Account of Gldcial Deposits of Biwchiis Marsh. 51 



these may liave weathered away. In many parts of the 

 Scottish Highlands, where the whole country shows the 

 rounded and flowing contour chai-acteristic of ice-action, it 

 is often very difficult to find actual scorings and grooves. 



Some little distance further up the Creek a section has 

 been exposed by the stream, showing some feet of a hard 

 unstratitied material containing striated stones. This was 

 much hardei- than any we had previousl}', examined, and was 

 traversed by joints. It was seen to be clearly overlaid by 

 sandstones, the junction between the two being very 

 distinct, there being apparently an unconformit3^ Here a 

 fault occurs through tl^e sandstones and the underlying 

 material, the displacement being about seven feet, and the 

 hade at a high angle. There would seem to be no doubt 

 that the overlying sandstones are continuous Avith the 

 surrounding ones, which, as we have seen, are probably 

 Triassic. So now it seemed probable that we had to deal 

 with two glacial deposits. 



At the junction of the Myrniongand Werribee, the latter 

 stream is seen to be flowing over the highly inclined and 

 sorely denuded edges ot Lower Silurian rocks, here consisting 

 of very hard, flne-grained, well stratified sandstones. On 

 the weathered surface the colour of these is of a patchy 

 yellow rusty colour, but on the fractured fresh smface they 

 are of a light greenish white, or light slaty white colour. 

 On proceeding up the Werribee from the junction, we found 

 ourselves walking over another kind of inaterial, which was 

 seen to rest unconformably on the Silurian rocks, which it 

 closely resembles in colour. The Creek has cut its way 

 through this to the Silurian, so that on the floor of the river 

 course one walks now on a few feet of Silurian, and now on 

 this other deposit, while sections are exposed on both sides 

 of the stream. This deposit consists of an exceedingly hard 

 clayey material, through "which are scattered stones and 

 boulders of considerable size, of granite, quartzite, flne- 

 grained hard sandstones (very similar to the underl3dng 

 Silurian), and quartz. Nearly all these present the flattened 

 sides, and striated and grooved surfaces characteristic of ice 

 action. The stones and boulders at this point are very 

 numerous, and the scorings and scratchings exceptionally 

 well developed. This conglomeiate resembles those already 

 described, in the absence of any appearance of stratification, 

 the character of the included stones, and the total want of 

 arrangement of the latter. In fact, it cannot be distin- 



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