THE PERMEABILITY OF OIL-BEARING STRATA 



373 



4. Starting from erroneous notions on the high accuracy of determining 

 permeabihty from the specific resistance of the Devonian sandstone, incorrect 

 conclusions were drawn as to the most favourable possibilities of this method 

 for the Devonian sandstones in comparison with other sediments. It is 

 obvious however, that the method for determining permeabihty from the 

 specific resistance in other deposits will give the same results as in the 

 Devonian sandstones, and that there is apparently no reason to limit the field 

 of application of the method. 



In any case, this problem should always be solved separately for each 

 stratum and independently of the type of deposit and the region. 



Kpj, m darcies 



Fig. 10. Curves for the dependence of the coefficient of residual water saturation 

 Kj. ^ on the permeability K^^j.. 1 — according to the Dolina curve (1 — curve from 

 Fig. 2); 2 — from the Dakhnov curve (2 — curve from Fig. 2); 3-7 from the empirical 

 curves of the dependence of Q on the permeability Kp^j. (Fig. 6) ; 3 — Tuimazinsk deposit, 

 stratum Dj; 4 — Tuimazinskian deposit, stratum -Dij, 5— Romashkinskian deposit, 

 stratum D^Yy ; 6 — Romashkinskian deposit, stratum D^^; 7 — Sokolovogorsk deposit, stra- 

 tum i)y ; 8 — from experimental data by Morozov, obtained from samples of the Devonian 

 sandstone (results of separate measurements are given by points); 9 — from the curves 

 of Morozov for porosity m = 0.2(^^). 



ESTABLISHING THE CONNECTION BETWEEN THE COEFFICIENT OF INCREASE 

 IN RESISTANCE AND THE PERMEABILITY 



To use the method of determining permeability from the specific resistance, 

 it is essential first of all to establish the connection between the interstitial 

 water saturation and the permeability. 



Fig. 9 gives some results on the interstitial water saturation of rocks of 



