Harry Page Woodward — Geology of Western Australia. 545 



the west side of the Eden valley, and abutting against the high ground 

 of the east side of the Lake District. This ice would (according to 

 the strige and the distribution of the boulders) have taken the exact 

 direction required in order to form the temporary dam. 



6. Unless the above explanations be proved erroneous, it is 

 unphilosophical to advocate a great submergence to account for 

 the phenomena, a submergence to which other phenomena seen in 

 the neighbourhood are in direct opposition. 



Ill, — Notes on the Geology of Western Australia. 

 By Harry P. Woodward, F.G.S., F.R.G.S., Governmeut Geologist, Perth. 



AS Western Australia is attracting considerable notice on account 

 of the recent rich gold discoveries, a short paper upon its 

 geological formations may be of intei-est. 



Eegarded as a whole. Western Australia is not an interesting 

 field for geological research, at any rate from a stratigraphical 

 or pal aeon tological point of view, for, with the exception of one or 

 two districts in the north, all the rock-outcrops are either granites, 

 crystalline schists, or volcanic dykes. 



Physical Features. 

 Although surrounded on three sides by the ocean, the coast-line is 

 comparatively short, being only about 3,500 miles to the superficial 

 area of 976,000 square miles. It is low and uninteresting on the 

 whole, being destitute of bold headlands ; the shore is either flat and 

 little above the sea-level, or when cliffs do occur, they rarely exceed 

 an elevation of 100 feet. These cliffs appear mostly where the 

 escarpment of the table-land, which extends into the interior, has 

 been cut off abruptly by the sea. That the coast has been elevated 

 in recent times is proved by numerous raised beaches— low shelly 

 limestone-cliffs, containing remains of existing species of mollusca, 

 etc., and by large deposits of dead marine shells in the estuaries of 

 the rivers upon the south-west coast. Upon the southern portion 

 of the coast there is very little rise and fall of tide, but to the 

 northward of North-west Cape it is considerable (being 46 feet in 

 King's Sound), the constant alteration of sea-level playing an 

 important part as a denuding agent along the coast and inlets. 



The interior is most accurately described as a low, gradually- 

 rising table-land with no bold ranges, the highest hills in the 

 colony not exceeding 4,000 feet above the sea-level. There are no 

 navigable rivers, and with the exception of a few in the South-west 

 (which are always running) they are only immense storm-water 

 channels. 



The so-called lakes of the interior are large salt-marshes or clay- 

 flats, being, in fact, the upper courses of the rivers where there is 

 but little rainfall, and the country is so level that the water spreads 

 out over the flats, where, except in very wet seasons, it evaporates, 

 leaving a deposit of mud and salt behind. 



There are no active volcanoes, but large lava-flows exist, and 

 extinct craters are said to have been met with. 



DECADE IT. VOL. I. NO. XII. 



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