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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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squatcho, n.:
The button at the top of a baseball cap.
-- "Sniglets", Rich Hall & Friends
(Score: 2) by Arik on Sunday March 07 2021, @09:36PM
I would think that it doesn't really matter how slowly it floods, if it's an island that becomes a sea mount, it undergoes catastrophic flooding.
"And that's pretty much that."
Not really. Just because someone in the area could make a canoe, doesn't mean anyone on the disappearing island could do so; and remember we're talking about a small, crude, dugout canoe at best. In open water, very very cold open water.
"I doubt there would be any such local effects unless a basin like the Black Sea were being filled in."
NOAA gives a 40cm spread for local effects currently. https://oceanservice.noaa.gov/facts/globalsl.html (the graphic at top)
Granted, the negative measures seem to be concentrated in deep sea areas. Why? I'm not sure, so I'll assume that this is inherent and not accidental so as to very careful not to overestimate; giving more like a 20cm variance in shorelines. That's still considerably more than your 5cm/year estimate. Notice that red hotspot in the Baltic Sea? That's where glacier fed rivers feed into the sea. The Black Sea is also fed by snowcapped mountains and also shows a nice red spot.
Lots of yellow and red near the poles, where glacier meltoff is entering the ocean. A huge red patch centered around Indonesia, the Philippines, Papua, Micronesia, Melanesia - areas with heavy rainfall. The shoreline varies up to 20cm higher than the global average sea level as a result of these sorts of inputs currently.
At the height of the meltoff the local differences would not have been any /less/ dramatic than they are now. They would develop quickly, and then fade slowly as the global average increased more slowly.