The Campbellton Formation, New Brunswick, Canada: A Sedimentological and Paleoenvironmental Description of an Early Devonian (Emsian) Vegetated Landscape

Abstract

The Campbellton Formation, ~1 km thick, has long been recognized for early plants, arthropods, and fishes. The sedimentology of two basins is described with six facies associations to provide a framework for the fossil assemblages. The western basin contains aquatic fauna and coastal flora within a basal rhyolite breccia and coastal deltaic strata, and a braided river facies association is also present. Lower eastern basin strata primarily comprise lacustrine facies, where a thick marginal association deposited by sediment-laden underflows contains a lake-side plant assemblage. Other lacustrine associations include a fine-grained association in areas with restricted circulation, and a near-shore association. Upwards, a plant-rich fluvial landscape had wide sandstone and conglomerate channels and high-diversity wetlands containing terrestrial arthropods. A proximal alluvial facies association with hyperconcentrated flows contains plants and Prototaxites, possibly from adjoining uplands. All plants groups were well-established throughout the formation, with no apparent landscape partitioning between groups.