150 GEOLOGY OF THE GLENDONBROOK DISTRICT, 



they form lines of hills running in a ^general E.-W. direction. 

 These hills have a relatively steep slope on the southern side, 

 and slope more gently away to the north, showing that they dip 

 to the north in the same way as the sedimentaries do. 



This series of rocks appears to be similar to part of the Upper 

 Carboniferous Series described, some distance further to the east, 

 by Mr. J. B. Jaquet. Part of his description of the latter series 

 is: "The formation comprises sandstones, claystones, limestones, 

 tuft's, cherty shales, and intercalated lava-beds. The sedimentary 

 rocks are in part marine, and in part freshwater. The great bulk 

 of the rocks consist of coarse-grained tuffaceous sandstones, which 

 do not contain recognisable organic remains; so that one is unable 

 to determine whether they are marine or freshwater."* 



The latter part of this description might be applied equally well 

 to the series under consideration here. I have not seen specimens 

 of the Clarencetown Series, but in discussing the subject with Pro- 

 fessor David, he pointed out the great similarity, lithologically, be- 

 tween specimens of the Webber's Creek Series and the Upper Car- 

 boniferous rocks near Clarencetown. 



Another point which emphasises the resemblance to the Clarence- 

 town Series is the fact, mentioned to me by Mr. Frank Drinan, of 

 Glendon Brook, that, in the creeks in the north-eastern part of the 

 area shown on the accompanying map, the sands which accumulate 

 in the beds of the creeks often contain a notable percentage of 

 ironstone. 



No fossils have been found in this series, so that it is uncertain 

 whether they are marine or freshwater. If, however, as seems to 

 be the case, they belong to the same series as the Clarencetown 

 rocks, they are probably freshwater. 



The other series of Carboniferous rocks is developed to the south 

 of the Webber's Creek fault, and is called here the Tangorin Series, 

 on account of the bold outcrop at Tangorin Trig. Station. They 

 are bounded on the west by the northward extension of the fault 

 named, by Professor David, the Elderslee Fault. They extend as 

 far east as the district has been examined, and no doubt are con- 



*Op. cit., p. 64. 



