THE KAKAHU MINERALS.

Temuka Leader, Issue 1373, 1 August 1885, Page 2

THE KAKAHU MINERALS.

The following portion of Dr Hector’s report on the Kakahu district was crowded out of our last issue : Memorandum on the Geology and Mineral Resources of the Kakahu District. 15th July, 1885. Hon. Mr Rolleston, M.H.R. With reference to your request for information respecting the mineral resources of the Kakukn district, I have to state that I am not personally acquainted with that district, but having examined the records in the Department and consulted Mr McKay, who is familiar with it and who made a partial report in 1876, (Government Reports 1876-7 p. 46), I am able to furnish you with the enclosed sketch map and notes on the Geological structure of that part of Canterbury. Westwards of the southern parts of the Canterbury Plains, between the Bangitata and the Kakahu Rivers, the mou ciin range embracing Mount Peel, Mount Four Peaks etc., is composed of two distinct formations: an older one, of Upper Devonion age, and the representative of the Te Anau series in this part of the South Island. Rocks of this formation are seen on both sides of, and for a short distance M.E. of, the Kakahu Gorge. ■ Overlying it, and younger than this formation, the rocks of the Mount Four Peaks range and the mountains to the southern bank of the Rangitata belong in part to the Maitai or carboniferous formation, although it is probable that rocks of yet younger date are also largely represented, such as the Permian rocks of Mount Potts series and the Liassic rocks of the Glent Hills, which latter contain fossil plants and thin irregular seams of coal. Flanking these older rocks along the eastern slopes of the mountains referred to, Cretacious and Tertiary strata form a series of downs and low hills stretching from the Orari Gorge to the southern side of the lower end of the Kakahu Gorge, beyond which, more to the S.W.. the same rocks wrap round the older rocks of the Kakahu Gorge, and reaching up the valley of the Opuha River for some distance, stretch also to the S. W. and S. until outside the limits of the Kakahu District. These younger .formations, as stated, are of Tertiary and Ore taceous age. The Tertiary rocks lie nearest to and limit the western extension of the alluvial deposits forming this southern part of the Canterbury Plains. They are mainly formed of greyish-green or brown sands, with marine shells, followed by heavy beds of well rolled gravel, forming the lower hills and downs in the vicinity of Geraldine and on the S.W. bank of the Kakahu River, E. of the outcrop of the Cretaceo-Tertiary rock. Under these there are calcareous sandstones, about which there is some doubt as to whether they belong to the Middle Tertiary peiiod or to the Lowest Tertiary series, which is in the official classification bracketed with the Cretaceous formation as CretaceoTertiary, The Cretaceo-Tertiary rocks consist of calcareous sandstones, chalk marls, greensands, sandy beds, fire clays, and coal, underlaid by quartzoso grit as the lowest rock of the series. Between the Limestone Gorge of the Kakahu River, below the Marble Quarry, and slopes of the range west of the township of Geraldine, the lower or coal-bearing rocks are exposed along a valley having the old rocks of the ToAnau series to th© W. and the limestone scarp, formed by the higher rocks of the coal-bearing series, to the E. Towards the upper end of this valley (ho limestones trend more to the N.E., and an increased breadth of the coal-bearing rocks forms hills of |

rounded outline for the remainder of the distance to the southern bank of the small river passing Geraldine. The formation, stretches further to the northward until it terminates on the southern bank of the Onui River, although it does not pro* bably occupy such a width nor so westerly/ a locality as shown on the sketch, map the northern part of which is taken from Dr Yon Haasl’a The following is an extract from & report made by Mr J. B. btansell, in 1881 ■ Christchurch, January 31, 1881. R. A, Barker, Esq. Dear Sir,—l devoted the greater part of the 28th and the whole of the 29th December, 1880, to an examination of Sections Nos. 21487 and 13611, and the intervening section in the Kakabu district, going over the whole of the ground, and also made an examination in the vicinity. I brought away specimens of a statuary marble immediately below the pug mill ; upon analysis it proves to be equal to any limestone iu New Zealand for the purpose of lime. The pottery clay is a very fair specimen of that material, and in conjunction with the limestone would be suitable for the manufacture of cement. It would be necessary to make it by the dry process, I found a specimen ot clay iron stone in the river-bed below the kilns. Ferguson, the man who is working on the opposite side of the river, says he knows where to find the reef; also glass-making sand and alum shale. If the lust is found in . ooy quantity it should be utilised, as the trouble or expense o£ extracting the alum is very trifling. At the entrance of one of the coal drives on the opposite side of the river 1 fouud an hydraulic lime of passable quality. On the banks of the river to the right as you approach the . Mackenzie Road there exists a reef of , i very good slate about three chains in , width. Upon analysia it bears all the i characteristics of a true slate. The man i living on the section says there is fire i clay to be found. I thirfk he mistakes , the pottery clay for fire clay. I wa»k • unable to find any. If you wish I wfflP ■ send specimens of what I found in the 1 valley,—l am, etc,, 1 J. B. Stahsbll.