ABSTRACT
The northwestern coast of Egypt, a stable carbonate platform, is characterized by the presence of successive coastal ridges that extend parallel to the present shoreline and are composed of alternations of marine, aeolian sediments and palaeosols. These deposits were easily traced, analyzed for stable isotopes, dated and correlated with tectonically active raised coast in Greece, Eastern Mediterranean Basin. Samples representing the Nile Delta offshore Quaternary succession were also used to determine the percentages of organic carbon and benthonic foraminifera. The latter were analyzed for stable isotopes, and serve to indicate the climatic changes that can be correlated with those detected from the Eastern Mediterranean stratigraphy.
This study reveals the presence of four major climatic periods in close relationship to the changes in marine level. Each climatic period consists of a warm-wet phase followed by a cold-arid one. The warm-wet phases are characterized by negative oxygen and carbon isotopes, the deposition of marine sediments with a high frequency of benthonic foraminifera and/or the development of palaeosols with a high content of organic carbon. The cold-arid phases are characterized by positive oxygen and carbon isotopes and aeolian sedimentation, with a low benthonic foraminifera and organic carbon in the Nile Delta sediments.
The suggested climatic periods are correlated with isotope stages 9 to 1 and are related to aminozones G, E, C and A of the Middle to Late Quaternary.
