Simulating Geologic Processes in Creating Experimental Sedimentary Basins

John W. Harbaugh

A revolution is brewing in sedimentary geology. Computer models are being developed in three dimensions for simulating the major processes that create and modify sedimentary basins. These processes include transportation and deposition of clastic sediments, reworking by waves, carbonate and evaporite sedimentation, isostatic compensation, compaction, pore-water expulsion, and hydrocarbon generation and migration. While these processes must be simplified for representation in the form of equations and logic operations, simulations can operate with remarkable fidelity. The mechanics of actual processes may be imperfectly known, but computer codes can be developed that parallel current theories and hypotheses, and can be updated to keep pace with advancing ideas.

A principal advantage of process simulation, particularly when three dimensions are represented, is the ability to explore interdependencies between processes. For example, deposition, compaction, and isostatic compensation are strongly interdependent and should be represented in concert in simulation experiments. Furthermore, process models can be devised that scrupulously observe the conservation laws, including conservation of mass, energy, and momentum. Incorporation of these capabilities in itself is a major advance. Another advance lies in close coupling of three-dimensional color graphics display systems, provided by new generations of graphics work stations. The ability to observe the details of a sedimentary basin as it evolves through geologic time is stimulating and thought provoking. However, a major challenge lies ahead in linking experimentally generated basins with actual basins. Three-dimensional graphic display procedures will be critically important for the task.

AAPG Search and Discovery Article #91022©1989 AAPG Annual Convention, April 23-26, 1989, San Antonio, Texas.