Geology of the Wisconsin Dells

Geology of the Wisconsin Dells. . , The word "Dells" was derived from the French word "Dalles," meaning flat-layered or slab rock. These layers of rock were formed during the Cambrian period, 500 million years ago, when the North American Continent was completely covered by an ocean, the Cambrian Sea. Layer upon layer of sand and silt formed on the bottom of this ocean and as the water receded, the layers of minerals solidified into sandstone., In the beginning of the Ice Age, approximately 1 million years ago, a series of glacial movements transformed the landscape, tearing of hill tops, filling valleys and leveling out the surface of the earth in the northern and eastern parts of Wisconsin. The Dells was located on the extreme eastern margin of a "drift less' area which was untouched by the glaciers. However, thousands of years later when the glaciers began to melt, the water formed enormous and powerful streams which pushed ice, rock and debris through the sandstone forming the spectacular rugged beauty of the river shorelines. , Today, nature is still sculpturing the Wisconsin Dells, molding and fashioning with wind, water and frost to create some of the world's most magnificent scenery.