'I'lIE UEOl-OUl' Of KlIJLSOJf. 
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87 
(b .) Zone of Hornblende Schist and' Glirystalline Limestone 
( UrJmlJc) .—Proceeding from the granite and gneiss towards 
the west, we next meet, on the top of the Pikikerunga range, 
between Biwaka and Takaka, a broad zone, on which horn- 
blende-schists, quartz-schists, and crystalline limestone succeed 
one another in regular and numerous alternating strata, with 
a vertical dip and a strike nearly due north and south. This 
formation continues in a westerly direction to the opposite side 
of the Takaka valley, where it is broken through by eruptive 
masses of diorite-porphyry and serpentine, which show them¬ 
selves in the Stony Creek and Waingaroa. The same zone of 
crystalline schists exhibits itself in the steep escarpments ol 
the gorge of the Wangapeka. A characteristic feature of this 
limestone formation is the existence of numerous funnel- 
shaped pits, which have been hollowed out by the action of 
water, which has dissolved the limestone. 
The interesting phenomenon of the Waikaromumu springs 
in the Takaka valley, where whole rivers suddenly appear on 
the surface with the water bubbling, is readily explained by a 
subterranean passage of the water through the limestone from 
the ranges. This crystalline limestone on the ranges must not 
be confounded with the other limestone in the Takaka \ alley, 
which belongs to the tertiary period. 
(c\) Mica Schist and Quartz-Schist— The crest of the western 
ranges, with peaks rising to an altitude ot about 6,000 feet, the 
Anatoki mountains, Mount Arthur, and the chain lying 
between the source of the \Vhngapcka Brver and the Lullci 
river gorge, consists of mica schists, containing garnets, alter¬ 
nating with quartz schists. 
( ( d .) Zone of Clay Slate. — Still proceeding towards the west, 
the mica-schists pass, by insensible gradations, into clay slates, 
which, however, still exhibit the same alternating strata of 
quartz-schist. The Aorere valley and the lofty peaks on its 
eastern side, as the SlatefR-iver peak, Lead Hill, Mount Olym¬ 
pus, and the Haupiri range, generally belong to the clay-slate 
zone. In all these ranges the strata are more or less vertical, 
and exhibit unmistakable signs of great disturbance at former 
geological periods. Bor instance, Mount Olympic presents 
the peculiar appearance of strata diverging from below towards 
the serrated edge of the mountain, like the folds ol a lain A 
G- 
