66

(by difference), 54-2 per cent. It is a high-volatile bituminous coal. An
adjacent similar seam, not sampled, is about 4 feet thick.

A little coal was found 14 miles southeast at about the same strati-
graphic position, and other apparently smaller occurrences are shown on
the accompanying map.

Upper Cretaceous and Paleocene Deposits

Coal is present in both the Upper Cretaceous and Paleocene sandstones
of the Sustut group, but, with one known exception, occurs as minor, widely
scattered lenses, very few of which exceed a length of 5 feet or a thickness
of an inch.

The exceptional occurrence is 34 miles west-northwest of the mouth of
Asitka River, on the southwest slope of a ridge. The principal formations
are sandstones and pebbly sandstones of probable Upper Cretaceous age.
A few feet of coal-bearing strata overlie these conformably. The whole
assemblage strikes about south 70 degrees east and dips 55 degrees south-
west, about parallel with the surface on which the coal occurs. The coal-
bearing strata thus form a thin sheet resting on a dip slope, and an unknown
thickness of their upper members has been removed by erosion. The outcrop
is thickly strewn with fragments of black and light grey shale and coal,
and the thickness and number of coal seams is unknown. The coaly
fragments are made up of alternating bands of glistening black coal and
dull black shaly coal.

PROSPECTING NOTES

McConnell Creek map-area has provided ample evidence to warrant
an intensive search for ore deposits, but, as previously mentioned, very
little efficient prospecting was done prior to 1946. Theoretical factors
favouring the occurrence of sizeable mineral deposits include: (1) the
presence of granitic intrusions of at least two distinct ages (Omineca
and Kastberg intrusions), suggesting that metalliferous solutions may have
entered the formations at least twice during the geological history of the
area; (2) the complex structure impressed on a heterogeneous assemblage
of strata, a situation generally providing numerous channelways, such as
faults and shear zones, for rising solutions; and (3) the many square miles
of formations that border and overlie the Omineca batholith and thus
lie more or less directly in the path of such mineral-bearing solutions
as may have risen from the underlying magma. The known mineral
occurrences, some of which have been described above, provide concrete
evidence that solutions containing valuable metals reached this favourable
terrain; but only a careful, intelligent, and persistent search can prove or
disprove the presence of orebodies.

Most of the known metalliferous deposits are in voleanic members of
the Takla group (units 3A and 4 on the accompanying map) and, accord-
ingly, areas underlain by these rocks afford promising prospecting ground.
Most gold-bearing veins reported to the end of the 1947 prospecting season
occur in Takla voleanic rocks of the lower division lying east of a line
extending northerly from the source of Mesalinka River, through Dortatelle
Peak to McConnell Lakes. These deposits are presumably of Mesozoic
age, genetically related to the Omineca intrusions. Perhaps the most promis-