ABSTRACT

This study investigates the upper part of Sargelu Formation (Middle Jurassic) in the Erbil Governorate of the Kurdistan Region, Iraq. Two field campaigns covered two different areas, the Warte and the Barzewa sections. These two locations are located in the Imbricated Zone. In total, almost 33 samples were collected for both sections. 
The goal of this work was to study the geochemistry (major, trace, and rare earth elements), kerogen type, potential of source rock, origin of organic matter, and maturation of the upper part of Sargelu Formation. as well as the recovery of the hydrocarbon component from the solid phase to the liquid phase.
 Based on the illite crystallinity (IC), the upper part of Sargelu Formation (Warte and Barzewa sections) was subjected to the anchizone stage. Calcite, dolomite, and quartz are the predominant non-clay minerals in the Sargelu Formation.
The concentration of major oxides are as CaO > SiO2 > MgO > Al2O3 > Fe2O3 > K2O > P2O5 > TiO2 > Na2O > MnO. These trace elements V, Zn, Sr, Mo, Ba, and Cu have the highest ppm ratio of the Sargelu Formation.
The Al2O3/TiO2 ratio, SiO2 (wt.%), and (TiO2 vs. Al2O3, Th/Sc vs. Zr/Sc, and Zr versus TiO2) plots suggested that the provenance of the source rock of the Sargelu Formation is almost intermediate igneous rock. The Sargelu Formation seems to have a complicated tectonic setting (passive-active margins) that was reconstructed their tectonic setting by the ternary diagram (La, Sc, and Th) and the binary diagram of (K2O/Na2O vs. SiO2).
The V/(V + Ni) , V/Cr, TOC/TS ratios, and V vs. Ni diagram reveals that the depositional environment of the Sargelu Formation nearly tends to be  anoxic and dysoxic conditions.
The total average of the TOC for upper part Sargelu formation is 3.23%. The Sargelu Formation seems to be dominated by kerogen type III, and the organic matter was thought to be of terrestrial origin. The source rock potential of the Sargelu Formation suggested to be generated gas-prone depended on the HI and SP. This study declares that the Sargelu Formation is predominant in the over-mature stage of the source rock according to the IC, Tmax, and OI.

The results indicate that the recovery phase contain alkane, alkyne (C-H) and alkene (C=C) hydrocarbons as well as alcohol compound (C-O and C=C) and carboxylic acid. By using the ultrasound homogenizer process, the hydrocarbon component (C-H bond) can be recovered from the solid phase and transferred to the liquid phase.