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.
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.)