Oil-oil correlation using trace metals from selected oil fields, north Iraq

الملخص EN

A collection of 11 crude oil samples from 11 oil exploratory wells in 5 oilfields in northern Mesopotamian basin were subjected for geochemical analysis of trace metals and sulfur.

The crude oil samples were collected from Guwear, Kirkuk, Tawke, Khurmala, and Taq Taq oil fields.

The mean values of vanadium and nickel were 20 and 15 ppm, respectively.

Trace metals configurations and constraints helped to explore the depositional environments and used in the geochemical grouping the oils.

Based on nickel to vanadium ratio, the crude oils were differentiated into five groups: 1) Tawke-3, Tawke-4, Guwear-2, Shiwashok, and Taq Taq-6; 2) Khurmala-1 and Kirkuk-247; 3) Khurmala-2 and Kirkuk-331; 4) Guwear-3; and 5) Guwear-1.

The low ratio of nickel to vanadium (Ni/V<1) in the crude oils of Guwear-2; Shiwashok; Tawke-3; Kirkuk-331; Khurmala-2; Guwear-3; Kirkuk-247; and Khurmala-1 oils indicates oil source of marine environment, whereas, the crude oil source of Guwear-1; Tawke-4; and Taq Taq-6 is non-marine and probably deposited in lacustrine or land.

The oils can be arranged from older and more mature to younger and less mature based on V/Ni as Guwear-2, Shiwashok, Tawke-3, Guwear-1, Tawke-4, Taq Taq-6, Kirkuk-331, Khurmala-2, and Guwear-3.