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Birth of the Red Sea

Peter Betts standing on exposed coral reef on the Farasan Islands

Peter Betts standing on exposed coral reef on the Farasan Islands in the southern Red Sea. The coral has been uplifted by upwelling of a salt diapir beneath the reef.

By Peter Betts

New evidence about the creation of the Red Sea has fundamentally changed how geologists understand the birth of oceans.

The full text of this article can be purchased from Informit.

The thin, solid crust on which we live represents only about 1% of the distance to the Earth’s centre: 5–10 km thick under the oceans and 25 –70 km thick under the continents. Yet its evolution and movement, and its interaction with the underlying mantle, give rise to almost all the geological events of significance to us, including earthquakes, volcanic eruptions and the formation of mineral deposits, oil and gas reserves, underground lakes, mountains and oceans.

The crust and upper mantle is broken into a jigsaw of moving tectonic plates. Their movement crushes them together, pulls them apart and makes them slide past each other. Some are pushed down under neighbouring plates in a process known as subduction.

While we have learned a lot about the movement of continents and what happens when they crash into one another, the formation of ocean crust – a major force that drives plate tectonics and regenerates the plates – remains one of the least understood processes related to plate tectonics.

However, recent research into the geology and geophysics of the Red Sea has overturned the conventional view that ocean crust formation is a continuous process whereby a rift opens in the ocean floor like a zipper and magma bubbles up from the underlying mantle to push it apart. Instead, seafloor formation actually happens in bursts separated in geography and...

The full text of this article can be purchased from Informit.