Geology Reference
In-Depth Information
Figure 5.5
Variation in skin depth,
d
, with frequency,
f
, resistivity,
ρ
, and
conductivity,
σ
.
is much smaller than the skin depth, the separation is the dominant factor
controlling depth penetration.
The higher the frequency, the more precisely small targets will be lo-
cated and resolved, but the skin-depth equation shows that penetration is
reduced at higher frequencies. In CW surveys, additional information can
be obtained by using two or more frequencies. TEM surveys are inherently
multi-frequency.
