Mountain Top University Library

ABSTRACT
On two occasions, the pipe conveying gas along Lagos - Ibadan expressway has been damaged
by the construction crew at the Mowe to Wawa axis corridor of the road which shows that there is
no knowledge of the location of the buried pipe. This research was therefore carried out at the
frontage of Mountain Top University main gate to provide information about the location and
depth of the gas pipeline using integrated geophysical approach comprising Ground Penetrating
radar (GPR), 2D Electrical Resistivity Imaging (ERI), Magnetic and Gravity methods. The gas
pipe was characterised by hyperbolic signature on the 2D GPR sections. Low magnetic
susceptibility was observed across the magnetic profiles. The pipe was characterised by high
bouguer anomaly on the gravity map and relatively high electrical resistivity signatures on the 2D
ERT methods. The anomalies associated with the pipe on each of the geophysical methods was
contoured and plotted on the map of the area from which the path of the pipe has been deduced
and all the geophysical methods have shown same alignment. GPR and 2D ERT methods have
delineated the pipe at depth range of 0.4 m to 2.76 m and 0.4 m to 2.2 m respectively across the
investigated area. Magnetic and gravity methods mapped the pipe at a depth range of 0.5 m to 2.9
m and 0.3 m to 1 m respectively. It can be concluded that all the geophysical methods have mapped
the pipe with diagnostic response where the depth of burial of the pipe is relatively shallow.
However, the sensitivity of gravity method to the pipe diminishes with increasing overburden
which can be observed on the 2D ERT due to poor resolution at depth. Geophysical survey should
be carried out in order to generate maps of buried utilities along proposed expansion so that future
damages can be averted.