Researchers in Switzerland have found evidence to support the so-called “Tauredunum Event”, which is believed to have happened in AD 563 and involved a lake tsunami engulfing the shores of the Lake Léman. What’s worse is that these scientists, who published their findings in Nature Geoscience, believe that there chances that this event will happen again.
The event was described at the time by a French bishop, Gregory of Tours; in order to find more about it, the researchers analyzed the sediment composition of the lake. They found an unusual pile of sediment that appear to have been deposited there in one single event happened between AD 381 and AD 612.
The tsunami could have been caused by a combination of rockfall and the particular conditions of the lake.
“Our numerical simulations with a shallow water model show that delta collapse in the lake generates a large tsunami at various locations along the shore, where a wave of 13 metres (42 feet) is observed after only 15 minutes, and at Geneva where a wave of eight metres (26 feet) arrives 70 minutes after the mass movement is initiated,” the researchers write in their letter.
“Our study highlights that not only cities located on sea coasts and fjords are at risk from destructive tsunamis, but so are densely-populated lake shores,” they say.
Photo: Wikimedia Commons
Kremer, K., Simpson, G., & Girardclos, S. (2012). Giant Lake Geneva tsunami in AD 563 Nature Geoscience DOI: 10.1038/ngeo1618