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I just drove through what is presently the largest known terrestrial landslide, the Heart Mountain slide. It happened a vast 48-50 million years ago, but you can still see some traces of it today in dark colored mountain peaks in the area.
Geologists found the landslide when they discovered this mountain with a peak that was almost 300 million years older than the rest of the mountain. It happens to be a short distance from the far better known Yellowstone hot spot, which generated (in addition to over a hundred other major eruptions) one of the largest known volcanic eruptions of the past 26 million years.
Apparently, the volume of the landslide was about 2000 cubic km which is similar in volume to that eruption. It's interesting to see how many categories of disasters have prehistorical evidence for disasters far bigger than anything we've seen in human history.
Geologists found the landslide when they discovered this mountain with a peak that was almost 300 million years older than the rest of the mountain. It happens to be a short distance from the far better known Yellowstone hot spot, which generated (in addition to over a hundred other major eruptions) one of the largest known volcanic eruptions of the past 26 million years.
Apparently, the volume of the landslide was about 2000 cubic km which is similar in volume to that eruption. It's interesting to see how many categories of disasters have prehistorical evidence for disasters far bigger than anything we've seen in human history.
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Kirk to Enterprise -- beam down yeoman Rand and a six-pack.
(Score: 2) by Arik on Sunday March 07 2021, @07:17PM
Well, by human scales, even the glaciers retreat would have been slow, as you correctly worked out. Leaving plenty of time for flora and fauna of all kinds to move in as it was still in progress.
At the same time, once a landslide starts, it happens frightfully fast, even by human scale. So I see more than enough opportunity for carnage here.
"And the sea level rise was so slow"
Except that's not really so slow, when you realize that's a global average and local values behave very differently. Some spots would see very quick rises and falls. Also just a 5cm change is enough to turn a beach paradise complete with numerous easily caught sources of food into a salt marsh full of mosquitos and crocodiles.
Yes, it would have been slow enough that /most/ people could escape the worst effects, one way or another, but everyone would have been affected and many would have died prematurely, one way or another.
"and perhaps some parts of the Doggerland"
*Perhaps some parts*? Really?
Just how do you suppose *any* of it winds up beneath the north sea without being catastrophically flooded at some point?
That and the Black Sea are good examples of cases where we *know* this happened, and both were (by the standards of the day and region, at least) heavily populated areas. Even before agriculture, fertile lowlands draw larger populations, because they can support larger populations, and because hunters go where the game is.
How many actually drowned on Dogger Bank? I would suspect relatively few, there would have been a lot of time to flee from the water *in most cases* but when people retreat from water they tend to go towards the high points, and that wouldn't necessarily have been a safe direction long term. The Dogger Hills would have been filled with people and other animals retreating from the water, creating overpopulation and leading to food shortage; and eventually even those hills sink beneath it.
Did they know how to make canoes? Probably, there's a surviving example from the area that's old enough, it's a pine dugout. But did that last generation even have any pine trees left when they realized they had to leave? And even if they did have the trees, and made the canoes, by that point they would have been quite some ways from the coast. The North Sea probably was no more gentle then than now. Perhaps an intrepid traveler showed up with a boat from somewhere else, where they still had trees, and wanted to rescue them. Perhaps some told him no, they would die where their ancestors were buried instead of risking the journey. We'll never know exactly what happened, but that's likely the character of it.
"then you probably could have easily walked out of the flood zone."
If you were near the other end of the plain, and somehow *knew* that you needed to leave, then yes, doubtless.
But how would you know? At the moment the water is breaking through hundreds of miles away, there's certainly nothing to tell you this. How close does the water come before people of the time would have known to start running?