Several types of diapiric structures were studied in the zone between the Nile deep-sea fan and the Eratosthenes seamount in the SE Mediterranean Sea. The study discovered four stages in the structural evolution of the diapiric features, starting as a domal piercement structure, and developing into initial basin as seawater dissolution starts to effect the diapiric salt. Subsequently V-shaped, and then mature, U-shaped basins formed as products of dissolution, sedimentary collapse and sediment deposition. The structures-both protrusions and depressions, are aligned along discrete lineaments, most of them trending NE-SW and a few-NW-SE. The NE-SW lineaments are probably a series of normal faults and the NW-SE ones seem to be strike- slip faults. The development of extensional structures on the underthrust edge of the African Plate, as it approaches the subduction zone, are commonplace in the Mediterranean and elsewhere, and the occurrence of normal faults in this area is compatible with the intensive subsidence of the Eratosthenes Seamount in the Plio-Pleistocene. The lithostatic load of the Nile deep-sea fan could have contributed to the subsidence and thus enhanced the diapirism in the SE Mediterranean.
Bibliographical noteFunding Information:
We are grateful to Zvi Garfunkel and to Israel Zak from the Hebrew University, Jerusalem, for fruitful discussions, To David A. Ross of Woods Hole Oceanographic Institution for his seismic data from the eastern Mediterranean, to Bruno Vendeville from the Bureau of Economic Geology, University of Texas at Austin, and an anonymous reviewer for their thorough and helpful reviews, to Hanna Bernard and to Arik Golan from the National Institute of Oceanography, Haifa, for dexterous technical assistance, and to the Captain and Crew of the R/V Shikmona. This research was supported by grant No. 92-00392 from the United States-Israel Binational Science Foundation (BSF), Jerusalem, Israel. Financial support of the Israel Ministry of Energy is gratefully acknowledged.
- SE Mediterranean
- salt diapirs
- structural extension
- tectonic collision
ASJC Scopus subject areas
- Geochemistry and Petrology