Cotton. — Geomorphology of South-western Wellington. 



213 



folded, so that the strata are now everywhere nearly vertical, and the strike, 

 though variable from point to point, averages a little to the east of north. 

 Some bands of the rock are thoroughly shattered and allow of the perco- 

 lation of water along closely spaced joints, so that they yield rather readily 

 to deep weathering and erosion. Other bands have escaped shattering 

 or have had the network of crevices re-sealed by a deposit of secondary 

 mineral matter, so that there are now few joints, and weathering and 

 erosion go on relatively slowly. These latter relatively resistant bands of 



Wtxiruxi, R. 



-175 



Fig. 1. — Map of the coastal district of south-western Wellington, including the 

 upland ranges eastward to the main divide. Scale, 10 miles to 1 in. The 

 inset map shows the locality. 



rock stand out boldly as ridges, while the bands of shattered rock are now 

 followed by streams, and, where of considerable breadth, are reduced to 

 somewhat subdued forms with moderate relief. 



It is not known with certainty that the alternating bands of resistant 

 and weak rocks, which owe their varying strength, as just noted, to the 

 extent to which they are fissured, correspond exactly to the bedding ; but 

 they are at least elongated in the same general north-north-easterly direc- 

 tion, and the shattering in the weakened bands was probably caused by 



