Coral Communities and Implications for Paleoenvironments: Silurian Heliolitine Corals in a Carbonate Ramp Setting, Canadian Arctic

Abstract

Heliolitine corals occur in the Ludlow-age Douro Formation on Somerset and neighboring islands. The corals occur in argillaceous carbonate rocks deposited on a regionally extensive ramp. Contemporaneous coral assemblages from different areas show marked differences in community characteristics that reflect a range of paleoenvironments, some more suited and others less suited to the heliolitines. Some of the paleoenvironmental differences are implied more strongly by the coral assemblages than by regionally subdued variations in enclosing carbonate facies. Optimal conditions for heliolitine corals in the region were apparently in a «mid-ramp» position, as suggested by numerically abundant, diverse, low-dominance species assemblages, with a greater proportion of flat-based and discoid colonies