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Comment by Tagbert | Hacker News Reader

The Cascade Range did not exist during the Cretaceous era. Those mountains arose through subduction and volcanism starting around 37 Mya.

Even if there were mountains around, 2K meters is not that high. I used to live in a town at 2500 meters elevation in Colorado.

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I might be misinterpreting your comment, but the mountains of Spatzizi and BC in general are not part of the Cascades, other than a small area near the border around Chilliwack.

Black rock around white bone could be volcanic ash or mud buried the bones, then pushed down into the mantle just right, heated it under lots of pressure and cooked it all into rock like a kiln?

Heat and pressure like that would convert that ash into a metamorphic rock and destroy any fossils. Surface rocks don’t get down to the Mantle except through subduction where they are melted and mixed with other melted rocks.

If those fossils were buried in ash or mud, the normal rock-forming processes would have fossilized the bone and converted the ash and much to sedimentary rock. You see the same thing in other fossils bearing rocks like limestone and sandstone.

I'm not a geologist, but 2000 m in 37 million years is ~0.05 millimeters per year. Is that about the right rate of growth for mountains formed through subduction and volcanism?

By comparison, the Himalaya (maximum height, > 8800m) are only ~50m years old, are among the fastest rising mountains in the world, and Everest itself has an average growth rate over the period of 0.18mm/yr.

The fastest rising peak, presently, is Nanga Parbet, in Pakistan (part of the Himalayan Plateau), rising at 7mm/yr.

That's 70mm/decade, and 700mm (~3/4 meter) every century.

<https://www.guinnessworldrecords.com/world-records/fastest-r...>

<https://eartheclipse.com/science/geography/how-himalayas-for...>

[Also not a geologist, but] apart from volcanism from subduction, there were also other landmasses being sheared off the subducting plate and accreted onto the western part of the continent. It was all probably higher before the many millions of years of erosion up until now?

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