Page 109 - Reservoir Formation Damage

92 Reservoir Formation Damage

exp
(5-64)
expG -1

In view of the Gruesbeck and Collins (1982) plugging and nonplugging
pathways approach, Civan (2000) concluded that the E coefficient can
be analogous to the fraction of the nonplugging pathways and Eqs. 5-63
and 64 can be attributed to the nonplugging and plugging pathways in
porous media, respectively.

Multi-Parameter Regression Models

Efforts for development of empirical correlations and theoretical
models for prediction of the permeability of porous media are being
pursued by many investigators because the applications of the theoretical
models in the formation damage prediction have had limited success.
Because of their inherent simplifications, these models are not able to
represent the complicated nature of the relationship of the permeability
to the petrographical, petrophysical, and mineralogical parameters of
geological porous materials. Empirical models, such as by Nolen et al.
(1992) have been shown to incorporate such parameters to accurately
predict permeability. However, the mathematical form of such models
varied in the literature. Extending the Nolen et al. approach, Civan (1996)
proposed two general empirical correlations:

(5-65)

(5-66)

in which x i:i = l,2,...,m represent the various petrographical, petro-
physical, and mineralogical variables, and b and a,-:/ = l,2,...,m are
empirically determined parameters.

Network Models

Network models facilitate representations of porous media by pre-
scribed networks of nodes (pore bodies) connected with bonds (pore
throats). Network models have been used by many researchers, including