OIL SEARCH IN NEW ZEALAND

Press, Volume LXXXVI, Issue 26123, 27 May 1950, Page 3

OIL SEARCH IN NEW ZEALAND

NEW APPROACH MAY YIELD RESULTS DISTRICT * GEOLOGIST’S VIEWS “The statement made by Mr S. Paul Hart, of Los Angeles, in Auckland recently, and published in ‘The Press’ last Saturday, that ‘he knows that the mineral (oil) is not to be had on a commercial scale in New Zealand.’ appears to be altogether too dogmatic and premature,” said the district geologist of the Geological Survey (Mr B. W. Collins) in a statement.

“All that the geological work and drilling done since the passing of the Petroleum Act in 1937 have proved is that commercial deposits of oil are not present in the areas tested up to the depths reached by the drill." continued Mr Collins. “There are large areas’ of New Zealand, as yet quit? untested, which may yet produce appreciable quantities of oil on a/Commercial basis.

“All the deep xvells drilled in the search for oil betxveen 1939 and 1944, mainly by American companies, were intended to test at depth geological structures found from surface evidence. The structural type of oil trap is the easiest to find, but it is by no means the only type.” added Mr Collins. “At the present time probably about two-thirds of the world’s ou'put of crude oil is being produced from other types of accumulations which are becoming more and more important. It is already accepted in the United States, for instance, that further discoveries of oil in the conventional structural type of trap are not to be expected. Other types of new oil pools are still being found, however. Admittedly the search is becoming more difficult, but the rexvards are just as great as previously. Remarks of Minister “In 1944 the late Mr P. C. Webb, at that time Minister of Mines, said of oil search in Nexv Zealand, ‘The fact must now be faced that oil pools of the structural-trap nature, for the location of which search has so far been directed, appear difficult to find. However, during recent years searca in the older oil-producing countries has been directed toward oil-pools of the stratigraphic-trap nature as an outcome of the completion of investi-! gatiqns of favourable structures. The possibility of the existence of oilpools determined by stratigraphic traps in Nexv Zealand cannot as vet be discounted, and. xvhile the search for such is far from simple. I have no doubt that this approach to oil exploration will in time receive the attention it warrants. Much work still remains to be done in the exploration of the possible oil resources of New Zealand.’

“Later in the same year, when reviewing the work of the Zealand Petroleum Company. Mr Webb stated that the search had not entirely eliminated the possibility of finding oil in Nexx- Zealand, but ; t had unfortunately left less confidence in future exploration.

“These statements are still valid and xvould be upheld by all geologists with any knowledge of petroleum exploration." said Mr Collins. “The late Mr E. O. Macpherson, of the New Zealand Geological Survey, writing in 1946. stated that ‘failure to find oil is the common experience of oil-men. especially when prospecting new country. but failure satisfactorily to test and eliminate a region is entirely disappointing. This seems to be th? situation in New Zealand.’ He then referred to the unsuccessful testing of structural traps in Nexv Zealand, and added that stratigraphic traps ‘have not been seriously searched for, or tested in this country.’ “Mr Macpherson concluded his memoir (published bv the Department of Scientific and Industrial Research) as follows: “The not unattractive features of prospective oil lands in this country—thick sedimentary sections, likely source beds, a few oil seepages and very many gas seepages, and the strong probability of stratigraphic traps of various types on the flank uplifts—will continue to offer chances for the venturesome. Another kind of oil-men will some day enter this field and for them this discussion on growing folds and buried ridges may be of interest.’ Expenditure in N.Z. “From my own experience of petroleum geology, in Nexx’ Guinea in 193738 and Nexx’ Zealand xvith the New Zealand Petroleum Company from 1939 to 1942, I am in fuFl agreement xvith these statements," said Mr Collins. “The possibility of stratigraphic traps containing commercial quantities ; of oil in Nexv Zealand remains. No organised search for this type of petroleum accumulation has yet been made in this country. No doubt the search would be expensive, but techniques are being continuously improved. The chances of finding oil may be slirtl. as claimed by Mr Hart, but whether they are worth taking or not is still a matter of opinion. Only 10 years ago several American and English companies thought it worth while to spend a total of about £2.000.000 in the search for oil in New Zealand. Unfortunately their search proved fruitless, but at least showed where not to look for oil in the future. The possibilities were narrowed doxvn somewhat, but certainly not eliminated entirely.

“In my opinion the possibility of stratigraphic traps eventually being found in the Taranaki-Manawatu area is by no means remote.” continued Mr Collins. “As far as Canterbury is concerned. however, although the opinion has been expressed that oil may occur beneath the Canterbury Plains. I do not think the discovery of oil pools here at all probable. The thickness and nature of possible oil-bearing rocks exposed in the foothills of the province are not such as to warrant holding any hopes of the occurrence of petroliferous rocks under the gravels of the plains.

Chertsey Well Recalled Between 1914 and 1921 a well was arilled at Chertsey, near Ashburton, to a depth of 2170 feet in scorch of oil. but failed Io penetrate through the alluvial deposits of gravels sands, and clays forming the plains. If oil-bear-ing rocks exist they will be below this depth, m the Chertsey area at least. Another point to be remembered is the difficulty of drilling to depths greater than a few’ hundred feet in the gravels of Canterbury. Canterbury, however, has vast quantities of a liquid mineral of importance equal to or greater than petroleum—ground water." said Mr Collins. “The amount of ground xvater under the Canterbury Plains would be sufficient to supply the entire domestic and industrial needs of New Zealand. Ground xvater has many advantages over surface xvater or rain water and Canterbury should be axx’are of its great asset."