Mark E Odegard¹, William G Dickson², John Dombrowski³

(1) GETECH Inc, Stafford, TX
(2) DIGs, Stafford, TX
(3) First Exchange Corp, Houston, TX

ABSTRACT: GIS-Based Structural, Tectonic and Tectono-Stratigraphic Study of the MSGBC Basin: Mauritania, Senegal, The Gambia, Guinea Bissau, Guinea Conakry

The object of this study was a better understanding of gross prospectivity of the MSGBC Basin by reassessing sediment thickness, heat flow regimes, and structural and tectonic framework. We used an ArcView(tm) GIS environment, both to enable faster and more precise methods of interpretation and to allow digital presentation of results. Work began with correlating geological features from published studies to mapped gravity and magnetic anomalies displayed as geotiffs (geo-referenced images). This resulted in reinterpreting, realigning and extrapolating many geological features. A depth-to-basement (D2B) map was constructed from the magnetic data using constrained spectral and Euler methods. Structural models were built along selected profiles using gravity, magnetics, seismic profiles, well logs, geological data and D2B work. These models lead to a much improved understanding of the basin configuration.

We have determined well-defined regions of continental, oceanic and proto-oceanic crust and their depths with natural consequences for hydrocarbon maturation modeling. Other results are an improved understanding of the multiple events in the geologic basin history, recognition of a narrow belt of salt basins along most of the MSGBC margin, identification of areas of crust with injected volcanics, and a better understanding of the older failed rift system. A side benefit of the GIS work was the ease of map integration of multiple data sets from the participants and the promise of an improved corporate memory as the project evolves.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado