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Above the tuff-greywacke assemblage is a sequence of interbedded,
banded, sedimentary beds and grey-green andesitic flows. The flows or
groups of flows are in units 50 to 150 feet thick, and comprise about
one-third of this part of the section, which has a total thickness of 1,000
to 2,000 feet. Overlying the interbedded tuffs and flows is a thick series
almost entirely composed of andesite, with minor breccia and very minor
sedimentary rocks. The andesites are uniformly porphyritic, with pheno-
erysts of hornblende or pyroxene, or occasionally both. Scattered, light
grey feldspar phenocrysts occur in most of the flows, and are in a few
places the predominant mineral observed in hand specimens. Amygdaloidal
texture was observed in only a few places, and is confined chiefly to the
brecciated tops of flows. Flow banding or coarser layers are not conspicu-
ous in these rocks. The thickness of this uppermost exposed unit of the
Takla group in the Matetlo Creek area is estimated to be between 3,000
and 7,000 feet. The upper members of this unit are intruded by the
Hogem batholith.

The mountains between Tutizika and Mesilinka River Valleys expose
what may be a nearly complete section of the Takla group, but outcrops
are not continuous, and several fault or shear zones, together with inter-
ruptions and disturbances by numerous intrusive bodies, make it difficult
to obtain a satisfactory picture of the sequence or structure. The eastern-
most outcrops in this area, believed to represent the lowest part of the
Takla group section, are chiefly porphyritic andesite and breccia, partly
amygdaloidal, similar to the rocks found on Thane Creek and near the
Vega mineral claims. Some of the breccias contain conspicuous, relatively
dark-coloured, coarse-grained, amygdaloidal fragments. A few narrow
bands of slate and small lenses of blue-black, argillaceous limestone are
the only sedimentary rocks found in this area. The greater part of the
mountains north of Tutizzi Lake is composed of porphyritic andesite, with
comparatively little andesite breccia. Bedded tuffs are almost lacking in
the eastern and central parts of the main mountain massif between
Tutizzi Lake and Abraham Creek, but become more abundant toward the
west and northwest. Due west of the upper end of Tutizzi Lake, the
Takla group rocks in contact with the Hogem batholith are mainly bedded
tuffs and porphyritic andesite or andesite breccia with pyroxene pheno-
erysts. In Abraham Creek Valley and in the mountains immediately to
the south, tuff and greywacke and partly calcareous slaty argillite are
interbedded with the porphyritic andesite, comprising perhaps one-third
of the rock volume.

Mount Elsie, due south of Aiken Lake, exposes a typical mixture of
andesite, andesite breccia, and tuff, with minor interbedded argillite and
limestone. About 70 per cent of the rock volume is bright grey-green, dull
grey weathering, porphyritic andesite, with abundant black hornblende
phenocrysts up to 2 mm. long, and less numerous white feldspar pheno-
crysts up to 1 mm. in a fresh appearing, fine-grained to aphanitic, grey-
green matrix. The tuffs are for the most part confined to units of less
than 100 feet, but, together with argillite and greywacke, comprise a sedi-
mentary assemblage at least 1,500 feet thick near the middle of the
sequence exposed on the north face of Mount Elsie. The tuffs are well
sorted, and range from thick, dark grey and black beds composed of
fragments averaging about 2 mm. in diameter, to very fine-grained,