Abstract
DURING the late Pleistocene the hydrography of the Eastern Mediterranean underwent severe changes in response to climatic fluctuations. Among the most striking of these changes were periods of deep water stagnation. Episodes of oxygen depletion are indicated by the presence of layers of dark sapropelitic muds enriched in organic carbon, devoid of the remains of benthic organisms1–4. While stagnant conditions prevailed in the deep basin, the water column above 1,000–800 m remained ventilated, and cores raised above this depth do not contain sapropels4–6. Several theories have been proposed to explain the past stagnations. They all use a mechanism which stabilises the water column by forming a steep density gradient in the upper waters. In this way the vertical mixing, and hence the ventilation, are retarded, oxygen is depleted in the deep water and stagnation commences. Olauson's theory7, whereby influx of freshwater leads to reduced surface density and the interruption of normal vertical circulation, is the most widely accepted at present. This theory is supported by recent studies8–10, which use measurements of oxygen isotope composition in shells of planktonic foraminifera. These studies demonstrate that many of the sapropels correspond to δ18O minima, suggesting freshwater influx, and thus a reduced upper water salinity at the time of the sapropel formation. Moreover, the epipelagic species record greater depletion of 18O than the mesopelagic species, indicative of the establishment of salinity and density gradient in the upper waters10. Using a similar approach we have attempted to investigate in detail the hydrographie changes associated with the deposition of the most recent sapropel, which took place about 7,000–9,000 yr BP6.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Bradley, W. H. Science 88, 376–379 (1938).
Kullenborg, B. Medd. Oceanogr. Inst. Goteborg 21, 1–38 (1952).
Ryan, W. B. F. in The Mediterranean Sea (ed. Stanley, D. J.) 149–169 (Dowden, Hutchmson & Ross, Stroudsburg, 1972).
van Straaten, L. M. J. U. in The Mediterranean Sea (ed. Stanley, D. J.) 631–643 (Dowden, Hutchmson & Ross, Stroudsburg, 1972).
Hesse, R. von Rad, U. & Fabricus, F. H. Mar. Geol. 10, 293–355 (1971).
Stanley, D. J. Nature 274, 149–152 (1978).
Olauson, E. Rep. Swedish-Sea Expdn 1947–1948 8, 353–391 (1961).
Thunell, R. C., Williams, D. F. & Kennett, J. P. Mar. Micropaleont. 2, 129–135 (1977).
Vergnaud-Grazzini, C., Ryan, W. B. F. & Cita, M. B. Mar. Micropaleont. 4, 353–370 (1977).
Williams, D. F., Thunell, R. C. & Kennett, J. P. Science 201, 252–254 (1978).
Nir, Y. Geol. Surv. Israel Rep. MG/73/2 (1973).
Luz, B. & Bernstein, M. Mar. Micropaleont. 1, 307–323 (1976).
Luz, B. & Perelis-Grossowicz, L. Isr. J. Earth Sci. (in the press).
Shackleton, N. J., Wiseman, J. D. H. & Buckley, H. A. Nature 242, 177–179 (1973).
Vergnaud-Grazzini, C., Paleogeogr. Paleoclimatol. Paleocol. 20, 263–276 (1976).
Erez, J. Nature 273, 199–202 (1978).
Reiss, Z., Merling-Reiss, P. & Moshkovitz, S., Isr. J. Earth. Sci. 20, 141–177.
Shackleton, N. J. & Vincent, N. J., Mar. Micropaleont. 3, 1–13 (1978).
Williams, D. F., Sommer, M. A. & Bender, M. L. Earth planet. Sci. Lett. 36, 391–403 (1977).
Cita, M. B. et al. Quat. Res. 8, 205–235 (1977).
Deuser, W. G. & Hunt, J. M., Deep-Sea Res. 16, 221–225 (1969).
Kroopnick, P., Deep-Sea Res. 21, 211–227 (1974).
Shackleton, N. J. Coloq. Int. C.N.R.S. 219, 203–209.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
LUZ, B. Palaeo-oceanography of the post-glacial Eastern Mediterranean. Nature 278, 847–848 (1979). https://doi.org/10.1038/278847a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/278847a0
This article is cited by
-
Geochemistry of the Aptian bituminous limestones in Gümüşhane area, Eastern Black Sea region: new insight into paleogeography and paleoclimate conditions
Acta Geochimica (2023)
-
Glacial–Holocene salinity changes in the Mediterranean Sea: hydrographic and depositional effects
Nature (1989)
-
Uptake of inorganic carbon and internal carbon cycling in symbiont-bearing benthonic foraminifera
Marine Biology (1987)
-
Occurrence of long-chain alkan-diols and alkan-15-one-1-ols in a quaternary sapropel from the Eastern Mediterranean
Lipids (1983)
-
After the deluge: Mediterranean stagnation and sapropel formation
Nature (1982)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.