356 S. G. KoMAROv and Z. I. Keivsar 



difiference x is equal to unity. For three, two and one determination the 

 weight of the difference x is equal to 0.86, 0.71 and 0.5 respectively. 



In all the wells for a given stratum, according to the obtained differences 

 x-j., x^, •■■,x^, in the values of the permeability, found from the specific 

 resistance and cores, and the weights of these differences P^, P2, ...,P„, 

 each of which has one of the above four values, the following calculations 

 were made (") : 



(a) the mean error in a separate determination 



_ %°i + ^2 °2 + • • • + x^Pn ^ /--v 



"^ P, + P, + ...+P, ' ^""^ 



(b) the mean square error of a separate determination 



[/ ni + 0.8( 



~t~ ^2 -^2 ~l" • • • + ^fi Pn 



86n. + 0.71/IO + 0.5/14 - 1 ' 



(7) 



where n-^, n2, n^, n^ are the numbers of wells in which the difference x has 

 the weight of 1.0; 0.86, 0.71, 0.5 respectively. 



The error was expressed in millidarcies and relative units in percentages 

 with respect to the value K^^^. 



As can be seen from Table 1, the error in the determination of perme- 

 ability from the specific resistance is rather high, being 170-200 milhdarcies or 

 about 50%. This indicates the presence of errors in the method for determin- 

 ing the permeability by the specific resistance or the insufficiently close 

 connection between the residual water saturation and permeability. 



The strata are characterized by a comparatively high degree of homoge- 

 neity: the permeabiHty /L^g^obtained from the cores from separate wells 

 is close to the average value for the permeabiHty for the stratum as a whole. 

 In connection with this, determinations were made of: 



(a) The actual mean permeability of the stratum 



j^k ^K^P^ + K^P^+^^^ + K^^ 



'^'"- P, + P2+... + Pn ' 



where K![, K^, •••, Kn ^^^ ^^^^ values for the permeability of the stratum, 

 obtained from cores for separate wells; P-^, P^, •••,Pn the weights of the 

 separate values of the permeability taken for four or more, three, two and 

 one determination respectively equal to 1, 0.86, 0.71 and 0.5; 



(b) K\-K^^^,K\-K^^, ...,/C;-ir^„are the deviations of the values for 

 the permeability of the stratum obtained from the cores of separate wells, 

 from the actual mean value of the permeability for the stratum K^^', 



