A body of granodiorite occupies 16 square miles north
of Stuart Lake. It isa medium=crained white rock composed of
white feldspar, quartz, and biotite, Jointing in three directions,
two vertical and one horizontal, is well developed, This grano-
diorite body has not been completely umroofed, so that roof

pendants and inclusions of metamorphosed Carboniferous rocks are
common in the area,

A body of granite, 25 square miles in area, cuts the
Carboniferous rocks in the Middle River Range. It is a medium-
grained grey to whito rock composed of albite, quartz, anda
little biotite. Contact phases of syenite are found. As in many
of the other granitic rocks in the area jointing is well developed
in three directions, two being vertical as elsewhere, but the
third direction instead of being horizontal is at an angle of
45 degrees to the horizontal,

Stocks of albite syenite and augite diorite outcrop
south of Redrock Lake, and west of Stuart Lake, respectively.

The acid intrusives intrude the Carboniferous rocks and
Mesozoic (?) basic intrusives, and are overlain by volcanics
believed to be pre-Upper Eocone,

Dyke Rocks

Dyke rocks believed to be related to the Mesozoic (?)
acid intrusives cut the Carboniferous strata, and in places cut
the acid intrusives., Along the shores of Trembleur Lake numerous
grey to buff, fine- to medium-srained, porphyritic and non-
porphyritic, granitic dykes, varying in width from 6 inches to
100 feet, can be seen cutting the Carboniferous strata, They are
composed of quartz, feldspar, and minor accessory minorals,
pyrite in many cases being conspicuous.

Grey-green to dark green, aphanitic to fine-grained,
porphyritic and non-porphyritic lamprophyre dykes, up to 10 fect
wide, cut the diorite body north of Babine Lal and the sranite
body in the Middle River Range. Associated with these lampr o-

phyres are aplite dykes, varying in width from an inch or two to
one foot.