77 



part into numerous thin beds. The stone is fine-grained and 

 light-colored, and, where seen from a distance, its blanched boul- 

 ders present the appearance of a limestone outcrop. The beds 

 are folded into acute anticlinal and synclinal curves, the major 

 anticlinal being about 500 yards in diameter where intersected 

 by the road. The strike of the beds is E.N.E. and W.S.W. 

 Dip S.S.E., nearly vertical. 



II. Calcareous Group, including the following sub-divisions — 



(a) Crystalline Marbles. — Near a sharp elbow of the road 



white and cream colored marbles are seen to rise 

 from beneath the quartzites. These light colored, 

 saccharoid marbles have a close resemblance to the 

 " Ardrossan Marbles " of Yorke's Peninsula. 



(b) Earthy Shales. — For the distance of half a mile the 



road runs closer to the line of strike, and passes 

 obliquely over a succession of alternating earthy 

 shales and limestones, the latter varying from a blue 

 siliceous limestone to an earthy, flaggy limestone. 

 Where the laminated earthy shales attain any con- 

 siderable thickness they are generally crushed and 

 flexured. 

 ,(c) Black Impure Limestone, with much earthy matter 

 irregularly distributed throughout the mass, the 

 siliceous portions weathering into brown patches and 

 streaks on the face of the stone. 



(d) Flaggy limestones. Dark-coloured limestones and earthy 



partings, regularly alternating in bands about one 

 inch in their respective thickness. Outcrop serrated 

 and very distinctive. Estimated thickness, 500 feet. 

 Is persistent over many miles of outcrop. Dip, 70° 

 to 76° E.S.E. 



(e) Archceocyathinm marble. Grey to bluish limestones and 

 marbles, outcropping in large tabular masses, often 

 level with the sward. Chiefly composed of Archceo- 

 cyathincB corals. Thickness about 100 feet. 



(f) Impure limestone, more or less siliceous and earthy, in- 

 cluding a thin belt of flaggy limestones, resembling 

 (d). 



(g) Compact blue limestone. Locally known as " blue metal," 

 and has been quarried in a small way for lime-burn- 

 ing. Sparingly fossiliferous, carrying small mollusca 

 and occasional Archceocyathince. Several hundred 

 feet in thickness. 



III. Argillites. Grey, purple, and black argillaceous shale, 

 which in places becomes more or less calcareous. Strongly 

 jointed, breaking up into numerous rhomboid prisms. The stone 



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