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One of the features most commonly photographed from space, the Red Sea, always provides a powerful reminder that continents can be rifted apart, and that new oceans can form. Precise dating is difficult, but it appears that the Red Sea may have opened as little as 10 million years ago. The Red Sea itself (bottom) is floored by oceanic crust and has a mid-ocean-ridge spreading center, which is an extension of the Carlsberg Ridge in the Indian Ocean. The left fork in the picture is the Gulf of Suez; this is not apparently underlain by oceanic crust but is the tectonic continuation of the Red Sea rift. On the right, by contrast, is the Gulf of Aquaba (Akabar), which splays off diagonally. This is the expression of a quite different tectonic feature, a major left lateral strike slip fault that runs northward along the valley of the Jordan River through the Dead Sea and Lake Tiberias. These lakes occupy the sites of “pull apart” basins formed by parallel splays along the fault. The Sinai Peninsula, center, is occupied mostly by Precambrian metamorphic and igneous rocks. Coral reefs can be seen around the tip of the peninsula and at the mouth of the Gulf of Aquaba. STS-41G, October 1984. Picture #17-39-026. Right click here to download a high-resolution version of the image (8.77 MB)
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