Page:Transactions NZ Institute Volume 9.djvu/613

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Smith.Geology of Northern Portion of Hawke Bay.
567

the innumerable long narrow arms, charming little bays, and rocky islets of the southern and western shores, are equally beautiful in their way. The Aniwhaniwha Waterfall, at the north-east end of the Lake, is well worthy of a visit; a boat can be taken right up to the deep pool at its foot, and from there the double Fall can be seen to great advantage as it tumbles over the sandstone cliffs. The shores of the Lake are everywhere very steep, and, with a few exceptions, covered by forest right to the water's edge, the most common tree being the beautiful Beech.

The surplus waters are carried off by the Waikaritaheke River, though in ordinary weather the outlet is not visible, being subterraneous. On descending the dry watercourse of the river some little way, however, it is seen bursting forth from a crevice in the rock, and thence descends in a series of rapids to join the Wairoa, falling in the first three miles as much as 1,500 feet. There are several of these underground outlets, which are sufficient under ordinary circumstances; but after very heavy rains, or a westerly gale, the lake rises sufficiently to overflow the rocky bar at the mouth of the river, and then the water descends as a flood. The height of the lake above the sea is 2,015 feet, and that of Waikare-iti, a small lake situated a few miles to the north, is 3,122 feet, being probably the highest sheet of water in the island.

Lower Papa.

Resting on these Waikaremoana sandstones, the next formation, is a a great thickness of calcareous clayey marls, known universally on the East Coast by the name of "Papa Rock." This papa rock occupies probably the largest surface area of any rock met with between the East Cape and Napier. It is not, however, a continuous formation. I believe it to be of several different ages. At the line of junction between this and the underlying sandstone there is evidence of a break in the continuity of deposit, as may be seen in the valleys of the Waikaretaheke and Ruakituri, where the Papa contains embedded in it large boulders of the sandstones, showing that an elevation of the sandstone must have taken place sufficient to have formed a coast line upon which the denuding powers of the sea had been exercised in the formation of these boulders. The dip of the two formations is, however, very nearly the same. These beds are generally distinctly stratified, with here and there bands of a much harder and more sandy rock. At the point where the Waiau River first enters them, are to be seen embedded in the Papa large boulders of exceedingly hard yellowish cement stones or septaria. They are best seen under the Pukaramea Bluff, where the beds of the streams are often filled with them. Fossils are apparently scarce, though no doubt a proper search would reveal a great many more than I saw.