How an explosive-filled shipwreck in the Thames could trigger a tsunami

It’s a sultry June day on the glistening Thames Estuary; perfect for a river cruise and a spot of lunch in Kent. Yet there’s something vaguely unsettling in the distance as we embark the “Cruiser” tourist boat at the end of Southend pier; gentle waves are lapping at three masts of a wrecked ship, a phalanx of buoys warning people off coming too close.