The West Florida continental margin is a vast accumulation of over 500,000 km of Mesozoic to Recent carbonates and evaporites. Carbonate and evaporite domination is primarily due to the fact that the region has been cut off from clastic sedimentation since the Jurassic. Surface facies are now being deposited under semitropic and temperate climates. A relict quartz-dominated sand band which makes up the beaches and innermost shelf is the product of lower stands of sea level when the Tertiary terrace deposits of the central Florida hinterland were eroded by rejuvenated streams which carry little load during highstands. The band is gradually undergoing carbonatization as it is now cut off from any clastic source and the only components being added are mollusk shells and frag ents. The shelf is dominated by molluscan shell hash with few corals or coralline algae. Even the few active patch reefs like the Florida Middle Ground have sediments dominated by molluscan debris and are barely surviving.

The slope facies resembles a deep-sea foraminiferal ooze. Transition from the margin to the deep Gulf of Mexico is from shallower ooze to deeper clastic lutite. Slope sediments are accumulating at the relatively rapid rate of about 20 cm/1,000 years. Mass wasting has occurred on the slope and karstification is evident in the stratigraphy of the shelf. While the West Florida margin surface facies are different from those of the more intensively studied coral reefs and banks, they may have many significant analogs in the ancient and warrant more attention.

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