Holocene Depositional Patterns and Evolution in Alexandria's Eastern Harbor, Egypt

Abstract

Abstract This investigation focuses on sedimentological attributes and the litho- and chronostratigraphic framework of Holocene sediment core sections recovered in Alexandria's Eastern Harbor in Egypt, for many centuries the major port in the southeast Mediterranean. Holocene sediment trapped in the harbor, formed of marine calcareous sand, muddy sand, and mud, are examined to define major depositional patterns that developed before and after expansion of Alexandria in the 4th Century BC. Petrologic and radiocarbon data indicate that the harbor formed between two Pleistocene carbonate sandstone (kurkar) coastal ridges and was flooded by seawater during the transgression at about 8000 years before present (BP). Sediments accumulated at an average rate of 1–3 mm/y largely by wave- and wind-driven currents driving material from the Egyptian shelf into the high-energy basin. The association of distinct biological components, failed slump-like sediment strata, and important hiatuses (time gaps) record the epis...