Abstract:
Petrographical and geochemical assessments of source rock (Darnah Shale) and reservoir (Darnah Limestone) in the offshore well Al-NC 128 in the Cyrenaica Basin were achieved in the present study. In the Darnah Shale, the biomarkers indicate the mixed inputs of aquatic plankton and terrigenous organic matter deposited under suboxic conditions. The kerogen is of types II/III and III. The source rock has a fair quality. The reservoir contains medium crude oil. This oil belongs to source rock of the Darnah Shale as proven by oil-source rock correlation. C1 is the main gas in the reservoir. Both crude oil and source rock are located in the immature window. The Darnah Reservoir has been charged with hydrocarbons in two different times. The middle shale can be considered a cap rock in the petroleum system of the Darnah Formation.
