98 president's address— section c. 



This conclusion extends Dr. Henderson's (1917) deductions from 

 the features of the Reefton district, and is a most important addi- 

 tion to the discussion of the Tertiary history of New Zealand. 



The Hawkes Bay district has been a type-district for the study 

 of the Upper Tertiary sediments sincei the explorations of McKay 

 (1879-1887), but as no detailed investigation has been published 

 concerning this area during the last decade, no account of it will 

 be given here. Morgan (1914) and Thomson (1914, 1918) have 

 made rapid investigations of the extension of the formations of the 

 Hawkes Bay district southwards between the Ruahine and East 

 Coast Ranges towards the Wairarapa district and Palliser Bay, 

 and further work by Thomson is in progress in the latter region. 

 He is of opinion that it dees not belong to the same diastrophic 

 province as that containing Hawkes Bay, but is rather to be 

 assigned to the same diastrophic province as the Awatere beds of 

 East Marlborough, characterized by a marine transgression com- 

 mencing near the close of the Oamaruian, and extending through 

 the succeeding epoch, and affecting areas not submerged during the 

 lower Noto'cene transgressions. Nevertheless, the region of 

 Oamaruian depo'sition was not far distant from here, and evidence 

 of a mid-Tertiary unconformity appears to be afforded by the oc- 

 currence of derived Oamaruian fossils in an upper Tertiary mud- 

 stone-conglomerate (Thomson, 1919).* 



On the other side of the island we have to record much in- 

 teresting work Park (1887) showed that there existed here a 

 great series of Upper Tertiary beds extending into' the centre of the 

 island. Speight's (1908) observations indicate that they rest upon 

 a planed surface of greywacke, &c., which extends beyond the 

 margin of the marine rocks. Apparently the transgression was 

 towards the south-east. As we have pointed out, the lower 

 Tertiary sediments in North Taranaki are unconformably over- 

 lain by sandstone (including coal-measures). Traced to the south- 

 east these give place toi " Upper Miocene " and " Lower Pliocene "■ 

 calcareous sands, clays, and coralline beds, with pebbly shell beds, 

 and these again are followed further toi the south-east by " Upper 

 Pliocene " sandy shell beds, clays, &c. Marshall and Murdoch 

 (1920) rei-examined the fauna of these two last formations, as 

 exposed in the coastal section extending for 20 miles north-west of 

 Wanganui, and originally described by Park (op. cit. pp. 47-57). 

 There are still lower beds which have not yet been re-examined. 

 The dip is constant throughout, being about 4^ deg. towards the 

 S.S.E. As no dislocations of any note appear in the very con- 

 tin nous sections, they are most probablv absent from the inter- 

 vening dune-covered stretches. The lithology is fairly constant 



♦ Thom'»on a!si re'oM'i th"? prpsence of conebment" houliers of Orf ta'-eous rocks in this 

 that h'VB lippn derivod f'-om adjacent firrmt'ons which, however, may belong to the Pre-Noto- 

 cene Lower Cretaceous (?) " East Coast Series." 



