Next Earthquake

Suva Can Expect

200 Years From Now

A REPORT issued jointly by Dr.

W. Skiba, Senior Geologist in Fiji, and Mr. H. Wellman, a New Zealand expert on tectonic (non-volcanic) earthquakes, shows that there is no evidence to support the theory that Fiji’s September earthquake was of volcanic origin.

Soundings of Suva Harbour and its approaches to a depth of 2,000 feet showed no traces of recent eruption; but they did indicate that a considerable underwater land slide had taken place. In one place

the depth has increased by about 300 feet and in another it has decreased by the same amount. Many thous ands of tons of material were in volved, and this movement was probably responsible for the tsunami, or so-called “tidal” wave (though the tide is in no way involved) rather than the actual earthquake itself.

Extensive cracks along and parallel with the coral reefs off shore near Suva have been ex amined. The parts of the reef sea ward of the cracks have tilted sea ward and numerous very large blocks of coral have been thrown onto the reef.

The report emphasises that the recent earthquake was not an

isolated event. Earthquakes of similar intensity have occurred in Fiji several times during the last 100 years. A list of these is being prepared.

On the basis of evidence at pre sent available of past earthquakes, it seems likely that a similar shake might occur at intervals of approxi mately 20 years, and within the Suva area at intervals of possibly 200 years.

The report explains one occur rence that gave ground to the sug gestion that the earthquake was of volcanic origin. During the shake, sand-saturated water spouted from the ground on the alluvial flats of Ba, Wainibokasi, Vunidawa and Navua. They were caused through compaction—as the surface soil settled onto the less compact, water saturated stratum below.

A full technical bulletin on the earthquake will shortly be issued by the Geological Survey Department.

Seismic Reporting Stations

As Warning

Meanwhile, Mr. J. C. Grover, BSIP Government geologist, visit ing Suva during October, advocated the setting up of a Pacific-wide net work of seismic reporting stations to give advance warning of tsunami waves which sometimes cause great damage at points thousands of miles from their point of origin.

Though no such damage seems to have resulted from the recent earthquake in the Suva region, there have been several cases in recent years where damage has occurred. One which originated from a submarine earthquake near Alaska, did damage in Hawaii, the Marquesas and Tahiti several years ago.

Though the waves travel at great speed, an efficient organisation could, in many cases, pass a warning in time for people to gain higja ground before the wave arrived.

It was reported to the Fiji Legis lative Council at the end of Sep tember that the nett amount raised in the Colony’s internal Develop ment Loan was £1,243,334. The amount has been transferred to the Development Reserve Fund.