It's seems it's not this event, but I remember watching a documentary about a fishing boat (commercial) in an Alaskan lake, where they watched the rockfall descend and cause a tsunami, which lifted their boat up, over the mountainside and deposited it into a different lake on the other side of the mountain.

Even after decades had passed you could see the sheer terror and awe of how they survived.

Edit: still cannot find the reference. But the Canary Islands are poised to wipe out southern England - a sizeable chunk of the NE facing island is ready to fall and would send a tsunami undimmed onto England / France.