72 



fault plan-es), with a strike W. 20° S., and this is cut off by 

 a fault that throws the quartzites against the limestone in 

 an oblique line. Nearer the foot of the range the lower beds 

 of limestone in the series occur, having a dip N. 20° E. at 

 about 25°. 



A little south of this, cut off by faulting, is a email 

 quarry in which the decomposed sandstone is seen, on one 

 side, having a dip W. 10° N. at 15°, and is thrown down, 

 on the eastern side of the quarry, with a dip E. 20° N. 

 at 75°. The strike of the fault, which cut off the Archaeocya- 

 thinae limestone, seems to have a bearing W. 20° N. The 

 -end of the limestone, where faulted, shows metasomatic change 

 to iron and manganese oxides. On the western side of the 

 fault are purple shales (greatly cbntorted), thin limestones, 

 and flags. 



The general section of the Mount Lyall Range closely 

 resembles that seen in the Parachilna Gorge, but is more 

 disturbed than the latter. 



XV. From Wirrealpa to the "Big Hill"W on the Road 



TO Blinman. 



At 4 miles out from the station (after having passed 

 over a flat of purple shales and flags, with an occasional thin 

 bed of impure limestone), the red sandstone of the scarp hill, 

 near the Wirrealpa Creek, comes down to the flat and crosses 

 the road : dip S. at 15°. The road runs on the strike of these 

 beds for a mile, then the sandstones swing round to south-east, 

 with an increase in the angle of dip, and are underlain by a 

 series of limestone bands that have an oolitic structure, which 

 measure, in the creek and sides, about 50 yards of outcrop : 

 dip E. 20° S. at 80°. These oolitic limestones are the same 

 as have been spoken of above as the Oholella limestones. 

 Within a few yards they are followed by the "ridge" lime- 

 stone, which forms a kind of rampart 12 ft. high: dip E. 

 20° S. at 65°. On the northern side of these beds, there 

 are soft decomposed flags and shales, which are perpendicular, 

 or, for a few yards, reversed, to W. 20° N., with a decreasing 

 dip, and then back again to easterly. A creek runs in the 

 form of a loop between these outcrops. 



At 6 miles out from the station there are two conical 

 hills, situated on the western side of the road, which are 

 either igneous dykes, chimneys, or (?^ sheets. The highest 

 is probably 300 ft. in height, and cor, .^ts of a dark-coloured 

 basic rock; but whilst it passes to the top of the adjoining 



(4) This is quite distinct from the ''Big Hill" which occurs 

 between Parachilna and Blinman although known, locally, by the 

 same name. 



