GEOPLAY; a knowledge-based expert system; a model for exploration play analysis
Betty M. Miller · 1995
GEOPLA Y is a knowledge-based expert system designed to perform as a diagnostic consultant or intelligent guide to assist the geologist in the recognition, identification, and characterization of the geologic conditions used to define potential petroleum plays, prospects, and reservoirs as input to an exploration play-analysis model.It also provides the geologist with capabilities to document major basin components such as stratigraphy, structural geology, and sedimentation in order to evaluate the traditional concepts of source, reservoir, and trapping mechanisms.GEOPLA Y incorporates three basic sets of unique geologic conditions to characterize play-specific, prospect-specific, and reservoir-specific properties for the play-analysis model.These specific geologic conditions are evaluated for each identified play within a basin and constitute the basic geologic data for the expert-system's model.These geologic data are defined in terms of characteristics such as geologic age, lithology, environment of deposition, depositional systems, stratigraphy, structural style, organic types, and effective porosity used to evaluate source-bed and reservoir-bed conditions and trapping mechanisms.GEOPLA Y is a knowledge-based hierarchical system that follows the order of geologic reasoning used by an expe-'fienced geologist to arrive at a logical set of conclusions relative to the favorability of the geologic conditions under evaluation for prospective plays and prospects within a basin.The knowledge-based structures in GEOPLA Y are made up of classes, objects, attributes, values, IF-THEN Rules, and Goals, the concepts and constructions of which are described in this report.These elements work together to represent the knowledge and relationships linking the various geologic criteria within GEOPLA Y's knowledge-based system.The GEOPLA Y expert system results in a better knowledge representation of the geologic relationships among basin, play, and prospect characteristics than do other methodologies currently available.It also provides a better means for the geologist to more effectively incorporate inexact information into the expert system to accommodate the uncertainties inherent in the geological data used for play analysis.