MOKAU COALFIELD.

Taranaki Daily News, 28 June 1919, Page 9

MOKAU COALFIELD.

GREAT. WEALTH'YET-UNTAPPED., I Lately Mr David Whyte supplied: the Wellington Times with some particulars of the above field. The authority for these statements was taken from- Mr •Sydney Fry's (Assoc. M. Aus. I. M.E. and Director of the School of Mines, Beef ton) report, which was placed before the Industries Commission recently. I cannot quite see how this gentleman got liis figures. Well known geologists have surveyed this field, and their estimates fall far short of Mr Fry's.

Park and others estimate the supply at ] 10.000,000 tons as against Mr Fry's The known quantity can only ho estimated by the drill, as has been done in any known field for which correct estimates have been given. I will further on refer to an area which I expect Mr Fry based his estimates on, but it remains to be proved if the field is continuous. The quality of the coal is undoubted. Some day I hope to see our large cargo carriers taking in their fuel from the Port of New Plymouth. Mr Whyte makes this statement: "I believe Mokau is the coming 'Newcastle oi New Zealand.'" ■ The Hon. Mr Myers, Minister in charge of the Coal ...epartment, says that the requirements per annum are: — Railway 300,000 tons, bunkering 440,000, freezing 130,000, gas 240,000, electric light. 70,000, domestic and other requirements available 898,020; total, 2.078,620." Our domestic requirements arc well short of 100,000 tons per annum, and as industries spring up and population increases the demand will equal fully ■5,000,000 tons per annum. We cannot look to the South Tsdand to supply much of this quantity, and it is then that the Mokau and Waikato coal fields will be called on '.o supply the steam and household coal for the bulk of the New Zealand demand. The coal from these districts is equal, if not of a better quality than the coal of Germany, which gives to the industries there the required power to carry nn. This information I have on the best authority. The Mokau field should belong to the State, and a start to develop the same should be mad® at once, so that when the demand sets. in supplies will he available.

In the year ISSO Dr. Hoelistotter passed through the Upper Mokau district and classified the underlying scam at Wairire Falls (Mokauiti) in his Lower Tertiary or Brown Coal Series. Sir James Hector, Director of Geological Surveys for New Zealand says that ho believes the coal formation extends tfroin. Kawhia Harbor to the upper part of the Wattgamii Eiver.

In H. M. Skeet's report to the Surveyor General of his observations whilst doing survey work he states: "The coai field of the Mokau-Wanganui district is very extensive and judging by the outcrops o" the lower Tangaraku, middlo Tangaraku, Hcao, Ohura (nedfr Opatu Block), Mokauiti, Mokau, also Tongaporutu near the coast, in all some tnirty two miles long by 20 miles wide.

The Mokau coal is under a heavier cover of sandstone (than the W3ipa and Waikato coals- It is a superior brown coal, commonly classed as a pitch coal. I think it quite possible than underlying the brown coal at Mokau will be found bituminous coal, such as is found' on the wsst coast of Nelson. Park in his book on the geology of New Zealand, page 43, says: "The coal from Stockman's mine iB said to be equal to the Grey coal for steaming purposes." The formation that is present in the Mokau and Awakino districts is of a like character to that of the Nelson province. The same mineral belt that exists there is to be found at the Wairire Falls some 20 miles from the Mokau coal mine. \i'o prove if the same coal bearing scries exist here it is necessary for the Government Mines Department to test-the area.

One or two Diamond drilling plants Aould at once be placed on the field for prospecting, starting from the present mines and drilling towards the Stockman mine west, then due east towards the Wairire Falls, then north through Awakino, at which place good samples of coal have been found, and then worfc south towards the head of the Wanganui River, where it has been found. (See Park's book, page 48). "In 1562 Mr Crawford procured samples, of coal from the Tangaraku Gorge, wMch was procured from a seam with a thickness of S feet and at the Ohura a short distance above its junction with the Wanganui Eiver a 3 feet scam is out-cropping." Park reports (page 104) that at the head of the Heao River fire seams of from 4 to 5 feet thick with ft slight dip south Much money has been spent in and around the West Coast of the South Island by way of prospecting by drill and otherwise and geological survey, and the official reports are anything but encouraging. The* supplies are quickly running out. It is quite evident that the Mokau coalfield should have the immediate attention of the Government. The brown coal measures are found near the surface, and if bituminous coat is found, the eeams should be very much nearer thesurface than the coal measures on the West Coast. This would mean cheapear coal.

Before any big development can. take place, a known area must be ascertained. This can be proved by the di 'mond drill, Not only will these bore' holes and tell us the known quantity of coal in any given area, but they will prove the continuity or the existence of other fields. Quite < recently the?' Government Mine* Department made « small survey of the Retaruke caol-field,-which field "is only a few miles from Brua and Waimarino' stations. This coal is classed as: subbituminous, and is thought to belong to the same series as Mokau. Starting from Molcau coal mine (Stubbs') coal is' found all around, on the Awa-kino-Te Knit! Road, Piopio, Pamako, Mokauiti, Stockman's mine (22% miles below 1 Stubbs' mine), also to the northward of the Mangapapa block. These 1 fields alone would be quite enough for the Mines Department to start work on.I should also like to sec work done at ence on the Tangaraku field, which perhaps, if good coal in quantity is found to exist, would be sooner available for us of Taranaki and Wanganui owing to the Stratford railway passing close to the coal seams. At a later date, if vvc can get a railway to Mokau (where, [ think, some of the best coal in New Zealand will be found) the opening up and development of these mines will mean much wealth to this district. The! railway would also open up for farming purposes much land that' is now being used to produce wool and' beef stock. Settlement would extend. At Mokau large limestone deposits, which could be delivered to the people of New Zealand at a cheap rate, -would help to feed the railway when laid down.' Estimated coal as dux** vejedr-by Hutton,. and Me*

