Geologij of Warrandyte Goldfield. 525 



observation, it might be tliought that the strueture was often 

 hopelessly tangled, but detailed examination proves that this is 

 not so. The other minor folds of the Warrandyte Anticline are 

 short and restricted to the vicinity of Warrandyte. The dips 

 along the line of dyke east of the Caledonia, and also of the 

 country further east, are all easterly with generallv a north- 

 westerly strike, thus converging towards tlie strike of the axis 

 of the second minor anticline. On the northern bank of the 

 Yarra opposite the Caledonia Mine, the dips are not too clear, 

 but so far as they go, the two converging lines of strike have 

 met here to form a single fold, with the minor folds to the 

 south and east cut out. This single fold is apparently faulted 

 to the east ; it then runs north-easterly for a short distance, 

 but soon dies out, as before mentioned. The strike of the 

 rocks however continues to the north-east. 



The structure therefore at W^arrandyte appears to be a great 

 arch, on the crown of which are several minor anticlines and 

 synclines. The two most westerly anticlines are preserved to 

 form the main axis of the fold to the north and the south. 

 This axis thus becomes disconnected at W^arrandyte. The minor 

 folds to the east of the main axis appear to merge into one fold 

 to the north of the Caledonia Mine, giving a fan-shaped struc- 

 ture, the fan opening unequally from north to south. A strong 

 northerly pitch near the river at Warrandyte has accentuated 

 the structural form. By way of contrast, the structure may be 

 considered along a line roughly parallel to the railway from 

 Blackburn to Croydon, which shows a normal order. Beginning 

 at the former place, there are, as shown on the map, the Black- 

 burn Anticline, the Tunstall Syncline," the Warrandyte Anti- 

 cline, the Mitcham Syncline. and the Ringwood Anticline, with 

 other small folds further east. The named folds are normal 

 to one another and regular, although some minor puckers are 

 found on their axes. Thus the great arch at Warrandyte be- 

 comes in its southern portion split up into five normal folds at 

 least. 



• The distinctive band of quartzitic sandstones occurs along 

 the outer part of the eastern leg of the Warrandyte Anticline, 

 and it is of interest to see how the strike runs north-easterly 

 to Croydon, then gradually swings round to the north-west, and 



