[at-l] Comparing rocks

[RoksnRoots@aol.com (RoksnRoots@aol.com)]

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In a message dated 12/4/2002 4:58:49 PM Eastern Standard Time,
Phil.Heffington@oc.edu writes:


> See the following for rocks in NY (and how the trail could have been built
> around them easily).



       ***  I can tell you right now the Trail wasn't built on rocks in NY to
prevent erosion. If you look at the rest of NY you'll see that the Trail went
straight up many pitches that have now washed out badly with time. If they
were erosion conscious they would have built graded trails.

      The reason is more likely the geology interest of the primarily New
York City residents for whom the New York/New Jersey Trail Conference trail
network was built. NY's trails are located in a rich geological area with
many varieties and classes of rock from sedimentary to igneous. I know for a
fact that the AT in Harriman deliberately accessed difficult outcrops for
this reason. If you pay attention going in to Fingerboard from the south
you'll see that you climb a difficult set of granite ledges while smooth
forest floor ascends besides you. The AT crosses a different terrain and
cross-ridge grain in NJ/NY. Lastly, the glaciers that ripped up the sharp
rocks in Pennsylvania also bared the ridgetops in NY. Then they dropped field
rock and erratics to boot...

     Finally, many european descended Conference members sought to replicate
the talus-type alpine terrain they left behind in europe. Almost all hikers
during the time of construction were day hikers...

      The picture Phil includes is of the Mount Peter puddingstone of which
Belvale Ridge consists. It is made of ancient round and smooth streambed
rocks encased in purple metamorphic (shale?). It is a vertical seam of
dividing rock between the typical Appalachian metamorphic rock seen in the
route 77 cut and the granites of Harriman northward. Long ago this rock was
an alluvial river delta where stream rocks became silted by river sediment.
After millions of years it was compressed underground and converted into the
rock you see under your feet on the AT on Belvale Ridge...