STUDYING the seabed does not always mean penetrating the sea itself, even if that penetration is done using sound waves rather than submarines (see article). There are a few places where what a geologist would call the ocean floor is actually dry land. One such is the Danakil depression, which lies near the northern vertex of the Afar Triangle, a rift valley stretching from the Dallol volcano in Ethiopia past the salt plains of Lake Assal, in Djibouti, to the north-west tip of Somalia, and then inland to Awash. Millions of years ago, the Danakil was indeed covered by the sea—in its case, the Red Sea. But volcanic eruptions formed barriers of lava that isolated it from the ocean. What water remained evaporated in the intense heat, leaving brine lakes and saline flats. These are mined, and the resulting slabs of salt exported by camel, by nomadic Afars who are the nearest thing the depression has to permanent inhabitants.
Dallol, appropriately, means disintegration in Afar....Continue reading
Source: Science and technology http://ift.tt/2ezooaH
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