#Fold mountains
Don,
>>The difficulty seems to be that, the only available continental collision
probably occurred in the late Paleozoic and there apparently isn't enough rock
missing from the Applachian sedimentary sequence for the Applachians to have
been in place all those years.
The Ouichita/Marathon fold/thrust belt in Oklahoma and Texas is Late Permian
(Wolfcampian/Leonardian) in age. If I remember correctly, the structures
continue on across to the east coast areas, possibly curving back down into
Georgia, and then turning northward. I'm not that familiar with the orogeny
that caused it, but I do know the timing here in West Texas.
Jim