A while back there was a volcano acting up and a few seismologists pointed out that it would be improbable but there was some chance it could explode or trigger a underwater landslide that could cause a tidal wave. A big problem for populations down the coast as it could scour the coast for hundreds of miles around the basin.

I don't want to be alarmist, and this might not apply in this case, but it is something that bears watching.