Geology Map of Viti Levu \(scale 1:50,000\) - WHYCOS

Electro-Magnetic Survey
around Fiji Islands.
By
Jonati Railala

Electro-Magnetic Survey
around Fiji islands
•Electro-Magnetic survey is
considered to be important in
locating possible drillsite for
Groundwater Resources.
•Many of the production boreholes
drilled around Fiji Islands were located
by using this EM 34 survey.

Geology Map of Viti Levu
(scale 1:50,000)

Tavua Geology Mapsheet

EM Survey on Makuluva
• The equipment operates
at three different
frequencies and coil
spacing, providing three
different effective
exploration depths.
• The instrument is capable
of 60m exploration depth
using a horizontal coil
configuration a 40m coil
spacing.

EM survey on Makuluva Is
• The horizontal coil
configuration is not
appropriate for use in
high conductivity
areas ( e.g. Makuluva
Island)
• Due to the high
conductivity values
the instrument will not
responses ( out of
scale)

Some of EM survey data being interpreted
Seaqaqa line 2 (20 m spacing)
Hz
Vz
80
Possible drillsite
70
60
50
40
30
20
distance
60
Seaqaqa line 2 (40 m spacing)
Possible drillsite
Hz
Vz
50
40
30
20
10
0
distance (m)

Reliable data compilation and
interpretation will result an viable
production borehole.

Vinaka Vakalevu
Mamaste
Moce Mada