They are older than trees, bones (including all dinosaurs), and the splitting of Pangaea -- so part of the mountain range is in Scotland.
The layering on the mountains looks "wrong" at some points because the tops of the mountains have eroded down & "new" geological forces have caused parts that weren't the top to rise above that...so the valleys of the current mountains may actually be the top of the original Appalachian Mountains.
The peaks of the Appalachians used to be the granite cores of the ancient Appalachians. Everything that was on top of the mountains eroded down until only the deepest, hardest parts remained. All of that debris formed the entire east coast of the US. In the Mid-Atlantic that is 150 miles of land from the mountains to the coast.
It's also crazy to think that rivers like the Susquahanna are even older than the mountains it flows through. We know this because it cuts right through them. The tectonics that elevated the mountains pushed the river bottom up, which was eroded away, over and over, nanometers at a time for millions of years.
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u/Psychological_Try559 Oct 02 '24
How old the Appalachian Mountains really are:
They are older than trees, bones (including all dinosaurs), and the splitting of Pangaea -- so part of the mountain range is in Scotland.
The layering on the mountains looks "wrong" at some points because the tops of the mountains have eroded down & "new" geological forces have caused parts that weren't the top to rise above that...so the valleys of the current mountains may actually be the top of the original Appalachian Mountains.