Welcome to Indiana Geologic Names Information System
This Web site contains current information on the geologic names that have been adopted and are used by the Indiana Geological Survey (IGS). The site is intended to provide Web-based access to IGS geologic nomenclature to a broad spectrum of users from academia, industry, government, and the general public.
The Web site allows users to access information about specific units by entering a formal stratigraphic name, abandoned name, or miscellaneous unofficial name. Options to select units by specifying system and stratigraphic rank allow users to retrieve data for more than one unit and view the data in alphabetic or approximate stratigraphic order. The Web display shows IGS nomenclature for the selected unit(s), names of equivalent correlative units, miscellaneous and abandoned names, and applicable higher-rank stratigraphic terms. The Web coverage includes each of the five Indiana areas delineated in the Midwestern Basin and Arches Region chart (AAPG COSUNA Chart) and provides information on the geographic changes in rank, lithic term, and assignment to higher-ranked unit.