THE ORIGIN OF GUMBOTIL 115 



B. Section in cut on the Chicago, Milwaukee & St. Paul Railway at mile 

 372, one mile west of Murray, Clarke County, Iowa: 



Feet 



4. Loesslike clay, gray to pale-yellowish color on 

 dry surface with irregular Hnes of brown; 

 when damp it is grayish with mottling of 

 yellow to brown colors; stands vertically, 

 upper few feet mealy 15 



3. Gumbotil (Kansan), gray to drab in color, 

 sticky when wet, hard and tenacious when 

 dry; contains a few sihceous pebbles; leached 11 



2. Glacial till (Kansan), oxidized and leached. . 4 

 I. Glacial till (Kansan), oxidized and unleached; 



has many lime concretions 11 



C. Section in cut on Chicago, Milwaukee & St. Paul Railway, one and 

 one-haK miles west of Manning, in the southwest one-quarter of section 18, 

 Warren Township, Carroll County, Iowa: 



Feet Inches 



6. Loess: 



Leached, yellowish-gray on dry surface; 

 yeUowish-brown to buff-brown on damp 



surface; no shells or concretions 7 



Unleached loess, lighter-colored on dry 

 surface than the leached loess, and when damp 

 it is buff with gray streaks. Contains shells 

 and concretions . . . .^ 5 



5. Glacial tUl (Kansan), yellow, unleached, with 

 calcareous concretions; numerous pebbles 

 including granites, quartzites, etc. Below 

 the oxidized, unleached till is gray drift with a 

 few pebbles. It is gumbotil-Uke but effer- 

 vesces freely. It was probably picked up 

 from the gumbotil zone below 5 



4. Soil band containing carbonaceous material . . 4 



3. Gumbotil (Nebraskan), gray to drab-colored, 

 few pebbles. The upper six feet is fine- 

 grained, gray, and is less sticky and gumbotil- 

 like than the lower seven feet, which is leached, 

 but has some calcareous concretions 13 



