GEOTHERMAL AND HYDRODYNAMIC STUDY OF HYDROCARBON RESERVOIRS IN NORTH-WEST TUNISIA CORRELATION WITH POTENTIAL SOURCE ROCKS, SHALE GAS AND OIL

The North-West Tunisia provides invaluable geological series that contains potential petroleum rocks of high organic matter content. The main source rocks (shale gas or oil) identified in Northern Tunisia is of Cretaceous and Tertiary age.

The nature of hydrocarbons observed, can be subdivided into two main types: Oil seeps and Asphalt impregnations.

The oil seeps are often associated with the contacts between the Triassic and Miocene sands, are typically encountered at Oued el Beji, Jebel Kef Boudabous, Ain Rous es Souani (Jebel Cheid), Fej el Hadoum, Jebel El Goutrania, Ksseb Dam, Sidi Ameur (Jebel Serj) and in the Boujabeur and Jebba mines,

The viscous asphalt and bitumen impregnations are mostly located in fractures and in cap-rock developed over Triassic domes. Examples of such impregnations are observed at Lakhouat, in the Boukhil and Kebouch mines and at Zag Ettir.

These source rocks can constitute an objective of exploration of the shale gas or oil once the potential and the geothermal evolution of the basin are determined.

Several independent approaches were implemented: Geothermal, geophysical surveys, geochemistry and hydrodynamics will be presented in this paper, they helped to identify the geothermal evolution of the basin and consequently to locate the zones producing shale gas and or oil.