218 



Transactions. 



The Paekakariki Coast. 



South -westward from the tapering end of the lowland at Paekakariki 

 the cliffed margin of the old land is now being cut back, and there is no 

 evidence to show whether this part of the coast has ever been prograded. 

 The dune-covered strand-plain is now extending in that direction along the 

 base of a line of high, fresh cliffs cut diagonally across one of the resistant 

 ridges of the old rocks (Plate XIV). 



A mile or two north-eastward, however, there is evidence of the former 

 presence of a strand-plain and of its removal prior to the growth of the 

 present lowland. This evidence is found in the presence of cliffed remnants 

 of fans of locally-derived gravel, one of which is of such dimensions that the 

 fan when complete must have extended seaward about a mile beyond the 

 margin of the old land. 



These fans were built forward in what may be termed the first (strictly 

 the nth) progradational phase (fig. 3, B), following the first (strictly wth) 

 retrogradational phase, in which the cliffs of the ancient coast-line of the 



Fig. 3. — Diagram of successive stages of a coast alternately retrograded and prograded. 



old land were cut (fig. 3, A). These cliffs are now subdued and rounded, 

 and pass by smooth concave curves at the base into the fans and talus 

 slopes. 



The fans are irregularly truncated by a younger line of cliffs developed 

 in a second [(w-(-l)th] retrogradational phase, and these are cut back far 

 enough in places to intersect the line of older cliffs (fig. 3, C). The cliffs 

 previously referred to as lying behind the extreme end of the lowland are 

 continuous with these of the second [(w-f-l)th] retrogradational phase. 



In front of this newer line of cliffs lies the modern lowland or dune- 

 covered strand-plain, a belt of dunes enclosing between themselves and the 

 cliffs a narrow strip of marshy plain (fig. 3, D). Fig. 4 is a panoramic 

 .sketch of this portion of the coast, illustrating the features described. 

 Plate XV, fig. 1, is a photographic view showing the truncated fans. 



