THE EARLY WISCONSIN DRIFT SHEETS. 223 



SECTION II. CHAMPAIGN MORAINIC SYSTEM. 



Under this head is discussed a group of closely associated ridges which 

 interlock to some extent, but usually consist of two or three distinct mem- 

 bers. The system receives its name from the city of Champaign, Illinois, 

 the site of the State University. The ridges, which are more or less dis- 

 tinct east from this .city, become united in a single ridge from this city 

 westward. The discussion begins at the westernmost point at which the 

 system has been recognized, and proceeds eastward to the point of disap- 

 pearance beneath a morainic system of late Wisconsin age. In the com- 

 plex portion separate names have been applied to the several members, viz, 

 Outer or West Ridge, Middle Ridge, and Inner Ridge 



DISTRIBUTION. 



The westernmost prominent development of the Champaign morainic 

 system is found in " Blue Ridge," which sets in near the village of Blue 

 Ridge, in northern Piatt County, and leads southeastward into Champaign 

 County. There is, however, a narrow belt, with rather more undulation 

 than is common on till plains, which leads westward from near the north 

 end of Blue Ridge past Leroy to the Bloomington moraine at Downs, and 

 which is doubtfully referred to the Champaign morainic system. This 

 undulatory belt stands 20 to 30 feet or more above the general level of the 

 plain on the south, but the rise is so gradual that the relief is scarcely 

 perceptible. 



The portion known as Blue Ridge comes to the Sangamon River just 

 above Mahomet. With a gap scarcely one-half mile wide the moraine 

 reappears on the east bluff, and leads southeastward to Champaign, crossing 

 the Cleveland, Cincinnati, Chicago and St. Louis Railway west of the city. 

 The width from Blue Ridge to Champaign averages about 2 miles. 



A short distance west of Champaign the Outer or West Ridge sepa- 

 rates from the main belt and passes southward through Savoy and Tolono 

 to West Ridge village, in Douglas County, near which it swings rapidly 

 eastward and joins the middle member of the series in southwestern Ver- 

 milion County. This ridge has an average breadth of scarcely one-half 

 mile in its north-south portion, but in the west-east portion it increases to 

 a width of nearly 2 miles and becomes the principal ridge of the series. 



