OPEN FILE REPORT NO. 80


 Tci Citronelle Formation The Citronelle Formation is widespread in the Gulf Coastal
Plain. The type section for the Citronelle Formation, named by Matson (1916), is near
Citronelle, Alabama. The Citronelle Formation grades laterally, through a broad facies
transition, into the Miccosukee Formation of the eastern Florida panhandle. Coe (1979)
investigated the Citronelle Formation in portions of the western Florida panhandle. The
Citronelle Formation is a siliciclastic, deltaic deposit that is lithologically similar to, and time
equivalent with, the Cypresshead Formation and, at least in part, the Long Key Formation
(Cunningham et al., 1998) of the peninsula. In the western panhandle, some of the sediments
mapped as Citronelle Formation may be reworked Citronelle. The lithologies are the same and
there are few fossils present to document a possible younger age.
 The Citronelle Formation consists of gray to orange, often mottled, unconsolidated to
poorly consolidated, very fine to very coarse, poorly sorted, clean to clayey sands. It contains
significant amounts of clay, silt and gravel which may occur as beds and lenses and may vary
considerably over short distances. Limonite nodules and limonite-cemented beds are common.
Marine fossils are rare but fossil pollen, plant remains and occasional vertebrates are found.
 Much of the Citronelle Formation is highly permeable. It forms the Sand and Gravel
Aquifer of the surficial aquifer system.

 Tmc Miccosukee Formation The Miccosukee Formation, named by Hendry and Yon
(1967), is a siliciclastic unit with a limited distribution in the eastern panhandle. It occurs in the
Tallahassee Hills from central Gadsden County to eastern Madison County, often capping hills.
The Miccosukee Formation grades to the west, through a broad facies transition, in central
Gadsden County into the Citronelle Formation. The Miccosukee Formation is a prodeltaic
deposit.
 The Miccosukee Formation is composed of grayish orange to grayish red, mottled, poorly
to moderately consolidated, interbedded clay, sand and gravel of varying coarseness and
admixtures (Hendry and Yon, 1967). The unit is relatively impermeable but is considered a part
of the surficial aquifer system (Southeastern Geological Society, 1986).

 Tc Cypresshead Formation The Cypresshead Formation named by Huddlestun (1988),
is composed of siliciclastics and occurs only in the peninsula and eastern Georgia. It is at or near
the surface from northern Nassau County southward to Highlands County forming the peninsular
highlands. It appears that the Cypresshead Formation occurs in the subsurface southward from
the outcrop region and similar sediments, the Long Key Formation, underlie the Florida Keys.
The Cypresshead Formation is a shallow marine, near shore deposit equivalent to the Citronelle
Formation deltaic sediments and the Miccosukee Formation prodeltaic sediments.
 The Cypresshead Formation consists of reddish brown to reddish orange, unconsolidated
to poorly consolidated, fine to very coarse grained, clean to clayey sands. Cross bedded sands
are common within the formation. Discoid quartzite pebbles and mica are often present. Clay
beds are scattered and not really extensive. In general, the Cypresshead Formation in exposure
occurs above 100 feet (30 meters) above mean sea level (msl).
 Original fossil material is not present in the sediments although poorly preserved molds
and casts of mollusks and burrow structures are occasionally present. The presence of these
fossil "ghosts" and trace fossils documents marine influence on deposition of the Cypresshead
sediments.