CLAY MINERALOGY OF THE EUREKA SOUND AND BEAUFORT FORMATIONS, AXEL HEIBERG AND WEST CENTRAL ELLESMERE ISLANDS, EASTERN CANADIAN ARCTIC ARCHIPELAGO

In the Late Cretaceous and Tertiary strata of the Eureka Sound and Beaufort Formations on Axel Heiberg and west central Ellesmere Islands, kaolinite and illite are the dominant clay minerals, with minor to major amounts of smectite and random mixed-layers, and trace amounts of vermiculite and chlorite. Smectite and associated mixed-layers in the basal Eureka Sound Formation formed by in situ alteration of volcaniclastic material, whereas mixed-layers in the deltaic-alluvial deposits probably result from in situ paleosol formation. These strata are a likely source rock for the younger Tertiary and Quaternary Arctic Ocean sediments.