COAL AND OIL-SHALE OF EARLY CARBONIFEROUS AGE IN NORTHERN CANADA - SIGNIFICANCE FOR PALEOENVIRONMENTAL AND PALEOCLIMATIC INTERPRETATIONS

Lower Carboniferous (Mississippian) coal beds and oil shale occur at several locations in northern Canada, In the northern Yukon Territory coal of semi-anthracite/anthracite rank (R(o)max % = 2.72-4.03) occurs in the Kayak Formation in the British Mountains and at Hoidahl Dome near the headwaters of Blow River. Farther south in the Liard Basin, Northwest Territories, coals of high volatile bituminous rank (R(o)max % = 0.67-0.80) are known to occur in the Mattson Formation. In the Arctic Islands thicker beds of the Emma Fiord Formation, the oldest unit in the Sverdrup Basin, contain thin coal seams and oil shale on Devon Island, near the southern edge of the basin and on Axel Heiberg and Ellesmere islands on the north side of the basin. Organic matter in the Devon Island section is at a low maturity level (R(o)m % = 0.26-0.50), whereas that from Ellesmere and Axel Heiberg has reached the level of meta-anthracite (R(o)max % = > 5.0). Depositional environments for these carbonaceous sediments were different. The coal-bearing Kayak strata accumulated in a coastal plain setting overlain transgressively by younger marine beds. The Mattson coal beds appear to have formed in a prograding delta, but coal and oil shale in the Emma Fiord were deposited in lacustrine environments in a rift basin. These Canadian occurrences resemble penecontemporaneous deposits in Svalbard and elsewhere, adjacent to the present-day Arctic Ocean. They formed at low latitudes where conditions were favourable for the preservation of carbonaceous matter. Prior to the opening of the Arctic Ocean basin in Mesozoic times, sites on the mainland were undoubtedly closer to sites in the Arctic Islands than they are today.