THE EARTHQUAKE WAVE

Hawke's Bay Herald, Volume 12, Issue 975, 5 September 1868, Page 3

THE EARTHQUAKE WAVE

To the Editor of the "Lyttelton Times."

Sir, — When I took the liberty of addressing to you a letter on the 15th of this month, in reference to earthquake waves in the sea, I was not aware that in the South. Pacific Ocean, and much nearer to us than the Sandwich Islands, submarine volcanic eruptions of great violence had lately taken place.

I learnt this fact only a few days ago, from Ly ell's new edition of the Principles of Geology, vol. 11., page 409, which arrived in New Zealand by one of the late mails ; and as its account will be doubtless of great interest to many of your readers, I send you a verbal extract of the paragraph in question : — " Even in the present year, Nov. 1867, a submarine volcano has burst out in the South Pacific, at a point 1200 geographical miles from New Zealand, and 1800 from Australia, between two of the most easterly islands of the Samoa or Navigator's group, an archipelago where there had been no tradition of an eruption within the memory of man. This outburst was preceded by numerous shocks of earthquakes. Jets of mud and dense columns of sand and stones rising 2000 feet, and the fearful crash of masses of rock hurled upwards, and coming in collision with each, other, which, were falling, attested the great volume of ejected matter, which accumulated in the bed of the ocean, although there was no permanent protrusion of a new volcano above its level." The earthquake felt at sea by the ship Rose of Australia, on June 27, of this year, when among the Kermadec group, of which your paper gave an account, may probably be traced to the same submarine volcanic vent, from which the Kermadec Islands are situated in a south by west direction, and at a distance of about 1000 geographical miles. In looking at a map of the Pacific Ocean, you will observe that the Sandwich Islands, a very active volcanic region, lie in a N.N.E. direction from Banks Peninsula, and, what is very striking, that just half-way between the former and that long extinct volcanic centre in this island, and in the very same direction, we find the spot' in the Samoa group in which, according to the account given by Sir Charles Lyell, a new volcano is just forming. This curious fact might give rise to fear, or to the unpleasant anticipation that the next volcanic outbreak might be in Banks Peninsula, and I may, therefore, be allowed to state what scientific research in many parts of the world have taught us in this respect. Should any volcanic eruptions take place in New Zealand at some future day, it will certainly not be in Banks Peninsula, as experience has already sufficiently shewn us that any volcanic system of tertiary age, and extinct without doubt : for many' thousands, if not hundreds of thousands of years, will never become active again. The reason for such non-occurrence is simply that the fissures formed originally in the earth's crust below such a former volcanic vent have already become so effectually filled up by hard volcanic rocks during numberless eruptions, and the sides near these fissures so much strengthened by tlie same agency, that subterranean disturbances near that locality will seek an outlet at any weaker spot at a distance. This interesting subject might induce me to offer some more generalisations did I not fear that my letter would almost take the form of a geological lecture, whicli I wish to avoid. — I am &c, Julius Haast. Cliristclmrch, Aug. 25, 1868.