264 T. W. EDGEWORTH DAVID. 



Hunter River Thickness Bowen Eiver Coal-field. 



Coal-field. Feet. Ius. 



f 90 (?) Chiefly dark shales, coaly in places, with 

 j ivr " I bands of sandstone. 



q . p •{ 100 (?) Sandstone flags and conglomerates. 



30 (?) White gritty sandstone resting on feis- 

 ty pathic sandstone. 



/1000 0(?) Amygdaloidal porphyrites with prehnite, 

 laumonite, and carbonate of copper; and basalts 

 and melaphyres. 



880 Yellow and white siliceous sandstone and con- 

 Khacopteris , , , , . ,, „ ... 



o j / P \ < glomerates composed ol pebbles of quartzite 



and yellow porphyry. [No fossils mentioned, 



but Mr. Jack considers these may be the 



equivalents of some portions of the Lepidoden- 



dron Series.^ 



From this section it is apparent that in the Bowen River Coal- 

 field, Permo-Carboniferous Marine strata are developed on three 

 distinct horizons, the uppermost occurring in strata, which should 

 probably be correlated with the Newcastle or Tomago Coal- 

 measures of New South Wales. Glossopteris according to Daintree 

 has been found here as low down as the basement beds of the 

 Lower Marine Series. 



(B.) Associated Eruptive Bocks. 



(i.) Contemporaneous. In the Illawarra Coal-field, as shown in 

 the section quoted, there is evidence of contemporaneous volcanic 

 activity on a grand scale, towards the close of the Upper Marine 

 Series, previous to the deposition of the Bulli Coal-measures. These 

 contemporaneous volcanic rocks consist of doleritic anclesites in 

 two sheets, separated from one another by a thick and very per- 

 sistent bed of red tuff. The upper sheet, which is quarried on a 

 large scale at Bom bah, near Kiama for road metal, is capped by 

 sheets of basalt, and these in turn are surmounted by basic volcanic 

 agglomerates, as seen at Bong Bong Mountain, near Kiama, which 

 has evidently formed one of the points of eruption. The aggregate 

 thickness of this volcanic series at Kiama, where it appears to 

 attain its maximum development, is about 1600 feet. The ande- 

 sitic lavas, as shown by Mr. C. S. Wilkinson and Professor Liver- 

 sidge f.r.s., contain laumonite in their joints, and lately Mr. 

 Cameron has presented specimens of this lava to the Department 

 of Mines, containing thin films of metallic copper in joints. 



In the Newcastle District doleritic andesites of a diabasic 

 character are also extensively developed, having a maximum 

 thickness of about 1600 feet, and occurring in two sheets separated 

 from one another by a bed of volcanic breccia. The exact horizon 

 of this series has not yet been determined with precision. It is 

 certain however that it overlies a coal seam which contains 

 Glossopteris. This seam, inclusive of bands, is nine feet thick, 



