Facies analysis, sedimentary environments and sequence stratigraphy of Sachun formation in Zarghan section (folded Zagros zone)

The Sachun Formation is one of the lithostratigraphy units in south-west of Iran. This Formation in Zarqan section with thickness of 259.6 meters consists of various layers of colored shale/ marl, evaporate and carbonate sediments. It sandewiched between Tarbur and Jahrom Formations. Its lower contact with the underlying Tarbur Formation is unconformable, but its upper contact with overlying Jahrom Formation is conformable.Recognized facies of this formation sediments in Zarqan Section (folded Zagros zone) comprise carbonate, evaporate and terigenou which divided in two facies belt of tidal flat and lagoon. Totally 11 facies and sub-facies have been recognized; 5 tidal falt, 4 lagoon and 2 terrigenous facies. Abundance of shallow facies against lack of deep facies indicates that the Sachun Formation have deposited in a ramp platform. Due to Sequence stratigraphy study of this formation in Zarqan section, one sedimentary sequence has been determined with a type one sequence boundry in its lower contact with Tarbur Formation.