Improved Techniques of Stratigraphic Modeling Controlled by Seismic Data : Application to the National Petroleum Reserve, Alaska

Emily Albouy, Geology-Geochemistry Department, Institut Français du Pétrole, 1 & 4, Avenue de Bois-Préau, 92852 Rueil Malmaison Cedex, France, phone: + 33 1 47 52 69 08, fax: + 33 1 47 52 70 67, emily.albouy@ifp.fr, Jean-Marie Laigle, Insitut Français du Pétrole, and Marie-Christine Cacas, Division Geologie-Geochimie, Institut Francais du Petrole, 1-4 avenue de Bois-Preau, Rueil-Malmaison Cedex, 92852, France.

In petroleum exploration, the dense to very dense information on geometries and textures provided by the analysis of 2D and 3D seismic data is counterbalanced by the sparse nature of the of multi-1D data concerning lithology and depositional environment furnished by wells. Stratigraphic modelling, based on approximation of the physical laws controlling the transport and deposition of sedimentary rocks, can allow a more intelligent use of well data to predict the facies and reservoir quality of identified structural leads, source rock quality and distribution, and seal rock composition.

The elaboration of a valid stratigraphic model generally requires the time-consuming construction and calibration of multiple accommodation maps, coupled with trial–and–error evaluation of clastic supply and / or carbonate production parameters and the sediment transport efficiency. This procedure is rarely integrated as routine in exploration.

New algorithms have been developed to allow rapid, automatic determination of optimal supply, transport and production parameters and accommodation maps presenting an optimal fit to the geometries and thicknesses of sedimentary sequences observed on seismic data. Seismic textural attributes can be used as additional control points improving the determination of depositional environments in areas where there is no well control.

This new methodology has been applied to the data of the National Petroleum Reserve, Alaska. As well as providing an on-line aid to the interpretation of stratigraphic surfaces on the seismic data, the stratigraphic modelling algorithms allow the construction and validation of a stratigraphic model describing the lithological content and depositional environment of the substratum.