Remote sensing and GIS investigation of glacial features in the region of Devilʹs Lake State Park, South-Central Wisconsin, USA

This study utilizes Landsat TM, ASTER and Synthetic Aperture Radar (SAR)-derived DEMs in conjunction with Geographic Information Systems (GIS) in order to reevaluate previously-published interpretations of glacial landforms in and around Devilʹs Lake State Park, south-central Wisconsin, USA. Devilʹs Lake sits in a gorge carved into the southern flank of a doubly-plunging syncline known as the Baraboo Hills through which the Wisconsin or some other river flowed prior to the last ice age. During the last glacial maximum about 18,000 B.P., an outlet glacier of the Laurentide Ice Sheet called the Green Bay Lobe extended southward into south-central Wisconsin and left behind extensive glacial landforms such as moraines, drumlins and eskers. During advance of the Green Bay Lobe into the region, Devilʹs Lake Gorge was plugged at both ends by glacial deposits and resulted in formation of Devilʹs Lake. The Wisconsin River, if it originally flowed through Devilʹs Lake Gorge, found a new course to the east of the Baraboo Hills Syncline. This study utilizes the aforementioned remote sensing data to spatially image the following features: (1) Original extent of the Green Bay Lobe, (2) Moraines and streamlined glacial landforms as indicators of ice-flow directions, and (3) Former path of the old Wisconsin or some other river prior to being rerouted by the Green Bay Lobe. GIS analysis is also performed in order to test published interpretations of the regional glacial history. This study confirms that glacial features observed today are consistent with the former advance of the Green Bay Lobe into the area, formation of glacial Lake Wisconsin, plugging of Devilʹs Lake Gorge by a moraine to form Devilʹs Lake, and subsequent glacial retreat leading to the breaching of an ice dam and catastrophic flooding by ~ 14,000 years ago. The large aerial coverage of satellite imagery with resolutions up to 15 m are valuable for reevaluating regional interpretations previously based on local field mapping and aerial photography of limited extent.