Chemosynthesis: An Alternate Hypothesis for Carboniferous Biotas in Bryozoan/Microbial Mounds, Newfoundland, Canada

Abstract

Fossil tubes, stressed high-abundance low-diversity faunas, and abundant, low-temperature, hydrothermal mineralisation occur in Lower Carboniferous bryosoan/microbial carbonate mounds in southwestern Newfoundland, Canada. These occurrences, set in a rift-valley setting that was tectonically active during the Carboniferous, were previously regarded as marginal marine deposits laid down in subtidal, schisohaline environments adjacent to a rocky shoreline. We suggest that they may, instead, have formed by chemosynthetic processes at low temperature marine vents at a depth of 100 m, or greater