The NPS Geologic Resources Inventory (GRI) has developed a Geology-GIS Data Model for implementation in the production of digital geologic-GIS data for parks with significant natural resources. The present GRI Geology-GIS Data Model is based upon the Environment Systems Research Institute (ESRI) file and personal geodatabase formats for storing spatial data within a relational database management system (RDBMS).
A geodatabase stores data in point, line, polygon or table feature classes that can be grouped into feature datasets, or logical groupings of vector feature classes that share the same spatial extent. A geodatabase has the added strength of allowing attribute validation rules, relationship classes and topological rules that maintain data integrity within and between feature classes.
The present version of the GRI geodatabase data model (v.2.0+) makes use of "feature class definitions" to define (geologic) feature classes that share the same geometry and topological (spatial) rules, relationship rules, and attribute field parameters. The data model is used in GRI Google Earth (2.2 KML) and GRI ESRI 10.X Map Service derivative digital map products, however, has ancillary table and database relationships are not supported in these data formats geologic unit (table) information has been limited to a few key fields that have been appended to applicable data layers.
GRI Geology-GIS Data Model and Related Documents