Mary River, Queensland. 77 



as there are various known Auriferous localities along the ranges 

 between the Burnett River and Moreton Bay. 



The Brisbane River and the Mary rise in an extension of the 

 great Bimya Bunya Range, which sends down its spurs north and 

 south, forming deep channels of drainage between them. These 

 spurs do not belong to the main Cordillera which is there known 

 as the Bunya Bunya Range, and trends north- westwardly, having 

 however, its gold patches as well as the meridional ranges that 

 diverge from it in direction along the Mary. 



The whole of the broken region forming this area is composed 

 of rocks eminently characteristic of an Auriferous district. And 

 those who have studied the structure of such a district in New 

 South Wales could not fail to anticipate the finding of Gold some- 

 where along the Mary. 



Granite and Syenite, with other Hornblendic rocks, form the 

 base of the system, supporting Chloritic, Talcose, Micaceous, and 

 other Slates traversed by Quartz lodes, and showing on their 

 flanks various members of the Carboniferous formation ; such as 

 Conglomerates and Sandstones above, succeeded by Coal and 

 marine fossiliferous beds (as in New South Wales) on the lower 

 portion of the river ; good coal, in a thick seam appearing on 

 Harvey's Bay, not far from the mouth of the Mary. 



Besides the rocks before named, Diorites of various kinds form 

 prominent summits, as at Boople, on the Range forming the 

 easternmost boundary of the Ubi Ubi and Mary, and along the 

 Bunya Bunya and branch Ranges. 



This rock, by the way, is nearly identical in composition with 

 that which forms the old Dioritic bluff at the south-western ex- 

 tremity of Prospect Hill, near Parramatta, having some of its 

 varieties more like the rock of the bluff at Bowrell, or Gibraltar 

 Gap, above the Pitzroy Railway Tunnel. 



Basalt and Serpentine, with some Porphyry and Trachyte, also 

 occur along the Mary (as at Widgee Widgee) and on the Brisbane, 

 and north and south of their sources. 



At Kalkiven, about thirty or thirty-five miles west of the Mary 

 the slates are traversed by quartz reefs holding gold and copper, 

 the proportion of the former being considerable. Iron ore 

 also abounds in this region. The mineral district of the Mary is, 

 therefore, one of considerable promise. 



Probably from the physical features of this broken country, 

 there are few wide tracts for the working of alluvial gold, which 

 must be patchy ; but so far as geological indications go, there is 

 an extraordinary combination of such features as characterise a 

 well-developed Auriferous region. 



Mr. Davidson, the Gold Commissioner, reported on the 28th 

 October, just nine days ago, that out of a small water channel in 

 a ridge of Diorite strewn with quartz-drift, three men had col- 

 lected in the preceding week, 180 ounces of gold. 



