The Upper Cretaceous (Campanian-Maastrichtian Abiod formation) has never been considered as a particular drilling target in the Pelagian Bloc (Sahel) onshore east of Tunisia. With the discovery of oil in Maamoura followed by Sidi Kilani (SLK), the Abiod formation carbonates have become the focus of further exploration interest in northern and central Tunisia. This study presents a petrophysical analysis carried out to evaluate rocks properties of the Abiod formation in Pelagian Basin. Shale volume, lithofacies, porosity and water saturation were identified from well logs. Porosity was empirically driven from available core data from 3 wells P1, P2 and P3. The results show that the Abiod formation represents vertical and lateral sedimentary variations with good quality reservoir facies in P3.
The Pelagian Basin is located in northeast Tunisia and has been an area of significant interest in the past few years. The Abiod formation of Campanian-Maastrichian Period is widespread in the Pelagian Basin. It is a producing carbonates reservoir.
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. During Upper Cretaceous, the deposits in the East of Tunisia correspond to the Abiod, Aleg, Douleb, Bireno, Bahoul and Fahdene formations. A set of different data helped to identify an extensive Cretaceous phase (Touati, 1985). These Alpine and Atlassic phases decrease from the West to the East, where strongly folded and faulted zones can be observed (Haller, 1983; Bédir, 1995; Khomsi et al., 2006).