BY A. B. WALKOM. 147 



« 



The Coal-Measures at Westbrook Creek were reported on by the 

 late C. S. Wilkinson,* and also have been examined by Professor 

 David, f 



The ironstone at Westbrook Creek has also been mentioned in 

 J. B. Jaquet's memoir on "The Iron-Ore Deposits of New South 

 Wales."} 



Physiography, etc. — The knot of hills round Mt. Tangorin is 

 composed of hard resistant rocks, mostly eruptive, of Carboni- 

 ferous age. Similar rocks are also responsible for the range which 

 trends about E.N.E. from Tangorin, although they do not form 

 the summit of the range at all points. A part of the top of the 

 range, for a distance of about 2 miles E.N.E., from portion 96, 

 Parish of Stanhope, is made up of massive conglomerates and 

 sandstones of Upper Marine age. These sandstones and con- 

 glomerates extend northwards nearly to the southern boundary of 

 portion 90, Parish of Tangorin, and form a number of flat-topped 

 hills. Less resistant rocks (of Lower Marine age) intervene between 

 these conglomerates and sandstones and the Carboniferous rocks, 

 and the denudation of these is responsible for the gap in the range 

 at Cranky Corner. To the west of Brook's Mountain, the country 

 becomes undulating. The rocks in this part belong to the Upper 

 Coal-Measures and Upper Marine Series, which have been let down 

 to the level of the Carboniferous rocks by heavy faulting. 



A point worthy of note is the salinity of the creek-waters in the 

 neighbourhood of the Tangorin Range. This is brought to one's 

 notice, during dry weather, by the fact that the gravels and creek- 

 beds are often covered with a white saliferous deposit, when there 

 has been a good deal of evaporation. 



General Geology. — Stratigraphically/- the rocks represent two 

 systems, (A) Carboniferous, and (B) Permo-Carboniferous. 



(A) Carboniferous. — There are two distinct divisions of the 

 Carboniferous rocks, separated from one another by the Webber's 

 Creek fault, which extends in a general E.-W. direction for about 

 10 miles, and throws to the south. 



* Ann. Report Dept. Mines N. S. Wales, 1884, p. 151. 



■fOp. cit. y pp. 274-277. 



£Mem. Geol. Survey N. S. Wales, Geology, No.2, 1901, p. 111. 



