Palynofacies Analysis and Hydrocarbon Generation Potential of the Tithonian-Beriassian Chia Gara Formation from Selected Wells in Ajil, Hamrin, and Tikrit Oilfields, Northern Iraq

The recovered sedimentary organic matter from the Tithonian-Berriasian Chia GaraFormation was studied from three selected wells of Ajil-12 (Aj-12), Hamrin-1 (Hr-1), andTikrit-3 (Tk-3) in Northern Iraq. Amorphous organic matters appeared to be the dominantcomponents of the organic matters within the formation with more than 93%, whereasphytoclasts and palynomorphs comprised only few percentages. As no intensive variationsobserved in the percentages of the determined organic matters along the studied Chia GaraFormation except a slight increase in phytoclasts and palynomorphs in its uppermost part,therefore the formation considered to be representing only one mainpalynofacies type thatsubdivided into two secondary palynofacies. Using Tyson s APP ternary, the formationappeared to be deposited in a distal suboxic-anoxic basin. As source rock, the formation in thestudied locations contains moderate to very good quantity of organic matters which composemainly of type II and Type III kerogen (separately or mixed). The whole formation has theability to generate oil or gas except the upper part of the formation in the location of the wellAj-12 in which less than the lower limit of the required S2 values for considering as sourcerock is recorded.