524 



A. G. LEONARD 



Fig. 2. — Pre-Wisconsin till overlying Fort 

 Union beds on Tobacco Garden Creek several miles 

 above its mouth, McKenzie County. 



melted, the waters flowing from it deposited much outwash silt in 



the form of valley trains sloping away from the moraines. A 



number of the morainic hills have been partially buried by the 



outwash silt and rise 

 like islands from the 

 level plain of the valley 

 train. The morainic 

 belt of bowlder-covered 

 hills and ridges is found 

 near the base of the 

 slopes on either side of 

 the two valleys tribu- 

 tary to that of the Little 

 Heart River (Fig. i). 

 Moraines cross the 

 valley in three places 

 and one belt of ridges 



and hills continues unbroken along the south side of the valley of 



the South Branch for a distance of 12 miles. The cultivated fields 



extend up to the moraine 



and end there where the 



soil becomes too rocky 



and the slopes too steep 



for cultivation. 



DRIFT IN MC KEXZIE 

 COUNTY 



Near the western f*. 

 boundary of Xorth ^ 

 Dakota the pre- 

 Wisconsin ice sheet '■^"■ g!re ^ a 

 reached 35-40 miles 

 south of the Missouri 

 River and thus covered 

 the greater part of McKenzie Count}- which lies between the 

 Yellowstone, Missouri, and Little Missouri rivers. The older 

 drift left by this ice sheet is well shown in many places in this 



Fig. 3. — Pre-Wisconsin till resting on stratified 

 sand and gravel on Tobacco Garden Creek, near its 



mouth. 



