;:5(>2 Tranmctionti. 



Von Hochstetter* divided the cotils of west Nelson into two series — 

 Mesozoic and Tertiary — mainly on account of the difference in composition. 

 Von Haastt does the same. ' CoxJ divided the coals between the Lower 

 Greensand and Cretaceo-tertiary on stratigraphical grounds ; but, evidently 

 influenced by the difference in composition, Hutton§ placed the coals of 

 Nelson and Motupipi in the Oamaru series, and those of Pakawau, Wanga- 

 peka, Westport, Greymouth, and Reefton in the Amuri series, of Cretaceous 

 age. Hector II has pointed out the anomahes connected with this classi- 

 fication, and has shown that, as far as west Nelson is concerned, the 

 palaeontological evidence upon which Hutton rehed for his classification 

 was very incomplete. Park^ at first recognized two coal-horizons, but 

 now, as the result of later investigation, places the Wanganui and Inanga- 

 hua, Westport, and Greymouth coals in the Oamaru series, of Lower Mio- 

 <-ene age. Von Ettingshausen,** from an examination of the fossil plants, 

 considered the strata at Pakawau, Wangapeka. Greymouth, and Reefton of 

 Cretaceous age. Hector ft placed all the coals of west Nelson at the base of 

 his Cretaceo-tertiary, but considered that the coals occur in an upper and a 

 lower horizon. Mackay %% placed the seams in the Cretaceo-tertiary, and did 

 not express any opinion as to their occurrence in different horizons. 



From the above it will be seen that very considerable difference of 

 opinion has existed as to age and relationships of these beds. 



The writer will attempt to show that the coal-seams may occur in one 

 series of beds. Wherever the basement rock of the coal series is exposed 

 the coal-seams rest either hard on the basement rock or on sandstones and 

 conglomerates immediately overlying it. Such is the case in the Pakawau 

 field, at Motupipi, Nelson, the Owen, Reefton, Charleston, Denniston, 

 and other points. In the Greymouth field the semi-anthracites of Paparoa, 

 the sub-bituminous coals of Blackball, and the brown coals of MoonlighF 

 Creek all lie very near the basement slate. 



At Point Elizabeth the rocks are downfaulted, and the coal rests upon 

 a considerable thickness of sandstone and shale. These lower beds may 

 possibly represent the coal-measures of Mount Davy. At West Wanganui 

 the coal overlies sandstone, &c., but the basement rock is nowhere visible. 

 These coals have been downfaulted, as is indicated by the difference in 

 strike of the comparatively elevated outliers near Golden Blocks, and 

 there is nothing to show that the West Wanganui coals overlie these or 

 the Pakawau coals. 



Again, with the seams at Moonhght, Blackball, and Paparoa, which 

 are taken in ascending order of elevation and carbonization, it is difficult, 

 if not impossible, to account for their relative positions except on the 

 assumption that they all belong to the same horizon and owe their present 

 positions to faulting, and their various compositions to different distillation- 

 conditions. Again, in no section do the brown or sub-bituminous coals 

 actually overlie the bituminous senras, nor do the limestones — which at 



* Hochstetter : " New Zealand," pp. 58, 59, 85. 



f Haast: Geology of W. Nelson. 



X Cox : Geol. Surv., No. 15, pp. 71-73 ; No. Hi, i)[). 5-8. 



§ Hutton : Trans. N.Z. Inst., vol. 22, p. 387. 



II Hector : Geol. Surv., No. 21, p. xxxv. 



Tf Park : " Geology of New Zealand," 1910, p. 293. 

 ** Von Ettingshausen : Trans. N.Z. Inst., vol. 23, p. 241. 

 tt Hector: Geol. Surv., No. 18, p. xxxii el seq. ; No. 21, p. xxxv ct seq. 

 jj Mackay : Geology of S.W. Nelson, pp. 57-61 ; Papers and Reports relating <o 

 Minerals and Mining, 1900, C.-6, p. 4. 



