Abstract
The Jdeir Formation, a shallow carbonate platform deposit, was developed during the Lower-Middle Eocene epoch in the northwestern Libyan offshore. The diagenesis of the Jdeir Formation mainly involves marine phreatic, meteoric phreatic, and burial stages. The phenomena range from crystalline degradation (micritisation, dissolution) to crystalline aggradation (cementation, neomorphism). Stylolitisation and fracturing are common, mostly filled by bitumen and later with calcite. The result of different diagenetic histories reflects the variation in the amount and kind of porosity within the formation. Porosity in the reservoir is complex and contains primary and secondary types.
Concentration of calcite spar, fracturing, compaction and pressure solution caused destruction of porosity.