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 the Hormozgan Province and on the Gavbandi highland. This field is one of the important gas production anticlines in the SW Iran. The sequence stratigraphy studies are based on seismic data segregation, outcrop observation, and study of thin sections related to cores and cuttings and study of petrophysical logs. The sequence stratigraphy studies in subsurface sections to identify sedimentary sequences of a well is not easy always, because many wells do not have core or are not continuously extracted from them. It is also difficult to study of cutting, especially when samples intervals are high, but well logs are available for almost all wells. In the absence of core and cutting data, these graphs (well logs) are useful tools for investigating sequences. One of these logs is the gamma ray log that petroleum geologists use to differentiate reservoir zones as well as adaptation between different wells in a field. The cyclolog software to use of gamma ray log and analyze it, providing a log that the sequence surface are completely separated and easy to identify, as well as easy matching of identified surfaces. Input data are cyclolog software, raw data of resistivity, gamma ray, neutron, density and son ic logs. But since diagenesis has less effect on the gamma log, it is used more frequently. The cyclolog software creates a log to called INPEFA (Integrate Predicate Error Filter Analysis). The basis of this log is that wavelet analysis is performed in a window of specified length specified by the user. Then, based on the results, the trend of the log is then aggregated into the next predicted stage and their trend is shown as a graph. According to the general principles and methods of sequence stratigraphy, the Kangan Formation using facies features and their equivalence with petrophysical logs, especially gamma ray log, the parasequenes accumulation pattern, sequence boundaries and their relationship with surface fluctuations seawater has led to the identification of two third-order sedimentary sequences (at the time of the formation of the third-order cycles, sea-level changes are global and not dependent on local variations) with type-II sequence boundaries. The basis for the determination of sedimentary sequences in this study is the INPEFA log obtained from the cyclolog software. Considering the trend of the curve in the wells of the gas field studied and changing the range of this curve, positive and negative trends and according to which stratigraphic boundaries (sequence boundaries and maximum flooding surface) are identified. Each sequence consisted of one positive boundary surface (match to the sequence boundary) and one negative boundary surface (match to the maximum flooding surface) and in total two wells (wells \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"A\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\" and \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"B\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\") was identified six positive boundary surface and four negative boundary surface. By integrating relatively more complete data from the petrographic study of well-B, the classification of each system tract was accurately verified.

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