Comparison and Validation of the Modified Kozeny-Carman correlation for the estimation of permeability

Permeability of the rock can only be measure directly by performing RCAL/SCAL (Routine/Special Core Analysis) on core samples, which have to be captured and retrieved while drilling the well representing a variety of challenges. In this study the modified Kozeny-Carman correlation (Nooruddin and Hossain, 2011) has been studied in order to establish the accuracy of the permeability estimations. The variables involved within the correlation – shape factor (fg), specific surface area of the grain (SVgr), lithology factor (a) and cementation exponent (m) – are proved to represent the porous system. Two data sets were used to validate the accuracy of the correlation. Data set 1 has a very poor permeability-porosity relationship, with very low porosity values which inferred a lot of noise in the permeability results. Data set 2 has a good permeability-porosity relationship, and the grain size analysis report was useful to estimate pore throat radius (r) and consequently SVgr. a and m values were taken from the literature due to lack of SCAL data. Permeability data estimated by using the modified Kozeny-Carman correlation proved to be in agreement with RCAL permeability; however, it is very important to calibrate those measurements back to core analysis or reservoir rock measurements.