CompuServe Messages

I understand the hypothesis, I think. I'm a little hazy on where the original Taconics were and whether there are modern traces, But it's quite clear from the sediment sequence that there was a land mass to the East of New York in the Upper Ordovician, so I'll take that on faith. I might point out that the modern Taconics are something of a problem as they appear to have been thrust faulted in from the East, and that needs to have occured when there was no intervening mountain range — unless you want to hypothesize thrust faulting a big block of countryside up one side of the mountains then down the other. If the modern Taconics were emplaced during the Taconic or Acadian Oregenies then why didn't they erode along with the monster mountains to their East? I don't have any problem with the Acadian Oregony. There's lots of evidence I think. My problem is with the Applachians as a product of the Alleghenian orogeny. It's clear that the mountains are post Pennsylvanian and pre-Cretaceous. It's also clear that they are (in most places) a folded structure and now that we've decided that continents move (I'm old enough to remember when they didn't) that a continental collision is a handy mechanism for creating them. The difficulty seems to be that, the only available continental collision probably occured 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. So we have decided that the mountains we see today for something like 3000 km are the result of the mountains having eroded flat then being pushed up again in post Cretaceous time. All I'm saying is that Deus-ex-machina re-emergance theory would look a lot better if there were a mechanism identified to cause it.