1 3 io AUSTRALASIA ILLUSTRATED. 



Division especially, splendid artesian supplies of good water are obtainable by boring. 



The Cretaceous gravels surrounding the Mount Brown slate ranges are being profitably 



worked for gold. The Cretaceo-tertiary series of New Zealand is extensively developed, 

 and contains valuable seams of merchantable coal. 



TERTIARY CAINOZOIC. 



Marine beds of Eocene, Miocene and Pliocene ages form a considerable extent of 

 the low-lying country of the southern portion of Australia, from Gippsland, in Victoria, 

 to Western Australia ; also in Tasmania ; they do not occur on the eastern coast of 

 Australia. But in Victoria and New South Wales, fresh-water deposits of gravels and 

 clays of Eocene and Miocene age are found containing a very interesting extinct flora, 

 corresponding with that observed in formations of the same age in the Northern Hemi- 

 sphere. Fresh-water Pliocene deposits, with characteristic fossil plants, are also frequent, 

 especially in New South Wales and Victoria. In New Zealand the Tertiary fresh-water 

 and marine series are well represented. 



POST TERTIARY. 



Pleistocene and Recent. Deposits of these periods occur abundantly upon the coasts 

 and inland. The loam deposits of Australia forming the vast inland plains, and the 

 terrace gravels and alluvial flats in all the main valleys, are chiefly of Pleistocene age, 

 and, together with the cave deposits, have yielded numerous remains of extinct animals, 

 some of which, as the Diprotodon, Nototherium, Notiosaums, Megalania, Dromornis, etc., 

 were of gigantic size. With them have been found bones of animals of species now 

 living in the same localities. The Pleistocene period was one of great rain-fall, and 

 during it small glaciers were formed upon some of the highest mountains of the Great 

 Dividing Range, as on Mount Kosciusko. Glacial strife have been observed upon some 

 of the schist rocks near Adelaide. Human remains have as yet been found only in the 

 recent alluvia. The remarkable gigantic wingless birds of New Zealand became extinct 

 during the Recent period. 



The Tertiary and the Post Tertiary fresh-water deposits are of the highest economic 

 importance, for they have yielded by far the greater portion of the gold and stream tin 

 hitherto raised in Australia. In New South Wales about 50,000 diamonds have been 

 obtained from these deposits. Extensive areas of sand-hills, formed by wind-action, occur 

 over many portions of the Continent and give rise to barren country. 



IGNEOUS AND METAMORPHIC ROCKS. 



Igneous rocks occupy a very considerable area in Australasia. They comprise a 

 great variety of granites, porphyries, greenstones, basalts, etc., some of which pass by 

 such a gradual change from one into the other that it is often impossible to draw any 

 definite line of division between them. On the other hand, some of them change so 

 gradually into rocks of a sedimentary origin, as, for instance, granites into Silurian schists, 

 that they afford convincing proof of their metamorphic origin. 



Dykes of intrusive granite occur, penetrating Lower Silurian strata in Victoria, and 

 Triassic beds in New South W r ales have been intruded by hornblendic granite. No 



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