23 
C.— 13. 
creeks, where, as it progresses along the different tail-channels, it is gradually liberated from contact 
with the ironsands, and, as free gold, is caught on tables called “ fly-catchers, placed in the channel 
to intercept the gold. _ . 
There are large areas of black-sand and gravel deposits in the Charleston district that are as 
yet untouched, but all of them lie to the west of the limestone range. 
East of the limestone range, between that and the foot of the Paparoa Mountains, lies a depres- 
sion lower than the country to the west, yet over this there are no black-sand deposns. Tl.i:, fact 
may be explained by supposing that the marine sands have been removed by the more energetic 
denudation of the eastern low-lying lands, or by the inequality' of elevation affecting the areas east 
and w T est of the limestone. The first of these suggestions, from the evidence met with noith of the 
Totara Biver, would seem to be the correct one, since on the high terrace at the back (east) of 
Addison’s Flat the black-sand deposits are yet preserved. To the north of the Buller the higher 
level of the terraces between the granite range and the coastal plain is also to be considered a con- 
tinuation of the high-level black-sand lead. This series of old raised beach deposits in the beginning 
has been spoken of as the Houhou Lead ; but it will now be evident that such local designation fails 
entirely to indicate the true character and the great importance of the deposit ; and in future it will 
be best to speak of this as “ Marine beds of Pliocene age,’ the different auriferous parts of which 
might still retain their local designation, as “ Houhou Lead, “ Lamplough Lead, “ Darkies 
Terrace,” &c. ... 
So far as this report is concerned, the deposits under consideration may be said to terminate at 
Fairdown, on the lower slopes of Mount Bochfort, where extensive works are at present being 
carried on for the proper development of their deposits, the success of which will probably lead to 
future and even more extensive undertakings. 
IV. Lower Pliocene and Upper Miocene. 
Formerly the higher and lower parts of these beds were considered as distinct from each other ; 
but it must be confessed that it is not always easy to distinguish between the graveL referred to 
under one or other heads. In some localities there appears evidence that the conditions under 
which the higher beds were deposited approached those of a glacier period, there being in some 
localities large erratic boulders, and sometimes heavy deposits of what appears as angular morainic 
material of largo size ; and at plaees such evidences of glacier action appear at the top of a local 
development of the beds, at others in the lowest member of such local development. The lower 
part of this great series of gravels does not exhibit brecciated or angular material of great size. 
Angular material of any size is present to a very limited extent only. With these differences it has 
to be considered how far the upper and lower parts of these gravels are unconformable to each 
other. The evidence of unconformity is strongest in the district between the Big Grey and the 
Ahaura, and especially in the neighbourdfood of Napoleon Hill. In Napoleon Hill the unconformity 
is by many miners declared to be very marked, and the upper gravels are said to lie in what 
resembles an old river-bed, excavated in the underlying “Old-man bottom. Some facts thus 
favouring the division of the beds, and it being the opinion of many that there is a distinct and very 
marked separation between the higher and lower parts, they will be here described accordingly 
that is, as a double series. 
(a.) Humphrey' s Gully Bads.— In the highenpart of Mont d’Or, at Boss, there is, at the head 
of Sailor’s Gully, clear evidence of glacier drift occurring in the higher part of the “ Old-man bottom, 
as developed at that place ; the same thing is seen on the north-west and south-west faces of the hill, 
which has been cut into on three sides by gold-workings. These glacier drifts are thought not to 
be gold-bearing, hut this has yet to he definitely ascertained. 
In Humphrey’s Gully Range, near the Humphrey’s sluicing claim, angular brecciated material 
lies at the bottom of the gravel series, and to some extent is interbedded with the underlying sandy 
clays. The same glacier-looking deposit is largely developed beyond German Gully in the steep 
bluff that there overlooks the Arahura Biver. At this point the whole bluff is composed of a species 
of “ till ” or less clayey brecciated material. There may also in Humphrey s Gully Bango be the 
presence of the lower beds of this series ; but, as the upper series is very^ thick, and the lower not 
discriminated, it has been considered that only the. upper or Humphrey s Gully beds are present. 
In Donegal Creek, six miles from Kumara, on the road to Christchurch, there is a considerable 
thickness of coarse well-washed gravels that have been referred to this upper part of the series, and 
the same gravels again appear one mile and a half nearer Kumara, there showing in the road cut- 
tings. North of the Teremakau this higher part of the series has not, apart from the lower beds, 
been discriminated. 
Within the northern part of Westland these beds, at Boss, are important as gold-bearing 
gravels both in Mont d’Or and in the Boss United Claim, because it can hardly be doubted that 
some of the many gold-bearing strata in the latter claim represent this upper series of Older Pliocene 
or Upper Miocene gravels, seeing that gold-bearing layers rest directly on the “ Old-mau bottom 
in the company’s ground, and probably throughout the greater extent of Boss Flat. In the 
Humphrey’s Gully Company’s claim, and probably throughout the extent of the same gravels in the 
Humphrey’s Gully Bange, these gravels are gold-bearing, and, on account of the facilities forgetting 
awav large quantities of the wash, are likely to reward enterprise for a long series of years to come. 
In the Grev Yallev the higher beds of these, the higher beds of the series, are developed on 
the tops of the hills, on the northern side of Nelson Creek opposite Hatter’s Terrace, and thence it 
is likely that a line of the same gravels will be found to have extended, with a breadth of from one 
to one and a half miles, across the various creeks and larger streams flowing north-west to the 
Grey, for the whole length of this particular block of hilly country formed of Older Pliocene or Upper 
Miocene gravels. The younger and richly auriferous part of the series is found on the ridge of hills 
on the left or south-west side of Orwell Creek, and, crossing this, occurs to the north-east, forming the 
