Petrological, palynological and geochemical characteristics of Eureka Sound Group coals (Stenkul Fiord, southern Ellesmere Island, Arctic Canada)

Abstract

Late Paleocene/Early Eocene coal-bearing strata are widespread across the Canadian Arctic Archipelago. Laterally continuous seams of substantial thickness are present in the Iceberg Bay Formation, Eureka Sound Group, at Stenkul Fiord, Ellesmere Island. Sixty-four coal seams with a cumulative thickness of 53 m of coal occur in a 450 m sequence. The investigation of the composite section is based on examination of 19 samples from seams thicker than 1 m and 7 samples from marker seams used for correlation purposes. The coals consist predominantly of wood-derived huminite macerals (79–98 vol%). Structured huminite macerals are dominant in the top part of the section whereas detrital components are abundant in the lower part. The liptinite fraction is dominated by sporinite and cutinite (1–9 vol%). Inertinite content is very low except at the base of the section (0–14 vol%). Reflectances determined on eu-ulminite (0.36–0.43% R o), geochemical parameters, and Thermal Alteration Indices indicate that the coals are of lignite to subbituminous rank. The dominance of diterpanes and the abundance of Taxodiaceae and Pinaceae pollen suggest that most of the organic matter is of gymnospermous origin. Pinaceae pollen is abundant in the lower part of the section and Taxodiaceae is abundant in the upper part. The abundance of angiosperm pollen in most of the section suggests, however, that angiospermous plants were significant members of the flora. The depositional environment for the Iceberg Bay Formation coals at Stenkul Fiord is that of forested swamps on an alluvial plain. Pollen assemblages indicate a Late Paleocene/Early Eocene age for the section, and a temperate moist climate.