GEOLOGY. 
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river; but it was so much washed out and covered by the de¬ 
tritus from above, that I could not talce any measurements, 
although I observed that the same succession of strata occurred 
there; the strike was from south-west to north-east, with a dip 
towards the north-west of 31 degrees. Perhaps its position here 
is due to a merely local disturbance. The granite in the wedge 
is overlaid by a green arenaceous sandstone, the lowermost rock 
of the carboniferous strata. 
On the eastern side of the Papahaua chain, in Mount William, 
I again found the same strata striking regularly north-east and 
south-west, with a dip of 6 degrees towards the south-east. 
At the western foot of Mount Bochfort no granite is to be 
» found, but proceeding towards the north, we find it lying at the 
base of Mount Frederic. Here the strata overlying the granite 
dip towards the south-east. These carboniferous rocks cover an 
area of 120 square miles, and will one day be highly valuable, 
although at present the better position of the Glrey coal-field, 
the thickness of its seams, and the facilities it offers for working 
them, more strongly recommend it to the notice of the capitalist. 
A mile north of the Ngakuwaho stream the granite again makes 
its appearance, overlaid by young tertiary deposits. It is here 
syenitic, and more towards the north trappean, and changes in 
some places insensibly into felsite porphyry, as for instance near 
Kongahu Island. In other places the mica is replaced by chlorite, 
and large veins of the same mineral are visible, intersecting the 
rock. We meet also besides with many porphyritic granites con¬ 
taining large orthoklas crystals, and with others containing albite 
in greater proportion. Some of the trappean granites are full of 
rounded concretions of a blackish colour, and of a micaceous 
structure, exactly resembling the metamorphic schists which we 
observe near the hypogene rocks. These metamorphic rocks 
consist partly of micaceous schists and partly of granulites, and 
are intersected by occasional quartz veins. Their strike and dip 
are generally very irregular, although in some places, where I 
obtained good sections, their general strike was north and south, 
with a dip of sixty to eighty degrees towards the west. The creta¬ 
ceous rocks which we meet with at the junction of the Inangahua 
and Buller extend to the coast, which they reach to the north of 
the Mokihinui stream. Here they consist of a flaggy, bluish, and 
somewhat argillaceous limestone, intersected by large veins of 
calcspar, and in some places full of casts of fucoids.. This rock 
extends, with only occasional intervals, where granitoid rock crops 
out, to’the mouth of the Wanganui, sometimes assuming the 
character of a chalk-marl, and sometimes that of a tabular whitish 
crystalline limestone, full of large oysters, pectens terebratulas 
and pieces of corals, in connection with tne same fossils which 1 
observed in the rocks between the Buller and Grey; but here also, as 
in the latter rocks, I observed no signs of belemnites or ammonites. 
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