GEOLOGY. 
113 
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exhibit in some respect a different aspect, the soft sandy clays not 
occurring, and being replaced by large accumulations of con¬ 
glomerates. A very striking feature is that these beds lie almost 
horizontally, forming near the sides of the granite wedge, vertical, 
and even in some places overhanging walls, from 500 to 1,500 
feet in height. 
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These strata do not appear to have been upheaved by granite 
when in a soft state, but when this rock was in a solid condition, 
a proof ot which we find near the sea, north of the Hgakuwaho 
stream. There large masses of porphyritic granite occur, re¬ 
sembling that which has protruded through the older svenitic 
granite. IN ear it we meet with a granitic breccia, consisting of 
large angular pieces of syenitic granite and micaceous rocks, 
embedded in a trappean granitic matrix, which could not have 
been formed by the rolling of the waves on the shore or by sub¬ 
marine currents, but only by friction, when the intruding masses 
upheaved the syenitic granite, and with it the coal-bearing strata, 
so that the pieces which were detached by this vertical movement 
became embedded in the granitic matrix. In some other places, 
as, for example, to the north of Mount Frederic, the porphyritic 
granite has itself intruded into the coal-bearing strata, and many 
highly interesting rocks have been formed by alteration of the 
grits, coals, and shales. 
From the top of Mount Eochfort to the course of the Wai- 
mangaroha, which separates the last-named mountain from Mount 
Frederic, the general strike of the carboniferous rocks, which 
attain here a thickness of 3,500 feet, is from east to west, with a 
dip from 4 degrees to 7 degrees north. Having examined these 
strata somewhat closely, I am enabled to give the following table 
of succession, in descending order, beginning at the top of Mount 
Eochfort. 
FEET 
Coarse grits, with small beds of fine grained sandstones .... 80 
Conglomerate, in a matrix of white quartzose sand, consisting of rounded 
pebbles of quartz and quartzite ....... 30 
Ferruginous sandstone (grindstone) ....... 6 
Conglomerate ........... 40 
Sandstone, arenaceous, whitish green.8 
Conglomerate, alternating with smaller beds of sandstone . . . 200 
Very micaceous grits .......... 120 
Shales ............. 1^ 
For the next 500 feet, the same alternating succession of grits 
and shales continues, as observed in the gullies round Mount 
Eochfort, but without any apparent indications of coal. The 
shales, where not too micaceous, are replete with impressions of 
plants' all specifically the same as those in the Grey coal-field, 
of which a Voltzia is here the most conspicuous. Below them 
again, for several hundred feet, slaty sandstones occur, succeeded 
bv the orits and shales, amongst which I discovered a coal-seam. 
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