Abstract
Chemometric analysis was performed on 19 crude oil samples from 14 different oil fields to reveal oil families and their distributions in the Northern Dezful Embayment Zone. The geochemical characteristics and candidate source rock(s) of the defined oil families were also investigated in this study. The chemometric classification revealed three different oil families in the studied area. Group I includes Naft Sefid, Ramin, Kupal, Martin and Aghajari oil fields. Group II comprises Ziloie, Masjid-e Soleyman, Karanj, Haftkel, Balarud, Qale Nar, and Karoun oil fields, and group III contains Azar and Dehluran oil fields. All studied samples were expelled from open marine settings with anoxic conditions, type II kerogen, and marine organic matter inputs. The group I oil held, have C29/C30 > 1, TAR<1, moderate C22/C21 and C24/C23 tricyclic terpanes, an insignificant amount of Oleanane, mid-oil window maturity, and an average carbon isotope of -26.98‰, which were charged from the Kazhdumi source rock. The group II oil family has C29/C30H < 1, moderate C22/C21 tricyclic terpanes, TAR<1, moderate C24/C23 tricyclic terpanes, and a high Oleanane Index (average of 22%), mid-oil window maturity, and average carbon isotope of -25.35‰. These oils were originated from the Pabdeh Formation. The group in samples have C29/C30H > 1, high C22/C21 tricyclic terpanes, TAR<1, low C24/C23 tricyclic terpanes, mid-oil window maturity, and an average carbon isotope of -27.67‰, which were originated from the Garau or Sargelu settings.
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