Library Guides: Geology: Stratigraphy

Stratigraphy

Definition - the study of rock layers and layering. Stratigraphy can be used to determine the relative age of rocks (the age of one rock unit based on its relationship to other units in the area). This section includes links to various stratigraphic charts, including one for Illinois.

Generalized Geologic Column of Illinois
A simplified version of the Illinois geologic column showing the types and ages of rocks in Illinois.
Handbook of Illinois Stratigraphy
Willman, H. B., eds., 1975. Handbook of Illinois stratigraphy. Urbana: Illinois State Geological Survey.
Geologic Formation Names Lexicon (GEOLEX)
This is the digital version of the Lexicon of North American Geology, an index to publications on and information about named geologic rock formations in North America.
North American Stratigraphic Code
Procedures for naming and classifying geologic rock units from the North American Commission on Stratigraphic Nomenclature.
International Chronostratigraphic Chart
A geologic time scale developed by the International Union of Geological Sciences, originally published in Episodes, which is provided by the International Commission on Stratigraphy.
STRATA (Stratigraphy Web Site [SEPM])
an openly accessible site that provides information to explain sedimentary geology, from the basic to complex. It includes pages on sequence stratigraphy, sediments & rocks, paleontology, and an illustrated dictionary of terms related to sedimentology.