Click on the map to see more detailed regional images on shaded-relief backgrounds.
Pre-Wisconsin glacial features of the north-central United States from Illinois to North
Dakota. This map was compiled from various published maps and reports on geology and
geomorphology of the region--see source references. The background
is a color-coded topographic image created from a digital elevation model. Data entry by
John Morettini, Naomi Wilkins and J.J. Zeeberg. Map composition by Naomi Wilkins
and J.S. Aber. This map is part of the pre-Wisconsin glacial mapping project of GAGE work group.
Return to the Pre-Wisconsin mapping homepage.
Last update 31 Oct. '97
Maximum limit Wisconsin glaciation.
Pre-Wisconsin glacial limit; ice border.
Melt-water channel/valley.
Moraine, esker, kame, etc.
Preglacial buried valley.
Preglacial drainage divide.
