Speicut.—Benmore Coal Area of the Malvern Hills. 623 
On the western side of this gully three basic dykes occur. The most 
easterly of these is exposed in a face consisting of hard and soft sandstones. 
It is about 5 ft. wide, and strikes N. 5° E. A narrow band of altered 
material lies alongside the dyke. This appears to be the one referred to 
H cit., p. 45). Two other dykes also occur on the crest of the 
ridge dividing the basin of this creek from the next one lying to the west. 
These dykes may be part of one main intrusion, = as they appear on 
the surface they are quite distinct, and sands are exposed on the — 
š ce, which r 
N. 15° E., but the other is not defined where exposed, although the поа 
to the westward are covered with detached blocks over a considerable area. 
They have both been intruded into sands. 
The rock of which these dykes are formed is a very basic basalt. In 
undmass composed of feldspar laths, augite granules, and rather long 
individuals of magnetite with the skeletal outline of ilmenite, there are 
many phenocrysts of olivine and augite, the former predominating i in number. 
ome of these show signs of serpentinization, but they are usually fresh 
and colourless, or with cracks stained with oxide of iron. They, as well 
as the augite, frequently form aggregations. The rock does not show any 
close relation to the teschenitic varieties which occur at High Peak and 
at Rakaia Gorge, but is more closely connected with the basic rocks of the 
oe areas of the Malvern Hills. 
The next creek to the west is the main source of Macfarlane Stream 
(see Section 2). On the north-west boundary of the outlier a and 
€ with coal lie on the greywacke, but the country is much slipped. 
e beds are succeeded by sands and greensands, well exposed in a gully 
co iig in from the north, and also in a tributary coming in from Benmore 
on the south. The line of the former has been determined by a basaltic 
intrusion. On its south-east side shales at times carbonaceous, sandy 
shales with gypsum crystals and greensands, and sands with concretionary 
bands are exposed, striking north-east and dipping south-east at angles 
of from 35° to 40°. In the tributary from Benmore there are sands of 
varying оіан) —grey, brown with тағу гоп, green with glauconite, 
and yellowish-white passing into white—all dippitig south-east at an angle 
of 30°, the whole thickness of the coal-measures in this part of the area 
on the surface on the north-west boundary of the area. It can be traced 
from a saddle in the extreme south-west corner of the basin. Although 
Haast looked on this occurrence of igneous rock as a surface flow, there is 
little doubt that it is an intrusion in the form of a sill The following 
points are of importance in this connection: (1.) The contacts of both the 
upper and lower surfaces are intrusive contacts, the beds both above and 
below the mass being affected by its heat. (2.) It is not parallel to the 
stratification, but crosses it at a small ang 
Haast evidently thought that all Вах igneous occurrences belonged 
to one great sheet, but the evidence clearly points to their discontinuity 
on the surface 
Where the tributary creek from Benmore crosses the boundary of the 
coal-measures there is decided evidence of faulting on a large scale. 
No actual contacts can be seen, owing to debris slopes coming from the 
