48 



ME. J. A. DOUGLAS ON GEOLOGICAL SECTIONS |>ol. lxxvi, 



Quencha, beds of white quartzite, dipping 20° north-north-east- 

 wards, are seen cropping out on the right of the vallej'. They 



Fig. 5. — Geological sketch-map of the Viscachani Valley, show- 

 ing unconformity of Carboniferous Limestone on older 

 Palaeozoic rocks. 



[Approximate scale, 1 : 4000.] 



1 & 3 = Olive-green quartzites. 2 = Black shales. 4 = Purple limestone 



with Zaphrentids. 5 = Grey limestone. 



show no signs of the intense crushing exhibited by the under- 

 lying rocks ; and, although the actual junction of the two is not 

 visible, it is obvious that they are of later date than these. The 



