100

The third group of coal seams is exposed in a cut 60 feet farther east.
Here is a 12-inch seam of firm, clean coal with several, parallel, 3-inch
Seams over a width of 4 feet. These outcrops are only a short distance
from the fault contact of the coal-bearing sediments with the older under-
lying volcanic and sedimentary rocks (See Figure 11). The upward exten-
sions of these groups of coal seams were seen to outcrop for several hundred
feet farther up the precipitous slope.

The coal on this property is soft and soils the fingers, and has a
roughly cubical fracture where it is not sheared. Its low content of
volatile matter is typical of anthracitic coal, but it has passed beyond the
anthracite stage and falls into that class of coal known as super-anthracite,
whose heating value is lower than that of anthracite.

DESCRIPTIONS OF MARL DEPOSITS
Robinson Lake Marl (16)

Robinson Lake is 6 miles northeast of Hazelton, a few hundred feet
from the Nine Mile Mountain road. The lake is 1,900 feet long from
north to south with an average width of 400 feet and a maximum width
of 900 feet. It is a clear water lake, in few places over 5 feet deep except
in the centre where there is 30 feet of water. Everywhere in shallow
water the lake bottom consists of a thick deposit of soft white to erey
marl. The marl is concealed in many places by a heavy growth of Chara,
a plant in which lime is deposited in the cells and cell walls. These plants
have evidently contributed largely to the deposition of the marl, but some
shell remains were also observed. At the north end of the lake an inflowing
stream flowing through low, marshy land has supplied dark vegetable
matter, which is deposited locally with the marl. The best quality of
white marl is found at the south, or outlet, end of the lake. Here a 12-foot
pole pushed down into the deposit does not reach the bottom of it.
Elsewhere the calcium carbonate layer is at least 6 feet thick, as a pole
thrust into it pushes down that far before striking any resistance and
comes up white covered.

The marl is of economic importance because of its value as a land
dressing. It could be readily mined from the lake bottom by using
a suction pump or small dredge.