Lots more landslide caused tsunamis, including a man-made one at Vajont Dam in Italy in 1963, which killed almost 2000 people, one that many of us watched on TV: Spirit Lake was mostly filled by the (sideways) eruption of Mount St. Helens. The man-made one? . There have been small ice-slide (from glaciers) and landslide tsunamis in Alaska. The one which has caused the most concern was at Lituya Bay, Alaska in 1958. That has led to investigations of potential landslides on volcanic islands in Hawaii, Alaska and elsewhere. There is evidence for megatsunamis in geologic time, created by these--and also by meteor strikes. (The Chicxulub crater in Yucatán) The Wikipedia article for more detail:
https://en.wikipedia.org/wiki/Megatsunami
One thing to be careful about though, there is a huge difference between a scientific debate, and a risk to large numbers of human lives. A case in point is Cumbre Vieja Volcano on La Palma in the Canary Islands. Could a major landslide there cause a megatsunami which would reach most of the US East Coast? Sure, but extremely unlikely anytime soon. Could a much smaller tsunami in the Canaries (or elsewhere for that matter) cause a major loss of life, including yours? Much, much higher probability. As long as the monitoring equipment stays in good condition, and you know what to do in a tsunami, the risk is small.
Since it can't be said often enough, if you are near the ocean, or any large body of water, and the water level starts to drop significantly, start walking up the beach, or uphill, whichever applies. (If you have young children? Teach them. Yell once to get their attention, but if they don't follow you, don't you follow them toward the ocean. They might be lucky, and figure out that you are not kidding, or they might have a floatation device.) If you are in a car, you will have to work out the right thing to do, minute by minute. Heading downhill, or sitting in traffic are very poor choices. After the tsunami, you can provide first aid, and do other good things. But while the disaster is unfolding the most you can hope to do is help yourself and/or get out of others way. (Am I a nasty person? No! Voting with your feet, and possibly with a gesture or one or two word yell, will save more lives than anything else you could be doing. If you can carry someone, or help support them? Go ahead. But you certainly don't want to be walking--or running--the wrong way on the beach and blocking others. Later there may be opportunities for heroics. Don't believe me? Look carefully at the footage of recent tsunamis on the web if you have a strong enough stomach.)
