PETROLEUM.

Taranaki Daily News, Volume LI, Issue 260, 27 October 1908, Page 4

PETROLEUM.

THE DEPTH OF OIL. CapL Harry Andrews writes to the Uilhngtoa 'limes:— Nuiuing will ever take the place of experience in donning the depth limit on test wells. J- u Pennsylvania petroleum is found in porous formations generally in anticlines and monoclines. In West Virginia avid Canada it is fwmd under anticlinal crowns, and several locations in New Zealand would come under this head. The Government Geologist in charge of the survey of ihe oil regions o: Pennsylvania says:—- Xotwitiistaiiding the large number of deep wells put down in this country, 1 have never heard of a well producing oil from a depth of 2000 feet below the surface, and the oil rock i s above tide-level. In Warren County the oil-producing sand lies about 1000 feet above oceaa-level, the higitest altitude at which oil has been found in that State, while in Armstrong County the rock has sunk to very near tide-level: and in Butler County to 500 feet lielow tide. All the oil thus far produced in Pennsylvania has come from strata, lung between a point juO leel below ocean-level and 1000 feet above on-ean-kvel, and no oil has yet been produced here from rooKs below oceanlevel, except from those wells located in Armstrong and Butler Counties."

Again, lie states tiiat all deep wells have proved failures that onlv salt water and gas has been obtained where oil was expected. The above is quoted to that in the interior, far from coastal conditions in New Zealand, lest wells would have as good prospects for payable oil as in coastal districts. On the other hand, on (lie coastal fields of California, where the a vera "c depth of the best welU is 1000 feet below surface, from which tens of millions of barrels of oil are taken annually, we have the Los Alamos well, at Santa Maria, 4351) feet in depth, which is producing GUI) barrels of 35 gravity petroleum per day. It must bo renieu'ibei'ed. however, that this is in an exceptionally productive lield, and it is very questionable if this remarkable well should be used as an inventive to .put down all twt wells on a new field to a great depth. From personal experience and the records of deep wells to date, I do not think it should. Vet much will depend upon the formations eneount< red. and oil and gas indications obtained. In this I doubt if the value of experience could be over-rated. ' New Zealand has been going through an apprenticeship in oil product- for 40 years, which usually last but two or three in other new fields, but if woflc is continued here on more scientific lines, and former mistakes avoided, a rich strike of oil will yet be made, repaying ten-fold all previous outlays.