106 GEOLOGY OF LOWER MESOZOIC ROCKS OF QUEENSLAND, 



that it cannot be definitely decided whether they represent 

 coastal deposits on an eastern or western coast. If the boundary 

 of the true Pacific basin on the south-west be the line stated, it 

 seems more probable that they represent deposits along the 

 eastern coast of a continent. 



The evidence for the existence of the gulf, which Neumayr 

 called the Gulf of Queensland, is not very definite. 



The continued deposition of freshwater sediments in the 

 Hawkesbury basin, indicates a continuance of freshwater condi- 

 tions in this basin over a long period, and there must have been 

 some outlet, as noted above (see p. 98). As far as we know, there 

 is no possibility of an outlet to the north, south, or west, and, in 

 view of the jDresence of a foraminiferal and ostracodan fauna in 

 the upper portion of the Wianamatta Stage, it seems probable 

 that the outlet connected with an arm of the sea, such as the 

 Gulf of Queensland. The exact extent of the gulf is purely 

 conjectural. 



During the time when the Wianamatta Stage in New South 

 Wales, and the Ipswich Series in Queensland were being de- 

 posited, the Gulf of Queensland probably had its maximum ex- 

 tension in a northerly direction. At this time, there were two 

 small basins in which the Wianamatta Beds and the Ipswicli 

 Series respectively were deposited. Both these basins may have 

 had outlet to the Gulf of Queensland. Text-fig. 4 (p. 109) 

 indicates a probable distribution of land and water at this 

 time. 



In Jurassic time, there is no clear evidence to show the exist- 

 ence of the Gulf of Queensland. There are marine Jurassic 

 rocks in New Caledonia. In New Zealand, in the south of the 

 South Island, there are freshwater and marine strata of Jurassic 

 age associated with one another, indicating probably oscillation 

 of marine and fluviatile deposition in a coastal region. In the 

 North Island, in the Kawhia-Waikato district, there are marine 

 Jurassic rocks, and there are also records of fossil plants (Jurassic) 

 from the same district. This, again, indicates a probable coastal 

 region. 



