These diagrams from The Environmental Geology of Allen County, Indiana
(Special Report No. 13), published by the Indiana Department of Natural
Resources (1978), show the probable stages of Cedar Creek's development
at the end of the last ice age.
Summary: Sequential Development of Cedar Creek
Cedar Creek Canyon
forms as a sub-ice channel of the Wisconsin Glacier's Saginaw Lobe
The Saginaw Lobe
retreats and the canyon is buried by the advancing Erie Lobe
The ancestral Eel River,
which includes upper Cedar Creek, forms as an ice-marginal channel to the
Cedar Creek Canyon,
now a sub-ice channel of the Erie Lobe takes drainage from the melting
Erie Lobe into the
ancestral Eel River
The St. Joseph River
forms at the edge of the Fort Wayne Moraine and takes drainage from
Lake Maumee to the
Wabash River; Cedar Creek Canyon takes drainage from the St. Joseph to
Outwash from Cedar
Creek Canyon "beheads" the Eel, diverting upper Cedar Creek into the
canyon, making it a
tributary of the St. Joseph
The Maumee River opens
as Lake Maumee recedes; the St. Joseph reverses flow, making the Cedar
part of the Maumee drainage system.
Source: Bleuer and Moore, Environmental Geology of Allen County,
Indiana (Special Report No. 13), published 1978 by the Indiana
Department of Natural Resources. (Out of print. Special thanks to
DeKalb County amateur geologist Ed McDonald for making his copy
Other Reference: Jack A. Sunderman, "The Three Faces of Cedar Creek,"
ACRES Quarterly, vol. 39, no. 4 (Autumn 2000), pp. 6-7, published by
ACRES Land Trust, Inc., 1802 Chapman Road, Huntertown, IN 46748.