BY T. GRIFFITH TAYLOR. 



519 



The question of the origin of the above land-forms next arises. 

 The chief contours have undoubtedly arisen since Carboniferous 

 times. The coal measures were laid down in a huge geosyncline 

 due to earlier folding, possibly in Carboniferous times, since such 



Table Showing the 



Strata involved. 



Age. 



Name. 



rillCKNESS. 



Character. 



Position. 



Palaeozoic. 











Permo-Car- 



Lower 



5000 



Shales and 



Constituting por- 



boniferous 



Marine 



feet 



sandstones 



tion of the outer 

 margin of the 

 eroded geosyn- 

 cline. 



do. 



Greta 

 Series 



130 



Coal and 

 shales 





do. 



Upper 



5000 



Shales, 



\ 





Marine 





sandstones, 

 mudstones, 

 etc. 



The peripheral 



outcrop of the 



\ Coal Measures 



do. 



Newcastle 

 & Tomago 

 Measures 



2500 



Coal and 

 shales 



consists chiefly of 

 these Measures. 



Mesozoic. 











Triassic 



Hawkes- 

 bury 

 Series 



2500 



The upper 

 thousand 

 feet of 

 hard sand- 

 stones 



A layer protecting 

 the central por- 

 tions of the Coal 

 Measures from 

 denudation. 



phenomena seem to have been world-wide at that period. From 

 fig. 2 we see that this syncline, trending N.N.W., extended at 

 least from Ulladulla to Gunnedah (the present northern boundary 

 being somewhat oblique), and thence to the coast near Port 

 Stephens. 



