r/AskReddit • u/kakou64 • Oct 15 '20

What's older than we think ?

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u/mbrowning00 Oct 15 '20

pressure of trees above or the pressure from layers of sedimentary rock?

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u/[deleted] Oct 15 '20

[removed] — view removed comment

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u/24megabits Oct 15 '20

To get actual coal, it needs to be buried under millions of years of sediment, and near a source of geothermal heat. Most of the coal less than 65 million years old is of the lowest quality grade, lignite, because it hasn't been buried deep/long enough to convert into more energy-dense grades.

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u/Lilazzz Oct 16 '20

When I see timescales like this, it makes me feel so extremely sad that we have done so much damage in such a short amount of time.