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this gravel-masS the Big Awakino flows, entrenched bel6w the general surface 

 of its former valley-plain, which in this portion of its coiirse, over the area 

 lying between the two faults referred to above, is about a quarter of a mile 

 wide. At the coal-mine the stream enters a narrow gorge, which it has 

 cut through the Awakino tilted block on its way to join the Waitaki River. 

 The Big Awakino pursues a remarkably straight course from its source, 

 near the crest-line of the Kurow Moimtains, to its mouth, and this course 

 is evidently consequent on the initial deformation ; but, as the movements 

 were probably not simultaneous over the whole of northern Otago, the uplift 

 of the Awakino block may have commenced later. The course of the Big 

 Awakino across the Awakino block in a narrow gorge-like channel must 

 be considered as antecedent to the uplift of this block. Its lower course 

 is therefore what Cotton (1917a, p. 253) has termed " anteconsequent." 



(4.) Kurow River to Otiake River. 



On the left bank of the Kurow River, four miles above its junction with 

 the Waitaki River, an outcrop of fossiliferous Tertiary rocks occurs. There 

 is only a small exposure, extending along the bank for about 30 yards. The 

 rocks dip at an angle of 46° towards the south-west, and the Maitai rocks 

 rise steeply a short distance from these beds. The junction is again obscured 

 by the gravel deposits, but it is imdoubtedly a faulted one. The Tertiary 

 exposure here consists of a hardened calcareous greensand containing 

 Foraminifera, mainly in the form of glauconitic casts. Minute subangular 

 grains of quartz also occur. The larger fossils are poorly preserved, and 

 specific identifications could not be' made. The following genera were 

 found : Cucullaea, Malletia, Panope, Pecten. This outcrop is on the line 

 of the Wharekuri-Otekaike fault. 



The outcrops of Tertiary rocks are few and scattered between the Kurow 

 River and the Otiake River. About three-quarters of a mile to the south- 

 east of the last locality quartz-grits occur in places, and farther on there is 

 a small exposure of a glauconitic calcareous rock. The only forms obtained 

 were Dentalium solidum Hutt. and Limopsis aurita (Brocchi) . Near the source 

 of the most southerly tributary of Malcolm's Creek the quartz-grits again 

 crop out, flanked to the south-west by the steeply rising foothills of the 

 ranges. Traces of greyish-green glauconitic sandstones were foimd near 

 Trig. Station N. In a cutting on the road that leads from Malcolm's Creek 

 to the basin of the Otiake River there is a small outcrop of calcareous 

 rock, from which the following fossils were obtained : — 

 Corhula canaliculata Hutt. *Malletia australis (Q. & G.) 



Cytherea chariessa Sut. Nucula saggitata Sut. 



Dentalium solidum Hutt. Panope sp. 



* Limopsis aurita (Brocchi) Pecten huttoni (Park) 



Traces of brachiopods were also found. 



A mile from the railway-line the following section (fig. 3) is exposed on 

 the right bank of the Otiake River : — 



«y (^ (c) Ch) (a,; 



Fig. 3. — Section, right bank of Otiake River, (a), Limestone (Otekaike limestone); 

 (6), glauconitic calcareous shell-bed ; (c), calcareous sandy mudstone ; 

 {d), hardened calcareous glauconitic bed ; (e), calcareous sandy mudstone. 



