Geologic units in Clinch county, Georgia

Pleistocene-Pliocene sands and gravels (Pleistocene-Pliocene) at surface, covers 80 % of this area

Includes, in part, Sunderland, Coharie, and Brandywine "Formations" of Cooke, 1939

Wicomico Shoreline Complex - marsh and lagoonal facies (Pleistocene) at surface, covers 19 % of this area

Wicomico Shoreline Complex - marsh and lagoonal facies

Miccosukee Formation (Neogene) at surface, covers 0.4 % of this area

Miccosukee Formation

Undifferentiated sediments (Pliocene/Pleistocene) at surface, covers < 0.1 % of this area

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 sediments 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 organics are present in these sediments. The undifferentiated Tertiary-Quaternary sediments are part of the surficial aquifer system.