sediments have built up on the ancient core of today’s barrier islands
(called the Silver Bluff Formation by geologists). These Holocene
sediments, as they are known to geologists, are mostly sand deposited
by winds, waves and currents.
process of sedimentation is accompanied by erosion of sand from
the islands by the same processes that deposit it elsewhere. This
is called the coastal
sand-sharing system, and it results in a constantly changing
the prevailing coastal currents are from north to south, erosion
most often occurs on the northern ends of islands and deposition
most often occurs on the southern ends. The south end of Sapelo
Island has grown significantly over just the last 50 years.
adapted from Hoyt,