720 ME. K. H. BASTALL ON THE GEOLOGY OE [Nov. I9II, 



hills north-west of Worcester really consist of Enon Conglomerate, 

 with perhaps a thin coating of recent gravels ; but, in the absence of 

 exposures, it is impossible to decide this point with certainty, owing 

 to the before-mentioned difficulty of distinguishing between the 

 weathered Enon and the newer gravels. 



Prof. E. H. L. Schwarz T has mapped and described as Enon 

 Conglomerate a patch of gravel on the farm Lange Kloof (Geol. 

 Surv. Map, Sheet 4), east of the Hex River ; he refers to it as 

 ' an exposure of gravel, evidently very old, but of which the 

 pebbles are made of slate.' Unfortunately, owing to bad weather 

 and floods in the Hex River, I was unable to visit this interesting 

 and important exposure; but, judging from a comparison of the 

 published description with what is seen elsewhere in the neigh- 

 bourhood, I feel the gravest doubts whether this gravel is of 

 Cretaceous age, as claimed by Prof. Schwarz. The absence of slate 

 in the conglomerate at Worcester is noteworthy, and it is improbable 

 that there would be so complete a difference of composition in 

 so short a distance (less than 5 miles), especially as the Enon 

 Conglomerates of Robertson and Ashton (30 and 40 miles away 

 respectively) are exactly like those at Worcester, and contain 

 no slate. 



The small patch of Enon Conglomerate west of Robertson calls 

 for no special remark, but in connexion with the large expanse of 

 conglomerate east of the town a most important question arises. 

 On the map of the Geological Commission, on the farms De Hoop 

 and Aasvogels Nest, the conglomerate is shown, doubtfully, over- 

 lapping the fault, and resting directly upon Malmesbury Beds. If 

 correct, this observation fixes the age of the fault as between 

 Ecca and Enon, a result diametrically opposed to my observations 

 elsewhere. I therefore examined this region most critically and 

 carefully, and came to the conclusion that this mapping is unjustified 

 by the evidence. The ground is very obscure, and there are no 

 exposures in the form of excavations. 



The Malmesbury rocks here form fairly high ground, with a 

 steep slope, in fact a kind of escarpment, and on the next farm, 

 Klaas Voogds Rivier, a curious wedge of Witteberg Beds comes in 

 along the fault, and makes a conspicuous feature in the form of a 

 rocky ridge. On De Hoop and Aasvogels Nest low rounded hills of 

 gravel lie at the foot of the escarpment, and the northernmost of 

 these certainly lie to the north of the fault. But these hills do not 

 all consist of the same kind of material : the southern hills are un- 

 doubtedly Enon Conglomerate, but the hills north of the fault-line 

 consist of quite different material, without the characteristic red 

 pebbles of the Enon Conglomerate. The last hill of all, at the foot of 

 the escarpment, is different again, being composed of large blocks 



1 ' Geological Survey of the Divisions of Tulbagh, Ceres, *& Worcester' 

 10th Ann. Rep. Geol. Coinm. Cape Colony, 1905, p. 289. 



