A NOTABLE TYPE PLEISTOCENE SECTION 



STRATIGKAPIIIC SECTION 



The following stratigraphic section is shown : 

 Post-Bloomington: 



Feet 



8c. Soil, light gray, loessial 1- 1% 



8b. Leached loess, brown, jointed by roots and surface weathering, 



thickness about 3% 



8o. Calcareous loess, yellow, no shells found, thickness 0- 2% 



Wisconsin gravel and till: 



7. Bloomington gravel, discontinuous, brown, limestone pebbles pres- 

 ent beneath calcareous loess, absent for a few inches directly be- 

 neath leached loess, thickness 0- 4 



6. Shelbyville till, typical pebbly clay till with lens of gravel 8-10 feet 

 thick on east side and about 10 feet below the top, the gravel con- 

 tains till balls; till oxidized yellow in upper 2-6 feet with very faint 

 maroon or orange tinge, bluish-gray below where damp, light-gray 



on dry surface, with slight maroon tinge, calcareous, thickness 32 



Peorian: 



5. Loess, grayish yellow, with rusty streaks and spots, fossiliferous, 

 shells fragile and larger ones crushed and difficult to extricate, 

 cleavage planes through the loess made by the pressure which 

 crushed the shells, calcareous throughout, humus streak 2 inches 

 thick about 10 inches below the Wisconsin till, contact with Wis- 

 consin till sharp, thickness 6 



Sangamon : 



4. Old soil, dark with flakes of carbon, some fragments of old wood in 



east part of cut, loessial in texture, non-calcareous 1- iy 2 



3. Loesslike silt; on east side brownish in upper 1-1% feet, grading 

 below into grayish-yellow, 2-2% feet, and again into brownish with 

 carbon specks, 3-4 feet, the lower 2 feet showing slight trace of 

 effervescence with acid; no effervescence in upper 5% feet; no bed- 

 ding or stratification. On west side this loesslike silt is bluish-gray 

 with greenish cast below the old soil, the soil and about 6 inches of 

 the greenish loess is leached; calcareous below, very compact, no 

 bedding or stratification, scattered small pebbles in lower 3 feet; 



thickness same on both sides of cut 7- 8 



Illinoian: 



2. Gumbotil, chocolate brown, with reddish specks on east side, brown- 

 ish to brick red at top with bluish-green spots on west side, tena- 

 cious, hackly fracture, siliceous pebbles, mostly under % inch, non- 

 calcareous, shear zones on west side, thickness about 4 



Grades into: 

 1. Very calcareous till, few small lime concretions at top, limestone 

 pebbles prevalent, grayish, mostly covered with wash and slump to 

 base of cut 41 



