Table 4: The WBM used to drill through Gachsaran Formation (Members 1 – 6) in cased well (mud type: heavy-weight salt-saturated WBM).

Component Concentration (Kg / m3)
Water As the base of mud
Soda ash 4.3 kg/m3
Salt(NaCl) 357 kg/m3
Starch(modified) 40 kg/m3
Barite (barium sulfate)+ Fer-o-bar (ferric oxide) 3 portion barite + 1 portion ferobar adding to get requirement density from 2.08(gr/cm3) at start, to 2.40(gr/cm3)at finale hole drilling
Caustic soda(NaOH) 0.28 kg/m3
Natural Gum 11 kg/m3