The Niagara Escarpment: Ledge Park
This is an EarthCache and
as such there is no container to find. An EarthCache is simply a
place to go and learn about the world we live in. You will be asked
to answer a few questions and to submit a photo in order to log
this as a find. To log this EarthCache you will need a GPS and a
camera or altimeter.
Ledge Park, covers 83 acres along the Niagara Escarpment
providing excellent views of the Horicon Marsh and the surrounding
countryside. The Park has over 2 miles of well groomed hiking
trails ( http://www.dodgeparks.com/pdf/Map-Ledge.pdf ) which pass
through the bluffs, woods and prairie areas. The park is open from
8am to 8:30pm. Dogs must be leashed at all times. Park entry is
free.
For this EarthCache you will visit a scenic overlook and walk a
trail through Niagara Escarpment exposures. Be prepared: wear good
hiking shoes and pack typical supplies such as bug spray and a
first aid kit. Due to the steep nature of bluffs please take
special care if you bring children to the park. The Ledge Rocks
trails and the Ledge Overlook Trails do have 30-50 foot drop-offs
and are NOT recommended for small children. The Upper Woods and
Lower Woods trails are much more family friendly. At no time will
you be required to leave the trail.
The Niagara Escarpment
The Niagara Escarpment is a 650-mile long escarpment in the United
States and Canada that runs westward from New York State, through
Ontario, Michigan, Wisconsin and Illinois. The escarpment is the
most prominent of several escarpments formed in the bedrock of the
Great Lakes. It was named for it's most prominent feature, that
being the cliff over which the Niagara River forms Niagara Falls.
In Wisconsin the escarpment extends for approximately 230
miles.
Formation and Composition
The Niagara Escarpment's primary bedrock type is dolomite.
Dolomite was formed from accumulated sediments of an ancient sea
405-425 million years ago during the Silurian Period of the
Paleozoic Era, it's main ingredient being calcium and magnesium
carbonate which came from the decomposing shells and skeletons of
primitive sea life. The escarpment is rich in fossils including
brachiopods, cephalopods, crinoids, and corals. These fossils
represent creatures that lived in the sea and helped to create the
materials that made up the escarpment. Wisconsin's state fossil the
Trilobite is abundant in some old quarries.
Erosion
The escarpment was carved out over millions of years through the
erosion of rocks of different harnesses. The escarpment features a
cap of erosion-resistant dolomite rock which overlays weaker, more
easily eroded weather shale rocks, that when gradually eroded
leaves a series of cliffs. Errosion occurred in many ways including
the actions of ice, wind and water. This process of erosion can be
most dramatically seen at Niagara Falls, where the river has
quickened the process. Also hastening the process of erosion was
the Ice Age.
During the Ice Age huge glaciers advanced and retreated several
times over North America. In Wisconsin the ice age, began 23
thousand years ago and covered Canada and the northern United
States with a layer of ice 2 or 3 kilometers thick. In addition to
the cutting action of the glaciers, when the ice melted away 10
thousand years ago the rivers and streams also helped to carve out
the now visible cliffs of the escarpment. In some places the ground
is shallow, because the glacier scraped away the cover and in other
places furrows on rock surfaces can be seen where stones in the
glacier gouged them. In many areas the glacier deposited huge
masses of sand, clay and stones. Because of this, the Niagara
Escarpment is not visible everywhere. In such places, only steep
slopes can be seen.
* To claim this
EarthCache *
Complete #1 and either #2 or #3 below.
# 1. Park at N43 27.908
W88 35.079 (Ledge Rock hiking trail).
Hike to N43 27.952 W88 35.092 where you will find a lone tree
surrounded on all sides by the escarpment.
E-mail me how tall is the largest formation circling the
tree.
#2. Upload with your log
a picture (including your GPS) taken somewhere in the
park.
#3. Park at N43 28.076
W88 35.061.
(The view is great but there is no vehicle access in winter)
Go to the Scenic Overlook at N43 28.100 W88 35.026.
E-mail me the elevation on the bluff.
(The valley shown below is about
1,000 feet above sea level.)
http://www.dodgeparks.com/parks-ledge.html
http://en.wikipedia.org/wiki/Niagara_Escarpment
http://encarta.msn.com/encnet/refpages/RefArticle.aspx?refid=761565838