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PROCEEDINGS OE THE GEOLOGICAL SOCIETY. 



[Dec. 5, 



the limestone, which is broken and contorted near them. The lime- 

 stone again forms the coast, intersected, however, by another N. and 

 S. line of fault at the Smoo Cave, Near Sangoe Beg the qnartzite 

 appears, forming a small wedge-shaped fragment, and is represented 

 by Mr. Cunningham, who first figured the section, as dipping con- 

 formably under the limestone*. This is no doubt its normal posi- 

 tion ; but in this place the rocks are separated by a fault and crush, 

 which has broken up the quartzite into an incoherent breccia. 

 Beyond Cnoc Garrow the quartzite is succeeded by the ridge of gneiss 

 dividing the vale of the Dionard from Loch Emboli. The ridge runs 

 S.S.W., but the strike of the beds is nearer N/W. (N. 48° W.), and 

 the dip at 70° to 85°, to S.W. or N.E. It is everywhere penetrated 

 by veins and masses of red granite and hornblende-rock, and has 

 evidently been tilted up on the west side since the deposition of the 

 quartzite, which rests in a thin and often-interrupted layer on its 

 eastern side, sloping down to Loch Emboli t. Small fragments of 

 quartzite also occur on its seaward extremity. 



This section of the Durine district is important, as proving that 

 the limestone is the highest formation in the series, and is nowhere 

 covered by higher quartzite or mica-slate ; these rocks, where found 

 in the centre of the section, being evidently brought up from below, 

 and thus underlying, not overlying, the limestone. It also shows 

 that the whole district is broken up by faults running from N.rLE. 

 to S.S.W., and that the masses of strata have generally been tilted 

 up on the west. 



Sections on Loch Emboli. — These facts serve to explain the more 

 complex sections on the east side of Loch Emboli. The first of these 

 (fig. 3) runs from near Camas-an-duin, in an east-by-south direction, 



Fig. 3. — Section of Camas-an-duin, Loch Emboli. 



W. a . E. 



d. Limestone. c 2 . Fucoid-beds. c 1 . Quartzite. 



a. Mica- and talc-slates. s. Granulite, with fragments of slate. 



across the ridge to Loch Hope. On the shore south of Camas Bay, 

 the strata are seen in their regular normal order : first the quartzite 

 (c 1 ) in curved beds, but dipping on the whole to "W. ; then (c 2 ) the 

 fucoid-beds, and above all the limestone (d),m broken irregular strata, 

 but also with a westerly dip. The limestone forms a low hill, sepa- 



* Cunningham, Geognostical Account of Sutherland in Prize Essays of the 

 Highland Society, vol. xiii. (1839) p. 97, and plate 7. fig. 4. This quartzite 

 does not appear in my former section, which runs further south than it extends. 



t Far too great thickness is assigned to this part of the quartzite in my old 

 section. Quart. Journ. Geol. Soc. vol. xiii. p. 23. fig. 4c. 



