Eogenetic Karst in Florida

Abstract

Florida’s karst constitutes some of Earth’s largest expanses of geologically young carbonate sedimentary deposits (shelly sediments, limestone and dolostone) with bare and covered karst. Because of the large population of Florida and the dependence of that population on carbonate aquifers, the karst of Florida is has been extensively investigated. This book synthesizes our knowledge about Florida karst, beginning with why Florida karst differs from older, telogenetic karst elsewhere in North America and the world.

Florida’s highly productive aquifers are part of an exemplary karst landscape, an extensive, mantled, geologically young carbonate terrain with dozens of first magnitude springs. Florida’s karst has provided water resources to an exploding population and fueled tourism, while creating or exacerbating problems such as sinkhole formation and saltwater intrusion.

The Florida Platform is low and flat and its geology has been dominated by sea-level fluctuations that have left behind a variety of carbonate strata and karst landforms ranging in age from Eocene to Recent. The eogenetic carbonates that comprise these aquifers were never deeply buried and, therefore, they have extensive primary porosity and well developed permeability, distinguishing them from older, telogenetic karst with little remaining primary porosity and very low matrix permeability. Florida’s karst is polygenetic, resulting in a complex array of karst features. The overlying siliciclastic sediments create an environment ripe for damaging sinkholes and other hazards.