446 T. W. E. DAVID AND E. F. PITTMAN. 
Measures of New South Wales together with their associated 
marine strata :— 
"eee , Upper Coal Measures or Newcastle Coal Measures. 
Middle Coal Measures or East Maitland Coal Measures. 
Upper Marine Series. 
Carboniferous « Lower Coal Measures or Greta Coal Measures. 
Lower Marine Series. 
With regard to the relation of the Illawarra Coal Seams to 
those of Newcastle, Mr. C. 8. Wilkinson, the late Government 
Geologist, wrote in 1887,* that in his opinion the former belonged 
to the series below the Newcastle beds, probably to the Lower 
Coal Measures, that is to the Greta Coal Measures. Mr. Wilkin- 
son was led to this provisional conclusion from a consideration of 
the fact that kerosene shale had been proved to occur in the Greta 
Coal Measures alone out of the three sets of coal measures developed 
in the type district, that of the Hunter River, and he thought 
therefore that as kerosene shale had been proved to exist there and 
also at America Creek, Mt. Kembla, in the Illawarra Coal-field, that 
the two deposits occupied an identical horizon. This inference 
appeared to be corroborated by the fact that at the head of the 
Clyde River some coal measures, at first considered to be the 
equivalents of the Illawarra Coal Measures, were found to be 
capped by marine strata similar to those covering the Greta Coal 
Measures, and also to contain a seam of kerosene shale. 
A subsequent examination however by Mr. Wilkinson of the 
Clyde Coal Measures in the southern extremity of the Illawarra 
Coal-field, while it convinced him of the probable identity of these 
measures with those of Greta, proved at the same time that the 
Clyde Measures were quite distinct from the Illawarra Coal 
Measures at Mt. Kembla, and the fact was thus established that 
in the Permo-Carboniferous strata of New South Wales there 
existed at least two distinct kerosene shale horizons. 
The question still remained to be settled as to whether the 
Illawarra Coal Measures were a continuation of the Newcastle 
* Mineral Products of New South Wales, etc., Department of Mines— 
Government Printer, Sydney 1887, p. 68. 
