Reviews—Geological Survey of Western Austraha. 89 
V1I.—Geuotoercat Survey or Western AvsTratia. 
ULLETIN No. 35 (1909) consists of a well-illustrated report on 
the Gold and Copper Deposits of the Phillips River Goldfield, 
by Mr. Harry P. Woodward, with notes on the crystalline rocks by 
Messrs. E. 8. Simpson and L. Glauert. The district les near the 
south coast, with a port about 150 miles east of Albany, and in 
geological structure it is a complex of schists and serpentines, granites 
and areenstones, together with some probably Tertiary sandstones, 
quartzites, and conglomerates, and various superficial deposits. The 
crystalline rocks are much decomposed, in places to a depth of nearly 
100 feet, and the lodes, with few exceptions, have at present been 
worked only above the ground water-level. The lodes comprise 
(1) basic cupriferous dykes, and (2) siliceous and ferruginous deposits, 
which appear to fill channels along rock-joints. The conclusions 
drawn are that the cupriferous dykes are of sufficient size to warrant 
deep mining, but that gold and silver will then occur in negligible 
quantities. The siliceous and ferruginous deposits give less promise 
of permanency, but they usually carry fairly high gold and silver 
values, and have been classed as auriferous lodes, copper, when 
present, being in small quantities. In some instances, however, with 
increasing depth, the gold is greatly diminished, and copper ore 
becomes dominant. It is noted that primary sulphides occur in the 
rocks above the ground water-level, and the explanation given is 
that the great density and impermeable character of the matrix have 
protected the ore, in these cases, from the oxidizing influence of 
descending aerated water. The ores worked during the past eight 
years have yielded on an average 4 per cent. of copper and half an 
ounce to the ton of gold. 
VII.—ScutucHTen AUF DEM Pema Tscuoxusu. By, ALEXANDER 
Iwrscuenxo (of Kiev). {The Ravines of the Tschokusu Plateau. | 
Ann. géol. ef minéral. de la Russie, Novo-Aleksandria, vol. xii, 
livr. 1-11, pp. 19-26. 
FJ\HIS paper sets forth the results of the investigations carried out 
by the author during a second excursion to the southern portion 
of the Tschokusu Plateau in the summer of 1908. ‘The district is eut 
out into terraces, the southern margins of which are broken into by 
ravines. These ravines widen considerably, and often form cauldron- 
shaped expansions in their upper reaches ( Oberldufe), while the lower 
reaches become narrower. ‘The terraces undoubtedly represent the 
results of the drying-up of the Aral basin. Their relative size and 
slope point to intermittent recession of the sea, the periods of non- 
recession corresponding to the time when the terraces were formed. 
The ravines were formed contemporaneously with the recession of the 
sea, the upper reaches having originated at an earlier period than 
the narrower lower reaches. From the nature of the denudation the 
T'schokusu Plateau belongs to the same category as the district of 
Barsukow ; both are characterized by desert conditions. 
The article is accompanied by three photographs and two diagram- 
matic illustrations. 
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