Investigation of reservoir quality of the Kangan Formation based on petrographic and petrophysical studies: A case study of wells "A" and "B" in the gas field of the Tabnak Anticline, SW Iran

The Kangan Formation (Early Triassic) is one of the most important gas reservoirs in the Zagros fold-thrust belt. The study area is located in the west of Hormozgan Province and on the Gavbandi highland. This field is one of the important gas production anticlines in the SW Iran. To investigate the reservoir quality of the Kangan Formation in these wells, 163 microscopic thin sections were prepared from 97.68 m core for petrographic investigations. Then, petrophysical study was out carried using wireline well logs such as spectral gamma ray (SGR), sonic (DT), density (RHOB), and effective porosity (PHIE). The petrographic studies led to the identification of facies features and diagenetic processes affecting the quality of reservoir in the studied wells. These diagenetic processes include chemical and physical compaction, various cementation (especially anhydrite cement), fracturing, dissolution as well as different types of porosity resulting from these processes. Also, for the purpose of accurate evaluation, petrography studies with wells, matching and reservoir characteristics of these wells were qualitatively and quantitatively interpreted and reservoir potential horizons were determined. In general, for the first well (well "A") four and for the second well (well "B") three reservoir horizons were investigated.