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apex of the fold, and some have been traced continuously 

 around the end of the dome from one limb to the other. 

 But generally, the outcrops of veins form only small 

 portions of elliptical curves, and these are most frequently 

 arranged en echelon so that they lie in zones radiating 

 from the centre of the dome and diverging more or less 

 from the major axis according as the fold is broad or 

 narrow. These zones are on those parts of the dome 

 where the strata do not strike approximately parallel 

 with the axis of the fold but curve towards the axial line. 

 In symmetrical domes, like that of Oldham, there may 

 thus be four zones, and these four zones may be considered 

 as merging into one another so as to favour the formation 

 of veins, the outcrops of which form almost complete 

 ellipses. In most districts, however, there are only two 

 zones of veins, as at Waverley where they may be regarded 

 as merging into one to form saddles; and in some districts 

 there is only one zone, as at South Uniacke. 



In some districts the formation of veins seems to have 

 been dependent on small subordinate folds or flexures. 

 In some places there is a curving of the main axis of the 

 fold and in such cases veins are found to be much more 

 numerous and auriferous on the convex side of the axis. 

 In some domes there is a torsion or twisting of the fold 

 adding to the complexity of the structure and occurrence 

 of the veins. 



Mining operations in several districts have shown that 

 underlying the veins exposed at the surface are other 

 parallel interbedded veins. Each district has thus a vein- 

 bearing zone with a horizontal extent determined by the 

 outcropping veins and with an indefinite vertical extent. 

 In its vertical extension each zone is believed to be roughly 

 parallel with the axial plane of the anticline. The distance 

 of the exposed veins from the axis depends on the dip 

 of the strata, and it is probable that the distance from the 

 axial plane of any portion of the zone of veins extending 

 into the earth is also dependent on the dip; if the fold 

 gets sharper with depth, the zone of quartz veins probably 

 approaches the axial plane, or if it flattens with depth, 

 the zone of auriferous veins recedes from the axial plane. 



Most of the veins lie in slate beds varying in width from 

 a fraction of a foot to a few feet. Rarely they lie in the 

 middle of the bed and, as a rule, only when the bedding is 

 marked by some difference in composition or texture, 



