Art. III. — TJte Relations of the Granitic and Lower 

 Palaeozoic Rocks near Dandenong. 



By IAN M. SUTHERLAND 



(Communicated by Professor J. W. G-regory, D.Sc, F.E..S.). 



(With Plate X.). 



[Kead 12th May, 1904.] 



I.— Object. 



The granites of Victoria are of two ages ; one granite is pre- 

 silurian, and the other was intruded in the earlier part of the 

 devonian age. Mr. A. W. Howitt writes •} " Tlius, leaving out 

 of the question those rocks which are clearly felsites, it becomes 

 evident that there are in North Gippsland two distinct classes of 

 granites. The older are truly granitic in character, and frequently 

 hornblendic as well as micaceous ; the younger approach nearer 

 to the felsites, and, so far as I am aware, are not only poor in 

 mica, but also quite without hornblende. The older granites may 

 approximately be placed at the close of the silurian, and the 

 younger granites in the earlier part of the devonian age. There 

 seem therefore to be grounds for the statement that, so far as our 

 present knowledge extends, the devonian granitic rocks of North 

 Gippsland have a peculiar character wherever met with ; Init in 

 this it is necessary to guard strongly against the supposition that 

 no true granites may have been formed in that age." 



In memoirs of the Geological Survey of Victoria, in an 

 appendix to the Report on the Chiltern Goldfields, by 

 Stanley B. Hunter, page 42, Professor Gregory writes : 

 "Mr. Howitt long since suggested that the granitic rocks of 

 Victoria belong to two distinct groups. Those of one group 

 were intrusive in devonian times. The earlier group was pre- 

 silurian. It has been the custom to regard the great majority 

 of the Victorian granitic rocks as belonging to the devonian 

 group." 



1 Report of Proj^ress of the Geological Survey of Victoria, 1877. Notes on the Geology 

 of Part of the Mitchell River Division of the Mining District of Gippsland, p. 121. 



