STRATIGRAPHY AND SEDIMENTOLOGY OF UPPER SILURIAN ROCKS, NORTHERN SOMERSET ISLAND, ARCTIC CANADA

Late Silurian subtidal, intertidal, and supratidal rocks are widely and complexly associated along the north coast of Somerset Island. The intertidal-supratidal rocks contain considerable quantities of texturally and mineralogically immature, sand-sized, detrital quartz, feldspar, and mica, apparently derived from nearby. The subtidal rocks also commonly contain large amounts (up to 50%) of clay- to silt-sized quartz, dolomite, muscovite, and clay minerals. The detrital sediment and the close association of subtidal and intertidal-supratidal rocks suggest that these Late Silurian rocks are part of a basin-margin succession flanking a low-lying land mass situated to the north and northeast. A general increase in the proportion of detrital sediment and greater persistence of near-shore carbonate facies toward the east suggest either greater proximity to a shoreline or a more persistently elevated land area in that direction.