Abstract

Seismic stratigraphy and its geological counterpart, sequence stratigraphy, have become important working tools in oil and gas exploration. The purpose of this paper is to clarify principles which govern the development of seismic sequences and their bounding surfaces in a foreland basin setting such as the Western Canadian Basin. To achieve this goal, a numerical model of progradational sedimentation was created which simulates large-scale basin filling processes. The model and its implications regarding depositional facies and sequence stratigraphic interpretation are discussed.

The strong asymmetry in subsidence rate across foreland basins has important consequences for sequence development. Relative sea level may be rising in axial basin settings at the same time that relative sea level is falling on structural arches and along the basin margins. These variations in relative sea-level change have profound effects on the stratal patterns, environmental facies, and the nature of the bounding surfaces of sequences forming in different parts of the basin.