Seismic Observations of Fiji
Mr.BOLA Epeli Sese M R (2011Global Seismological Observation Course)
Mineral Resources Department, Fiji
1. National Seismic Network
Seismograph stations have been operating in Fiji since 1913 but were used by a number oforganizations for geological research. Mineral Resources Department started its monitoring using
seismographs in 1976, following the installation of the two stations in Vunikawai and Suva.
In 1980 the first seismograph network was established, in the installation of seventeen
seismograph stations. These stations then became inactive in the late 90’s because of the difficulty
in searching for spare parts which has become phased out and also the high maintenance cost ofthese stations.
In 2003, the VHF system was replaced by the VSAT telemetry system in which it consists of 3stations distributed across Fiji. The introduction of the VSAT monitoring system marks the changeof analogue data to digital. The 3 station network then started to face problems in terms of powerand construction failures and also technical support. This leads to the upgrading projects for thenetwork in 2006. The upgrade involves the relocation of some of the existing stations, new VSAT
transmission equipments, technical training, new hypocenter auto locating software, earthquake
email notifications and change of the satellite band from Ku to C and the installation of the 3
additional stations.
Currently the network consists of 6 VSAT and 2 VHF stations. The upgrade has reallyextended the monitoring capacity of the Fiji network and also contributes to the rapidness of thedissemination of earthquake information and bulletin to the general public and relevantorganizations.
2. Fiji Network Upgrade
The Seismology Section’s through JICA funding and assistance has recently upgraded the Fiji
Seismic Network, in which 3 additional stations named Lakeba, Dogotuki and Tailevu were added
to the network. The upgrading works also includes the joint seismic network between Fiji andTonga. This allows the Fiji observatory to have access to the Tonga observatory data and vice versa
for accurate determination of earthquake hypocenters between the two regions. To eliminate
problems faced by the existing stations, the Taveuni, Kadavu and Yasawa station were relocated.
Gel batteries were purchased to replace the normal batteries and additional solar panels wereinstalled. Broadband seismometers replace the short period sensors. These joint network operations
involved a change in the satellite band used by the Fiji network, from Ku to C-band (TongaNetwork satellite band) Also new software were introduced to autolocate events and also to provide
us with earthquake information. Training were being conducted by engineer from Nanometrics andalso technical expert from JICA in terms of vsat peripherals installation and seismic data analysis.

Tremendous efforts have been carried out by the technical expert from Nanometrics in Canada,
JICA experts together with technical officers, Seismology Section, Fiji.
3. Upgrade Outcome
The upgrade has been a great benefit to the Fiji monitoring system as it now has a stable network
and also the enhancing of earthquake monitoring and analysis. Fiji’ access to data provided by theTonga stations and vice versa.

Figure 1. National seismic network and the Tonga Seismic Network