URBANIZATION OF A PROMINENT GLACIAL GEOLOGY FEATURE AND BEDROCK HIGH, ALONG THE WESTERN BOUNDARY, WEST LAFAYETTE, TIPPECANOE COUNTY, IN

Tippecanoe County, northwest Indiana, underwent several episodes of Wisconsin -aged continental glaciation, the most recent receding about 13,000 years ago. The Wabash River, a major Indiana stream, divides the county into Lafayette on the east and West Lafayette on the west. Purdue University is located in West Lafayette on the high terrace of the Wabash River. A glacial depression that semi-parallels the Wabash River lies 2.5 to 5 miles to the west of the river. Lying at a higher elevation than the Wabash, this depression apparently served as a high level overflow for the river during periods of maximum glacial runoff. A bedrock high lying just to the west of the depression suggests an association between these two features. Depth to Mississippian bedrock in the county averages over 200 feet but along the bedrock high the depth ranges from 0 to 50 feet. Housing needs include development of residential water supply wells, septic tank fields and basement excavations. Alluvial and outwash materials in the depression are contrasted with the fine grained glacial till in the uplands. The bedrock high, consisting of a low permeability siltstone, also complicates the water supply situation. Examination of the glacial depression shows that it is occupied in part by Indian Creek flowing to the southwest and Burnett’s Creek flowing northeast and connecting in a complicated fashion to the Wabash River upstream of Lafayette. New imagery developed on Google Earth at Purdue University, highlights the nature of the glacial depression and its development during the withdrawal of ice from the area.