

GEOLOGICAL RECONNAISSANCE OF THE STIRLING RANGES. 101 



the quartzite layers from west to east to the extent of 

 about three feet, and has caused a cleavage in the phyllites 

 dipping east at 27°. On the southern flank of Magog the 

 <lip of the ripple marked quartzite is east 30° south at 15°. 

 In the southern peak of the twin summits the inclination 

 is in the same direction, but with angles up to 30°. The 

 rapid steepening of the dip at this point suggests either a 

 very sharp anticline or more probably another line of fault 

 transverse to the axis of the range. If this exists, it is 

 probable that the low depression west of Magog, and The 

 Pass have both been determined by transverse lines of 

 weakness. 



In the summit portion of Peak Barnett the beds appear 

 to dip a little west of north at about 20° (estimated from 

 a distance). The low north-western outliers of the range, 

 near which the road passes, all seem to have slight scarps 

 towards the north with long gentle dip slopes towards the 

 south. 



In the neighbourhood of Mondurup there is an area of 

 very considerable disturbance. About half way between 

 Redgum Spring and the mountain the ripple marked 

 quartzite dips south 19° west at 19°. On the western 

 slope of Mondurup itself the dip is south 35° east at 17°. 

 About half way up the slope there is a very conspicuous 

 outcrop in which the dip is due south at 44°. Still higher 

 up tremendous contortion of the quartzite is to be noted. 

 In the western summit of the ridge, where the heavy 

 quartzite beds are exquisitely ripple marked, the dip is 

 south 17° west at 48°. In the saddle slightly to the south- 

 east of this summit there is a local twist giving rise to a 

 strike trending north 72° east with a vertical dip. On the 

 whole then, the rocks of this mountain exhibit moderately 

 ste^p inclination in a general southerly direction. The 

 main axis of the great hog-back which forms the mountain 



