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each deformation of the rocks of Graham island. The earliest
recognized fault is the one which forms the western boundary of
the Queen Charlotte series at South point in Skidegate inlet.
This fault is clearly in evidence on the east side of the point, where
Honna conglomerate is in close juxtaposition to the Maude form-
ation, proving an easterly downthrow. It is not clear whether
the fault is normal or reverse, but it is probably normal. The
direction is somewhat conjectural, but the fault may well be the
same one that affects the coal seam at the old Cowgitz mine,
and it has been so mapped. Cutting this fault and displacing it,
and, therefore, later than it, is an east-west break, the effects of
which are plainly visible from Steep point to Lina narrows.
This is probably a normal fault with a northerly downthrow,
and in its westward continuation may pass through the marked
east-west valley between the mouth of Long arm and North
arm.

In the vicinity of the mouth of Slatechuck creek there are
areas of the Maude formation which bear relations to the later
sediments that can be most readily explained by the faults
shown on the map. By this assumption of a fault block of the
Maude in the lower Slatechuck valley the absence of the Honna
conglomerate in this vicinity is explained.

A fault with a general east-west direction crosses the south-
east end of South island. It has a northerly downthrow, bring-
ing Haida shales sharply against the Maude formation, and,
therefore, may be of considerable displacement.

The attitudes of the formation on Nose point and on the
adjacent ends of Maude and Lina islands are best explained by
supposing a normal fault to occur in the Channel between these
islands and Nose point. This fault has apparently a direction
a few degrees west of north, and a westerly downthrow of about
500 feet.

Faulting in the interior of the island is almost impossible
of detection on the surface on account of the rarity of exposures.
On a minute scale the flaggy argillites of the Maude formation
are known to be extensively fractured, and minor faults have
been detected in prospect openings at various places in the
Haida formation of the Queen Charlotte series.