Geologic Stratigraphic Column...

A geologic stratigraphic column is basic reference material for a geologist.  Below is one for the Bighorn Basin with formation names, ages, rock type, major extinctions and the tectonic setting.  Note that thickness on this stratigraphic chart has no resemblance to rock thickness.  The relatively young Cenozoic sediments are the thickest formations and filled the central part of the basin.