Geology 



there had been a forest fire here about three years 

 previously, it was not very difficult to make our way 

 across. 



Arrived at the fall, we found that, as we suspected, it 

 was caused by the Black Point Dyke, the waters of the 

 Red River having been unable to cut through the hard 

 basalt as rapidly as through the soft red sandstone by 

 which it was flanked. The fall was approached from 

 below by a short gorge, the lower part of which was cut 

 in sandstone, but the fall itself was over the dyke, 

 though the waters had already cut part way through it. 



FIG. 1 8. Section of Waterfall, a, Keuper Sandstone ; , Basalt. 



The junction of the sandstone with the basalt was well 

 seen, but there was little alteration of the former along 

 the line of contact (Fig. 18). 



At the foot of the fall was a deep pool into which the 

 waters fell, and whose lower lip was formed by a bar 

 consisting of large boulders of basalt, which had been 

 broken away from the dyke and piled up by the action 

 of the plunging water. 



An old mineral prospector, now in the employ of the 

 Brick Company, informed us that the exposures of the 

 Keuper Marls were much more extensive on the farther 



side of the Hutton River, and a visit to this region 



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