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the clay being carried forward in suspension and the sand deposited. This bed 

 is not seen in the glacial beds that face the sea at Hallett's Cove, which are at a 

 higher level than the base of the white sand bed, so that it is possible that the 

 latter occupies an eroded gutter in the boulder beds. 



The assumption that the white sand bed at Hallett's Cove is stratigraphically 

 related to the glacial beds gathers strength from the fact that at Queenscliffe, 

 Kangaroo Island, a white sand bed rests upon the glacial clays, and, at the same 

 place, the fossiliferous Miocene appears to occupy an eroded trench in this bed. 

 Five miles to the west of Queenscliffe a similar white sand bed outcrops at 

 the Gap Hills, where it rests upon the glacial clays and is overlain by a basaltic 

 sheet (Howchin, W., 1899 and 1903). 



Lower Pliocene Beds in Section B. 



Next above the white sand bed, in the order of succession at Hallett's Cove, are 

 the Lower Pliocene fossiliferous and calcareous sandstones. They have their 

 greatest local thickness (12 feet) at their northern extremity (described under 

 Section A) where they rest on glacial clay, which is held up by the Cambrian 

 slates that form the cliffs at Black Point. They gradually decrease in thickness 

 and thin out to nothing at the head of the Cove, where they give place 

 to a thick, feebly-cemented bed of white sand which is destitute of organic 

 remains and occupies an inferior position to the fossiliferous beds, as described 

 above. Within the limits of the Cove the base of the Lower Pliocene is con- 

 glomeratic by the inclusion of water-worn erratics gathered from the underlying 

 till. 



Another outcrop of the fossiliferous Lower Pliocene sandstones occurs on 

 the rising ground, about three-quarters of a mile to the eastward of Hallett's 

 Cove, in Sees. 564, 565, Hundred of Noarlunga. The beds occur on the western 

 side of the north and south district road, in scrub country. The beds form a 

 retreating scarp, about 12 feet in height and half a mile in length, ending at 

 their southern extremity close to the road that has form^ed the main road to the 

 Cove. The rock is a siliceous sandstone, and, in places, a calcareo-siliceous 

 sandstone, often gritty, and includes angular to rounded fragments of quartz, 

 purple slates, etc., sporadically distributed through the sediments. The greater 

 part of the rock seems almost destitute of organic remains, but, in places, a 

 limited variety of fossil impressions on the rock are massed in considerable 

 numbers. The commonest form appears to be Tellina lata, which, although not 

 previously recognized at Hallett's Cove, has been recorded from the Upper 

 Series at Aldinga. An external impression of a suborbicular bivalve with rather 

 strong concentric lines may possibly represent a Lucina. The beds on their 

 northern side are seen to rest on the purple slates and are covered throughout by 

 a considerable mantle of travertine, which is exhumed and used for the building 

 of dry walls, etc., in the neighbourhood as well as burnt for lime. The situation 

 of the beds is fully 100 feet above the outcrop of beds of similar age at the 

 adjacent Cove, and 200 feet above sea level. With the exception of the Mount 

 Mary occurrence (Howchin, W., 1916, p. 258) this is, so far as known, the 

 greatest altitude of the Lower Pliocene sediments in South Australia. 



Resting on the Lower Pliocene fossiliferous beds is a white, somewhat 

 compact, limestone, which is a very general feature of the Lower Pliocene beds 

 throughout the district. It is unfossiliferous— except, at times, near the plane 

 of junction with the underlying fossiliferous bed — and is, probably, of secondary 

 origin, the lime, in the first instance, having been extracted from the underlying 

 bed, by solution, and then redeposited at the surface as a travertine mantle. 

 This supposed ancient travertine is sometimes separated from a more recent 

 deposit of travertine by clays, while, in other places, it passes up into a more 

 J 



