The Bahama-Banks model, where "high-energy" carbonate-sand bodies are associated with shelf edges or pronounced shelf breaks, is often invoked in the interpretation of ancient limestones, but the Yucatan shelf provides another model which may be pertinent to the analysis of many Gulf Coast Mesozoic carbonates. Off the northeastern Yucatan Peninsula several types of bioclastic and lithoclastic carbonate sands and gravels have been deposited on the inner shelf, and longshore transport has produced a barrier island-lagoon complex adjacent to the coast.

A partly submarine, partly subaerial belt of oolitically coated sand parallels the coast from the Caribbean side of Isla Cancun northward to beyond Isla Blanca. This belt of Holocene ooids is thickest on its landward edge, where coastal dunes accumulate. The carbonate-dune deposits are rapidly lithified, enhancing their chance of preservation and creating topographic features that have profound influence on subsequent subaqueous sedimentation. Effective porosity in these Holocene dune limestones ranges from 26 to 36%.

The oolitic sand passes seaward into uncoated bioclastic and lithoclastic sand gravel. Periodic storm waves wash ooids landward into the muddy lagoon behind the Isla Blanca dune and beach-ridge barrier.

Preservation of the carbonate facies deposited on the inner shelf of northeastern Yucatan would create stratigraphic traps in the most updip carbonate grainstones. Carbonate mudstones of the coastal lagoons would be both permeability barriers and source rocks for hydrocarbons.

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