512 GREAT SERPENTINE BELT OF NEW SOUTH WALES, i., 



tiary, probably a Pre-Mesozoic age, for these dolerites. Possibly 

 they were intruded during the folding along an east and west axis, 

 which seems to have followed the meridional crumpling. It may 

 be that this movement was connected with that which lowered part 

 of the Carboniferous range, admitting the deposition of Permo- 

 Carboniferous sediments, in the lower series of which, are inter- 

 stratified, hypersthene, andesite flows, in the Newcastle district. 

 This relationship is, however, pure conjecture, there being little 

 or no evidence on which to base any reasoning. 



Following the main intrusions of basic igneous rocks, there 

 occurs a long series of granitic intrusions, ranging probably from 

 the latest Carboniferous to early Mesozoic times. The following 

 grouping of these, based on the work of Andrews(l8), Cotton(i6), 

 and others, must be regarded as tentative only. 



Upper CarboniferousC?) — l.Felsites of Bingara. 



Permian. — 2.Granodiorites and Porphyries of Nundle. 

 3.Sphene-Granites of Moonbi. 

 4.Tingha Granite. 



Early Mesozoic. — 5. The "Acid Granite." 



6. Tourmaline-granites east of Bingara and 

 Manilla. 



These masses of granite form a long series of intrusions lying 

 behind the serpentine-intrusion, i.e., in the direction from which 

 the thrust came. In three places, however, the granite-rocks occur 

 in front of the serpentine, namely, in the case of the Bingara fel- 

 sites, and also in the large area of sphene-granite that has cut 

 through the serpentine at Tamworth, and stretches between Moonbi 

 and Attunga. Again, in the Nundle district, the whole area is seen 

 to rest on a batholith of granite, which appears both east and west 

 of the serpentine-belt. 



The great and varied series of lamprophyre-dykes, which occur 

 occur along the serpentine-belt, cannot be referred to any definite 

 eruption-period as yet. Though they seem associated with the ser- 

 pentine, it is difficult to understand their genetic relationship; it 

 must be noted that the area between the serpentine and the granite, 

 in the background, has not yet been thoroughly searched, and it is 



