92 



found in the plains between the sand-ridges consist chiefly of 

 this material, having in this state a thick coating of ferruginous 

 matter. 



Conglomerates were found on several of the aforesaid terraces. 

 The component pebbles consist of quartz rock and lydite, and 

 seemed to be consolidated only in a slight degree, as they were 

 seldom encountered cemented together, but lying loose, and 

 covering the base of the rises. 



The indurated clay was found covering argillaceous sandstone 

 in one place. The thickness of the stratum, however, seemed to 

 be limited as far as the covering sands would permit of exami- 

 nation. 



A mudstone occasionally cementing together the rubble of the 

 underlying rooks, and found surrounding the water holes near 

 Camp 40 and Camp 44 is of a secondary fresh-water formation, 

 and of no intrinsic value. 



Well aware of the insufficiency of ranging a series of sedi- 

 mentary rocks under a certain geological formation only on 

 account of the lithological character, as it was done in this case, 

 it must be acknowledged that the lithological and stratigraphical 

 features of the Mesozoic (Cretaceous) formation are in agreement 

 with those of the typical area in Australia. Moreover they 

 resemble the Cretaceous deposits met with in the early part of 

 our journey, which have been proved to be of that age by means 

 of fossils. 



Ill— PAL/KOZOIC. 



Their first occurrence was between Camp 5,3 and Camp 5.5, 

 and the second occasion towards the end of tliis part of the 

 journey, when approaching the Eraser Range. 



The PaliBozoic rooks at the first-named spot formed a moderate 

 high line of hills of a distinct north-east and south-west trend, 

 the dip being 70° to 80° south (see fig. 8, pi. 4). Where this 

 formation was traversed it was about 25 miles wide, the greatest 

 breadth, however, seemed to be east and west with the trend of 

 the hills. They consisted of garnetiferous gneiss, mica schist, 

 pegmatite, and a breccia of the rubble of these rocks cemented 

 by a siliceous material. The last is of course of secondary 

 formation only. 



There is not much to say about the lithological character of 

 these rooks, but as regards their occurrence in this latitude they 

 are of some interest. 



As it has been demonstrated by Professor E. Tate in his report 

 on an exploration into the Bunda Plateau, the older Tertiary 

 deposits of this region rest on a Pakeozoic basin, whose pro- 

 tuberances emerge above the overlying Tertiaries as far as can be 

 seen at Yatala, Fowler's Bay, Pedinga, Ooldea, and Boundary 



