Depositional history and sequence stratigraphy of Tirgan formation (Barremian-Aptian) in central Kopet Dagh, NE Iran

摘要: The Tirgan Formation (Barremian — Aptian) is exposed in the Kopet Dagh northeast Iran. Two stratigraphic sections Radkan and Chenaran were measured. Their thickness are 238 m 119 m, respectively. This formation measured consists of three parts (including lower carbonate, middle limy shale marl upper carbonate rocks). Based on study 164 thin-sections, 15 2 siliciclastic lithofacies have been identified. Carbonate deposited a ramp platform fore shoal, lagoon tidal flat environments. Sea level changes during Cretaceous led to different large-scale depositional sequences (two) present highlights reconstruction tectonic history area Cretaceous.