djwini
WGA Member
Joined: 2004-03-31
Posts: 475
Location: Hales Corners, WI, United States
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 Posted:
Wed Sep 05, 2007 10:29 am |
 
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GC1C8E Breakneck Cache
Not reading the cache description left us in for a wonderful surprise. this cache is located in the Waupun area. we parked at N43 38.806 W88 34.932.
walked in from the trail, and wow, this fantastic view. if you are in the area, don't skip this one.
The Niagara Escarpment is a 40- to 100-foot cliff that passes through the eastern third of our state, continues north of several of the Great Lakes, sometimes under water, into Canada, and down to Niagara Falls. From there it enters the Appalachians, where it is crumpled and folded, then goes south into Pennsylvania, Ohio, Indiana, and back through Illinois into Wisconsin.
This cliff is the edge of a vast sedimentary rock layer, one of several in the layer cake of sediments that formed on the bottom of ancient seas. This layer is like a giant saucer, with its western edge in Wisconsin, and its eastern edge at Niagara Falls. Some layers were composed of erodible material, others of limey material from the bodies of marine life. The Ledge is a hard limestone layer called Niagara dolomite, and it contains fossils of the simple life forms existing at that time. The Ledge is 400 million years old. The Rockies are only 70 million, and the Appalachians 300 million.
When the seas receded, the edges of the layers were exposed and most of them weathered into obscurity. The Niagara layer has retained its cliff edge because the layer beneath it is soft shale, which erodes quickly, leaving the dolomite overhanging. The dolomite eventually breaks off again and again, forming a new cliff face each time -- just as it has at Niagara Falls, where the process is so dramatic that it can be measured in miles per century.
One other thing is responsible for the look of the Ledge: Ice. Mile-thick moving ice of successive glaciers obliterated the cliffs in some places and created huge fissures and crevasses in others. Although the cliff would be higher and sharper today without the glacial bulldozing, the crevasses and caves are left as great places to explore. |
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