Excerpt from a very interesting article
In northeastern Ethiopia one of the earth’s driest deserts is making way for a new ocean. This region of the African continent, known to geologists as the Afar Depression, is pulling apart in two directions—a process that is gradually thinning the earth’s rocky outer skin. The continental crust under Afar is a mere 20 kilometers from top to bottom, less than half its original thickness, and parts of the area are over 100 meters below sea level. Low hills to the east are all that stops the Red Sea from encroaching.
Key concepts:
- Africa is splitting apart at the seams—literally. From the southern tip of the Red Sea southward through Eritrea, Ethiopia, Kenya, Tanzania and Mozambique, the continent is coming unstitched along a zone called the East African Rift.
- Like a shirtsleeve tearing under a bulging bicep, the earth’s crust rips apart as molten rock from deep down pushes up on the solid surface and stretches it thin—sometimes to its breaking point. Each new slit widens as lava fills the gap from below.
- This spectacular geologic unraveling, already under way for millions of years, will be complete when saltwater from the Red Sea floods the massive gash. Ten million years from now the entire rift may be submerged.
—The Editors
I am a long-time reader and fan of Scientific American. In fact, BW (Before WWW).
I now use Scientific American Digital. The biggest advantage of digital versions of ANY printed media, is the ability to get just the articles you are interested in.
In the case of Scientific American Digital, for my yearly subscription, I get downloaded PDF of:
- Versions of older (Archived) individual articles (or entire magazine) with no extra charge (this is how I got this article)
- Versions of Special Articles for a small additional fee
- Current month's articles or magazine for an additional fee (before archive)
- Special Digital (only) Articles and magazines with no extra charge
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