The Pinnacle
The Pinnacle is one of several types of outcrops. Among the
types of outcrops are pillars.
Types of Pillars
1. Chimney
2. Monument
3. Pinnacle
4. Pohaku
5. Rock towers
As you can tell by it's name, the Pinnacle is a pinnacle
pillar.
As an outcrop, the Pinnacle is a geological form referring to
the appearance of bedrock or superficial deposits exposed at the
surface of the Earth. The exposure occurs mainly from wind and
water erosion.
The Pinnacle is sedimentary rock that has eroded. The Pinnacle
is composed primarily of dolomite and sandstone.
How Sedimentary Rock is
Formed
For thousands and sometimes, millions of years, little pieces of
our Earth have eroded which is being broken down and worn away by
wind and water. These little bits of out Earth are washed
downstream where they settle to the bottom of rivers, lakes and
oceans. Layer after layer of this eroded earth is deposited on top
of each other. These layers are pressed down more and more through
time, until the bottom layers slowly turn to rock.
What Are Dolomite and
Sandstone?
Dolomite: It is a sedimentary
carbonate rock and a mineral of which both are composed of calcium
magnesium carbonate. The amount of calcium and magnesium is usually
but not always equal. Dolomite most commonly forms in groups of
small crystals. Often dolomite is used to make magnesia, which has
important medical applications. The color of dolomite can be white,
gray, peach, pink and colorless. Rarely it is yellow, green or
black.
Sandstone: is a sedimentary
rock formed by the cementing together of grains of sand. The usual
cementing material in sandstone is calcium carbonate, iron oxides,
or silica and the hardness of sandstone varies according to the
character of the cementing material. The color of sndstone may be
gray, red, buff, brown and rarely green.
The Pinnacle Preserve was once covered by a shallow inland sea
millions of years ago. As the sea retracted and left the
sedimentary rock and the sedimentary rock was eroded by the Big
Cedar Creek and the wind we now have the wonderful Pinnacle Rock.
This same area is also a major watershed (Clinch River) and has a
beautiful waterfall called the Big Falls.
Beside forming the Pinnacle rock, erosion and rock decomposition
had formed the calcium rich soil that which supports many unusual
and rare wildflowers.
During your walk to view the Rock, you will first encounter the
Sykes Cemetery at: (see below
waypoint). Buried here is a Revolutionary soldier,
Private John Sykes. Further down the trail is the Big Falls at:
(see below waypoint). A short
walk from the Falls is the best viewing area for the Pinnacle
Rock.
If you care to walk further, less than .2 mile, you will be at
the end of the trail at (see below
waypoint). Here you will find the confluence of the Big
Cedar Creek and the Clinch River. This is also another EarthCache
(GC1TKFM).
In order to receive credit for this Earthcache you must do the
following:
1. Email me the answers to the following questions: A. What is the
height of Pinnacle Rock, B. The Creek which helped form the Rock
was named after what tree which is found in abundance in the
Preserve?
2. Upload a photo of your GPSr pointing to the pillar or
informational sign. While it would be nice, you do not have to have
to show your face(s) in the photo.
ALL of these requirements must be met in order to receive the
smiley!
This Earthcache was approved by the
Geological Society of America
| We have earned GSA's highest level: |
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