Database for the geologic map of pre-Middle Jurassic basement rocks beneath the Coastal Plain in Florida

Much of the southeastern United States, including all of Florida, is covered by flat-lying sedimentary strata of the Atlantic and Gulf Coastal Plains which have accumulated since Middle Jurassic time. The pre-Middle Jurassic rocks that underlie these coastal plains in Florida, here collectively referred to as “basement,” are known only from a relatively small number of boreholes. This scientific investigations map presents an interpretation of the basement geology in a 1:1,000,000-scale subsurface geologic map with supporting text, data, and figures. The subsurface mapping methodology integrates petrographic, geochronological, thermochronological, geochemical, and mineralogical analyses of drill cores and cuttings in the context of regional geophysical data. Possible applications of this database relate to essential mineral, energy, and groundwater resources. The pre-Middle Jurassic basement rocks are much less permeable than overlying sediments composing the coastal plain aquifers. The boundary between pre-Middle Jurassic rocks and overlying coastal plain sedimentary units is thus an important boundary for the flow of groundwater in coastal plain aquifers. Radiogenic, heat-producing granites insulated by coastal plain sediments are potential sources of low-temperature geothermal energy. Buried early Mesozoic rift basins are potential energy resources for natural gas and are also relevant for applications such as deep supercritical carbon dioxide (CO2) storage. The basement geologic framework is also pertinent for infrastructure and engineering applications such as seismic-hazard assessment and the siting of critical facilities such as nuclear power stations.