114

rections of the two periods of major folding. The fissures are
thus not strictly parallel to the general strike of the pre-Creta-
ceous and post-Cretaceous folding; but it should be pointed
out that the dykes plotted are nearly all from the vicinity of
Skidegate inlet, and there is reason to suspect a bending of the
folds towards the west in this region.

Figure 10. Chart showing strikes of thirty-three dykes (Etheline), mostly
around Skidegate inlet.

HISTORICAL GEOLOGY.

The first geological event of which there is any record in
the rocks studied on Graham island was a long stage of marine
sedimentation. This sedimentation took place under very