Depositional Environment and Stratigraphic Evolution of Hartha Formation in Balad and East Baghdad Oil Fields, Central Iraq

Five subsurface sections and a large number of thin the Hartha Formation (age Late Campanian – Early Maastrichtian) were studied to unravel depositional facies environments. The is important as an oil reservoir in Iraq. Petrographic microfacies analysis selected wells from Balad East Baghdad fields Central Iraq, enable recognition three main Sedimentary paleoenvironments. These are restricted marine, shallow open marine environment within inner ramp, deep outer ramp. represents by two asymmetrical cycles bounded below sequence boundary (SB1) contact between Saadi Formations. ramp transgressive systems tract continue with lower part Formation. Two sequences consist system high stand tract, separated maximum flooding surface. happened represented cycle that continues until Shiranish Formation, which overlies