258 



Notes on a High-level Occurrence of a Fossil- 

 iferous bed of upper cainozoic age in the 

 neighbourhood of the murray plains. 



By W ALTER Howchin, F.G.S. 



[Read August 10, 1916.] 



In previous notices U) the broken and fragmentary 

 occurrences of the fossiliferous beds of Cainozoic age in South 

 Australia have been commented upon and the great range 

 of altitude exhibited by these beds has been used as collateral 

 evidence in proof of locally-developed earth movements. Up 

 to the present the evidence has been supplied mostly by the 

 older fossiliferous series, which have been shown to give a 

 vertical range, in successive steps, of about 2,500 feet.( 2 > 



The upper marine series (Tate's "Miocene") does not 

 show the same range in its respective altitudes as the lower 

 series. The city of Adelaide is built on a platform of these 

 beds at a height of 100 feet above sea-level. They occur in 

 many places in the sea cliffs of Gulf St. Vincent, at about the 

 same level, or less, and also in the cliffs of the River Murray 

 at about 40 feet above sea-level. 



The greatest elevation of the Upper Cainozoic marine beds 

 on the western side of the ranges, so far as known, occurs 

 near Hallett's Cove. In the cove itself the fossiliferous ( ! 

 Miocene occupies a position in the face of the cliffs, between 

 the Permo-carboniferous till and the Pleistocene clays, at a 

 height of 100 feet above sea-level ; but at the distance of a 

 mile inland the same beds are repeated, resting on a shelf of 

 Upper Cambrian rocks, at a height of about 200 feet above 

 sea-level. An additional occurrence is described in the 

 present paper at a still greater elevation. 



(l) Howchin : "Description of a Disturbed Area of Cainozoic Rocks 

 in South Australia," Trans, and Proc. Roy. Soc. S. Aus., vol. xxxv. 

 (1911), p. 47; "An Outlier of Older Cainozoic Rocks in the River 

 Light near Mallala," ditto, vol. xxxvi. (1912), p. 14 ; "Foramini- 

 fera and other Organic Remains obtained from Borings on the 

 Lilydale Sheep-station, 7 ' ditto, vol. xxxix. (1915), p. 345. 



(2) Tate fixed the base of the Lower Cainozoic fossiliferous beds, 

 in the Croydon bore, at 1,681 feet ; so that when the height of the 

 bore above sea-level (57 feet) is allowed for, and the height of the 

 fossiliferous fragment on the Hindmarsh Tiers (about 900 feet 

 above sea-level) is added, we got an extreme vortical range of 

 these beds as 2,524 feet. 



