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by wcoenen 3041 days ago
The article mentions that the himalayas grow by about 1cm per year, and that it has been growing for millions of years. Wikipedia says it is more like 5mm/year.

So I'm assuming a growth rate of 5km/My, while Everest is only about 9km.

I understand what has been limiting height: gravity, rock strength, erosion, sinking into the mantle... But since there is growth now, obviously these processes are not in short term equilibrium. So how does this play out? Are there apocalyptic landslides every million years or so? Or just periods of growth alternated with periods of shrinking?

3 comments

Punctuated equilibrium[1] — growth followed by sudden collapse — could be the umbrella term for the scenarios you are thinking of.

The phenomenon, originally from biology, shows up in sandpiles and avalanches as well; it could explain the growth (or lack of it) of mountains too.

[1] https://en.m.wikipedia.org/wiki/Punctuated_equilibrium

For any particular mountain or mountain ranger there could be a number of processes, some of which may dominate for periods of time.

It could be slow / fast growth followed by slow / fast sinking / decay / collapse / asteroid impact / weathering.

I image there have been a number of sequences that have played out in various locations over time.

Not to answer your question exactly, but you may want to look into the works of https://en.wikipedia.org/wiki/William_Ruddiman

He has hypothesised that the tectonic uplift and weathering of the Himalayas has had profound impact on Earth's climate and atmosphere.

Why are you assuming a linear growth model for it in the first place?
Linear is conservative in this case. One would expect the growth rate to shrink as the mountain grows.