ABSTRACT OF PROCEEDINGS. XXXI. 



the peripheral portion of the Continent. The continent of Aus- 

 tralasia does not appear to have been affected by strong folding 

 movements in Post-Pal seozoic times, nevertheless powerful folding 

 movements, both of Mesozoic and Tertiary age occurs along curves 

 sympathetic with the periphery of Eastern Australia. These 

 features traverse the longer axes of New Guinea, New Caledonia 

 a,nd New Zealand. The latest movement of uplift which affected 

 the areas under consideration appears to have been one of an 

 eperiogenic nature, probably late or Post-Tertiary in age. It was 

 of differential nature, the amount of vertical movement becoming 

 increasingly great, in a direction as from south-west to north and 

 east. Thus there are three plateaux existent, separated by two 

 negative areas, namely, the Great Western Plateau with an aver- 

 age height of little more than 1,000 feet in the south-west ; an 

 Eastern plateau varying from 1,700 feet to 7,300 feet high, and 

 farther north and east a New Guinea plateau reaching a height 

 of 15,000 feet, and a much dessicated plateau in New Zealand 

 reaching a height of 12,300 feet. 



The Australian plateaux are separated by the central plains, 

 and these in turn are separated from the high New Guinea and 

 -New Zealand examples by the deep Coral and Tasman Seas. 



A remarkable story is revealed also by a study of the mineral 

 distribution in Australasia and associated regions. Two only are 

 selected here for mention, namely, the gold and tin-wolfram-molyb- 

 denite-bismuth groups. The gold deposits in West Australia 

 appear to be of Pre-Cambrian age. In the great belt running 

 through West Tasmania, Bendigo, Ballarat, Cobar, Canbelego, up 

 to a point where it disappears under the great plains, the gold is 

 commonly in 'saddles,' and of an age which may be closing Ordo- 

 vician, Silurian, or Devonian. Immediately east of the great 

 Hunter zone of weakness, the gold veins are closing Carboniferous 

 in age, according to Benson, while the goldfields east and north 

 of them appear to be closing Palaeozoic in age. The Hauraki gold 

 deposits in New Zealand are cited as late Tertiary in age, but 

 unlike the older groups, they do not appear to be associated with 



