The studied samples were collected from the Palaeozoic outcrops, Khabour, Pirispiki, Kaista, Ora, Harur, and Chia Zairi formations in Nazdur Anticline, Amadia about 457 km due north of Baghdad, Iraq's capital city. Qualitative assessments of 29 samples were conducted by using textural microscopy in determining the percentage of amorphous organic matter for palynofacies type belonging to different types of kerogen. This organic matter contains acritarchs, spores, and algae deposited in the dysoxic-anoxic environment. The organic matters are from mature to post mature and have a thermal alteration index of-3 to +3 by Pearson's and Staplin's scales, respectively, with palynomorphs of orange to dark brown colors on the palynomorphs. These ranges of colors indicate mature organic matters.
The present study focuses on source rock evaluation of the Sargelu Formation by using core chips of rocks collected from well Atrush-2, Duhok, Kurdistan Region-Iraq. The Rock-Eval pyrolysis and vitrinite reflectance were executed. Subsequently, the selected parameters were used for source rock evaluation and 1-D Basin Modelling calibration. The upper part of the formation mainly comprises argillaceous limestone with low content of organic matter (0.64%-1% TOC). By contrast, the lower part is dominated with shale interval and contains high amounts of TOC values (>4% for 1272-1278 m) reveling good to very good quality source rock. Accordingly, good to very good hydrocarbon generation potential is suggested for this formation. Organic matter of the Sargelu Formation contains type II and mixed-type II-III kerogen. The values of Tmax and vitrinite reflectance (Ro%) demonstrate that the formation is thermally mature and in the oil zone. In order to construct a thermal history of the formation and determine the timing of hydrocarbon maturation and generation, the 1-D basin modelling PetroMod 2019.1 was used in this study. Based on the 1-D Basin modelling simulation and its outputs, about 3500 m of overburden have been eroded at the study area. The present-day heat flow was found to be 30 mW/m 2. The organic matter of Sargelu Formation entered the early oil zone in 64 Ma and reached the main oil zone ca. 5 Ma. The formation is still in the main oil zone at present-day. In well Atrush-2, the highest rate of oil generation for the Sargelu Formation was in the 8.5 Ma, the onset of oil expulsion from Sargelu Formation was in 50 Ma and the expulsion mass has been reached 0.5 Mtons at present-day.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.