Caspian Sea
The Caspian Sea, like the Black Sea, Namak Lake, and Lake Urmia, is a remnant of the ancient Paratethys Sea. It became landlocked about 5.5 million years ago due to tectonic uplift and a fall in sea level. During warm and dry climatic periods, the landlocked sea almost dried up, depositing evaporitic sediments like halite that were covered by wind-blown deposits and were sealed off as an evaporite sink when cool, wet climates refilled the basin. (Comparable evaporite beds underlie the Mediterranean.) Due to the current inflow of fresh water, the Caspian Sea is a freshwater lake in its northern portions, and is most saline on the Iranian shore, where the catchment basin contributes little flow. Currently, the mean salinity of the Caspian is one third that of Earth's oceans. The Garabogazköl embayment, which dried up when water flow from the main body of the Caspian was blocked in the 1980s but has since been restored, routinely exceeds oceanic salinity by a factor of 10.
History of Central Asia
The economic performance of the region since independence has been mixed. It contains some of the largest reserves of natural resources in the world, but there are important difficulties in transporting them. Since it lies farther from the ocean than anywhere else in the world, and its southern borders lay closed for decades, the main trade routes and pipelines run through Russia. As a result, Russia still exerts more influence over the region than in any other former Soviet republics. Nevertheless, the rising energy importance of the Caspian Sea entails a great involvement in the region by the US. The former Soviet republics of the Caucasus now have their own US Special Envoy and inter-agency working groups. Former US Secretary of Energy Bill Richardson had claimed that "the Caspian region will hopefully save us [the US] from total dependence on Middle East oil".