BartrUjVI. — A Fossiliferous Bed at Kama Creek. 101 



Art. XIII.— .4 Fossiliferous Bed at Kawa Creek, West Coast, South of 



Waikato River, New Zealand. 



By J. A. Bartrum, Auckland University College. 



[Read before the Auckland Institute, 20th December, 19hS ; received by Editor 

 30th December, WIS ; issued seimrately, 26th May., lOJfJ.] 



Whilst on a liurried trip from Port Waikato to Raglan early in 1917 the 

 writer observed at the coast near Kawa Creek, about fourteen miles south 

 of the Waikato River, a very interesting section in the Tertiary succession 

 and discovered a fossiliferous bed that had escaped the notice of earlier 

 geologists examining the coast section. He was able later to spend about 

 a day and a half collecting from this bed, in which he found molluscan 

 fossils m great numbers, but very fragile and without great variety. No 

 doubt, however, further collecting will add greatly to the present list of 

 fauna. Even though incomplete, this list shows many points of interest 

 and the object of this note is to illustrate these, and to publish some facts 

 m connection with the more recent geological history of the Kawa Creek 

 district that may have more than local interest, and help to throw light 

 upon the mutual relationships of the later Notocene beds of a wide 

 diastrophic district.* 



Resume of the Geology op Kawa Creek - Port Waikato District. 

 The oldest rocks exposed m the area studied are Mesozoic shales, sand- 

 stones, and local conglomerates, best exposed in the vicinity of Port Wai- 

 kato They are disposed in a somewhat irregular asymmetrical anticline 

 of which the axis is situated about half a mile east of the coast-line, to 

 which its strike approximates. The western limb is the steeper, the dips 

 there varying from 20° to 50°, whilst the strikes, unless where local 

 complications occur, range approximately from north-west to N. 5° E. 

 In the core of the anticline appear dark-grey to black marine shales with 

 locally abundant belemnites, moderately frequent pelecypods and brachio- 

 pods, and occasional gasteropods. Above these are well-bedded alternating 

 sandstones and shales, with minor conglomerate, in which plant-remains 

 are ubiquitous, and which furnish one of the best collecting-grounds for 

 Mesozoic plants in New Zealand. The late Dr. E. A. Newell Arber has 

 recently described the flora as Neocomian in age.f 



Resting discordantly upon the eroded edges of the Neocomian are lime- 

 stones of the Notocene, usually fairly pure, but sometimes very marly 

 Near their base they are strongly algal, and contain abundant fragments 

 of the Mesozoic shales, a fact well shown near the mouth of the Huruwai 

 Stream on the coast section. What fossils have been collected from these 

 limestones have their analogues in the Oamaruian of other parts of New 

 Zealand, t Warping, minor folding, and some faulting have caused the 



* J. A. Thomson, Diastrophic and other Considerations in Classification and 

 Con-elation, and the Existence of Minor Diastrophic Districts in the Notocene, Trans. 

 JS.Z. Inst., vol. 49, pp. 397-417, 1917. 



Ir^nJi^^ ^■.^''v'''^^ t''^''?.' ^^"^ ^^''^"' Mesozoic Floras of New Zealand, Palaeonto- 

 logical Bvlletm Ao. 6, N.Z. Geological Survey, 1917. 



X Dr. -J. A. Thomson very kindly examined the brachiopods for the writer. 



