Hydrocarbon generation potential and palynological study of the early Jurassic succession (Alan, Mus, and Adaiyah formations)‎ in well Miran-2, Sulaimaniyah, Kurdistan region, Iraq

Abstract EN

The Early Jurassic sediments from Alan, Mus and Adaiyah formations have been studied in oil exploratory well M-2, Miran Oil field, Sulaimaniyah Governorate, Kurdistan Region, Iraq.

Three techniques were used for determining hydrocarbon generation potentiality for these rock units; Rock-Eval Pyrolysis, microscopic study, and Infrared spectrometry.

The Alan Formation has high TOC wt.% content, ranging between 1.47 and 1.82 (average 1.63), and Mus Formation with 0.85 and 1.75 (average 1.3), while the Adaiyah Formation samples are totally with low TOC wt.% ranging between 0.08 and 0.47 (average 0.30).

Although the Rock-Eval Pyrolysis data show good genetic potential of the Alan and Mus formations, the potentiality of dry gas generation is only the chance for generating hydrocarbons if the organic matter reaches the mature stage.

Also the Rock-Eval data reveal the type of kerogen is mostly type III and IV and the organic matters are still in immature stage except one sample from Adaiyah Formation.

The organic matter within these sediments is amorphous and there are neither palynomorphs nor phytoclasts.

These organic matters also are very small and have no fluorescence, which mostly of gas-prone type with no possibility for oil generating.

Five kerogen samples were selected and analyzed by Infrared Spectrometer.

The results from these samples show small variation outcomes with Rock-Eval data as the kerogen type of Alan and Mus formations are mostly type II, while samples of Adaiyah Formation are type IV kerogen, as determined by Rock-Eval pyrolysis.

However the Infrared spectrometers also show vitrinite reflectance around 0.3% and less (Ro ≤ 0.3%) hence immature sediments, this result is coincides with the data of Rock-Eval pyrolysis.

The results of all mentioned techniques were not exactly the same, and show some discrepancies, but mostly indicating to no potentiality for generating any oil and may be some gas generated from Alan and Mus formations.

The Adaiyah Formation is inert and has no potentiality for generating any hydrocarbons in this well