[Journal
entry for February 2, 2008]. Today is a bit brighter than yesterday, with
its heavy rains, but is still rather cloudy.
I am visiting the tension cracks along the Hudson Palisades cliffs that
are south of State Line Lookout. I have
walked past them many times since noticing them for the first time more than a
decade ago, but I have never really given them a close look.
I park at the Lookout and
take the Long Path southward, along the edge of the cliff. According to a sign, the cliff is 532 feet
high in this area. The trail first descends down into a deep gulley – a cleft
in the cliff that reaches about half way down. I follow a well-engineered rocky
staircase down the north side. I pass a very impressive rock spire, a big
polygonal column of basalt. I then cross a little brook at the bottom of the
gulley. Overhanging banks with dangling
tree roots suggest that rapid erosion has been occurring here. I then huff back up to the cliff top. I pass the
Crack System 1.
The first of the cracks is located just a little past the tower. It’s a narrow
feature and easily missed if your attention is focused on the spectacular river
view that’s on the other side of the trail. Perhaps that’s why it’s enclosed by
a now-ancient and dilapidated green guardrail.
A fall into the crack easily could be fatal. It has steep sides and in some places is ten
feet deep. Looking around, I find a few
dark crevices that extend further down another ten feet or more. The general area actually has two
cracks. The second is to the west of the
first and not as well-developed, or at least no rock faces are exposed on the
earth’s surface. The crack is
recognizable mainly from the sag in the land.
These two sub-parallel cracks are each about a hundred yards long, and
parallel the edge of the cliff.
This area must have been the
site of an old habitation. One
depression in the ground is lined by blue tile – the remains of an old swimming
pool. And the vegetation includes some
hedges, that while now untrimmed and growing wild, nevertheless look very much
out of place.
The tension cracks are
indistinguishable from the many similar cracks that I have seen on the volcanic
Crack System 2. I continue along the trail to the second
crack. It’s much larger than the first,
a steep-sided gorge or chasm, twenty or thirty feet deep and a hundred feet
wide, with a small stream flowing down its middle. Unlike the first set of
cracks, which are wholly within the material of the cliff, this one intersects
the cliff edge. I spot one area along
the northwestern side of the chasm where some recent displacement has
occurred. A small subsidiary crack has
recently opened, separating a small slice of rock from its connection with the
chasm’s side. A sloping pile of soil on
the top of the slice indicates that this crack opened rather recently, probably
this year. The crack appears deep, but
whether it extends beneath the level of the stream is unclear to me.
I am, of course, interested
in knowing whether these cracks have had any recent activity. Certainly the guard rail suggests that they
are old features that predate the building of the Park in the
nineteen-thirties. Perhaps they date to
the end of the Ice Age, and were caused by the unloading of the
I walk down into the chasm,
following the stream, being on guard all the time for the possibility of
hard-to-see and very hazardous cracks at its bottom. I do indeed find one of these, on the
southern side of the chasm up against a vertical rock wall. It’s a sink hole
about a yard wide that extends down into the earth to a depth of at least
twenty feet. A little water is dripping
into it, and I can hear more water gurgling at depth. I soon discover that the stream that I have
been following does not run the full length of the chasm and so does not create
a waterfall at the cliff edge. Instead, with no drama, it simply ends in a damp
patch of old leaves. I presume that
another sink hole lurks under those leaves, but I fear to get to close.
I return to the cliff top and
walk to the little rocky point of land, just south of the intersection of the
chasm with the cliff edge. It affords a
nice view of the
Crack System 3.
The cliff edge trail rejoins the Long Path south of the chasm and itself now
runs along the cliff edge. I follow it
to where it crosses a small stream. Unfortunately, the ford has been blocked by
the fall of a large tree. The new ford has fewer stepping stones and is harder
to cross than the old one. I notice, for the first, time that this stream is
itself flowing in a shallow trough might well be another tension crack. I follow the stream south, and sure enough,
it disappears in another patch of leaves and sand. The region of this sink hole has some nearby
bedrock that I can stand safely on, so I approach cautiously and poke a long
stick down into the debris. The stack sinks easily to the depth of a foot or
so, like in quicksand, but does not break through to any sort of cavity. The trough develops into a well-defined
tension crack south of this sinkhole – one with steep sides and piles of
angular blocks. This well defined crack
peters out again into a shallow trough, which goes on to intersect the
cliff-edge. Overall, this crack is
several hundred yards long.
The Long Path crosses several
more streams. One crossing is via a
fairly well-built foot bridge across a narrow but section of stream. I think
that the stream bed in this are is not natural, but rather has been
specifically engineered to create a waterfall in a carefully chosen section of
the cliff edge. I any case, the
waterfall there is quite lively and picturesque – thanks to yesterday’s rain.
Crack System 4. I walk another half-mile south on the Long
Path to the last of the crack systems (or at least, the last of the ones that I
know about). It is another wide and deep
chasm that is set very close to the cliff edge.
It is spanned by a sturdy steel footbridge. I cross it and stand atop the rather thin
stone sliver that makes the eastern wall of the chasm. The sliver is not so narrow to be especially
dangerous. It’s at least five feet wide
even at its narrowest, and in most places is more like ten or twenty. But it’s still daunting to stand in such an
exposed place. The Palisades Cliffs are
themselves very vertical at this spot, and very high. One deep sinkhole is
visible in the chasm itself, towards its southern end – dark and of unknown
depth.
I return to State Line
Lookout, mostly using the Long Path, but taking a diversion to the west just
south of Federation Memorial Tower, so as to be able to loop around the big
gulley, rather than climb down into and up out of it again. I’ve hiked at a leisurely pace today. The overall trip took about two and a half
hours.