NEW SOUTH WALES COAL FIELDS. <J3 



The Lower or Greta coal measures occur between West 

 Maitland and Greta. There are two seams worked in these 

 measures, viz. : 



The Upper seam, varying between 14 and 32ft. thick. 

 The Lower seam, varying between 3 and lift, thick. 



The average aggregate thickness of coal in these measures 

 has been estimated at about 20ft. The Greta seams are some- 

 times inclined at a considerable angle, as at East Greta, 

 where the dip is 45 degrees. 



The Lower coal-measures have been recognised in the 

 extreme southern portion of the Illawarra coal-field ; but so far 

 as prospected the seams do not appear to be workable under 

 present conditions. 



The Ashford coal-field is a long narrow field, about a 

 quarter of a mile wide, north of Inverell, which appears to 

 belong to the Greta coal measures. It contains a 27ft. thick 

 seam, which dips at a high angle, and is much disturbed. 

 The quality of the coal appears to be good, but owing to the 

 field being in a somewhat remote part of the State, and not 

 connected with a railway, it remains unworked. 



The Carboniferous coal measures occur in the neighbour- 

 hood of Stroud ; the coal is, however, very inferior and of no 

 Talue. 



The total contents of the New South Wales coal-fields of 

 Palaeozoic age has been variously estimated by different 

 Authorities. The late Government Geologist, C. S. Wilkinson, 

 gives it as 78,000,000,000 tons of exploitable coal, in seams 

 not less than 2?,ft. thick, within a depth of 4000ft., a deduction 

 of one-fifth being made for waste in the getting, etc. Accord- 

 ing to Prof. T. W. E. David,* in the gross quantity of co-d, in 

 seams not less than 3ft. thick, and within a depth not greater 

 than 4000ft., there are between 130,000,000,000 and 

 150,000,000,000 tons. Mr. E. F. Pittman,t the present Govern- 

 ment Geologist, reckons there are at least 115,000,000,000 tons 

 of available coal, after deducting one-third of the gross quan- 

 tity of the coal for waste in getting, etc. 



Professor David, who has made a special study of the New 

 South Wales coal-fields, considers! that as the coal in the 

 Oremorne bore, near Sydney, dips west at the rate of 110ft. 

 per mile, while the seams in the Blue Mountains dip east at 

 the rate of about 90ft. per mile (Fig. 28) the centre of the 



* Australasian Association for the Advancement of Science, 

 1890, Vol. II., p. 461. 



tMineral Resources of New South Wales, p. 322. 



t Summary of OUT Present Knowledge of the Structure and 

 Origin of the Blue Mountains of New South Wales, Jour. 

 Hoy. Soc. of N.S.W. (1896), xxx., 33. 



