Cotton. — Notes on Wellington Physiography. 



257 





•2? 



2z 



Lyell,* affected both sides of Cook Strait. It was, however, a tilt to 

 the west, which depressed the western shore of the strait and elevated 



the Wellington side as a whole — that is, the area 

 ^ shown in fig. 1 — by an amount varying from zero 

 ,-op on the north-west to about 9 ft. on the south- 

 a east. The raised beaches of the Wellington coast 

 ■5 which owe their elevation to that movement have 

 o been described and figured by Bell.f They may 

 •a be seen also in Plate XVIII, fig. 2, and" Plate 

 m> XXI, fig. 2. Both views are of parts of the 

 g eastern shore of Miramar Peninsula. 

 J There is some evidence that this tilt is a 



§j continuation of an earlier tilting movement in 

 ^ the same direction, the axis of the movement 

 J lying a little to the west of Wellington. On the 

 •g south-east a series of very fresh raised gravel 

 a beaches at Cape Turakirae, the highest being 

 g 90 ft. above the sea. are mentioned by Aston. J 

 On the north-west there appears to have been 

 a downward movement of small amount subse- 

 quently to the general movement of elevation 

 the proofs of which have been given. This move- 

 ment, which has drowned the lower reach of the 

 Porirua Stream, does not appear to have been 

 more than 30 ft. or 40 ft. The stream had previ- 

 ously developed a broad strip of flood-plain, and 

 this has been drowned to a distance of about a 

 mile and a half from the sea. At Porirua there 

 appears to have been little or no movement either 

 up or down in 1855. Raised rock platforms 

 similar to those at Wellington are not found. 

 This agrees with the accounts of eye-witnesses 

 given in substance by Lyell. § 



3 



^8 



Vy 



\ V- 



W <d 



V s The Wellington Fault. 



» | The Fault-scarp. 



2 -g The following account may serve to supple- 



^ ment the " proof of the great fault along the 

 J western side of Wellington Harbour " given by 

 «« Bell. 1 1 In fig. 1 the line of faulting is indicated 

 _c as " Wellington fault " (see also fig. 9, a sketch 

 g of the fault-scarp as seen from Kelburne, and 

 S Plate XIX, fig. 2, a photograph from Petone). For 

 Js the length of this line, about six miles, the Port 

 Nicholson depression is bounded by an abrupt 

 scarp with a base-line almost perfectly straight, 

 the departure from perfect alignment consisting of two very gentle curves, 

 concave towards the shore, separated by a similar convex curve of very 



* " Principles of Geology," 10th ed., 1868, vol. 2, p. 82. 

 t Trans. N.Z. Inst., vol. 42, 1910, p. 538, and pi. 41 and 42. 

 % B. C. Aston, this volume, p. 208. 

 § Loc. cit. 

 || Loc. cit., p. 539. 

 -Trans. 



