Thickess.
Feet inches

Red clay shale

Coaly shale, in part replaced by a thin sill
Light grey shale

Soft sandstone with thin coaly bands
Grey shale

Coaly shale
Green shaly sandstone
Coal, variable character

i tt.oe/ In, to’ 7 ft:
Floor is of sandy shale.

Structure. The Yakoun basin is an irregular, elongate
syncline, extending from the Tlell river in township 6, about 63
miles north to near the east-west centre line of township 8.
Except locally, it does not exceed 2 miles in width.

The syncline is complicated by a number of minor folds
which make prospecting uncertain and which are difficult to
work out on account of the variable character of the rocks,
and the lack of horizon markers.

The rocks in the vicinity of Camp Wilson are poorly ex-
posed, and Wilson creek and the prospect openings afford the
only data from which to determine the structure. The seam is
on the western limb of a narrow syncline, apparently canoe-
shaped and pitching slightly to the north. This western limb
is complicated by a small anticlinal wrinkle at Camp Wilson,
accompanied by faulting, and this increases the difficulty of
prospecting. The structure can not be completely diagnosed
from the outcrops and openings at present available, but Figure

11