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It is to be expected that in saturated rocks, petroleum, a
liquid lighter than water, will rise to the highest part of its con-
tainer, the oil sand. For this reason, oil is frequently found at or
near the crests of anticlines in saturated rocks; but it is also
found along flat areas in the sand, or where changes of dip from
flat to steep occur. Other apparently anomalous occurrences
may be explained as due to varying porosity of the sand or
caused by varying conditions of saturation by water and ground-
water movement.

It is to be emphasized that without the conjunction of these
four conditions in an individual area, no search for oil can hope
to meet with success.

CONDITIONS ON GRAHAM ISLAND.

It now remains to critically examine the occurrences of
bituminous matter in the various formations and districts of
Graham island, in the light of the facts given above, in order to
arrive at a conclusion in each case as to the probability of work-
able deposits of petroleum being found by drilling. As in the
descriptive portion of this report, the formations will be taken up
in the order of their age, beginning with the oldest.

In the Maude formation conditions 1, 2, and 4 are not ful-
filled. No liquid oil has ever been observed or reported from
this formation, and the tar which does occur is so viscous that
it flows only when heated by the sun. None of the beds of the
formation, except some of the tuffs at the top, are at all porous.
Elsewhere in it are found only dense partly metamorphosed
argillites and fine tufaceous sandstones. Finally, the rocks,
though the structure perhaps may be locally favourable, are on
the whole so extremely broken up and traversed by joints and
faults that it is extremely doubtful that any large body of petro-
leum could be confined in them. The types of structures found
in this formation are illustrated by Figures 2 and 5.

In the Haida formation, where the last three conditions as
given above may in some places be fulfilled, there is almost no
sign of petroleum of any sort occurring in the rocks. It is true
that small oil stains have been observed in some of the drill cores,