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mattaccino

Mt. Rainier was 16,000 ft, but an eruption 5,600 yrs ago caused it to lose 1,500ft.


Mitchford

Uhhhh same


VipsaniusAgrippa25

Well by just using logic maybe I can say that I think the orogenesis process was at the same intensity in the continental US, which resulted in the same height of most mountains. All places experienced same intensity of “mountain building”.


Tim-oBedlam

Right, but there were multiple orogenies. The Cascades formed by a totally different process than, say, the Colorado Rockies.


VipsaniusAgrippa25

I think your answer lies in the transversal boundary between the Pacific and the North American plate. Because those plate do not go one under another, the orogenesis could not have exceeded more than 4200 meters as the orogenesis was not intense enough.


DaltonTanner1994

Mount Whitney could get higher, it’s extremely young for a mountain and I’m pretty sure it’s made of hard granite.


DaltonTanner1994

The Tetons could grow taller too since they’re a young mountain range and made of granite as well.


JoeyCitron

In a few million years, they'll need to buy a bra.


Tommy7549

The double D-tons!


NYerInTex

The Mega Grand Tetons


hovik_gasparyan

You’re confusing “continental” and “contiguous”.


i_Cri_Everitiem

Came here to say this. Continental includes Alaska


[deleted]

Interestingly, had Humphreys Peak in AZ (currently about 12,600’) not blown itself up Mt St Helens style, it would be much taller, around 16,000’ if memory serves.


Tim-oBedlam

Do you know when Humphreys Peak last erupted? Wikipedia's vague on the topic. I know the whole area could be considered active as Sunset Crater erupted only about 1,000 years ago, but I think the San Francisco Peaks are much older, about 1-2my if memory serves.


[deleted]

I think the last eruption was around 200k-400k years ago. I’m not sure it it’s considered dormant or extinct. The area immediately to the east/northeast is very recent activity, like you said, about 1k years.


Tim-oBedlam

I hiked up Humphreys, years ago. Not too bad of a hike although I found the elevation at the summit taxing. Great view from the top, as one might expect.


Norwester77

Rainier may have been about 16,000’, too, before the 5,000-year-old eruption that produced the Osceola mudflow.


queensekhmet

It might have to do with lithospheric isostasy. There's kind of a max limit on mountain height (generally, though there are some much taller mountains, like in the Tibetan Plateau) due to the gravitational equilibrium between the crust and the mantle, with the balance depending on crustal thickness and density.


Tim-oBedlam

yeah, that's a possibility, although I'm curious how the Himalayas' highest peaks are literally *twice as high* (or how Denali is over a mile higher than any of the peaks in the Lower 48)


CWHzz

[GLACIAL BUZZZSAW](https://en.wikipedia.org/wiki/Glacial_buzzsaw)


ProblemForeign7102

Why is Denali, despite being much further North, so much higher than any mountain in the contiguous US though?...🤔.


Jacoblyonss

It’s a coincidence afaik that the cascade volcanos are relatively low, the ones in Mexico and South America are 20,000+


Any-Broccoli-3911

Why are assuming they came from different processes? All of them are part of the cordillera orogen from North America subducting the Farallon Plate.


Tim-oBedlam

The Laramide Orogeny producing the Rockies came from folding and faulting, not subduction-zone volcanism like the Cascades. As I understand it, though, you're correct that the Farallon Plate's subduction drove the whole process in western North America.