The rock which forms Natural Tunnel
State Park is sedimentary rock. This rock can be divided into two
broad types. These two types of rock are carbonate rocks and
siliciclastic rocks. Two types of carbonate rocks are limestone
(formed from the shells of once living organisms) and dolomite
(sedimentary rock rich in magnesium). The siliciclastic rocks are
composed of clay minerals and quartz with small amounts of mica and
feldspar.
The formation of Natural Tunnel began
over a million years ago. When water contains carbon dioxide from
the atmosphere it forms a weak carbonic acid. This carbonic acid
traveled through crevices and slowly dissolved the limestone and
dolomite bedrock. Once the crevices widened Stock Creek was
probably diverted to continue carving out the tunnel by erosion.
The water found a channel through the tunnel by way of the Glenita
Fault. In this way large sinkholes opened on each side of the ridge
and the tunnel was left behind with Stock Creek flowing through
it.
Legend holds that Daniel Boone was
probably the first white man to see the tunnel but he left no
record of it. Lt. Col. Stephen H. Long explored the tunnel in 1831
and published an article in a geology journal in 1832. In 1890 the
South Atlantic and Ohio Railroad laid tracks through the tunnel. It
is still used today to carry mainly coal through the
tunnel.
The listed coordinates take you to
Natural Tunnel’s Lover’s Leap. You will take the
Lover’s Leap Trail which is a very nice half mile walk along
the rim of the gorge. At this point you will be standing on the
south rim of what was once a very large sinkhole. Look to your left
and you will see a chimney rock composed of harder rock than the
limestone and thus more resistant to erosion.
To claim a find
for this EarthCache you must post a picture (optional) of yourself
with Lover’s Leap and the chimney rock in the background.
This may be taken at any point along the trail. You must also
answer the following:
1. What is the
elevation at the posted coordinates?
2. Estimate the
height of the chimney rock from the rim to its top.
3. Estimate the
distance from the rim to the railroad tracks below.
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