THE EARTHQUAKE

Ashburton Guardian, Volume VII, Issue 1934, 3 September 1888, Page 2

THE EARTHQUAKE

♦ There Is little to add to what we published on Saturday as to the effeots of the eirthquike throughout the southern end central parts of New Zealand. The efleot seems to have been more violent In Christ* church, Kaikoura, and the West Coast. The true direction of the ground swell waa from northeast to south-west. The ChrCstohuroh people have to mourn the loss of their fine Cathedral spire, and from reports to band It would seem that Ohrlstohoroh haa suffered more damage than any other town visited by the earthquake. The shuck of earthquake felt m 1869 by the OhrUtohure > people was more severe, but less damage waa done then. During an earth tremor In 1881 part of the stone work of the Cathedral spire oame down, but now about 30 feat of it has disappeared, and much more haa been loosened. The earthquake does not seem to have been felt north of New Plymouth or even at Napier. Inveroarglll Is the moat lonthernmost town from which details regarding the shock are to band. Between New Plymouth and Invercjrgill the shook seems to have been/^general though m the part of the North Island touched by the wave the ef&ot was very slight. Our Alford ForesttfSrreepondeafc says: —Mr J. b'poor's chimney was cracked by the earthquake. #c is one of the new village settlers. .-

Profes£of Button, of Ohrlstohuroh, •P*g on earthquakes generally, says:— There haa been no Bjatematio investigation of any kiad, made by the Govern* merit, of earthquakes m this colony, and no/facts have been placed on record except tjko dates of their occurrence. If there r 'are instruments ia Wellington, there has been no notice taken of them, nor is there any published record of the results obtained by them To investigate earth* quakes it is neceearry to have instruments m no less than three different plaoes, then some idea of the position- of the centre of dietuabanoe could be made out ; it would not be left to guesswork ; and we ', should then be able to gain the necessary | information as to the size of the earth- , quake wave ci well as its direction, i ", me. practical advantage of this infor- , mation is that builders and architects can, i by knowing the direction the earthquake , takeß, adopt precautionary measures m l adapting their buildings bo as te turn the ' strong side m that direction. Beautiful Instruments are now being made m the ■ Cambridge University which record all necessary data oonneoted with an earth--1 quake — time observation*, and earth • movement of all descriptions. Thesa work automatically. In the interest of noience 1 and the colonist generally, theße Bhould | be supplied, and Wellington, Nelson aud , Ohrif tchurch, are suitable places to procure the data, as there are plenty of people at each of these centres who oould . be found willing to attecd to them. I **As f« •» oan be gleaned from the prjbi Uahed data, there are three principal i seismlo regions In New Zealand. One , has Its centre m Cook's Strtffc, and the esrthquakea range between Taranakl and Wa *' a ' a P a OQ the North, nod southward ■ to Ohrlstohuroh and Hokhika. These are , the largea- m New Zealand. In this area there are blbo several minor independent regions, of whloh Banka' Penlnaulalaone The second is that known as the Hot L Lake regloo of the North Island, from , r.aranga and the Walkato on the North. , to Taupo and Napier on the South. In i this region the olroumstanoes are quite different. There are a great number of • ameller earthquakes, which are more 1 SIPt 1 , « and »ie not felt so far. The - third ia Southern Otago. 1,, thia region [ earthpuakaa are felt from Dunedln and neighborhood tp the extreme Souih of the Jaland. They are neither common nor heavy. '' j The Professor also says :— Telegrams i snow that the earlhqaake of Batord*y 1 morning did not originate In Banks' t Feniosalo, as I at firat thonuht probable, ; but aomewhere to the West, probably In ; Inangahua County. I Infer this from the , 'times at which the earthquake ooourred at ; different phoea— Brat at Greymouth and , Weatport, then at Timtru, Ohrlatohurch, Wellington aud Nelson, and last atlnver- > oarglll, Dunedln, and New Plymouth. » The shook was felt over a radius of three hundred miles from the centre of dls- ; turbanoo, and It Is remarkable., that a shook so widely extended should have , done so little damage. .-This w»a probably ; due to. tke centre of dlaturbanoo lying deep down In the ea»th, so that the earthwave at the surface was more vertioal than usual, Aitothe.' remarkable oiroomstanoe is the extraordinary rapidity with which the earthquake eqread over the surface of the earth, travelling at a rate of about a mile In a second, whioh is from four to five times faster than the observed velocity of transit of earth waves through the ground This again cm only be accounted fqr by supposing that the centre of oUati&rbanoe was very deeply seated. Btfct ll^w.e take the actual velooity e$ transit o£ the wave through the earjE to. have been 1200fi per (jeoond, y^hlch Is the average of recorded observations, calculation shows that In order to get an apparent surface velooity of fourteen er fifteen miles a sepond, f^r from 100 to 800 miles, the centra of dlaturhanoa would have to be several hundreda of miles below the surface, which is quite Incredible. Of course time obaetvatlona alone, even If made with the greatest acouraoy, are only capable of giving the roughest approximation to the position of the centre of disturbance j bat it is evident there is soraethtog wrong, either m reoorded, qhaeirvatlonß, or else In our Ideas of the Interior of the earth, and it is very desirable that accurate Instrumental ob« sarvatlons of our earthquake pheDonxenax ahoold be recorded In at least ft^Q, or alx plbobb In New Zealand, The selßmogr^nh, t»» the Wellington Mußeura spjOroft to lie the only one In the oolony, and this appears to register the horizontal dlreotlon ot the wave ooly, whloh Is not sufficient to determine the foous of an earthquake. Exoellenr automatic self-registering seismographs, capable of recording all necessary earthquake phenomena, oan be Fobtalned m England for about £60 eaoh, and a*f intelligent person could be tatight how to use them. But I have written so often In vain about the lmnpatanee of studying our earth* quakes, that I despair of the Government taking any effectual stops In the majtter^