NICOL SOUTHERN GRAMPIANS. 



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mass of red and reddish-grey sandstone, with a conglomerate-bed 

 consisting of masses of brown porphyry and white quartz. The 

 strata dip at 75° to S. 45° E., and at the Falls consist of coarse sand- 

 stones below, of a quartz ose conglomerate in 

 the centre, and of deep-red, fine shaly beds 

 above. They are intersected by " backs" or 

 division-planes, nearly vertical to the bedding, 

 so that the water removing the softer portions 

 has left great square ledges projecting like 

 walls into the ravine. The conglomerate is 

 also well seen near the Railway- station, dipping 

 at 65° to S. 42° E., the whole surface being 

 deeply grooved and smoothed as by glacier- 

 action. Here also it consists especially of vein- 

 quartz, with smaller fragments of the clay- 

 slates on the north, in a reddish-brown basis 

 of decomposed felspar. Beyond the village the 

 lower sandstones, dipping at 70°-77° to S. 37° 

 E., are quarried for building-purposes, and are 

 in part fine-grained and greyish purple, in part 

 deeper brown and more shaly. 



The next formation is the clay-slate (d), seen 

 in the deep gorge of the Pass of Leny. The 

 lowest beds are light-grey greywacke, weather- 

 ing brown, and composed of distinct grains of 

 quartz in a basis of decomposed felspar and clay- 

 slate. These strata dip to N". 37° W., at angles 

 of 44° to 50°. Above them are red and yellow 

 slaty beds, some of them almost a pure iron- 

 ochre, others more arenaceous, dipping at 47° 

 to N. 17° W., but with some confusion and 

 uncertainty. Red beds follow, with a distinct 

 cross cleavage ; but their dip is disturbed and 

 obscure, probably from a dyke of blue columnar 

 dolerite, 30 to 40 feet wide, which runs N. 

 25° E. with a slight dip to the south. Beyond 

 it are fine-grained grey slates, dipping at 66° 

 to N. 55° W., but with a cross structure or 

 cleavage inclined at 20° to N. 35° E. 



At this point a marked change takes place 

 in the position of the strata. The dip is first 

 25° to N. 20° E., but soon rises to 40° to N. 

 5° W. Further on, it rises to 67°, N. 37° W., 

 and then to 75°, N. 45° W., in curved, irregu- 

 lar beds of blue slate, with a cross division 

 or cleavage inclined at 12° to N. 12° E. Grey slates again follow, 

 dipping at 68° to N. 37° W., and are succeeded by coarse greywackes 

 in thick beds, dipping at 60° to N. 5°-10° W. This rock is also 

 intersected by other planes dipping 55° to S. 2h° W., and by well- 

 marked fissures, lined on the sides by actinolite, running to W. 62° S. 



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