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shore of Kitsumgallum lake, there are both altered diorite dykes and
lamprophyre dykes cutting granodiorite. The altered diorite dykes were
intruded prior to vein formation, but the lamprophyre dykes are later
and one may be seen cutting the quartz vein in an adit on the lake shore.
A small diabase dyke cuts the diorite on the Lucy O’Neil claim and
forms the hanging-wall of the vein.

The quartz-albite dykes in the southeastern part of the area are of
particular economic interest as many of them have quartz veins along
both walls, as on the Dardanelle and St. Paul properties. Alaskite dykes
were noted by Hanson in 1925 with this relation to quartz veins on Legate
and Chimdemash creeks. Both the quartz-albite and alaskite dykes are
identical rocks, but the latter are coarsely crystalline.

SKEENA FORMATION

Skeena formation of Lower Cretaceous age may occur in the drift-
covered valley north of Kitsumgallum lake. Occurrences of coal-like seams
of carbonaceous shale north of Cedar River bridge suggest the presence
of these rocks. In typical localities, as in the vicinity of Telkwa, the
formation consists of basal conglomerates, sandstones, and argillites, with
occasional coal seams. The sediments are believed to be remnants of an
extensive formation laid down unconformably on the Hazelton series and
subsequently largely removed by Cretaceous and Tertiary erosion.

Graphitic carbonaceous seams also occur in the Hazelton sediments.
One of these a foot wide may be seen in places along the foot-wall of the
quartz vein on the Gold Cap claim, Maroon mountain. As the two forma-
tions are much alike lithologically, the presence or extent of the Skeena
formation in the Kitsumgallum-Cedar River valley will not be known
until more detailed mapping is done.

PLEISTOCENE AND RECENT

Scattered glacial boulders are found over the whole area and glacial
strie are present in many places parallel to the main valleys. Boulder
clay is not common, but is usually found in small amdéunts in the tributary
valleys of the larger rivers and lakes. Small, morainal deposits have
accumulated at the foot of the alpine glaciers.

Extensive gravel deposits cover the floor of Kitsumgallum-Lakelse
valley and gravel terraces occur up to 200 feet above all the large streams
and lakes. These deposits are believed to have been formed during the
wane of the Glacial period and in Recent time through extensive deposi-
tion by overloaded streams and by deepening of the river channels. A
number of clay horizons occur in the gravel beds at Terrace and furnish
important water horizons. A vertical drill hole bored at Terrace is reported
to have passed through 450 feet of gravel. Flood-plain deposits of sand
and silt furnish a fertile soil in Terrace area.

ECONOMIC GEOLOGY

The initial discovery of gold and copper in the vicinity of Usk in
1894 precipitated a mild staking rush in that vicinity, but it was not for