Bocks of Noyang. 55 



neighbourhood of this intrusive mass the strike of the sedi- 

 ments has been diverted to nearly east and west. This is 

 not an isolated case, for I have observed the same deflection 

 of the normal strike adjoining intrusive areas at Swift's 

 Creek, Dargo Flat, and other places in Gippsland. This 

 shows the enormous disturbance of the earth's crust which 

 accompanied the extra vassation of the once molten masses. 



This deflection of the strata east and west is observable 

 at Shady Creek, about three miles from the contact. The 

 dip to either hand is so slight that, practically, the beds 

 may be looked upon here as vertical. The alteration observ- 

 able in these alternating sandstones and slates is an indura- 

 tion generally, and a slightly spotted appearance of some 

 of the more fine-grained beds. Narrow veins of quartz, 

 with traces of chlorite, are very frequent. From this point, 

 in gfoin^.south wards, the sediments soon resume their normal 

 appearance, and no igneous rocks reappear, the Silurian strata 

 disappearing at a distance of about ten miles underneath 

 the marine tertiaries. To the north the sediments become 

 more and more altered into contact schists as they approach 

 the Noyang area. 



I prepared several slices from samples collected at Shady 

 Creek, and also from the northern side of the range of hills 

 across which the old line of road leads to Noyang. 



Shady Creek. — I found a sample of one of the fine-grained 

 beds to have the following composition : — The slice was 

 prepared parallel to the bedding. It is mainly composed of 

 overlapping more or less rounded plates of a colourless or 

 faintly green mineral. In places where these plates are seen 

 edgeways, they are twisted, bent, ragged edged, and very 

 slightly dichroic, and where numerous form what may not 

 inaptly be called a " foliation." When the rock is examined 

 between crossed nicols, these plates behave like sections of a 

 uniaxial mineral, and this comes out much more clearly 

 when a Klein's quartz-plate is used. The characters of this 

 mineral suggest strongly that it is chlorite. In this mass 

 are numerous small grains of quartz, and a considerable 

 amount of black granular material, which is probably 

 carbonaceous. 



A second slice I prepared from one of the coarse-grained 

 sandstones of Shady Creek. The ground-mass of the rock 

 is composed of materials precisely similar to those of the 

 last described sample, that is, mainly of a chloritic mineral 

 and minute grains of quartz ; but there are, in addition, a 



