547 



= =J=oI Purple Slates 



Arenaceous Limestone 

 Bands of Quartzite 



Brighton Limestone 

 Siliceous Limestones 



paper, another explanation is given for the abnormal width 

 of the quartzite on the crest of the ridge. 



II. — The Geological Succession. 



A geological section taken across the ranges (in an east 

 and west direction) on a line between Melrose and Spencer 



Gulf, exhibits a direct 

 correspondence with the 

 beds that outcrop near Ade- 

 laide. A typical example 

 of the beds that are included 

 in the Mount Remarkable 

 section can be seen in their 

 natural order (fig. 1) along 

 a line drawn from the 

 upper slates at Mitcham — 

 a.cross the tillite of the 

 River Sturt — the limestones 

 of the Brighton cement- 

 quarries — and the purple- 

 slates and quartzites of the 

 coast at Marino. Although 

 widely separated in the 

 localities mentioned, the 

 beds in the respective areas 

 exhibit the same order of 

 occurrence and, lithologic- 

 ally, maintain a close 

 resemblance to each other 

 at their corresponding geo- 

 logical horizons. The chief 

 interest in the case of the 

 Mount Remarkable occur- 

 rences is in their tectonic 

 features and the effects of 

 earth movements, which 

 have operated on a large 

 scale. 



'o o 



Ribbon Slate 

 (Tapley's Hill Slate) 





Tillite 



Quartzites 



Slates above 

 Mitcham and 

 Glen Osmond 

 Quartzites 



~- Fig. 1. 

 Order of succession in beds near 

 Adelaide ; also at Mt. Remarkable. 



a. LOWER CAMBRIAN. 



1. Lowest (?) Beds Exposed. 



The beds which comprise the main portions of the mount, 

 as well as those on its western side, have a very constant dip 

 to the west, while those which form the foot hills on its south- 

 eastern side dip to the east. Between these respective areas 

 of opposed inclination there is a zone of shattered and 

 s2 ' 



