Development of Structural and Stratigraphic Frameworks in Subsurface Geological Models

Thomas R. Fisher

Structural and stratigraphic frameworks are the most critical elements of subsurface geological models. Frameworks serve as topologically correct, spatio- and temporally-referenced, geologically valid envelopes bounding properties and processes modeled from the prototype. As a whole, subsurface geological models consist of two main components; one descriptive, one predictive. Descriptive components are mathematical representations of structural and stratigraphic elements, rock, fluid and other properties, and dynamic physical and chemical processes. These elements may also have associated "boundary conditions." Similarly, the predictive components are derived from model calibrations, validations, and simulations of geological processes.

One technique for creation of robust structural and stratigraphic frameworks uses an interactive, object-oriented approach. This method develops frameworks using objects familiar to the geoscientist (e.g., fault, bed, unconformity) in a true three-dimensional visualization environment. Object models honor stratigraphic tenets (e.g., sequences, lateral and temporal relationships, correlations) and permit structural geometries and topologies to be properly imprinted on the stratigraphy. The models are scalable and support distribution of attributes within the described volumes and determination of parameters for simulations. Valid framework models have utility in GeoScientific Information Systems (GSIS), geological, engineering, and risk analysis.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California