The Lithostratigraphic Analysis and Petrophysical Characterization of the Campanian-Maastrichtian Formation in the Pelagian Basin (Northeast Tunisia)

Abstract

The Campanian-Maastrichtian formation was studied and defined in a Pelagian basin, mainly, in the Sidi El Kilani oil field. The carbonates of the Abiod formation are considered as a potential reservoir for several years. The present study aims to characterize the lateral variation in thickness and lithology of the Abiod reservoir based on borehole lithology logs and electrical well logging. This chalky carbonate shows a relevant porosity and permeability variance. Furthermore, the subsurface data have allowed recognizing the internal architecture of Pelagian Basin which is a stable domain, but also a rather a complex structural domain. The sedimentary facies of the Abiod formation (Campanian-Maastrichtian) have been guided by the existence of deep faults and older structures which evolved into major E-W and N-S faults and characterize the geodynamic structures and tectonic framework. The structural framework based on the major structures controls the existence of the deep reservoir and its distribution in the basin. Throughout the reservoir of the Abiod formation, areas are widespread where there is relevant thickness and relevant porosity, particularly along the major faults corridors and in the summit parts of the main anticlines.