Eastern offshore Tunisia.
The CHENINI block is located in the Gulf of Gabes. It corresponds to a transitional zone between the Mesozoic Jeffara Maritine Basin and the Ashtart Tripolitain Basin. This zone is characterized by Mesozoic-Cenozoic platform mixed facies including shales, sandstones, carbonates and evaporates. It is also affected by Early Mesozoic distensional faulting, mainly NW-SE trending with wrench component, and by Mid-Cretaceous to Miocene Alpine folding.
Reservoirs and Seals
Main reservoirs include:
- The Ypresian El Guaria nummilitic carbonate are producing hydrocarbon further northeast (Ashtart, hasdrubal and Didon fields).
- The Coniacian Douleb oolitic carbonates and the Lower to Middle Turonian Bireno bioclastic carbonate are producing oil further northwest (Miskar Gas field).
- The Upper Cenomanian Zebbag Dolomite exhibit a good reservoir parameters generally enhanced by fracturing. This reservoir made of pervasive dolomite produce, oil in the nearby Ezzaouia and El Biban fields.
- The upper Jurassic M'Rabtine sandstone constitutes the major reservoir in Ezzaoui oil field.
- The early Meloussi Sandstones is producing oil in the Robana and Mazrane Oil fields .It could be considered as the most promising reservoir in this block.
- The secondary objectives in the block include the Barremian Sidi Aïch sandstone, the Aptian Orbata Dolomite and the Middle Jurassic Krachoua Dolomite. The seal of these reservoirs is provided by the intraformational shales, which exhibit a high seal capacity.
- The primary and mature source rock in the area is the Callovian Smida shale Further source intervals with TOC content up to 3%, are intercalated with the Aptian Orbata.
- Towards the North (near Ashtart field), the Cenomanian-Lower Turonian Bahloul carbonates are a proven source rock.
- Some shales intervals within the Meloussi formation could constitute a source rock of interest.
The trap types in the block are structural or combined structural and stratigraphic, including anticlines, faulted anticlines, titled fault blocks, salt diapirs, facies change and unconformities-related traps