Productivity Assessment for Unit A of the Late Triassic Kurra Chine Formation from a Well in the Bina Bawi Oilfield, Iraqi Kurdistan Region

Unit A of the Triassic Kura China Formation has been studied from a productivity assessment point of view in the selected BB-4 well of Bina Bawi Oilfield, Iraqi Kurdistan Region, to identify its productive potential. The study is done based mainly on the available full sets of wireline log data for the gross penetration of 323 m of the unit. The lithology was identified depending on the data from the porosity logs and appeared to be mainly composed of dolomite, anhydritic dolomite, and anhydrite with rare limestones. The data from the Gamma-ray indicated low shale content (less than 10%) at the upper part of the unit, whereas at the middle and lower parts, shale and shale intervals are common. The existing shale in the studied Unit A is mostly distributed as dispersed clay materials between the grains. The porosity of the unit was evaluated depending on the calculated corrected Neutron-Density combination log and showed that the unit is of poor porosity, being on average less than 5%. The permeability in the BB-4 well was obtained from the data of the Nuclear Magnetic Resonance (NMR) log and showed a lot of impermeable or poor permeable horizons. Depending on the differences in the shale volume, porosity, and permeability values, three reservoir units were selected for the unit under study. Hydrocarbons with different saturation percentages exist along Unit A of the Kurra Chine Formation in the studied well, and most of the existing hydrocarbons are non-movable (residual hydrocarbons). The calculated net-to-gross (N/G) reservoir, pay, and productive ratios for the studied Unit A collectively in the well BB-4 appeared to be 9.2%, 3.28%, and 3.28%, respectively.