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Unformatted text preview: Shawangunk outcrops, and in
the turbidite sequences in the Martinsburg Formation.
0.0 mi/0.5 mi
0.4 mi/0.9 mi From Stop 1, continue on Scenic Drive.
Stop 2. Park on right on gravel road
leading to picnic tables. Stop 2
TO MONUMENT N DRIVE
EN ER R (ONE WAY) 2/10 OAD Geology – Surficial - Small boulder
field, and mechanical weathering.
Bedrock - Shawangunk Formation. mile STOP 2 PICNIC
on gravel SC 0 TO
MONUMENT 0.4 mile KUS Location - Port Jervis South
quadrangle, main ridge of Kittatinny
Mountain, 4000 feet north of Route
23, east side of Scenic Drive. 0.0
Explanation - The small, ovalSTOP 1
shaped boulder field was produced
by freezing and thawing.
of the boulders were dislodged
from adjacent outcrops of the
Shawangunk Formation, and fell
directly downslope where they were further moved by creep. Over
time they accumulated at the base of the slope. Parts of the boulder
field are collapsed. This shows that some of the boulders may have
previously fallen onto a small block of remnant ice. Some boulders
form crude stone circles, and many have been reoriented to a
near-vertical position (tombstone orientation), presumably by frost
heave and tree growth. Many have also been split apart by root
growth and by the expansion of freezing water (fig. 15).
23 The Shawangunk Formation here dips southeastward and forms the
eastern limb of the same anticline seen at Stop 1. The northwestdipping limb of the anticline lies on the west side of Lake Marcia
(fig. 6). The fold’s core contains the Martinsburg Formation,
26 1 foot fracture Figure 15. Stop 2: Split boulder showing the effects of freeze and thaw along a
fracture. which crops out on the eastern side of the parking lot and along
the service road leading to the lake.
Other occurrences - Boulder fields are found throughout the park in
three settings. The first is in hollows, swales, and saddles along the
main outcrop belt of the Shawangunk Formation. Here they typically
lie below large out...
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