The 4D animation of dynamically evolving basins, emphasizing the interplay of porosity and permeability feedback, is presented. This interplay arises from the modification of sediment composition and texture with time in response to imposed stress and temperature fields. This is demonstrated using the numerical simulator CIRF.B.

CIRF.B is a numerical basin simulator implementing fluid flow, kinetically and thermodynamically mediated water-rock interactions, hydrofracturing, and chemical and mechanical compaction. The simulator uses standard well data as basin evolution history input.

An important facet of 4D basin characterization is the nonlinearity and the coupling of various mechanisms. For example, compaction, overpressuring, fracturing, and fluid migration are tightly coupled processes — the locations where these are occurring depend on local conditions, such as pore connectivity and compaction rates, and properties of neighboring sediments, such as the presence of seals. Furthermore, these processes are most dynamic where the basin configuration changes most rapidly.

One result of such phenomena is the formation of petroleum pools away from the source rocks. Due to compaction-fracturing-healing cycling and the availability of flow paths the fluid migration patterns in the past in Piceance Basin of Colorado and Midland Basin of West Texas do not conform to the present-day structure. Thus, by visualizing the conditions that existed in the past, more reliable study of the genesis of various types of petroleum traps can be assessed for today's exploration.

AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah