president's address — SECTION c. 95 



strongly suggests that this hne of elevation is also a structural Une. 

 New Zealand, from the importance that has been attached to it 

 by Suess and Dana, deserves special consideration in this matter. 



It is well known that in the south the prominent line of folding 

 from Oamaru to Nugget Point is directed almost at right angles 

 to the coast line, that is nearly E.S.E. It is believed that this hne 

 of fold bends gradually round to the direction of the backbone, • 

 N.N.E., which is its direction at Mt. Cook. Complete observations' 

 are wanting to establish this supposed gradual bend on a basis of 

 fact, though there is no reason to doubt it. Eastwards of Dunedin 

 there is no known continuation of this line of folding which ends 

 abruptly on the sea coast, showing in its transverse section a con- 

 formable series of sandstones and schists all much folded, and the 

 latter in some places contorted, the whole folded area being 150 

 miles across. It is, however, significant that the Bounty Islands, 

 400 miles to the south-east, are formed of granite. 



Similarly, near the East Cape, the direction of strike of the 

 Triassic {?) sandstones that form the western side of the range 

 would carry them out to sea, but there is no indication of the con- 

 tinuation of this line of folds, for the floor of the ocean drops quite 

 abruptly and is soon over 700 fathoms beneath the sea level. 



The rocks that are probably of equivalent age in the Coromandel 

 Peninsula appear to strike nearly due north. Still further north the 

 strike of the rocks" shows little connection with the general trend 

 of the North Auckland Peninsula." 



In these two regions of S.E. and N.W. folding in the south and 

 of elongation in the same direction in the extreme north, Gregory 

 has sought to discover a series of folds older than the main series 

 of the Southern Alps.i Xhis opinion is evidently based on impres- 

 sions only, for in the south, Jurassic and Triassic rocks are highly 

 involved in these folds which are the older series of Gregory. This 

 is also the case in the north, and here it is certainly not yet shown 

 -that the rock folds are directed N.W. and S.E. 2 It therefore 

 appears that the coast of New Zealand does not conform to Suess's 

 statements as to the structure of the coasthnes of the Pacific Ocean, 

 which reads as follows : " With the exception of a part of the coast 

 of Central America in Guatemala, where the bending cordillera of 

 the Antilles has sunk in the whole border of the Pacific Ocean 

 wherever it is known in any detail is formed of mountain chains 

 iolded towards the ocean in such a manner that their outer folds 

 either form the boundary of the mainland itself or lie in front of it 

 as peninsulas and island chains." 



The continuation of the north-east structural line which is here 

 suggested as the true boundary of the Pacific basin is found in the 

 Kermadecs and the Tonga group. The former consist entirely of 

 volcanic material, though blocks of granite derived apparently 

 from a breccia are found in some number in Sunday Island. The 

 Tonga Islands are formed of volcanic material in the western 



1 Gregory, J. W. : Loc. Cit., p. 190. 



2 Clarke. E. dc C, N.Z. Geo. Surv., Bull. 8. p. 42 



