Limestone and dolomite are exposed along the Lake Michigan shoreline and locally inland. In the interior of the region, thick glacial drift covers bedrock. On the sand lake plains, common landforms include transverse dunes, sand spits, beach ridges, and large deltas. Broad outwash plains are located along the entire northern edge of the proglacial lakes. Ground moraine is extensive at the western edge of the section.
End moraine is common along the northern edge of the section near Lake Superior.
Soils of the sand and clay lake plain, which are quite extensive in the section, are largely poorly drained or very poorly drained, supporting extensive peatlands and swamp forests. Soils of the extensive outwash plains are generally excessively drained sands. The sandy and loamy tills near the southern edge of the section are quite variable in drainage class and depth to underlying bedrock. At the northern edge near Lake Superior, there are sandy tills and outwash. Open bogs occurred on kettle lakes within end moraines and pitted outwash.