John C. Frye and H. B. Willman
The Waukegan Member of the Lake Michigan Formation (Lineback et al., 1970, p. 6) is named for Waukegan, Lake County.
The type section is the interval 0- 16 cm in core 143, the same core as the type of the South Haven Member.
Extent and Thickness
It is distributed widely over the offshore lake floor except at a few places where bedrock or till form the lake bottom. It is 0.1-30 feet thick.
It is the surficial sediment of the formation in large areas in the center and along the eastern side of southern Lake Michigan.
It consists of soft sandy silt, silty clay with a high water content, sand, and gravel. The member becomes sandier near shore and in the southwestern part of the lake. A gray silt facies occurs on the east side of the lake where the member is thickest, and a brown silt facies is on the west side where the member thins to less than a foot thick (Lineback and Gross, 1972).
LINEBACK, J. A., and D. L. GROSS, 1972, Studies of Lake Michigan bottom sediments- No. 10. Depositional patterns, facies, and trace element accumulation in the Waukegan Member of the late Pleistocene Lake Michigan Formation in southern Lake Michigan: Illinois State Geological Survey Environmental Geology Notes 58, 25 p.
LINEBACK, J. A., N. J. AYER, and D. L. GROSS, 1970, Studies of Lake Michigan bottom sediments- No. 3. Stratigraphy of unconsolidated sediments in the southern part of Lake Michigan: Illinois State Geological Survey Environmental Geology Notes 35, 35 p.
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