RECENT STAGE 



5,000 



( Alluvium ) 



< 



I- 



CO 



-z. 

 o 

 o 



CO 



VALDERAN 

 SUBSTAGE 



(Alluvium ) 



11,000 



TWOCREEKA N SUBSTAGE 

 '^ 12,500 



/ALDERS 



< UJ 

 qCQ 



8^ 





c5: 



LAKE BORDER MORAINES 



(Alluvium and 



Hi^r^ifcuTf c5 •^ - VALPARAISO MORAINES 



aeposiTs; |oe^^"MARSEILLES MORAINES 



K|Of^£J^r__ CROPSEY MORAINES 

 QlCf^^^cftT— BLOOMINGTON- NORMAL MORAINES 

 ■CT*^' __ LEROY- CHAMPAIGN MORAINES 



^^I^SntrBYVlG-E MORAINES 



— '"^ ^"^ iiiu -TzAtorfon loess 



— 22,000 ^^ -"^ , 



FARMDALIAN 

 SUBSTAGE 



Farmdale 

 silt and peat 



28,000 — 



rrrr 



/ 



? 



y^ Winnebago drift 



<^ 

 Zl- 



|_0D 

 _J 3 

 < 00 



C: 



E 



3 



\ 



Inferred southern limit 

 of glacial ice in the 

 Lake Michigan lobe. 



X 



% 



•X, 



rnin 



50,000- 70,000 

 SOIL 



Fig. 75. A graphic representation of the advances and retreats of the ice 

 margin of the Lake Michigan glacial lobe during the Wisconsin stage. Sug- 

 gested dates are derived from radiocarbon determinations. South is to the 

 left; the farthest ice advance shown is in the vicinity of Shelbyville, Illinois. 

 Presumably the various ice advances coincide with periods of cooler weather 

 considerably to the south of the glacial margin itself. (After Frye and Willman.) 



