1919.] 
Departmental Reports. 
399 
Sj tramway three or four miles in length would be required to bring coal 
to the river-bank at a point thirteen miles from the mouth of the Mokau. 
Any vessel able to enter the Mokau River could reach this point without 
difficulty. 
The Tangarakau section of the coalfield has been very imperfectly 
explored. Coal outcrops on the proposed route of the railway between 
Whangamomona and Ohura. The rail-head is now at Tahora, about three 
miles in direct line from the nearest coal, but the surveyed route of the 
railway between these points is five miles in length. In view of the above 
the writer is of opinion that a reconnaissance survey of the Tangarakau 
section of the coalfield should be undertaken. 
Coal Prospects at Waiwera, Auckland. 
By J. A. Bartrum, Lecturer on Geology, University College, Auckland. 
In accordance with instructions I visited Waiwera in November, 1917, 
and examined the coal prospects on Major J. Whitney’s property. The 
property includes the coast-line between Waiwera and Puhoi Streams, and 
extends inland approximately to the Waiwera-Puhoi Road. 
The geology of the surrounding area is well described by McKay (Rep. 
Geol. Explor. 1883-84, p. 104, 1884), and a few words will add what local 
detail is necessary. 
The so-called coal-seam is a thin, somewhat irregular band, up to 
1J in. thick, of bright coaly matter, traceable for over 50 yards at low 
water at the North Waiwera head. It is bedded in grey and green, some¬ 
times tufaceous, sandstones of the Waitemata series, about 100 ft. below 
a well-marked conglomerate bed composed very largely of volcanic material 
(hornblende and pyroxene andesites), about 20 ft. thick, and crowded with 
polyzoans, a few corals, a few Foraminifera and sporadic molluscs. Some 
of the finer sandstones just above the coal-seam also contain a few 
molluscs, the only form I recognized, however, being Nacula sp. Broken 
plant-remains are common. 
The volcanic conglomerate in places is coarse, but the fragments are 
in general about the size of a pea. In contrast with the well-rounded 
pebbles of sedimentary rocks included the fragments of volcanic origin are 
mostly harsh and poorly rounded. This conglomerate obviously marks the 
Parnell grit ” horizon. 
The beds are locally considerably disturbed, mainly by fault move¬ 
ments. In undisturbed portions, such as that including the “ coal-seam,” 
the dip is gentle (10° to 12°), and near the Waiwera bridge the beds are 
almost horizontal. 
Thin coaly bands of similar nature to that discovered by Major Whitney, 
but not quite so continuous, can be seen at one or two other points along 
the foreshore towards the Puhoi entrance, and are a well-known feature 
of the “ Waitemata ” beds in the vicinity of Auckland. In no case have 
they been found to thicken out into seams of any commercial interest, 
and the present band cannot be regarded as offering any greater promise 
than similar ones in the “ Waitemata ” beds of other localities. 
The probability of finding workable coal is so slight that the expense 
of boring in search of it would not be justified even were the strata not 
disturbed by faulting. 
