RLLS GRAHAM ISLAND 29 B

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Chuck creek the black and grey shales are sometimes much crushed.
They become associated with heavy masses of the grey, coarse, conglom-
erate that forms the shore southward to the end of the tramway in
Anchor cove which leads up to the Anthracite mine. This part of the
shore is very rough. The rocks are much broken with oceasional dips
both to the east and west, and dykes of dark green diabase cut both shale
and conglomerate. Between this part of the shore and the Cowgitz mine,
a distance of three-fourths of a mile west in a straight line, the black and
grey shales again appear and are cut by dykes. The coal is in close prox-
imity to the underlying igneous rocks which extend thence westward to
the west side of the island. The rocks at the mine containing the coal
are much broken up and crushed, and the original lignite of the formation
has been converted to the variety of anthracite there found. This is due
to heat induced by pressure of the shales and sandstones against the Pre-
Cretaceous igneous rock mass at the back. In fact, so great has been the
crushing strain at this place that much of the coal, when mined, is found
in the form of powder, and is quite useless for economic purposes, while,
as in other outcrops on the island, the coal and black shale are so closely
mixed that their separation 1s almost impossible.

Mining has been carried on at this place at intervals for many years.
The original company, apparently formed in Victoria in 1865, was the
Queen Charlotte Coal Mining Co. A somewhat full description of the
earlier work done at the mine is given in Mr. Richardson’s report (1872)
and Dr. Dawson’s report, 1878-79. The last attempt to mine this deposit
Seems to have been made about fifteen years ago. None of these efforts
has ever been attended with much success. The workings have long since been
abandoned, and the tunnels having fallen in, any exploration of them at the
present time would be very dangérous. In view of this fact, and be-
cause no information other than already in our possession seemed obtain-
able, no detailed examination of this mine was made during our visit.
The approaches along the old tram-road from the wharf to the mine are
already thickly grown over with bushes and will require considerable
clearing before the place can be accessible.

Along the valley of Slate Chuck creek a band of sandstone with areas
of black slate, more massive than the ordinary slates of the shore section,
comes in and extends northwestward. As described by Mr. Richardson
(Rep. Prog. 1872-73, p. 61), ‘‘the shale occurs in lenticular patches of
two to three feet in the thickest part and from eight to twenty
feet long which are interstratified with a light-grey, not very
hard sandstone. In the patches occur an abundance of flattened

stems and leaves, sometimes infiltrated with a greenish mineral and

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