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towards the north-east of the covering strata and of the floor on which 

 they lie, as shown in fig. 4, h, combined with resistance to erosion offered 

 by indurated conglomerate at the base oi the cover. 



Tilted and Stripped Plateau of the South-eastern Side of the Aorere 



Valley. 



Turning now to the south-eastern side of the Aorere Valley, one's 

 attention is arrested by a tilted denudation plain which rises from the 

 valley lowland to a height of about 1,500 ft. in a distance of three miles 

 and a half. Tliis plain from some points of view appears very well 

 preserved, but closer inspection reveals the fact that it is deeply divided 

 by the steep-walled gorges of numerous streams tributary to the Aorere. 

 The form of this south-eastern slope was noted by Hochstetter,* who 

 estimated its inclination as 8°, but did not remark upon its genesis. 

 It was remarked upon later by Park (p. 198), McKay (1896, p. 2-3), and 

 Bell (pp. 24—25), McKay explaining it as a plain of marine denudation 

 and Bell referring to it as an " old sea-shelf." 



Fig. 4. — Alternative interpretations of the Wakamarama fault-scarp section. 



Fig. 5. — -Dissection of a sloping surface, such as that of the south-eastern side of the 



Aorere Valley, by streams from a higher block behind it. The initial form is shown 



in the right-hand block. 



McKay describes it as a " feature characterizing the east side of the 

 Aorere Valley," and adds, " This is an uniform slope of the country 

 to the north-west and the low grounds of the valley, from heights 1,200 ft. 

 to 1,500 ft. above the sea, which slope, as seen from a distance, appears 

 to be remarkably uniform, both as regards its dip towards the low 

 grounds and as regards its extension along this side of the Aorere Valley, 

 and suggests at once the idea of a plane [sic] of marine denudation, 

 which, by the elevation of the mountain i-egion to the south, has acquired 

 a steeper slope than it had when first formed " (1896, p. 2-3). Illustra- 

 tions are given by Hochstetter (woodcut on p. 103) and by Bell (pi. i, 

 lower view, and pi. ii, upper view). 



*F. V. Hochstetter, "New Zealand," Stuttgart, 1867, p. 105. 



