The trail has yellow blazes which are at times hard to see.
There are 9 stream crossings in those 1.5 miles, but in summer,
fall, and winter the water level is very low and most can be
crossed without getting your boots wet. It will however take some
hiking skill. Do not attempt this EarthCache
during times of high water.
To get to the Devil’s Fork Loop you must take a National
Forest Service road for about .3 miles to a parking area at 36
49.111N 082 37.594W. Follow the road to 36 49.167N 082
37.737W. At this point look to the left of the road for the
yellow blazes. The trail and your geological adventure starts
here.
At the coordinates for Devil’s Fork Sedimentary Rock you
will encounter a wall of sedimentary rock which is a bank on the
Devil’s Fork creek. The creek has over time cut a grove on
the land to expose this rock.
Sedimentary rock is a type of rock which develops on the bottom
of lakes or oceans. Millions of years ago the area on which you
stand was at the bottom of a large shallow sea. Gradual flow of
water and heavy rain would bring sediments to the bottom of the
shallow sea which over time would become compressed and turn into
rock.
Layering can often be seen in sedimentary rock. The deposition
of sediments is not a constant process. At some times the sediments
are deposited much faster than at other times. Heavy rain or wind
can deposit a layer which becomes compacted and then later another
layer can be deposited. This causes a contact zone to be formed and
a layer to exist. Erosion can then expose these layers as at this
spot.
There are different types of sedimentary rock. These types
are:
1. Sandstone- made up of sand grains cemented together.
2. Shale- made up of clay particles smaller than sand which
makes it smoother
3. Conglomerate- made up of usually quartz pebbles cemented
together
4. Limestone- made of calcium carbonate often deposited by sea
life
5. Dolomite- like limestone but with more magnesium in it
6. Coal- composed by the remains of plants and animals
To receive
credit for a find you must post a picture (optional) of yourself in
with the wall of rock in the background and answer the following
three questions:
1. How tall is
this wall from stream bed to top of the bank?
2. How many
layers can you count from the stream bed to the top of the
bank?
3. What type of
sedimentary rock do you believe this to be?
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