CHAPTER VII.

ECONOMIC GEOLOGY.

The substances to be considered in discussing the economic
geology of Graham island are coal, lignite, petroleum, oil-shale,
clay, building stone and limestone, and gold. These materials
are treated in the order given.

COAL:

Coal, of Cretaceous age, is found in the Haida formation
of the Queen Charlotte series. The coal occurrences may be
grouped on structural grounds in two basins; the Honna
basin in the southern part of the island, and the Yakoun basin
in the north-central part. In the Honna basin, anthracitic coal
is found at Cowgitz and in the Slatechuck valley in the vicinity
of Skidegate inlet; and coal of a somewhat similar kind occurs
near Yakoun lake. At Camp Anthracite a coal is found resem-
bling bituminous in appearance, but more like a low grade
anthracite in composition. The most important location in the
Honna basin is at Camp Robertson, where one seam of bitu-
minous coal has been exposed.

In the writer’s summary report for 1913, pages 36 and 48,
the statement was made that these exposures represented out-
crops of the same horizon, repeated by folding. Further work
has made it appear more probable that the horizon of Camps
Robertson and Anthracite, which doubtless are on the same seam,
is higher in the Haida formation than the horizon of the exposures
at Skidegate inlet and Yakoun lake.

Coal has been found at only one locality in the Yakoun basin,
at Camp Wilson, and the coal there is also bituminous.

Material of a coaly nature is recorded from the south shore
of Saltspring bay by Richardson,! and on the south shore of
Skidegate channel,? by Dawson. These occurrences are in an

1 Richardson, James, Geol. Surv., Can., Rept. of Prog., 1872-73, p. 60.
2 Dawson, G. M., Geol. Surv., Can., Rept. of Prog., 1878-79.