388 
GLACIAL DRIFTS IN MINNESOTA 
east Minnesota, from east to west, a driftless strip of country, a 
“pebbly border of earlier drift,” a belt of “earlier drift sheets,” 
and the “later drift sheets,” This last was the Wisconsin Drift, 
the edge of which is a few miles west of Austin, Mower County 
(No, 5), at the south in Minnesota. The “earlier drift sheets” 
were recognized as separable into two parts by peat beds. These 
authors reserved their opinion (p. 265 and 274), however, as to 
whether the thin, outer border of drift represented the first or the 
second of the two drifts. Therein arose a problem that is not 
settled to this day. 
— It is a well established fact that both Nebraskan and Kansan 
stages are represented by drift-sheets laid down by glaciers in 
Minnesota that covered the whole state excepting the small area 
in southeastern part, as described. The Wisconsin stage is repre¬ 
sented at the surface by drift over all the state but the southeastern 
comer, and a small area in the southwest corner, as shown on the 
map, (plate xxxvi). These three stages are separated by erosion 
intervals, and peat and soil lies between them locally. 
The Illinoian drift, however, was not recognized in Minnesota 
until quite lately. It covered at most only a small part of the 
state on the central eastern border, where it had been mistaken by 
N. H. Winchell and others for a red drift belonging to the Wis¬ 
consin or “younger” drift. It is, to be sure, a “red” drift and not 
“gray” drift as the Kansan and Pre-Kansan are. The field work 
of Frank Leverett, which is now partly published, distinguishes 
the Illinoian from the “red” drifts of the Wisconsin and simplifies 
matters relating to both of these stages.^ 
The “old red” Illinoian, as distinguished from the “young” 
and “younger red” sheets belonging to the Wisconsin stage, brings 
out more clearly the problem of the Iowan (?) stage. This 
Illinoian sheet does not extend down to the state of Iowa where 
the Iowan drift is, and, moreover, it is “red” and not “gray” as 
that drift is supposed to be. There is but one recognized “gray,” 
or Kewatin, drift sheet above the Kansan drift in Minnesota, and 
that one overlies here in part the first “red till” of the Wisconsin 
stage, and is clearly contemporaneous with it for the rest. The 
Illinoian drift of Minnesota does not correspond to the Iowan 
8 Univ. of Minnesota Geol. Surv., Bull. 12, p. 32, 1915; also, Bull. 13, p. 14, 1917; 
and Bull. 14, p. 13, 1919. 
