﻿250 



■REV. W. HOWCHIN ON GLACIAL BEDS OF 



[May 1908^ 



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skirting the Mount - Lofty- 

 ranges, became covered with 

 freshwater and estuarine de- 

 posits, which are now at con- 

 siderable elevations. About 

 7 miles south of Adelaide, a 

 deep gorge of the Sturt River 

 (PL XX) dissects this Miocene 

 plateau, which is from 800 to 

 1000 feet above sea-level, and 

 exposes the Lower Cambrian 

 beds in excellent sections. 

 The glacial series form the 

 leading geological features of 

 the Sturt Yalley, and may 

 here be conveniently studied 

 with respect both to their 

 upper and their lower limits, 

 as well as their lithological 

 characteristics. The high 

 angle of cleavage in the beds, 

 together with the undermin- 

 ing action of the stream, has 

 exposed immense faces of 

 rock, which afford striking 

 sections of the till, rising in 

 steep terraces for several 

 hundred feet on each side of 

 the valley. 



The river cuts obliquely 

 across the strike. The junc- 

 tion of the till with the over-^ 

 lying Tapley's - Hill Slates 

 follows the south-western 

 bank of the stream, on the 

 western side of the outcrop ; 

 while the base of the glacial 

 series is seen on the eastern 

 side, in a strike nearly due 

 north and south, and is in- 

 tersected on that side by the 

 Adelaide & Melbourne Rail- 

 way. Railway - cuttings in 

 the glacial beds occur, from 

 a little east of the viaducts 

 to the Metropolitan Brick- 

 "Works, near Blackwood, 

 where the glacial clay (by 

 excluding the bigger erratics 



