The Upper Jurassic Surmeh Formation in the study areas of the southern Dezful Embayment and the Izeh Zone (Zagros sedimentary basin, southwestern Iran) was investigated in three sections: Fahliyan, Khami, and Mongasht. This research interprets data obtained from petroleum fluid inclusions present in double-polished thin sections prepared from the samples. The data include temperature, salinity, and fluorescence reflectance color. Using this information, the characteristics of these sections were evaluated. The burial depth of the host rock of the fluid inclusions was estimated using the trapping temperature and pressure of the fluid inclusions at the time of their formation in these areas. The predicted depths are 2040 meters for the Fahliyan Anticline section, 2140 meters for the Khami Anticline section, and 600 meters for the Mongasht Anticline section in Tang-e Kord. The Fahliyan section, with a GOI value of 12.96%, is introduced as a reservoir rock with weak oil saturation. The Khami section, with a GOI value of 29.4%, represents a reservoir rock with moderate oil saturation. The Mongasht Anticline section, with an average GOI value of 53.5%, is introduced as a reservoir rock with good oil saturation. The API gravity values derived from the fluorescence reflectance spectra of the petroleum fluid inclusions for the studied sections are as follows: the petroleum fluid inclusions in the Fahliyan Anticline section contain trapped ultra-light oil; those in the Khami Anticline section indicate light oil at the time of trapping; and the oil in the fluid inclusions from the Mongasht Anticline section is classified as medium oil. In general, using the above information, it can be inferred for the studied areas that oil density increases from the Fahliyan Anticline towards the Mongasht Anticline. This likely indicates that the degree of oil maturity increases from the Fahliyan Anticline towards the Mongasht Anticline due to the decrease in the depth of fluid inclusion formation.