Description
Sediment samples from the Georgia continental shelf have been collected from a statistically viable sampling grid. Eighty-eight samples were processed for textural analyses, based on 0.25 phi sieve data. The mid-shelf area is covered by medium to coarse sand, evenly distributed with no linear trends. Scattered patches of mud exist, and the fauna of these patches indicates they are relict lagoon or marsh deposits. Areas of fine sand are located on the shelf-edge and in two distinct lobes extending seaward from the coast. These lobes constitute the so-called boundary between fine, nearshore "Recent'' sediments and coarser, mid-shelf, Pleistocene or "relict" sediments. The position of the lobes suggests that the fine material was supplied by the Savannah and the Altamaha Rivers; and this position, combined with available current, wind and wave data, further suggests that a net southerly longshore drift dominates the current regime in the area. A ridge of low relief extends from Sapelo Island southeast across the shelf, and appears to be a significant factor in the control of bottom currents. Constant reworking of the shelf sediments by current action has altered most of their original textural characteristics. Thus, reference to these sediments as ''relict" is misleading. They are better described as palimpsest sediments.
