20 ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 461 



PLEISTOCENE SERIES Thickness 



SANGAMONIAN STAGE (feet) 



Glasford Formation 

 Berry Clay Member 



8. Accretion-gley; Sangamon Soil; sand and clay with some silt 

 and dispersed small pebbles, leached, dark gray mottled 

 with dove gray and streaked with light brown, massive (P-7170 

 from mid part); top of this interval is several feet below the 

 original land surface because of excavation work. 7.0 



ILLINOIAN STAGE 



Glasford Formation (undifferentiated) 



7. Till, leached, oxidized, rusty brown, sandy silty to sandy, 



pebbly but lacking cobbles and boulders (P-7169). 1.5 



6. Till, calcareous, compact, jointed, contains cobbles and 

 boulders, gray, gray- brown and lavender-gray, massive, 

 silty sandy to sandy silty; upper part oxidized along joints 

 (P-7168 upper; P-7167 middle; P-7166 lower). 14.0 



5. Sand and silt with some clay, calcareous, gray and tan 

 (P-7165); sand and gravel lenses up to 5 feet thick occur 

 laterally along the cut at this position. 1.5 



4. Sand and silt, oxidized, loosely cemented with limonite, weakly 

 calcareous to calcareous, rusty brown to reddish brown (P-7164); 

 irregular to crenulate with irregular boundaries and thickness. 1.5 



3. Till, calcareous, dense, compact, tough, pebbly and cobbly, 

 massive and jointed, gray to gray-tan (P-7163 upper; P-7162 

 lower) . 7.0 



2. Till, consists of 5 percent silt with small stems and wood 



fragments and fossil snail shells, calcareous, contorted, com- 

 pact, gray streaked with tan (P-7161); contains pebbles but 

 few cobbles. 4. 



Petersburg Silt 



1. Silt, with some clay and fine sand, calcareous, gray becoming 

 dark gray to black downward, compact; contains twigs, stems 

 and other wood fragments and fossil snail shells, all becoming 

 more abundant downward; locally contorted; upper part contains 

 a few dispersed pebbles and the contact with the overlying till 

 is not distinct because of incorporation of similar silt in basal 

 part of till (P-7160 upper; P-7159 lower); to water level in bor- 

 row pit. 5. 



Total 41.5 



HARMATTAN STRIP MINE STRATIGRAPHIC SECTION NO. 3 



Measured in mine drainage ditch, SW| NW^ NWj Sec. 4, T. 19 N 

 12 W., Vermilion County, Illinois (1969, 1970). 



