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are capped by thick beds of conglomerate that are strongly cemented by calcareous 

 and ferrugineous material. On the paddock in front of the hotel are a great 

 number of well-rounded and perfectly smooth highly-siliceous pebbles scattered 

 over the surface in a light sandy soil. These have probably had a diiTerent 

 origin from the thick gravels on the coast. The very fine grain of these rounded 

 stones produces a conchoidal fracture and was no doubt the principal locality 

 visited by the aborigines of the neighbourhood for obtaining material suitable 

 for making their stone implements. 



A very tenacious and compact white clay, thickly studded with angular frag- 

 ments of white quartzites and some slates, is seen in the deep washouts on the 

 cultivated lands, and especially in the Sellick's Hill Creek, near the township, 

 a little below the main road. It is covered with newer alluvium that is not 

 consolidated, and is of quite different appearance and colour from the former, 

 being a dark-reddish sandy clay and stony alluvium. The division between the 

 two is very sharp. A similar clay and contents appear on the beach near where 

 the junction of the fossiliferous Tertiary beds with the Cambrian slates are seen 

 in the cliffs, only here the clay is of a deep-red colour. It is covered, uncon- 

 formably, by a very coarse river gravel. It looks as though it might have been 

 a deposit laid down in a gorge cut in the fossiliferous Tertiary limestone. No 

 base is seen to the red clay. 



The origin of the thick gravel beds exposed in the cliffs facing the sea is not 

 very apparent. They have certainly unique features and are of more than 

 ordinary interest from being related to certain physiographical conditions that 

 have long since passed away. The following points are worthy of note : — 



1. The beds do not belong to the present system of drainage. The only 

 creek that intersects the beds is the small creek, described above, but it is self- 

 evident it has had no part in building up the great gravel sediments, as it is 

 little more than a washout in these beds. The Sellick's Hill Creek flows in a 

 different direction and is of insignificant dimensions. 



2. The gravels belong to one system of deposition. They were laid down 

 horizontally throughout, in uniform layers, that can often be traced for con- 

 siderable distances, and are similar in composition throughout. 



3. Near the top of the gravels is a thick layer (up to 30 feet) of the mottled 

 clays and sands ( ? Pleistocene) containing angular and rounded stones. Thinner 

 layers of mottled clay occur a little lower down, but towards the top. These 

 are probably of a like age as the mottled beds at Hallett's Cove and elsewhere, 

 and, like the latter, are covered by a newer clay bed of a brown or greenish colour. 



4. The material of which the beds consist has evidently been derived from a 

 local source, and from a direction in which the blue limestones and the archaeo- 

 cyathidae limestones were not in the line of drainage. The latter limestones 

 occur abundantly in the creeks that flow from the ranges in a northerly direction. 

 Their absence from the gravels is rather peculiar in view of the fact that 

 siliceous quartzites form the principal feature in the beds, and the latter mainly 

 occur in outcrop behind the limestone beds. 



5. It does not seem probable that the gravels were laid down by the Onka- 

 paringa River, as the pebbles are restricted in their variety and have been laid 

 down from another direction. If they had been brought down by the Onka- 

 paringa they would have given evidence of greater wear. 



6. The height above sea level (200 feet) and the horizontality of the beds 

 indicate that at the time of deposition the land extended more to the westward. 

 No base to the gravel beds is seen except where the fossiliferous limestones occur 

 on the beach, but the latter may be an inlier of the gravels. 



7. The smallness of the average stones in the gravel represents a somewhat 

 low velocity in the transporting streams together with considerable width and 

 uniform conditions. 



