336 Transactions. 



than that in the Clan-nce area, since the limestone there is four times as 

 thick. On the other hand, it is only to be expected that the deposition 

 of pelagic beds was continuous on the outer slopes of the continental 

 shelf which must have been formed immediately after the ])ost-Hokonui 

 deformations, and the differential movement of the Kaikoura deformations 

 were certainly large enough to elevate even bottom-set beds above sea- 

 level and certainly extended over a great part of the area covered by the 

 Notocene continental shelf. There is thus no a priori reason whv conform- 

 able pelagic and foreset beds extending from Clarentian to Oamaruian 

 should not be found. The perfect conformity of the limestone to the 

 Clarentian in the area where it is thickest — viz., from the Dee Gorge to 

 Benmore — and the presence of apparent passage beds in the Isolated Hill 

 Creek is most easily explicable on the theory of actual conformity. 



The unconformity in the Herring River does not militate against the 

 above conclusion. The limestone is here very thin, and consists of alter- 

 nations of chalky and marly limestone which must be correlated with the 

 similar band in the Bluff River and the upper of the two similar bands in 

 the Mead Gorge. Two hypotheses in explanation are possible. The Claren- 

 tian beds may have been emergent during the period when the lower part of 

 the limestone in the Mead Gorge was formed, or the upper part of the beds 

 in the Herring River described as Clarentian may be foreset beds younger 

 than the youngest Clarentian beds of the Coverham section. They con- 

 sist of sulphur sands and mudstones similar to those of the Piripauan, and 

 are followed by greensands as in the Piripauan. This resemblance may 

 be more than accidental. The only Albian fossils found at this end of the 

 valley come from beds near the base of the series. 



The absence of flint-beds in the Herring River, however, and their 

 presence in small amount under a small thickness of limestone in the 

 Bluff River, makes it unsafe to predict that the beds immediately beneath 

 the flint-beds of the Hapuku Mountains are Turonian. They may be also 

 Clarentian and separated from the overlying limestone by an unconformity. 

 In the Kekerangu area the limestone appears to be thin and separated by 

 fairly thick mudstone bands, and again in the hills to the north of the 

 lower Ure the limestone is quite thin. Obviously there is still a great 

 deal to be learned about its thickness, nature, and relationshi])s in East 

 Marlborough, and any final conclusions about its age are premature. 



The " Grey MarUr 



The term " grey marls " was first applied by McKay to beds of more 

 or less calcareous mudstone following the Weka Pass stone in the Weka 

 Pass. Similar beds at Amuri Bluff had previously been termed the 

 Turritella beds by von Haast, and the Leda marls by Cox, who correlated 

 them with the so-called Leda marls of Whangape Lake, Waikato. The 

 term " grey marls " was accepted by Hector and applied to beds of similar 

 position and age throughout North Canterbury and Marlborough, and 

 also, owing to a false correlation by McKay, to mudstones underlying 

 the Ototaran limestones of Oamaru and South Canterbury. The " grey 

 marls " were considered by Hector and McKay the closing member of 

 the Cretaceo-Tertiary formation, the succeeding Mount Brown beds in the 

 Weka Pass district being termed " Upper Eocene." So far as Marlborough 

 is concerned, the Cretaceo-Tertiary formation of Hector and McKay had 

 this justification : that the conformable Notocene sequence so far as 

 known closed with the " grey marls," the great Marlborough conglomerate 



