HuTTON. — Geology of North-eastern Otago. 415 



Art. LIV. — On the Geology of the Country between Oamaru 



and Moeraki. 



By Professor F. W. Hutton, F.G-.S. 

 [Read before the Philosophical Institute of Canterbury, 16th July, 1886.] 



Plate XXVI. 



Inteoduction. 



The Hon. W. Mantell was the first geological observer in this 

 district. In 1850 he described the Ototara limestone of Oamaru, 

 the Onekakara clay of Hampden, and the volcanic ash of Kaka- 

 uui. The fossils collected by him were examined by Dr. Mantell, 

 Professor Morris, and Professor Piupert Jones. The Ototara 

 limestone was referred, with doubt, to either the cretaceous or 

 the eocene period ; while the Onekakara clay was considered to 

 be either pleistocene or newer tertiary ; but, at this time, it 

 must be remembered, the recent fauna of the New Zealand 

 coasts was very imperfectly known. Mr. Mantell remarks that 

 he had no opportunity of ascertaining the relative positions of 

 the Ototara limestone and the volcanic ash of Kakanui.* 



In 1865, Dr. Hector placed the Moeraki series (including 

 the Onekakara clay) below the Oamaru series, and considered 

 both to be miocene ; the volcanic rocks he considered to be 

 pliocene.! 



In 1869, Mr. C. Traill, after examining the fossils from 

 Hampden and Awamoa, came to the conclusion that both were 

 probably miocene.;] 



In 1870, Dr. Hector placed the Hampden and Awamoa beds 

 in his Upper, or Struthiolaria series, and the Oamaru limestone 

 (including the Hutchinson's Quarry beds) in his Older, or Ototara 

 series. § 



In my " Catalogue of the Tertiary Mollusca and Echinoder- 

 mata of New Zealand" (1873), as also in my " Report on the 

 Geology of Otago" (1875), I followed Dr. Hector, but called his 

 upper and his older series the Pareora and Oamaru formations 

 respectively. In this latter report I also pointed out that the 

 volcanic rocks of Moeraki overlie the Onekakara clay, thus be- 

 longing to a later period of volcanic activity than those 

 supposed to be associated with the Hutchinson's Quarry beds 

 at Oamaru. 



In December, 1876, and January, 1877, Mr. A. McKay 

 examined the district, and made several important alterations. || 



* "Quar. Jour. Geol. Soc. of London," vol. vi., p. 324. 



t " Quar. Jour. Geol. Soc. of London," vol. xxi., p. 128, and section. 



+ " Trans. N.Z. Inst.," vol. ii., p. 167. 



§ " Cat. Col. Mus.," 1870, pp. 178, 179, and 189. 



II " Rep. of Geol. ExpL," 1876-77, p. 41, etc. 



