LEVANTINE SEA-NILE CONE LITHOSTRATIGRAPHIC EVOLUTION - QUANTITATIVE-ANALYSIS AND CORRELATION WITH PALEOCLIMATIC AND EUSTATIC OSCILLATIONS IN THE LATE QUATERNARY

The complexity of the Late Quaternary lithostratigraphic record in the southeastern Mediterranean has been noted in previous studies. The present investigation attempts to further resolve the depositional evolution and cyclic nature of sedimentary sections in 65 piston and gravity cores collected on the Nile Cone and adjacent areas. The availability of numerous radiocarbon dates and detailed sedimentological analyses now enable us to more precisely identify the six lithostratigraphic units that comprise three uppermost Late Quarternary cycles. It can be demonstrated that these six units, covering a period of time from about 55,000 years B.P. to the present, are correlatable across the study area. Herein, the changes of lithofacies with time are determined quantitatively by using multivariate and univariate analyses of eight sediment types and sedimentation rates. A statistical treatment that includes cluster and principal component analyses allows definition of two major assemblages of cores: pelagic (suspensite) and mass flow (gravitite) types. An attempt is made to relate the evolution in time of sedimentary patterns with major climatic and eustatic changes affecting the eastern Mediterranean. All data considered here indicate that each complete cycle correlates with a major eustatic change, and that differences in successive cycles coincide broadly with variations in successive paleoclimatic trends. Cycles 1 (Late Wisconsin to Holocene) and 3 (Middle to Late Wisconsin), display comparable sedimentary patterns and record a general warming-rise in sea level. In contrast, cycle 2 (Late Wisconsin), lithologically distinct from the former, is a response to a major cooling-eustatic lowering trend. Both the approach used in this investigation and the results obtained may be applicable to the stratigraphic study of older eastern Mediterranean sections and other oceans. © 1979.