CONTENTS. VII 



Chapter IX. — The eakly Wisconsin drift sheets— Continued. ]>:,ge. 

 Section III. Bloomington morainic system — Continued. 



Range in altitude - 245 



Surface contours - 245 



Between western Kane County and the head of Bureau Creek 246 



In Bureau Creek drainage basin 247 



In Bureau, Marshall, and Peoria counties 250 



Between the Illiuois and Mackinaw rivers 251 



Between the Mackinaw River and Ford County reentrant 252 



The reentrant in Ford County 254 



Eastward from the Ford County reentrant to western Indiana 255 



The portion covered by the late Wisconsin drift 257 



The weak moraine in eastern Iroquois County, Illinois - 258 



Cropsey Ridge - 258 



Chatsworth-Cay uga Ridge - - - 259 



Farm Ridge or Grand Ridge 260 



Thickness of drift 262 



Structure of drift : - - • 266 



Character of ontwash - 270 



Intel morainic tracts --- -- 280 



Distribution or extent 280 



General features - - - - 280 



Thickuess of drift 282 



Structure of drift --- - 283 



Kaneville esker and delta .. 284 



Little Rock esker, or " Devils Backbone " .. 286 



Covel Ridge - - - 288 



Onarga Ridge - - 289 



Section IV. The composite morainic belt of northern Illinois 290 



Marengo Ridge 290 



Distribution - 290 



Relief _- 291 



Surface contours 291 



Thickness of drift - -- --- 292 



Structure of drift .293 



Character of outwask 294 



Inner-border phenomena - 295 



Correlations 295 



Portion of the composite belt west of Fox River 297 



General features - 297 



Structure of drift - 300 



Correlations _..... - 302 



Portion of the composite belt oast of Fox River 304 



Distribution and connections - 304 



General features - 305 



Thickness of drift 306 



Structure of drift 306 



Section V. The Marseilles moraine - 307 



Distribution 307 



Range in altitude - 309 



Relief 309 



Surface contours - 309 



Thickness of drift 311 



Structure of drift 312 



Character of ontwash 313 



Inner-border till plain 315 



