PROSPECTS IN CANTERBURY

Press, Volume XC, Issue 27302, 19 March 1954, Page 12

PROSPECTS IN CANTERBURY

«ESSENTIAL PREMISES EXIST ”

The essential premises for the existence of oil deposits may be present in the Canterbury Plains, according to Dr. E. Lehner ana Mr R. J. L. Stephens, in their report on the prospects of oil in New Zealand. The “essential premises for the existence of .petroliferous conditions” are described by Dr. Lehner and Mr Stephens after some “speculative considerations” of the geological history of the Canterbury Plains. “The picture resulting from these considerations shows the plains as probably underlain by a marine upper creta-ceous-tertiary sequence of 5000 feet or more which may have been gently folded and faulted,” they said. “The existence of buried hills of basement rocks is probable. “Against the probability of major oil accumulations in the plains speak the following facts: “(1) The absence of major oil indications at the edges of the plains. The blobs of inspissated oil reported from the Chertsey well (the only deep well in the plains) can, even if genuine, not be counted for much, especially as they were not followed by further signs in the underlying beds. / “(2) The persistence of volcanic activity throughout the basin until quaternary time. “In spite of these drawbacks, we would consider it a justifiable risk to drill any enclosed anticline of reasonable size which might be discovered somewhere near the centre of the basin,” the report says. 'The search for such a suitable structure can only be made by geophysical means, tout, without ascertaining by actual experiments how the blanketing effect of the thick gravel cover can be overcome, no recommendations can be made regarding the methods.”