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Oil and gas saturation ratio (K og) affects on the indications
of many geophysical methods. Most close relationship K og have
with electrical resistance of rocks. Increased values K og leads to
increased electrical resistance (Fig. 3.7, a), with all other constant
factors.

а) б)

п P н
10000 10000
1000 1000

100 100
10 10
1
0 20 40 60 80 100 K ,% 0 20 40 60 80 100 K ,%
нг
нг
Figure 3.7 - Dependence ρ r(a) and P p(b) from K og

In order to avoid exposure on layer electrical resistance
other factors, except K og use relative value of the layer resistance
with any K og the resistance of the layer when K o = 0% and K w =
100%, ie the resistance of the aquifer. This ratio is called the
relative saturation parameter:

P  l  1, (3.6)
p

wl

where: ρ l – layer resistance with an unknown K og, with defined
according LL, L, IL; ρ wl - resistance of the layer when K w = 100%.
Resistance aquifer ρ wl in expression P p can be determined
through the porosity parameter:

  pz
P  wl  , (3.7)
p
   q  Q
w f

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