FLORIDA GEOLOGICAL SURVEY


 The permeable sands of the Cypresshead Formation form part of the surficial aquifer
system.

 TERTIARY-QUATERNARY SYSTEMS

 TOu Undifferentiated Tertiary-Quaternary Sediments These sediments are
siliciclastics that are separated from undifferentiated Quaternary sediments solely on the basis of
elevation. Based on the suggestion that the Pleistocene sea levels reached a maximum of
approximately 100 feet (30 meters) msl (Colquhoun, 1969), these sediments, which occur above
100 feet (30 meters) msl, are predominantly older than Pleistocene but contain some sediemnts
reworked during the Pleistocene. This unit may include fluvial and aeolian deposits. The
undifferentiated Tertiary-Quaternary sediments occur in a band extending from the Georgia-
Florida state line in Baker and Columbia Counties southward to Alachua County.
 These sediments are gray to blue green, unconsolidated to poorly consolidated, fine to
coarse grained, clean to clayey, unfossiliferous sands, sandy clays and clays. Organic debris and
disseminated organic are present in these sediments.
 The undifferentiated Tertiary-Quaternary sediments are part of the surficial aquifer
system.

 TOd Tertiary-Quaternary Dunes The dune sediments are fine to medium quartz sand
with varying amounts of disseminated organic matter. The sands form dunes at elevations
greater than 100 feet (30 meters) msl.

 TOuc Undifferentiated reworked Cypresshead Formation This unit is the result of
post depositional reworking of the Cypresshead siliciclastics. The sediments are fine to coarse
quartz sands with scattered quartz gravel and varying percentages of clay matrix.

 Pliocene Pleistocene Series

 TOsu Tertiary-Quaternary Fossiliferous Sediments of Southern Florida Mollusk-
bearing sediments of southern Florida contain some of the most abundant and diverse fossil
faunas in the world. The origin of these accumulations of fossil mollusks is imprecisely known
(Allmon, 1992). The shell beds have attracted much attention due to the abundance and
preservation of the fossils but the biostratigraphy and lithostratigraphy of the units has not been
well defined (Scott, 1992). Scott and Wingard (1995) discussed the problems associated with
biostratigraphy and lithostratigraphy of the Plio-Pleistocene in southern Florida. These
"formations" are biostratigraphic units.
 The "formations" previously recognized within the latest Tertiary-Quaternary section of
southern Florida include the latest Pliocene early Pleistocene Caloosahatchee Formation, the
early Pleistocene Bermont formation (informal) and the late Pleistocene Fort Thompson
Formation. This section consists of fossiliferous sands and carbonates. The identification of
these units is problematic unless the significant molluscan species are recognized. Often
exposures are not extensive enough to facilitate the collection of representative faunal samples to
properly discern the biostratigraphic identification of the formation. In an attempt to alleviate
the inherent problems in the biostratigraphic recognition of lithostratigraphic units, Scott (1992)