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backed up to a considerable extent before the dam broke. The water
came down with great force and built up a large tract of boulder delta.
It may have been through such accidents and during flood times that the
gravel and boulder deltas of the tributary streams were laid down.

At the horseshoe bend on Illiance river the stream has changed its
course. The bottom part of the old channel is filled with stratified gravel
and sand. Kitsault river from West creek south flows in a graded flood-
plain of recent gravel except for two short rock canyons apparently repre-
senting new courses taken by the stream.

Bear River valley from American creek to its mouth is floored with
eravels and sands deposited by the present stream. During times of high
water the stream commonly alters its course and sweeping against the
banks undercuts them and in this way widens the treeless part of the valley
bottom. The town of Stewart is situated on the seaward end of the delta.
The flat is being rapidly extended seaward by stream-carried sediment.
Data obtained by the Department of Public Works of Canada show that
on the west side of Portland canal the low water mark on the delta
advanced 540 feet between 1909 and 1927.

The streams entering Portland canal from the east are small and the
deltas at their mouths are also small. The largest are at the mouths of
Marmot and Georgia rivers.

At the head of Hastings arm the main stream valley is filled with
gravel and silt for a distance 4 miles from the sea. Hastings creek entering
Hastings arm and several creeks entering Granby bay at Anyox have
deltas.

FAULTS

Faults are numerous in the area. Definite breaks were seen in many
places and were topographically expressed, but it was difficult or impossible
to determine the direction and extent of the throw or the offset. Only
where faults cut across strata with individual characteristics could any-
ae definite be learned about the extent of the movement along the fault
plane.

No faults of great magnitude were seen in Alice Arm district but
faults of small offset are numerous. A fault of unknown offset strikes
northeast in lower Llliance River valley. A few faults striking northeast
cross Kitsault river near Evindsen creek. Most of the recognized faults
were seen in underground workings. The Dolly Varden vein has been
offset by a number of parallel faults striking in the main north-northwest.
These faults appear to be steeply dipping, reverse faults. The eastern
side of each fault has moved south with reference to the western side. The
greatest horizontal offset noted was 160 feet. Some faults in the Dolly
Varden mine with horizontal offsets of 50 feet have very little crushed
rock along the fault plane. The surface at the Dolly Varden mine is one
of moderate slope with many dry gullies 5 to 30 feet deep. Many of these
gullies have been formed along the crushed outcrops of faults. A northerly
striking fault crossing the LaRose mining property has a crushed zone
several feet wide and may represent a considerable displacement.

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