Art. III. — O71 certain Conglomerates near Sydenliani. 



By T. S. hart, M.A., F.G.S. 



(With Plate IX.). 

 [Eead 9tli April, 1903.]. 



Among the older rocks exposed along the deep valleys of the 

 Saltwater River and Deep Creek, across the Keilor Plains, there 

 occur certain conglomerates. Apart from the rarity of conglom- 

 erates among these rocks, these present certain features of 

 interest. 



This portion of the course of the above-mentioned streams 

 is within the area mapped in Quarter-sheet 7 S.E., extending 

 through 2 S.W. into 1 N.W. 



The positions of the conglomerates are denoted by the numbers 

 1 to 7 on the accompanying map. Of these, Nos. 1 and 3 are 

 unnoticed on the Quarter-sheets, Nos. 5 and 6 are indicated by 

 the symbol "C3," but I failed to detect them when going along 

 those parts of the valleys. No. 7 I have only seen on the river 

 bank at the place at which the number is placed, but it is shown 

 on the Quarter-sheet as far north and south as the crosses on the 

 locality map. 



Description of the Observed Conglomerates. 



The locality 1 is about a mile and a half from Sydenham 

 Railway Station, and close to the fifteenth milepost on the 

 Mount Alexander Road. The right bank of the Saltwater on 

 this bend rises in a steep cliff. At the western end of this cliff 

 are mudstones and sandstones of ordinary character dipping 

 easterly at 70° to vertical or slightly overturned. These are 

 succeeded by mudstones with pebbles scattered through them in 

 various positions, isolated, or in patches, or somewhat in bands. 

 The pebbles are well-worn, but frequently flat-sided, some present 

 glaciated shapes, and, on a few, obscure striations are present. 

 They range in size up to about six inches, and consist of quartz. 



