government and academic reports were also consulted for confirmation. − We use all historical data available on past events. Several caveats about this data should be recognized: Historical data is more readily available for certain geographical regions.…”