Fault Beneath Paved Surface - SubSurface Instruments PL-VF10 User Manual

A potential problem could exist if a fault should lie beneath a paved surface. In this case, the a-f
will be used in the dirt at the side of the paved area. Since the return current in the soil begins its
return from the fault - like the spokes of a wheel laying on the ground - equal amounts of current will
enter the Grp if it is placed on the ground and positioned broadside to the fault. At the point where
the directional indication changes the fault will lie on a straight line projected at a right angle from the
center of the Grp.
The Grp adjustments can be made by slightly rotating the a-f
The operator should record this line over the paved area. By repeating this procedure from another
location near the paved area, another line will be produced. The intersection of the two lines is the
location of the fault.
GROUND RETURN PROBE IS
POSITIONED FOR A MINIMUM
(NULL) RECEIVER DISPLAY.
28
SERIES
f b p
aults eneath aved
PAVED ROAD
SHEATH-TO-GROUND
s
urfaCes
rame
FAULT
to find the directional change.
CABLE
GROUND RETURN PROBE IS
POSITIONED FOR A MINIMUM
(NULL) RECEIVER DISPLAY.
www.ssilocators.com
rame