Situated on the heart of the Great Syrian-African rift valley that stretches throughout Israel and beyond, the Dead Sea is the lowest point on the earth, 1, feet below sea level and is flanked by the Judean Mountains on the west, the Hashemite Kingdom of Jordan and the Mountains of Moab on the east, the Jordan Valley and Sea of Galilee to the north and the Negev Desert as well as the Red Sea to the south.
The human history of the Dead Sea goes all the way back to remote antiquity. Just north of the Dead Sea is Jericho, the oldest continually occupied town in the world. Aristotle wrote about the remarkable waters. Roth, Burkhardt, and others, including the Survey made by the officers of the Royal Engineer. It is curious however that the remarkable physical phenomenon which renders the Holy Land unique among all countries regarded in its physical aspect was not discovered till the year —37, when Heinrich Von Schubert and Prof.
Roth determined by barometric observations that the surface of the Dead Sea lies no less than feet below the level of the Mediterranean, a fact not suspected by previous observers.
It is the deep depression of the Jordan Valley, deeper by far than any river valley elsewhere, which is the key to the physical history of the whole country; and in endeavouring to trace out its origin I shall reproduce in as general a manner as I can the successive phases through which the region bordering the Meditsrranean, and extending eastwards towards the Euphrates and southwards to the Dead Sea, has passed. The fundamental basis of the geological formation of Palestine is the gneissic granite, of Archsean age and metamorphic origin, which rises into the mountains of Idumea, and is the rock from which the huge monoliths of Egypt have been hewn, snob as Cleopatra's Needle' the obelisk of Luxor, and the ealumns which adorn the Piazza of Venice.
The first appearance of Palestine and the adjoining districts as a land snrface dates from the succeeding Miocene period, when the bed of the sea was npraised into dry land, and at the same period a great fissure corresponding with the line of the Jordan valley svas prodnced. Along this fissure, which has been traced frono the Lebanon sonthwards towards the Gulf of Akaba —the strata on the eastern or Moabite side have been relatively elevated those on the western relatively depressed;—so that the strata on the opposite sides of the Jordan valley and the Dead Sea do not correspond with each other.
This great fissure is the key to the physical formation of the whole region, because it gave origin to a river which once flowed dosvn from the mountains of Lebanon—southwards through the Gorge of Arabah discovered by Bnrkhardt —into the Red Sea in a remarkably straight line rnnning north and sonth for a distance of over miles.
This is now the Jordan. The depression of the valley continuing through the succeeding Pliocene epoch, the district of the Ghor and the Jordan valley was conveyed into a lake, which Prof. Hull considered ultimately extended from the southern end of the Dead Sea, north. This lake would then have had a length of miles and an average breadth of ten miles.
Others are attracted by nearby canyons carved over millennia by spring rains, offering hikers a taste of the desert.
Even the Romans took advantage of the forbidding environment to build an almost-impregnable fortress that visitors can still explore today. The African Plate rotates counterclockwise while the Arabian Plate moves roughly northward. As they move apart, faults form in the graben and pieces of crust sink into the mantle.
About 3 million years ago, water filled the graben, forming the Dead Sea, which was then part of a long bay of the Mediterranean Sea. A million years later, tectonic activity lifted the land to the west, isolating the Dead Sea from the Mediterranean.
As the sea receded from its highest levels, it left behind large salt formations. Two of the largest are the Lisan Peninsula and Mount Sodom, visible along the southern and southwestern shores of the sea, respectively.
The Dead Sea is one of the saltiest bodies of water in the world. Nothing flows out. This hydrological scenario helps explain why the Dead Sea is so salty. Because there is no outlet, the minerals that the Jordan River brings in become trapped in the sea.
Extremely low rainfall less than 10 centimeters per year on average and high evaporation rates in the desert environment compound that effect and give the sea a salt concentration a little higher than 30 percent — making it roughly 10 times saltier than the oceans.
This salinity is high enough to kill any fish that accidentally make their way into the Dead Sea, but the name is technically a misnomer: Algae and some salt-loving bacteria are known to thrive here.
Throughout history, the water levels in the Dead Sea have experienced a number of dramatic rises and falls due to seismic activity. But in recent years, human activity has led to a big drop. Increased use of the Jordan River for irrigation and drinking water has caused water levels to fall 22 meters since , and now they continue to drop about one meter each year.
The Jordanian government has discussed diverting some water from the Red Sea as a potential fix. Several smaller streams also enter the sea, chiefly from the east.
The lake has no outlet, and the heavy inflow of fresh water is carried off solely by evaporation, which is rapid in the hot desert climate. Due to large-scale projects by Israel and Jordan to divert water from the Jordan River for irrigation and other water needs, the surface of the Dead Sea has been dropping dangerously for at least the past 50 years.
Environmental groups, led by Friends of the Earth, launched a "Let the Dead Sea Live" campaign in to preserve the lake and its unique environmental qualities. In September Israel and Jordan agreed to construct a km pipeline that would link the Dead Sea with the Gulf of Aqaba, to slow down the process of evaporation of the lake's waters. If the shrinkage is allowed to continue, it is likely that the Dead Sea might disappear altogether by
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