VII.—On Plant Beds of Tertiary age in British Columbia

Extract

The following notes refer to the fossils found by me, during the last two years, in the Tertiary strata of Burrard Inlet, British Columbia, and to the enclosing rocks themselves. These fossils were derived from beds outcropping within four miles of the city of Vancouver. The strata consist of sandstones, mudstones, shales, and thin, irregular beds of lignite, of which last-named material a typical analysis by me gave—fixed carbon, 36.10; volatile combustible matter, 41.25; ash, 15 40; and hygroscopic water, 7.25 per cent. These lignite beds usually are only about an inch in thickness, but sometimes they run into pockets a foot or more in depth. There has been a considerable amount of money spent in putting down boreholes in this district in search of workable coal-seams, but, so far, without success; and the opinion of the writer is that no workable coal beds exist there, unless they occur in the Cretaceous beds, which are the coal-bearing deposits of Western North America, and probably underlie these strata. Early in 1894 I found the bed from which my earlier specimens were obtained. The lower part of this contains aquatic plants; above these are palm-leaves; and, again, above these salix, populus, and juglans (willows, poplars, and hickory). In the highest part of the deposit are palms and a few other leaves. The whole bed varies from four to eighteen inches in depth, and is underlain by a few inches of black shales, which contain many leaves that are for the most part very difficult to distinguish. This shale thins out in a few yards, and it would seem that the fossil bed runs out at the same point where the shale vanishes. I think that probably there existed, at the time when these fossils were deposited, a cove at this point, where the water was slack. The second bed which I worked in produces fewer fossils, but the veining is much more distinct. This deposit was only found in May, 1895. Where it was first opened the total thickness did not exceed one inch, which contained leaves of angiosperms, underlain by about one inch yielding fern-leaves. Underneath it was a bed of black shale two inches thick. Where it is now worked the upper part is at least six inches thick. It is curious to note in this deposit how at one end the hickory prevails; in the middle, poplars and willows; and at the other end, poplars alone: which would seem to point to the fact that these leaves were not carried any distance, but lie where they fell from trees overhanging the bank.