Palynofacies and hydrocarbon generation potential of the upper Triassic Kurrachine Formation and lower part of the Baluti Formation, Mosul Block, Northwestern Iraq

Three exploration wells were selected near Mosul city (Az-29, Bm-15, and Kd-1) to study the palynozones and hydrocarbon generation potential of the Upper Triassic Baluti and Kurrachine Formations. This study was completed in two phases: The first was a study of palynofacies and their paleoenvironmental indications, degree of preservation, diversity of palynomorphs, and organic maturity of the rocks according to palynomorphs’ color using a refracted light microscope. More than 80 slides of organic matter were used for this study. Four palynofacies were tentatively recognized. (1) The first palynofacies is diagnostic of the Baluti Formation in the Az-29 and Kd-1 wells; (2) The second palynofacies appeared at different depths in the Kurrachine Formation in three wells. (3) The third was only found between the depths of 4,534 to 4,685 m in the well Az-29. (4) The fourth was only found between 3,500- and 3590-m depth in the well Bm-15. A distal coastal marine environment is suggested for the Baluti Formation and restricted lagoonal environment for the Kurrachine Formation. The second phase used organic geochemical analyses to confirm the suggested paleoenvironmental and hydrocarbon generation material. Three techniques were used, namely total organic carbon, pyrolysis, and pyrolysis gas chromatography, on more than 35 samples from different depths in three wells. The analyses proved that a sufficient quantity of organic matter occurs that and has suitable maturity for hydrocarbon generation potential of oil and gas.