ABEM Terrameter SAS 1000 / SAS 4000
- 109 -
14.16
POLDIP_A AND POLDIP_O: 4 CHANNEL POLE-DIPOLE 2D TO
3D SURVEYING
X axis
Y
a
x
is
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Start
End
Start
End
Start
End
Start
End
Start
End
Start
End
Start
End
Start
End
Start
End
These protocol files are intended for area cover via a number of 2D sections that are
combined into a 3D data set (see “3D Resistivity Surveying by Means of a Number of 2D
Layouts” on page 43), using Terrameter SAS4000 and ES10-64. Measurements can be taken
with cable layout in one direction only, as indicated in the sketch above, or by adding
perpendicular layout measurements as well. One remote electrode is required at a distance of
preferably at least 10 times the maximum electrode separation. It is recommended not to
exceed line separations of more than twice the electrode spacing.
The POLDIP_O only contains the measurement combinations with odd n-factors, forward and
reverse, whereas the POLDIP_A protocol contains both odd and even measurement
combinations. The former is thus much faster to measure.
Protocol
Array Type
Address File
Size .ORG
Size .UP/.DWN
POLDIP_O
Pole-dipole
ONECABLE
206
-
POLDIP_A
Pole-dipole
ONECABLE
394
-
These protocol files are provided as an example, and similar protocols for other electrode
arrays can be used as well. One advantage of the pole-dipole array is good depth penetration
and good data cover near the ends of the layout, which is important when operating in
confined spaces. Dipole-dipole and/or multiple gradient array protocols are recommend if it is
practical to avoid using a remote electrode.
