PETROLEUM NEWS.

Taranaki Daily News, Volume LII, Issue 255, 3 December 1909, Page 4

PETROLEUM NEWS.

TWO RIVALS TO NEW PLYMOUTH. In two districts besides the wellknown New Plymouth oilfield efforts a v e being made to locate payable petroleum supplies in the Dominion. Those are dealt with in the annual report of the Government Geological Survey Department, which contains interesting relercnces to the geology of the Waitangi Hill district, near Gisborne, where the Gisborne Oil Company is now sinking a deep bore hole. Analysts of the «v' taken from the springs at Waitangi Hill show that the oil contains an average of over 40 per cent, of burning oiW and a large percentage of lubricating oils. On account of the moderately large percentage of burning oils the crude product is of special importance, since it can ill certain eases be used for heating purposes without any refinement.

"From the 'geological examination ot this subdivision, which has just been completed," continues' the report, "it would appear that the petroleum-bear-ing stratum is nowhere exposed at the surface. The petroleum showing on the springs i.s probably derived from a stratum considerably below the surface at this point, and makes its way to the surface by rising up a 'break' or faulty plane. The fact that the oil indications show on the same line for a distance of sixteen chains in itself suggests that they are on a line of fault. The depth at which the petroleum-bearing stratum occurs can only be a matter of speculation until some information as to the nature of the strata underlying the lowest bed exposed on the surface in the area examined has been obtained by deep boring. It is therefore essential for the future prospects of a petroleum industry for Poverty Bay that a full and true record should be kept of the operations now in progress." A very favorable report is' given by Mr. P. G. Morgan, general geologist, upon the possibility of the Kotuku oilfield, near Grcymouth. He believes that any shallow bore within this area will yield some oil, and often payable, or almost payable, results. As for the depth of the probable reservoir, in the Grcymouth Harbor Board's No. 3 bore at Dobson natural gas was encountered in the bore at a depth of 1747ffc. If the supposed coal measures at Kotuku have the same thickness as at Brunner, and were not denuded before the deposition of the Miocene beds, it is probable that the petroleum originates at a great depth, possibly 4000 ft or 5000 ft. Since, owing to water-pressure, oil tends to rise in the strata, the main oil reservoirs may be at any less depth. Again, since in all known oilfields of any importance petroleum has been encountered at varying horizons, it is obvious' that in a now and practically unprospected ilistri.t the exact depth at which oil may be expected must he ascertained by trial bores. The tendency of oil to occur along anticlinal axes is well known, and therefore it is important to locate any anticlines that may bo present in the Kotuku strata. Further boring is necessary to determine with certainty the presence and exact position of an anticline. This need not be of a costly character. To s'um up, it may he said that the prospects of obtaining oil in quantity at Kotnku are so promising that the expenditure of a considerable amount of capital in further trial borings would be fully justified.