Sedimentary and tectonic features in the northwestern Gulf of Elat, Israel

Sedimentary phenomena and tectonic features in the northern Gulf of Elat were studied at water depths of 50 to 300 m. The study includes bathymetric mapping to a depth of 300 m and diving with a small submersible to 215 m. The bathymetric map displays two sedimentary terraces at depths of 50 to 90 m and 120 to 140 m, a few submarine canyons, a large fault, called here the Elat Fault and several small faults and slides. The dives with the submersible reveal the nature of the sedimentary cover and the character of the sedimentary terraces. They also permit direct observations of fossil reefs, submarine canyons, the Elat Fault and other small fractures and faults. We suggest that the sedimentary terraces represent Late Pleistocene sea level stands. The 50 to 90 m deep terrace probably was formed during stage 3 of the isotopic curve of Shackelton and Opdyke, about 50, 000 to 70, 000 years B.P., whereas the fossil reef at 120 to 140 m depth is correlated with the climax of the last glacial period, about 18, 000 years B.P. The submarine canyons and deltas also developed during the last glacial period. The Elat Fault has been active after the development of the 50 to 90 m depth terrace and probably displaced, in a left-lateral movement, some submarine features by 600 to 800 m.