The Dead Sea: Earth's nadir and saltiest sea
Q: What is the saltiest sea in the world? --M.Kelvin Harris, Cambridge, England
A: The Dead Sea-devoid of life, except for bacteria, and so salty it quickly kills river fish swept by
floodwaters into its brine-is the saltiest sea on Earth. This land-locked lake gets saltier with
increasing depth. The surface, fed by the River Jordan, is the least saline. Down to about 130 feet
(40 meters), the seawater comprises about 300 grams of salt per kilogram of seawater. That's about
ten times the salinity of the oceans. Below 300 feet, though, the sea has 332 grams of salt per
kilogram of seawater and is saturated. Salt precipitates out and piles up on the bottom of the sea.
[theodora.com, used with permission] Land-locked Dead Sea between Israel and Jordan
The lower waters are so dense with salt they remain permanently on the bottom. The upper waters
date from a few centuries after biblical times to the present.
The name, Dead Sea, goes back at least to the Hellenistic epoch (323 to 30 BC). Sodom and
Gomorrah (cities, according to the Old Testament, destroyed by fire for their wicked ways) maybe lie
under the southern part of the Dead Sea. The Jewish sect that left the biblical manuscripts, known as
the Dead Sea scrolls, took shelter in caves northwest of the Dead Sea.
The Dead Sea wins another superlative: not only the saltiest water but also the lowest point on Earth. Its surface is about 1300 feet (400
meters) below sea level; the lake reaches a depth of 1300 feet below its surface.
Further Surfing:
Map courtesy of www.theodora.com/maps.
USATODAY.com, WonderQuest: Why the seas are salty
http://www.usatoday.com/news/science/wonderquest/2001-09-12-salty-seas.htm
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