Low Elevation
< 360 feet above mean sea level
Low Place
Bonpas Creek
Low Quad Name
Grayville
Low PLSS
2-16-3S-14W
Low Geology
Cahokia Alluvium
High Elevation
> 550 feet above mean sea level
High Place
unnamed hilltop
High Quad Name
West Salem
High PLSS
3-31-2N-11E
High Geology
Illinois Vandalia till upland over Pennsylvanian Mattoon Formation
Area
220.38 square miles
Total Relief
190 feet
Percent Slope
1.21%