ORGANIC GEOCHEMICAL ASSESSMENT OF JURASSIC POTENTIAL SOURCE ROCK FROM ZAB-1 WELL, IRAQI KURDISTAN

Abstract

The studied samples were collected from Butmah, Adaiyah, Mus, and Sargelu formations in Zab-1 Well which lies about 25 Km to the south of Kalak town, Erbil Governorate. The hydrocarbon potential parameters, including type and amount of bitumen and kerogen, and thermal maturity of eight samples were assessed using Rock-Eval pyrolysis techniques. In general, Sargelu Formation samples have PI values of 0.15 – 0.25 (average 0.19) and Tmax values varying between 422 °C and 431 °C (average 427 °C), indicating thermally immature to early mature oil. They can be considered as poor to fair source, where TOC (Total original Carbon) content ranges from 0.27 to 0.77 of percentage weight (average 0.48). The Mus, Adaiyah, and Butmah formations’ samples are considered to be poor source rocks with TOC content of 0.39, 0.64, and 0.44 wt. percentage, respectively.Samples of Sargelu, Mus, Adaiyah, and Butmah formations contain kerogen types II, III, and mixture of types II and III indicating marine and non-marine organic matter derived mainly from algae and higher plants organisms suggesting oil and gas prone sources.