Microfacies analysis, Sedimentary Environment and Sequence Stratigraphy of the Qom Formation in the Naraq area

Naraq section is located at the South of the Qom sedimentary basin in Central Iran. The study of microfacies sedimentary environments and sequence stratigraphic features of the Qom Formation in this area can help to understand the situation of the Qom sedimentary basin. In this study, 111 samples of the Qom Formation in Naraq section in the northwest of Naraq are investigated. Based on field observation and thin-section studies, 6 microfacies related to the lagoon, reef and slope parts of carbonate platform have been recognized.Due to the presence of slope microfacies and skeletal and non-skeletal grains that are transported from the shallow to this environment and the existence of SMF9, bioturbation, Also the presence of barrier / reef sediments, a carbonate shelf depositional environment is suggested for the Qom Formation in Naragh section. In this model, marls of b member of the Qom Formation show more relative depth. Also sequence stratigraphic studies show that the Naraq section is composed of three sedimentary sequences of third- order three types I and one type II sequence boundaries were recognized in this formation.