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The Kazhdumi Formation is regarded as one of the most prolific hydrocarbon sources in the Zagros Foldbelt and adjacent offshore. Rock-Eval pyrolysis data were collected from 2300 rock samples of the Kazhdumi Formation in 64 wells (core and cutting) including 37 oil and gas fields and five outcrops. 200 Vitrinite reflectance measurements were carried out to calibrate and map thermal maturity over the study area. Palynofacies analyses and thermal history modeling were applied on the wells located in the study area.

Based on the total organic carbon (TOC) map, the Kazhdumi Formation TOC values range from 0 to 11%. In the central part of Dezful Embayment, its average value is about 5%, while average TOC value of the Kazhdumi Formation is lower than 0.5% in Qatar-Gawbandi Paleo-high. Hydrogen index (HI) values represented types II and III kerogen for central part of the Dezful Embayment and Qatar-Gawbandi Paleohigh, respectively. T-max ranges from 370 to 455 degrees C in the study area, the maximum and minimum values for this parameter are recorded in the central Dezful Embayment and central Persian Gulf anticlines, respectively. Vitrinite reflectance (VRr) map also confirms the concluded results of T-max data. Reconstructed burial history and thermal modeling of three wells are also in full agreement with the results of other maturity evidence (T-max and VRr). Palynofacies analyses revealed that this formation in the central Persian Gulf (South Pars Field) clearly represents the dominance of terrigenous elements which were resulted from a close proximity to a fluvio-deltaic source. However, towards the northwest, amorphous organic matter (AOM) dominates in central Dezful Embayment indicating a distal dysoxic-anoxic environmental condition. (C) 2015 Elsevier Ltd. All rights reserved.