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being developed from stream to stream, and portions of the ridges or spurs 

 were isolated as a kind of monadnocks. 



The Kekerangu Area. 



In the lower valleys of the Kekerangu and neighbouring streams flowing 

 to the east coast across a strip of weak mudstone there is also evidence 



Fig. 4. — The Uplifted Flood-plain and Revived Valley at the Mouth of the 



Kekerangu River. 



of revivals of erosion, and in the period of standstill before the latest of 

 these the Kekerangu had excavated a broad lowland. This was quite pro- 

 bably the same standstill in 

 which the broad uplifted 

 flood-plain of the Awatere 

 was developed. The uplifted 

 Kekerangu flood-plain (see 

 fig. 4) slopes gently seaward, 

 ending in a line of wave-cut 

 cliffs nearly 150 ft. in height, 

 and must have reached a 

 somewhat lower level at the 

 former shore-line. There are, 

 however, reasons for believing 

 that the coast has not been 

 retrograded far, and probably 

 the amount of the uplift is not 

 very far short of 150 ft. ; it 

 may be stated at about 120 ft. 

 The pause preceding the 

 120 ft. uplift was sufficiently 

 long to allow one of the 

 neighbouring streams (Dead- 

 man's Creek) to erode a 

 mature valley through a 

 ridge of resistant conglo- 

 merate (Great Marlborough 



Fig. 5.— Map of the Clarence Delta. conglomerate), which it 



crosses near its mouth, 

 whereas the period that has since elapsed is so short that the gorge cut by 

 the revived stream is still very young, and its grade is interrupted by a fall. 



