394 The N.Z. Journal of Science and Technology. [Dec. 
that the near-by volcanoes were not yet extinct. The rocks of this, series 
cover a small area in the south-western corner of the subdivision, but 
they extend far to the southward and form the argillaceous sandstones of 
Whitecliffs, Mount Messenger, and the Mimi Valley. 
Near the sea the older Pleistocene deposits consist of beach and 
estuarine beds of small extent. Inland fine subaerial pumiceous deposits 
cover large areas up to a thickness of 12 ft., and a large proportion of the 
soil covering in the north-eastern portion of the subdivision is derived from 
this rhyolitic material. Of younger Pleistocene age are the beach and dune 
deposits on the prominent marine terrace of the coast. These contain a 
notable amount of iron-ore, and from them have been derived the black- 
sand beaches and dunes of Recent age that fringe the shore. 
As already pointed out, two series of coal-bearing rocks outcrop within 
the subdivision. The older, underlying the Te Kuiti limestone, contains 
coal-seams at a few points only, and these are thin and probably of small 
areal extent. The coal in the younger series of beds is much more valuable, 
and was worked to a small extent for many years. Access to the mine 
was by the Mokau River, the channel of which was blocked by timber 
and debris during a flood a few years ago. Other materials of economic 
interest occurring in the subdivision are the limestones of the Mokau and 
Mohakatino Rivers and the ironsand of the coast. 
The Taranaki Coalfield. 
By J. Henderson, New Zealand Geological Survey. 
What may conveniently be termed the Taranaki Coalfield covers a consider¬ 
able area in northern Taranaki and the adjacent south-western corner of 
the Auckland Land District. The principal rivers draining this area are 
the Mokau, flowing to the Tasman Sea, and the Ohura and Tangarakau, 
large branches of the Wanganui. In this preliminary report the coal- 
outcrops will be described as they occur within or close to the basins of these 
streams. 
Mokau River Section. 
Mangaoruha .—The Mangaoruha, a small branch entering the Awakino 
from the south-east about thirteen miles from the sea, cuts deeply into the 
western edge of the coal-measures. The rocks here dip gently to the south¬ 
eastward, and do not contain much coal. An outcrop 60 chains from the 
mouth of the Mangaoruha was the only one observed. The seam, which is 
contained between beds of massive sandstone, is about 3J ft. thick. 
Mangaawakino .—The Mangaawakino is a fair-sized stream joining the 
Mokau from the north about thirteen miles from its mouth. About two 
miles and a half from the Mokau it is joined by the Kaipaku,. in which 
stream, one mile and a half from the junction, a seam 6 ft. to 8 ft. thick 
is well exposed. The strike is nearly east and west, and the dip southward 
at an angle of 3° or 4°. The floor is massive sandstone, and the roof carbon¬ 
aceous shale a few inches thick, succeeded by massive sandstone. Two 
seams, each about 1 ft. thick and separated by 10 in. of shale, occur in this 
locality at an horizon 40 ft. higher. 
In the Mangaawakino two seams each 3 ft. thick, and separated by 
15 ft. of shale and sandstone, are exposed 50 chains above the Kaipaku 
junction. Another seam lower in the sequence, and at least 3 ft. thick, 
outcrops about 20 chains farther on, and appears at intervals in or near the 
stream-bed for about a quarter of a mile. A still lower seam, showing 6 ft. 
of coal, is exposed at a point rather less than two miles from the Kaipaku 
