Fabric transitions from shell accumulations to reefs: an introduction with Palaeozoic examples

Article in Edited Volumes

Publication Details

Author(s): Álvaro JJ, Aretz M, Boulvain F, Munnecke A, Vachard D, Vennin E
Editor(s): Geological Society London
Title edited volumes: Geological Society, London, Special Publication
Publishing place: London
Publication year: 2007
Title of series: Palaeozoic Reefs and Bioaccumulations: Climatic and Evolutionary Controls
Volume: 275
Pages range: 1-16
ISBN: 9781862392212
Language: English


One unresolved conceptual problem in some Palaeozoic sedimentary strata is the boundary between the concepts of ‘shell concentration’ and ‘reef’. In fact, numerous bioclastic strata are transitional coquina-reef deposits, because either distinct frame-building skeletons are not commonly preserved in growth position, or skeletal remains are episodically encrusted by ‘stabilizer’ (reef-like) organisms, such as calcareous and problematic algae, encrusting microbes, bryozoans, foraminifers and sponges. The term ‘parabiostrome’, coined by Kershaw, can be used to describe some stratiform bioclastic deposits formed through the growth and destruction, by fair-weather wave and storm wave action, of meadows and carpets bearing frame-building (archaeocyaths, bryozoans, corals, stromatoporoids, etc.) and/or epibenthic, non-frame-building (e.g. pelmatozoan echinoderms, spiculate sponges and many brachiopods) organisms.

This paper documents six Palaeozoic examples of stabilized coquinas leading to (pseudo)reef frameworks. Some of them formed by storm processes (generating reef soles, aborted reefs or being part of mounds) on ramps and shelves and were consolidated by either encrusting organisms or early diagenesic processes, whereas others, bioclastic-dominated shoals in barrier shelves, were episodically stabilized by encrusting organisms, indicating distinct episodes in which shoals ceased their lateral migration.

FAU Authors / FAU Editors

Munnecke, Axel Prof. Dr.
Professur für Paläontologie (Schwerpunkt Faziesanalyse)

External institutions with authors

LILLE 1 University - Science and Technology
Universidad Complutense de Madrid (UCM)
Université Bourgogne Franche-Comté
Université Toulouse III - Paul Sabatier
University of Liège (ULg) / Université de Liège

How to cite

Álvaro, J.-J., Aretz, M., Boulvain, F., Munnecke, A., Vachard, D., & Vennin, E. (2007). Fabric transitions from shell accumulations to reefs: an introduction with Palaeozoic examples. In Geological Society London (Eds.), Geological Society, London, Special Publication. (pp. 1-16). London.

Álvaro, José-Javier, et al. "Fabric transitions from shell accumulations to reefs: an introduction with Palaeozoic examples." Geological Society, London, Special Publication. Ed. Geological Society London, London, 2007. 1-16.


Last updated on 2019-20-07 at 07:11