6533b7d0fe1ef96bd125ad09

RESEARCH PRODUCT

Succession et remplacements de communautés à brachiopodes en régime de sédimentation discontinue (Jurassique Moyen, Bourgogne, France)

subject

description

Abstract Sequence stratigraphy throws a new and seminal light on the fossil record and helps in determining the respective role played by external control (community replacement) and internal control (paleoecological succession) in the temporal “train” of marine benthic paleocommunities. Five brachiopod-dominated communities (C1–C5) are recognized and their temporal “train” described, during the uppermost Bathonian-lower Callovian interval in Burgundy. The first series (C1–C3) exhibits a trend interpreted as a paleoecological succession and the next two (C3–C4, C4–C5) as community replacements. Within the scope of sequence stratigraphy, the paleoecological succession comes at the end of a transgressive system tract, during an episode of reduced sedimentation, while the first replacement occurs with a maximum flooding of the platform. Faunal condensations are generally coincident with paleoecological successions but can restrict their retrieval from the fossil record. Conversely community replacement results from an external event, substrate quality related, which represents a triggering ecological factor for benthic community transformations.