A major portion of Florida's Gulf of Mexico coastline is a siliciclastic, sand-starved, low-wave-energy system dominated by marshes that face the open sea. Within a 65-km sector along this 300-km-long, open-marine marsh coast, four distinctly different morphological sectors have been identified: 1) berm-ridge marsh shoreline, 2) marsh peninsula shoreline, 3) marsh archipelago shoreline, and 4) shelf embayment shoreline. The underlying Paleogene limestone bedrock topography results from karstification and dissolution processes. This antecedent topography and distribution of actively discharging freshwater springs affect sedimentary processes, facies, and stratigraphic units. Within the inner continental shelf, very little of the marsh stratigraphy or large oyster bioherms is preserved. Only those sediments that have accumulated within bedrock depressions or sinkholes have the best chance for long-term retention. Thus, a condensed stratigraphic section is produced.