Porosity Types and Relationship between Porosity and Permeability in Cores of Kangan and Dalan formations of Tabnak field
 
Tabnak Field is located in sub-coastal Fars province, north of Gavbandi town.Like most of other fields in the area, the reaervoir in this field is Dehramgroup where the contained hydrovarbon is gas . 
The results of macroscopic and microscopic studies and RCAL by Research Institute of Petroleum Industry (RIPI) of Dalan and Kangan formations show that porosity in Kangan is higher than in Dalan Formation (in the cored intervals) whereas Dalan has higher permeability than Kangan Formation. Shoal facies of Kangan has the highest porosity and permeability and the best reservoir quality , but in the Dalan Formation, tidal flat facies has highest porosity and permeability and the best reservoir quality due to intercrystaline porosity generated the by dolomitization.
Porosity type of Kangan Reservoir (oolithic facies of shoal facies belt in zone Ka-2) is isolated moldic and vuggy porosities that generate high porosity and low permeability values in this formation but in some intervals, channel and fracture porosities connect the isolated moldic and vuggy porosities and cause higher permeabilities.
Tidal flat facies of the Dalan Formation has high porosity and permeability and good reservoir quality but porosity, permeability and reservoir quality in tidal flat facies of Kangan formation is low .  because the effect of dolomitization in tidal flat facies of Dalan is more than in the Kangan Formation, so the  Dalan Formation in tidal flat facies has this is larger size dolomites (dolomicrosparite to dolosparite) and more intercrystalline porosity than the Kangan formation.
Generally, in the upper Dalan member of Tabnak Field, porosity increases from North west to South east due to a dolomitization increment .