ikay in. tlto districts referred to in this j lletter as, compiled; by 4 Park arei as fol-j low:— ■ J PITCH COffii.. ' Te Kuiti ._.- fr,500,000 Mokau- Awakiho „~ 110,000,000 Upper WangauuL ............ 50,000,000 Total „..._ *«-■. 1155j500,000 BROWN' COAL. Lower Waikato „..,......; 140,000,000 ■■ Drury -..> 8,000,000 Waipa 10,000,u00 Kawhia ~,.... -....; 4,00G,t)00 Total 102,000,000 Only some few thousand tons have been mined of the pitch coal first referred to- This great wealth should not be allowed to be buried.

NESTING A FIELD. If visible out-crops or an open field is seen then the over and undor-lie is known. To prove the field the same order must be found. This is a, test of every field, even when separated by denudation in several basins. It is also a mode of identifying individual coal seams, for, if the strata be continuous, then the seam will have the same accompanying strata above and below. Every field must be tested this way before it can be identified or associated with any known seam. The rule for the identification of coal seams of known value is often of practical importance. It is generally found that a thinning out of both the seams and the accompanying shale and sandstone are indications of the extremes of the field.. As a rule there is a most extraordinary continuity in the strata of the coal measures. All coal bearing strata, like all other strata were, of course, originally horizontal and continuous, but earth movements, such as at taeymouth and Westport, have in most cases folded them in a most strange manner. The Mokau coal measures only dip at slight angles, and have been but little disturbed.

A workable seam must he at least 3 feet thick. A pure sample seam is seldom more than Bto 10 feet thick. We have found ttjob the coal seams are repeated many times in Wales. There are more than. 100 scams, all of which are worked. RELATIVE PRODUCTION OF COAL.

If the extent Of coal area represents approximately the amount of wealth of this kind present in the strata, the production of coal represents how raueji of this wealth is actual capital, it represents the development of those industries dependent on coal, In this respect Great Britain is far advanced of all other countries. It is fully recognised by British statesmen, and scientists are casting about with much anxiety for means by which to promote the more economic use of coal. Fortunately we in the North Island have a very large supply vet untouched. Whether our Mokaii-Wanganui coal is of a •quality for industrial purposes only time' will prove, hut, as I have previously stated, I think good bituminous coal underlies the Mokau brown (pitch) coal .series. Some coals contain 5 per cent of ash, and these are classed as pure coal. Then we have a coal producing more than 10 per cent of ash. This is probably impure and mixed with mud at the time of its accumulation.

The varieties of coal depend on the degree of bituminisation. The previous mentioned varieties consist of pure and impure coals. These consist of perfect and imperfect coals.

Coal, even when pure and perfectly hitumenisod, consists still of many varieties, Laving different uses, depending upon the proportion of fixed volatile matter. These are the true varities of coal. When the combustible matter of a coal contains 90 to 95 per cent fixed carbon it is called anthracite. This is a hard brilliant variety, with conchoidal fracture. It burns with almost, no flame and produces much heat. It is an admirable coal for all household purposes, and, with hot blast, may be used in iron smelting furnaces. If the combustible matter contains 35 per cent fixed carbon and 15 per cent volatile matter, it becomes semi-anthracite or semi-bitumen-ous coal of various grades. These are free burning, rapid burning coals producing long flames' and high temperature, because they do not cake and clog, comomnly known as steam coal. If the combustion matter rises to the proportion of 30 to 50 per cent, it becomes full bitumenous coal, which always burns with a strong bright flame, and often cakes and forms clinkers. This ia perhaps the commonest form of coal, and may be regarded as typical coal.

If the volume approaches or exceeds 50 per cent, then it forms highly biI tumenous or flat or fusing coal, adapted to the manufacture of gaa coke. Since the above was written i have had pointed r out to me the New Zealand Times' report of the Director of Geological Surveys for New Zealand (Mr P. J. Morgan). In giving evidence before the Industries Commission in Wellington on the 21st May of Ihis year, iii> states i "The present coal production is about 250,000 tons. If all the probable coal actually existed and could be minea half the coal supply would last a little over 11 years. The coal snpplv waß inadequate for future generations. A vigorous prospecting policy was necessary if we were to build up industry in I this country. A detailed geological purvey followed by extensive boring | must be done by the Government, the cost' couTd be suitably met by a levy on the coal produced. The cost of prosIpectin'g ought to be refunded by the owners of the coal, a: very substantial and practical reason for the State nationalisation of coal mines: Legislation was necessary to prevent owners of coaFbeaHng- lands from- extracting exorbitant'' royalties." Mr Morgan' supports the purchase of State collieries.