Page 161 - Standard Handbook Petroleum Natural Gas Engineering VOLUME2

130 Reservoir Engineering

EABLE

FILE
31
.----Icp-ukulm----
0.0 100.0
SFLACOHHI4 )
0.0 100.0
CILD(I4H /M>
400.0 0.0
Figure 5-74. Examples of an SP log through an impermeable and a
permeable zone.

Theory Nonfocused (Normal Tools.) The first tools to be used were nonfocused
tools [58]. The electrode arrangement is as Shown in Figure 5-75a [58]. As shown
earlier, resistivity, R, is found using Ohm’s Law (r = V/I):

rA
R=- (544)
L
where V = voltage read from meter
I = current read from meter
A = surface area, m2
L = length, m
R = resistivity, ohm-m
r = resistance, ohms
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