 |
THE MURCHISON EARTHQUAKE |
 |
|
THE MURCHISON EARTHQUAKE |
|
In Auckland, the shaking was less severe, but it lasted for more than a minute. The question in everyone's mind was where was the centre of the earthquake?
The seismological equipment available at the time was very primitive and press reports were sketchy because many of the telegraph lines in the South Island had broken down.
Later seismographs of the aftershocks indicated that the centre of the quake was in the Buller district inland from Westport. A geological team from Wellington immediately caught the ferry for Nelson.
A telegraph lines were repaired, it became apparent that both Nelson and Westport had been seriously affected.
The tower of Nelson College had collapsed and masonry had fallen through the roof of dormitories, which fortunately were not occupied at the time. Many chimneys and parapets had fallen in the town and plate glass shop windows had shattered.
In Greymouth, hardly a chimney was left standing and gas, water and sewage pipes had burst beneath the ground. Railway lines had twisted and the roofs of several coal mines had collapsed. Luckily all of the miners had managed to escape.
News finally came through from Westport when the collier, Kaitoke, managed to get its radio working. The Post Office had collapsed during the earthquake, cutting off all telegraph lines.
A number of other buildings were also badly damaged and many people were camping outside their houses as aftershocks continued to hit the region, accompanied by an eerie rumbling sound.
Eventually it was realised that the centre of the quake was located inland near the tiny settlement of Murchison. This is an area of rugged mountains and deep river valleys, where granite and sandstone cliffs rise up to 1,200 metres above the valley floors.
Murchison was the largest settlement in the region, with a population of approximately 3000 people at that time. It consisted of a Post Office, a bank, a school, two hotels and a few stores, as well as a collection of wooden houses.
It was located on a flat area near the junction of the Matiri, the Matakitaki, the Mangles, and the Buller rivers.
The Murchison earthquake was the most severe ever measured in New Zealand up to that time, although the 1865 Wairarapa Earthquake, which wasn't measured on seismological equipment, is thought to have been even more powerful.
On The Richter magnitude scale, which records the volume of energy involved in the whole event, the Murchison earthquake recorded a magnitude of 7.8.
According to the Modified Mercalli scale, which rates shocks on a scale from one to twelve, the Murchison Earthquake reached a severity level of 11 at its centre, and reached 5 as far away as Hamilton.
One of the unusual features of the earthquake was the extremely loud noise it produced, possibly caused by the deep narrow valleys at its centre.
The sound of the initial shock was heard as far away as New Plymouth and the aftershocks continued to rumble like thunder for several weeks after the main quake.
Seventeen people lost their lives in the Murchison earthquake. Ten were killed in the town and other seven lost their lives in the outlining districts.
However, the loss of life from such a powerful earthquake in a more densely populated region would have been many times greater and the damage to property immense. As it was, it took many weeks to repair the damage to the town and restore essential services.
The Murchison earthquake had a major effect on the environment in the region and a great deal of the landscape in the Buller district was changed considerably.
The land on one side of the faultline was uplifted so much that it formed a cliff up to five metes in height. At one place where it crossed the Maruia River, a new waterfall was created. Several rivers changed their courses and vast sections of 
cliffs and mountainsides fell away in huge landslips which scarred the countryside.
In many ways the Murchison earthquake was a grim warning of what might happen if an equally severe earthquake was to strike a more densely populated area, as was to occur at Napier less than two years later!