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A gigantic landslide shows the limit to how high mountains can grow

economist.com

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Re: A gigantic landslide shows the limit to how high mountains can grow

#21

Post by dylan604 »

kennyadam wrote: post #18
gumby wrote: post #13

Earlier quoted context omitted.

> … the energy released would have been equivalent to around six times that of the Tsar Bomba But how does that compare to an Olympic swimming pool full of double decker omnibuses being dropped from the same height?

The lengths people will go to to avoid using the metric system!

They go in increments of 50m. If you asked the width people go to, it would be 25m.

So your comment about avoiding the metric system is not really accurate. We don't say the Earth is approximately equal to 150 million kilometres from the Sun, we say one AU. We just use numbers that can be comprehended.

Re: A gigantic landslide shows the limit to how high mountains can grow

#22

Post by sjkoelle »

mjb wrote: post #14
mjb wrote: post #12

For comparison, this is between 4 and 5 times larger than the Osceola Mudflow ( https://en.wikipedia.org/wiki/Osceola_Mudflow ) that formed the 550km² of fertile plains around the south end of Puget Sound (near Seattle) and knocked a huge chunk out of Mount Rainier. If you drive from Auburn to Enumclaw, for example, notice how flat the land is and think about how that was hilly Cascade foothills and glaciated drumlin…

Related, there's a cool transition if you hike up the Greenwater river (starting at the town of Greenwater, heading towards FS70) there's a cool transition where the geology switches from Osceola mud to the more typical Cascade foothill geology (about half a mile from the White river).

its a real geologic zoo around there

Re: A gigantic landslide shows the limit to how high mountains can grow

#23

Post by Jun8 »

I think the title is off: the theoretical limit of how high a mountain can be on a rocky planet of given size can be found by physical considerations. The geological and other factors come into play, too to make the practical limit much smaller than the theoretical one.

Re: A gigantic landslide shows the limit to how high mountains can grow

#24

Post by vkou »

kennyadam wrote: post #18
gumby wrote: post #13

Earlier quoted context omitted.

> … the energy released would have been equivalent to around six times that of the Tsar Bomba But how does that compare to an Olympic swimming pool full of double decker omnibuses being dropped from the same height?

The lengths people will go to to avoid using the metric system!

I think most people can understand what a meter is, or what a kilometer is, but would have no idea of what a kilojoule is, or what the energy inside a barrel of oil is.

Re: A gigantic landslide shows the limit to how high mountains can grow

#25

Post by JamesLeonis »

> Examining the surrounding cliffs for signs of a collapse, he noticed that a peak known as Annapurna IV offered a relatively smooth, steep face which seemed to fit.

I was interested in what the mountain looked like, and found a whole page dedicated to it [0]. In the picture of the west side you can see the steep face. The altitude map also has an unusually large flat area to the west of the mountain.

[0]: https://nepalhimalpeakprofile.org/annapurna-iv

Re: A gigantic landslide shows the limit to how high mountains can grow

#26

Post by masklinn »

mjb wrote: post #12

For comparison, this is between 4 and 5 times larger than the Osceola Mudflow ( https://en.wikipedia.org/wiki/Osceola_Mudflow ) that formed the 550km² of fertile plains around the south end of Puget Sound (near Seattle) and knocked a huge chunk out of Mount Rainier. If you drive from Auburn to Enumclaw, for example, notice how flat the land is and think about how that was hilly Cascade foothills and glaciated drumlin…

> According to my father, until around the time he was doing Geology at university (late 1960s), the consensus was that these kinds of events (and mass wasting more generally) were geologic processes that no longer happened (and hadn't really happened throughout the Holocene). I don't know the history in detail there, but it does seem true that only relatively recently we've had a real appreciation for how active Earth's geology still is.

I can’t fathom how we could think that, surely as long as plates move around and stone weathers this sort of geological events can happen?

They’re certainly not common on historical timescales, so the odds you’d find yourself sharing time (let alone space) with one are low, but what would have made them stop?

Re: A gigantic landslide shows the limit to how high mountains can grow

#27

Post by yard2010 »

akiselev wrote: post #4

Before anyone gets excited, the landslide occurred in the 12th century or so :( I was all excited to plan a rock hounding trip to the Himalayas. I even sent out the Sherpa bat signal (it’s a silhouette of me shaving a Himalayan yak), only to find out I’m eight hundred years too late.

Some people like the idea of looking into the future, but I would prefer going back in time as a passenger only to see.. I mean we're time traveling any instant, just wait enough and you get to time travel, but there are some events like 100-200 years ago you can't ever really experience..

Re: A gigantic landslide shows the limit to how high mountains can grow

#28

Post by swamp40 »

masklinn wrote: post #26
mjb wrote: post #12

For comparison, this is between 4 and 5 times larger than the Osceola Mudflow ( https://en.wikipedia.org/wiki/Osceola_Mudflow ) that formed the 550km² of fertile plains around the south end of Puget Sound (near Seattle) and knocked a huge chunk out of Mount Rainier. If you drive from Auburn to Enumclaw, for example, notice how flat the land is and think about how that was hilly Cascade foothills and glaciated drumlin…

> According to my father, until around the time he was doing Geology at university (late 1960s), the consensus was that these kinds of events (and mass wasting more generally) were geologic processes that no longer happened (and hadn't really happened throughout the Holocene). I don't know the history in detail there, but it does seem true that only relatively recently we've had a real appreciation for how active Ear…

They would mostly stop because now the Earth is nicely round. Most of the original bumpiness created during Earth's creation has been smoothed out. That's probably what he meant.

Re: A gigantic landslide shows the limit to how high mountains can grow

#29

Post by yk »

kennyadam wrote: post #18
gumby wrote: post #13

Earlier quoted context omitted.

> … the energy released would have been equivalent to around six times that of the Tsar Bomba But how does that compare to an Olympic swimming pool full of double decker omnibuses being dropped from the same height?

The lengths people will go to to avoid using the metric system!

double-decker buses are clearly imperial units.

Re: A gigantic landslide shows the limit to how high mountains can grow

#30

Post by geostupid »

sjkoelle wrote: post #22
mjb wrote: post #14

Earlier quoted context omitted.

Related, there's a cool transition if you hike up the Greenwater river (starting at the town of Greenwater, heading towards FS70) there's a cool transition where the geology switches from Osceola mud to the more typical Cascade foothill geology (about half a mile from the White river).

its a real geologic zoo around there

Love the geologic zoo!

I refer to botanical gardens as 'botanical zoos' as well

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