Petrophysical modelling of the Cretaceous Lower Goru Formation, Lower Indus Basin, Pakistan
Keywords:
Petrophysical modelling; Hydrocarbon; Reservoir characterization; Cretaceous; Goru Formation; Lower Indus BasinAbstract
In this paper, a comprehensive petrophysical investigation of the Cretaceous Lower Goru Formation in
six wells of Sawan Gas Field was made. For this purpose, the clay volume, types of porosities, qualitative
permeability, hydrocarbon and water saturation, movable hydrocarbon index, bulk volume of water, and
dominant lithology were assessed. On the basis of these petrophysical parameters, two hydrocarbons bearing
zones were identified in studied reservoir. The zone-01 having considerable thickness with good reservoir
characteristics in all wells with estimated gas in place of 223124813.6 cf while zone-02 has good reservoir
characteristics only in Sawan-07 and -08 wells with estimated gas in place of 53471927.4 cf. The proposed
stratigraphic model of reservoir levels showed the pinching of pay zones towards NE of the field. This
pinching of the pay zones towards NE can be attributed to the lateral facies changes triggered by sea level
fluctuations.
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