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Unformatted text preview: m side (east and northeast sides), rock has been removed
by abrasion. This gives the outcrop a characteristic sheepback or
whaleback shape called a roche montonnée.
The Shawangunk Formation here dips southeastward and forms
the eastern limb of an arch or anticline, the same one as that
described at Stops1 and 2. The steeper dip of the rock layers, the
white quartz veins that cut across the bedding, and some small
faults show that the rock here has been more strongly deformed
than those at the previous stops.
Other occurrences - Most rock outcrops in the park show the
effects of glacial erosion. Striations and crescentic marks are best
preserved where the rock retains its glacial polish. Quartz veins
and small faults are found in the beds that were tightly bent during
folding and in beds that were overturned.
0.0 mi/1.6 mi
0.5 mi/2.1 mi
0.3 mi/2.4 mi From Stops 3 and 4, exit parking area
via Monument Drive.
Turn right, follow sign to Dryden Kuser
Gate. Park on paved area on right. Walk
to Stop 5. Stop 5
Location - Port Jervis South quadrangle, Cedar Swamp, Dryden
Natural Area. Park in area near locked gate. Proceed northeast
about 1200 feet along abandoned road to plaque just beyond
pillars. Here Kuser Trail may be traveled to bypass the swamp,
or for a shorter route follow the boardwalk cutoff. The abandoned
road cuts through an area of thin till and bedrock outcrop. Many
of the outcrops exhibit evidence of glacial erosion in their overall
streamlined form and lightly weathered surfaces. The base of the
steep slope east of the road and swamp is covered by a thin narrow
apron of talus.
Geology - Surficial - Swamp deposits, till, talus. Bedrock - Numerous
outcrops of Shawangunk Formation.
A IL BO
Explanation - Cedar Swamp
occupies a north-draining valley
eroded by glacial ice along the hinge
line of an anticlinal axis in the
Shawangunk Formation. During
retreat of the last ice sheet about
18,000 years ago, a small glacial
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