Comparative sedimentology and palaeoecology of Oxfordian Upper Jurassic coral-dominated reefs of England, France, Italy and Switzerland has been used to: 1 identify and characterize different types of Late Jurassic coral reefs with regard to their litho- and biofacies| and 2 develop a depositional model for these reefs relating different reef types to each other within a palaeoenvironmental framework. Eight generic reef types and one associated reef facies are recognized. These are: I biostromal units dominated by platy microsolenids developed within clean limestone facies| II biostromal units dominated by platy microso!enids developed within marly fades| III reefal thickets dominated by tall dense phaceloid colonies developed within pure carbonate muds| IV<i> </i>microbial-coral reefs dominated by massive, branching ramose and phaceloid colonies| V large high diversity reefal units associated with large volumes of bioclastic material| VI small species-poor reefs developed within mixed carbonate/siliciclastic facies| VII microbial-coral reefs dominated by massive colonies| VIII reefal thickets dominated by branching ramose colonies with widely spaced branches developed amongst sand shoals and coral debris channels| and IX conglomerates rich in rounded coral fragments the reef associated facies. The development of these different constructional and compositional reef types is interpreted as being primarily a function of light intensity, hydrodynamic energy levels and sediment balance. A conceptual depositional model based on these parameters can be used to predict the spatial and temporal distribution of different reefal carbonates and highlight sedimentological and palaeoecological trends in reef development.
