Glacial Landscape

Glacial Landscape. . , The bluff you stand on now is a product of the large volume of meltwater flowing from the Laurentide Ice Sheet which greatly altered the landscape of Wisconsin. As a result, the landscape of the area during the last part of the Wisconsin Glaciation is notably different than that of areas affected earlier in the Ice Age and areas that were never reached by the massive ice sheets. For example, the outermost limit of the last glacier is marked by a conspicuous ridge of deposited debris. The many lakes and wetlands and the irregular landscape that characterize so many areas of western and northern Wisconsin are also a direct result of the last glacier., St. Croix River looking downstream towards Stillwater, MN. Wisconsin bluff is on the left., Trilobite , State Fossil, What is a Glacier? , Glaciers begin to form when snow remains in the same area year-round, eventually enough snow accumulates to transform into ice. Each year, new layers of snow bury and compress the previous layers., How do Glaciers affect Land? , Glaciers not only transport material as they move, but they also sculpt and carve away the land beneath them. A glacier's weight, combined with its gradual movement, can drastically reshape the landscape over hundreds or even thousands of years. The ice erodes the land surface and carries the broken rocks and soil debris far from their original places, resulting in some interesting glacial landforms., The Laurentide Ice Sheet about 11,000 years ago., Get to Know Glacial Landforms: , Drumlin: A low oval mound or hill created from compacted clay molded by past glacial action., Esker: A long ridge of gravel and other sediment deposited by meltwater from a retreating glacier., Floodplain: A low lying area covered with sediments deposited by glacial meltwater., Ground Moraine: A layer of accumulated glacial till and sediment creating irregular topography often resulting in rolling hills/plains., Kame: A mound created when sediment is washed into a depression on the top surface of a glacier and then deposited on the ground below when the glacier melts away., Kettles: A kettle is created when isolated glacial ice is buried beneath glacial till, then melts. If the depression fills with water, it is known as a kettle lake., Terminal Moraine: A moraine deposited at the point of furthest advance of a glacier. Often results in a long ridge being formed.