Oil Ocurence and Migration Pathways in Central and Meridional Atlas of Tunisia

The analysis source rock of the central and meridional Atlas of Tunisia indicates that the Albian Fahdene Fm has a substantial oil-generation potential. The Cenomanian-Turonian Bahloul Fm exhibits fair to high organic content and petroleum potential immature to mature source rock. The Jurassic source rock exhibits fair to good organic content and petroleum potential located in the south of this area. Molecular characterization indicates that most of the produced oils appear to be sourced from a predominantly shaly marine and mature source rock deposited in suboxic to oxic depositional environment. Oil stains located in the northern part of the area seems to be sourced by a marly or argillaceous limestone. Oil-oil correlations and molecular characteristics of selected source rock samples and maturation models suggests that oils were generated from similar source rock and/or organic facies. The Fahdene Fm is the best source candidate to generate these fluid samples. The integration of benzocarbazoles as geochemical molecules tracer has permitted a relative estimation of the lateral migration distance for the different accumulations of the area. Basin modelling outlined the extent of the different petroleum systems in the area and permitted the elimination of the risky prospects for the next exploration phase.