Micro facies and sedimentary environment of the Qom formation in Verjun-Khur Abad area

Qom Formation in the section of Verjun-KHurabad area constitutes 852 meters of limestones in thin layers to thick layers, marl, gypsiferous marl, sandstones, and lime sandstones. Its lower contact (section a) is abrupt and mild unconformity with lower red formation. Its upper contact (section f) is gradual and concordant with upper red formation. Besides sampling, lithology changes, stratigraphy, geomorphology of stone units was examined. The results led to drawn the stratigraphy log of Qom Formation in the studied area. Petrography and microfacies studies together with field evidences led to recognition of eight carbonated microfacies in different parts of Qom Formation. This microfacies lied on the tidal, barrier, lagoon and open marine environments. The study of facies and their succession in the mentioned area and compare with modern and old sedimentary environment shows that Qom Formation was deposited in a warm marine environment. Also, the facies of Qom Formation in the studied area was deposited in a carbonated ramp environment.