Cotton. — The Uplifted East Coast of Marlborough. 



291 



The higher terrace remnants in the vicinity of Kekerangu do not pre- 

 serve a good record of the earlier movements, but more information is to 

 be obtained from the uplifted Clarence delta, a little farther south. 



2. The Uplifted Clarence Delta. 



The convex curve of the shore-line at the mouth of the Clarence suggests 

 that the river is building a delta, and this is found to be the case, although 

 only a small proportion of the projection is a delta built with respect to 

 present sea-level. The remainder is a promontory of high land, an uplifted 

 delta, through which the river makes its way to debouch at the point (see 

 figs. 5, 6, and 7). 





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v - >/,. •l:~%w — 



Fig. 6. — View of the Uplifted and Modern Deltas, Low Terraces, and Flood- 

 plain of the Clarence River from a Point on the Surface of the Uplifted 

 Delta on the South Side. 



The promonotory so formed is flat-topped, the surface sloping gently 

 seaward, and reaches a height of 580 ft. about half a mile within the 

 present clifTed margin, to which the subaerial top-set beds extend. 



It is impossible to say with certainty how far seaward from the present 

 margin of the platform the strand lay at the close of the period during 



Fig. 7. — View of the Clarence Delta from the North. 



which the delta was built. The amount of uplift indicated may be taken 

 as 500 ft., which is about the height of the base of the top-set beds. 



The least dissected portion of the surface of the ancient delta lies close 

 to the north bank of the Clarence. The even edge of this portion appears 

 in fig. 6. It has escaped dissection because it slopes away from the river. 



The writer crossed the southern portion, and found that its dissection 

 shows at least three distinct stages. A broadly rolling, mature, upland 

 surface points to a very long period of rest following an early movement 

 of uplift of small amount, though, on the other hand, this dissection might 



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