OIL IN THERMAL ZONE.

Otago Daily Times, Issue 19039, 8 December 1923, Page 18

OIL IN THERMAL ZONE.

PETROLEUM NEAR TAUPO. OTAGO PROFESSOR’S REPORT. 1 9 PROBLEM OF ECONOMIC IMPORT, t I 3 Petroleum oil seepages at Waiolapu, m the Rotonia-Taupo volcanic zone, provide the subject of an interesting report by Professor Janies Park, of Otago University, in the latest number of the New Zealand '• Journal of Science and Technology. These 8 oil springs, from which the emanations of B gas and oil are plentiful, were examined ’ by Professor Park in 1921, and also by 0 Mr Percy G. Morgan, M.A., whose investi--1 gations were discussed in the sixteenth ■ annual report, New Zealand Geologicaj, 1 Survey, in 1922. f The most prolific seepages, declares Proi fessor Park, occur at the ford on the * cross road between Taupe and Galatea 3 Main roads. On the flat sinter-crusted plat--3 form on the east bank of (he Waiotapu J Stream, a few yards down stream from the I Ford, there are many circular holes filled ■* with hot water, through which there rises 8 an intermittent stream of bubbles of nonJ inflammable gas, aooompanied by bleb? of oil. Around the rim of these gas and oil springs there is an incrustation of dark brown or chocolate coloured ozo-kerilo (a waxlike mineral resin sometimes called native paraffin or mineral wax) ranging t from a mere film to 2in thick. In the bed L of the stream, at the ford itself, there occur r many emanations of gas and oil The oil i breaks at the surface cf the water as amberg coloured rings, and then floats down stream as iridescent films. The gas and oil cmana- • tions near the ford occur over an area of 0 some 25 yards long and 10 yards wide. s By the simple expedient of pushing a rod a few feet into the silt and mud on the ’ stream-bed a strong evolution of gas and ’ oii may be obtained. Half a mile: up-' 0 stream from the ford emissions of nona inflammable gas and oil are ; plentiful, ’ especially on the west hank. The sources of the gas and oil, have not 3 yet been fixed and represent a matter of conjecture. The Waiotnpu area lies in ‘ the Rotorua-Tauoo volcanic zone, and, since" the surface rock is a rhyolitic tuff, the origin of the gas and oil. Professor Park '■ observes, presents a problem of unusual . economic importance. The middle tertiary f rock? occur in the Waikato-Wnipa country 1 to the west of Wniotapu, where they are 7 seen to disappear below the rhyolitic tuff; 0 They consist of n tremendous pile of copt glomerate?, sandstones,' limestones, and: 1 argillaceous strata, and occupy an area many r thousand square miles in extent. To the s ea?t of Galatea the terliaries rise from below the rhyolitic tuff. Thus all the evi--1 donee tends to support Professor Park’s s view’ that thev underlie Ihe whole of the 3 central volcanic regions of the North Island. As a result of examination Professor Park t concludes that the brown coal of the underf lying terliaries are the most probable source 1 of the gas and oil. 5 The professor adds that the association / of volcanic extrusions and oil is well know‘n in some important oilfields. ’ Profitable s oilfields occur along fault-planes in Burma f and elsewhere. ‘Tf the terliaries underlie , the rhyolitic tuffs," concludes Professor a! Park, “as seems most probable the prospect f of finding profitable pools of oil is, in rhy opinion, sufficiently promising to warrant boring at judiciously selected sites.’’