The Wellington earthquake could have brought a lot of damage, but the possibility of bigger aftershocks remains high, according to scientists.

The fault line that caused the earthquakes in Cook Strait has long been known to produce earthquake "swarms" but none have been recorded as devastating, according to historical records.

The Wellington quakes that occurred three times on Friday, July 19, and twice on July 21 and the following aftershocks were due to city's plates moving between the Pacific and Australian tectonic plates. The highest magnitude of an earthquake in Wellington was recorded last night at 6.5.

Dr. Richard Sharpe, Director of Earthquake Engineering at Beca said he did not expect the yesterday's quakes at Wellington will cause damage to buildings. However, Mr. Sharpe said the quakes would prompt the city to conduct engineering checks.

New Zealand is resilient to earthquakes in general. According to Mr. Sharpe, other countries that will experience the same type of earthquakes in Wellington will probably cause very brittle buildings to sustain damage.

Professor of Geophysics at Victoria University Euan Smith said that the interface between the underlying Pacific plates and overlying Australian plates was a critical fault. Mr. Smith said the same fault could potentially cause massive earthquakes.

Historical records in New Zealand have no recent and equivalent record of big earthquakes for hundreds of years. Geologists don't have a gauge to determine how often big earthquakes can occur.

Mr. Smith also said residents in New Zealand have a valid reason to be concerned since severe earthquakes can be unpredictable. The latest seismic activities were similar to a swarm of smaller earthquakes which occurred in Wellington in January 1950.

The 30 earthquakes in 1950 had a magnitude of 3 and also occurred in Cook Strait. The previous location of quakes was only 50 kilometres from the current earthquake's epicentre.

Mr. Smith said the recent swarm of earthquakes in Wellington could go on for a month like what happened in 1950 or there would be no more quakes. However, Mr. Smith said this could be very unlikely.

A massive earthquake could not be ruled out due since seismic activities were unpredictable. Mr. Smith noted that there is a 10 per cent chance of this happening in the future. If the Wellington earthquakes would have directly hit the city, there would have been significant damage.

Mr. Smith said the recent earthquakes in Wellington were smaller in comparison to the earthquake in Christchurch in February 22.

New Zealand residents are advised to secure anything that could cause injury or damage in case of a big earthquake.

RELATED STORIES