ABSTRACT

Biogenic sedimentary structures, many of which are characteristic of particular depositional environments, are abundant among Holocene barrier island-salt marsh habitats of coastal Georgia. The major environments represented are: (1) beaches--including the shoreface, lower and upper foreshore, backshore, dunes, and washover fans, (2) salt marshes--comprised by the low marsh, high marsh, and barrens, and (3) estuaries and tidal streams--including channel deposits, mud flats, point bars, stream banks, and natural levees. Biogenic sedimentary structures in these environments consist of bioturbate textures and various tracks, trails, burrows, and dwelling tubes, and are produced chiefly by polychaetes, mollusks, echinoderms, decapods, amphipods, and insects. Such structures, either singly or as assemblages of lebensspuren, are not only diagnostic of most Holocene habitats but are also capable of being preserved in the rock record. Many of them have been documented in the Pleistocene of Georgia and Florida.