TARANAKI OIL

Marlborough Express, Volume XLVII, Issue 143, 19 June 1913, Page 2

TARANAKI OIL

ORIGIN OF THE DEPOSITS

INTERESTING SPECULATIONS BY A SCIENTIST.

Before the last meeting of the Canterbury Philosophical Institute Mr It. Speight gave an interesting address" on the origin of the petroleum deposits recently located in Tan-anaki. Mr Speight said that although bores had only been sunk over an area of a few acres at Moturoa, near New 1 lymouth, it was known that hundreds of square miles in Tarariaki were petroliferous.

NOT OF VOLCANIC ORIGIN

Apart from the actual surface appearance of petroleum in the rocks at Moturoa, there was circumstantial evidence of a, petroleum deposit over an area of country tlrreo miles wide and thirty miles long, running south-east from New Plymouth." Over the whole of this area gas emanations were met .with, and might be taken as ia.n indication that petroleum was extremely likely to exist in the measures below. The existence of oil shale, also, was presumptive evidence of the existence of oil deposits. The lecturer said that he was not inclined to believe that the soil on these fields was of volcanic origin. No volcanic rock had been met with in the borings at Moturoa, and it might be presumed that the rock at Moturoa, like the rock at Patritutu, was not of volcanic origin, althougjh it was located in the midst of the. area of volcanic debris surrounding Mount Egmont. DIFFERENT THEORIES.

He reviewed briefly the various leading theories regarding the origin of petroleum, including the theory of Sir James Hector, who considered that petroleum bad its source in the action of volcanic rocks1, and the theory that the oil was the produce of an organic origin, he said, was supported by the presence of sulphur and of nitrogen, in many of the world's oil deposits; but it was difficult to explain how such enormous quantities of the oil could be found in a comparatively small area. There might, however, have been conditions which would have brought about a. vast deposit of ianimal matter. The floor of the Black Sea, for instance, was covered for a depth of many feet with decaying or partially decaying animal matter. The Black Sea was of comparatively recent formation, and was connected with the' Mediterranean only by one shallow strait. It had no deep scavengers to absorb the dead fish that fell from the upper waters. It wasi necessary where the conditions precedent to th© formation of an oil deposit, whatever they were, had been fulfilled, that something would take place, to trap the oil and protect it. Oil was found most frequently in America in places where the urjper strata- of the earth's crust had*been pushed upward and bent, leaving a hollow under thei crown of the upheaval, in which the oil accumulated. The cause of such upheavals was in most instances probably the rising up of a volcanic plug. This was almost 'certainly the case with the oil deposits in Mexico.

TARANAKI OIL OF MARINE

ORIGIN

The conditions in the neighborhood of New Plymouth were entirely favorable to the conservation of petroleum, and the probabilities were that the petroleum had its origin in decomposed marine and animal matter: The papa formation which abounded in the district was' full of organic matter, and an analysis of the brine found in the rocks bore out the general assumption of a marine origin. The brine was m many ways dissimilar to sea brine, but its constituents suggested a marine origin.