Historical:Malden Till Member
H. B. Willman and John C. Frye
The Malden Till Member of the Wedron Formation is named for Malden, Bureau County.
The type section is the Malden South Section (table 6) in roadcuts 2 miles south of Malden, SW SE SE Sec. 5, T. 16 N., R. 10 E.
It is bounded at the top by the darker gray, very clayey Yorkville Till and at the base by the pink Tiskilwa Till.
Extent and thickness
The geographic distribution is shown in figure 6.
The Malden Till Member consists of silty, locally sandy, yellow-gray to gray-tan till with discontinuous beds of sand and gravel. It differs from the Yorkville in having a higher ratio of garnet to epidote (table 4). Data on grain size, clay mineral composition, and color of the matrix of the till are given in table 3.
Age and correlation
The Maiden Till is in the mid-part of the Woodfordian Substage of the Wisconsinan Stage. It was deposited by the Peoria, Princeton, and Harvard Sublobes of the Lake Michigan Lobe.
|Stratigraphic Code||Geo Unit Designation|