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Ozarks
geology
Clifty
Creek Natural Area includes natural bridge
By
Conor Watkins
Rolla
The
Clifty Creek Natural Area, which is administered by the Missouri
Department of Conservation, is home to Clifty Creek and a natural bridge.
Clifty
Creek flows through a small canyon in places.
The
Clifty
Creek
Natural
Bridge
is quite scenic and spans a small tributary of Clifty Creek.
The area is pretty all times of the year and some like to visit in
the winter, as the area is much less overgrown.
Both the creek and the natural bridge are scenic and popular among
photographers even though they are relatively remote.
The
Clifty
Creek
Natural
Bridge
was formed when a tributary of Clifty Creek, known as Little Clifty Creek,
undercut a drainage divide and was pirated by Clifty Creek.
It is likely that a cave or joint (fracture) in the rock,
originally served as a shortcut under the rocky ridge and was later
enlarged to form the natural bridge. It
also appears that the same rocky ridge was once home another natural
bridge just downstream. Those
that climb atop the ridge and walk in the downstream direction will notice
that it ends at a steep dropoff with large boulders below.
This was most likely another natural bridge that has since
collapsed.
The
area is home to another smaller natural bridge/cave just 300 or so yards
downstream. This feature is
somewhat similar to Rock House Cave on the Current River.
As with
Rockhouse
Cave
, this small two- entranced cave appears to be the meander of a once
larger cave system that was destroyed as Clifty Creek downcut in its
valley. This two entrances of
this cave remnant are spaced close together along the bluff line and only
separated by a rock pillar. This
cave is small enough to be almost fully explored without a light, with the
exception of a slightly taller dome room is present at the rear. The
taller dome room is off to the right where the cave is darker.
This
cave represents the end stage of a once larger system and its days are
also numbered. The rock pillar
serving to support much of the cave and the bluff above is overstressed
and slowly failing. As rock
pillars are compressed in the vertical direction, they expand laterally
since they are not confined. As
this expansion occurs, tension is induced in the rock.
Rock is roughly ten times stronger in compression than tension so
pieces tend to spall off overstressed pillars, giving them an hourglass
shaped profile. Sometimes
pillars naturally reach a stable geometry that allows them to remain in
equilibrium. It is the
author's belief that this pillar will not reach a stable equilibrium and
will continue to spall until it completely fails, possibly
catastrophically. The pillar
is highly fractured and exposed to freeze thaw cycles common to Ozark
winters. Rock fragments have
accumulated around the based of the pillar, indicating that the process
has continued to progress in recent times.
When the pillar fails, it is likely that much of the bluff above
will also come crashing down. Secondary
jointing in the bluff is parallel to the face, creating a preferential
failure zone once the pillar gives way.
Such a failure may happen tomorrow or thousands of years in the
future.
Although
the cave is officially called "
Unnamed
Cave
#7", it has at least two local names including
Clifty
Hollow
Cave
and Red Man's Cave. Local lore
indicates that an Indian used the cave as a residence during the earlier
part of 1900's, giving the cave this name.
Clift
is an archaic English word meaning cliff.
Clifty Creek was most likely named because of the bluffs and cliffs
in the area. Large cliffs
overhang the creek by 30-40 feet farther downstream of the bridge and make
for interesting pictures. This
section of cliffs is quite large and continues for several hundred yards.
To
get to Clifty Creek, take I-44 west to the Hwy 28 exit (exit 163) and head
north through
Dixon
. After
Dixon
, turn right on Hwy W. Hwy W
will turn to gravel soon. After
passing under some large power lines, be on the lookout for a conservation
parking area on the left. One
can walk down the trail here to the creek and walk about a mile downstream
to the junction of the two creeks and site of the bridge.
One can also walk down the road to an shorter but more strenuous
access point. This location is
reached by walking about a mile to a trail blocked by several small
rounded top wooden posts and rocks. This
location is also on the left side of the road.
Follow this trail and bear right as it heads down the hill.
The trail will join the creek almost right at the bridge.
This point makes for an excellent viewing area of the bridge along
with the vantage from the other side.
To get to the overhanging cliffs, one can either walk about one
half mile downstream or drive farther down the road and park near the next
low water crossing. Simply
walk upstream less than one-quarter mile to the cliffs.
Be aware that the hiking of steep hills is involved and the area
could be dangerous if one were to slip.
Also, be aware that some of the land adjacent to the creek is
private property. “No
Trespassing” signs and purple/pink paint on the trees mark the private
property.
Much
of the
Pioneer
Forest
, which contains Clifty Creek is actually privately owned by Leo Drey and
the LAD Foundation. The LAD
Foundation promotes conservation and outdoor recreation by preserving land
their land while allowing public use.
Many of their lands are administered by other agencies such as the
Missouri
Dept. of Conservation (MDC) and the
Missouri
Dept. of Natural Resources (DNR).
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