Page:Picturesque Dunedin.djvu/92

82, which runs out from the northern side. At low tide, when the inlet is principally mud-flat, the prospect is much less alluring. At Waitati Station we are again at sea-level, and to our left, up the valley, calcareous sandstones are seen, while further up the creek are oil shales and a seam of coal. From the native village of Puketeraki, we see the harbour of Waikouaiti, the northern headland of which is formed of the Ototara sandstone; this is sometimes pointed out as the natural harbour of eastern Otago, and had fate willed otherwise than it has, there is no doubt that the rolling downs behind the town would have made a charming site for a city. On our left is now the great mica-schist formation, with the coal-beds and greensands lying upon its flanks, and here and there a solitary basaltic peak, the remnant of a once continuous sheet, which, in Miocene or post-Miocene times, was poured over the whole district.

Just before entering the town of Palmerston, we pass through greensands, which are economically important, as they contain considerable quantities of valuable iron ore. A sample taken from the deep cutting opposite Mount Royal Station, though apparently consisting of little else than greensand, yielded, on analysis in the Colonial Laboratory, 37 per cent. of spathic iron ore. Large masses of this stone exist, and no doubt some day it will be utilised for the manufacture of iron.

From the foregoing sketch it will be seen that in this portion of Otago, the following formations are present:—
 * 1) Quaternary.—Recent Alluvium, æolian, and moa-beds.
 * 2) Cainozoic.—Caversham sandstone, volcanic series.
 * 3) Cretaceo-tertiary.—Coal-beds.
 * 4) Palæozoic.—Schists.

I. Recent.—The recent deposits in the neighbourhood of Dunedin comprise the river-beds, harbour deposits, and the extensive Æolian deposits on the coast. The last-mentioned are of considerable area and importance. They commence beyond Green Island, at Brighton, near the belt of schist, which here reaches to the sea, and forms the picturesque headland upon which the township is situated. Further to the east they increase in magnitude, and, as has been mentioned, the sand forms, at the mouth of the Kaikorai stream, a bar, which is swept away in times of floods, only to re-form as the volume of water becomes