resistivity index | Energy Glossary

Energy Glossary

Explore the Energy Glossary

Look up terms beginning with:

#
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z

resistivity index

1. n. [Formation Evaluation]

The ratio of the true resistivity to the resistivity of the same rock filled with water. The resistivity index can be expressed as I = R_t / R_o, where R_o is the water filled resistivity and R_t is the true resistivity. It is related to the water saturation by the saturation exponent, n (I = S_w^-n), and is a key component of the Archie equation.