144 



Though the above figures represent the average case, so 

 far as exploration has yet proceeded, seams are met with of 

 much better quality than the average here stated. For in- 

 stance, at Moorlands the better quality lignite is illustrated 

 in Bores 23, 24, and 31 by seams, respectively, 13 ft., 18 ft., 

 and 16 ft. in thickness, averaging only about 7 per cent. ash. 

 At Clinton, in Bore 1, a band of lignite, 15 ft. in thickness, 

 containing less than 6 per cent, ash, is recorded; and in 

 Bore 2 there is a 15-ft. seam with 7'3 per cent. ash. 



'The ultimate relative merits of the two fields, from an 

 economic standpoint, depend upon factors far more important 

 than slight differences in composition. The shallow depth of 

 the formation, the more water-tight nature of the strata, 

 the comparative freedom from serious quantities of ground- 

 water, are all factors which favour the Moorlands area. On 

 the other hand, convenience in geographic situation for 

 marketing the fuel is favourable to the Gulf St. Vincent 

 localities. 



It is probable that, in the aggregate, great quantities 

 of brown coal will be proved, eventually, at the base of the 

 Tertiary formations in South Australia. This is most re- 

 assuring from an economic standpoint, for the mineral fuel 

 resources of the State are otherwise limited to the semi- 

 bituminous, Triassic(i2) coal of the small Leigh Creek basin. 



The best of the Leigh Creek seams (i^) averages about 

 20 ft. of coal carrying 18 per cent, ash and 20 per cent, of 

 moisture displaoeable at 105° C. Of this seam the best 6 ft. 

 averages as follows : — 



Per cent. 



Moisture lost at 105° C 32*0 



Volatile matter ... ... ... ... 26*4 



Fixed carbon ... ... ... ... 34*7 



Ash 6*9 



100*0 



This appears to be the best that the Leigh Creek semi- 

 bituminous coal field can produce as a working proposition. 

 So taken into consideration with remoteness from centres of 

 population, it is obvious that the Tertiary brown-coal forma- 

 tions are likely to be the State's mainstay in the matter of 

 fuel resources. 



(12) The occurrence of Macrotaeniopteris icianamatfae and 

 Thinnfeldia oclontopteroides in these beds fixes the age as Triassic. 



(13) yic?g Government Geologist's Report, Min. Rev., No. 27. 



