Marine Carbonate Factories: Sedimentation Patterns and Sequence Stratigraphy

John Reijmer - Vrije Universiteit Amsterdam

The carbonate factories model, as defined at the beginning of this century, provides a subdivision of marine carbonate sediment production-systems based on the style of carbonate precipitation. The main factors controlling marine carbonate precipitation are light, water temperature, nutrients, salinity, substrate and carbonate saturation. Site-specific controls influencing the systems comprise ocean currents, upwelling and non-upwelling systems, ocean-atmosphere systems, atmospheric systems, shallow-water dynamics, and terrestrial sediment and water input.

The sequence stratigraphic patterns differ for the individual factories. The Tropical factory being light dependent is characterized by higher sediment production when the platform tops are flooded (highstand shedding). It displays decoupled sediment wedges with the partial infill of accommodation in the shallow-water realm and major sediment export towards the slopes and surrounding basins. The Cold-Water Coral factory is marked by in situ production and deposition with limited sediment export forming single cold-water coral spots or sediment accumulation ridges. The Cool-Water factory has a siliciclastic equivalent style of sediment distribution with lowstand-dominated, shelf edge wedges and a shaved-off shelf during sea-level highstands. Slope shedding marks the Microbial factory in which sediment production occurs within the upper slope realm of the flat-topped platforms both during highstands and lowstands in sea-level. This allows for fairly continuous sediment production exhibiting minor impact of sea-level changes, but with progradation, aggradation, and retrogradation of the system being only limited by local environmental changes. Planktic factory sediment production may vary in accordance with variations in sea-level providing time lines, systems tracts boundaries, in the pelagic realm.

In summary, each factory is branded by an individual set of features, e.g. production window, sediment production and export, morphologies and slopes. It is this unique set of variables marking each factory that determines the factory-dependent response to small-scale and large-scale environmental changes through space and time as shown in the sequence stratigraphic development.