Tengiz

Tengiz 

(or Dengiz), a bitter lake in the northern part of the Kazakh Melkosopochnik, in the Kazakh SSR.

Lake Tengiz is situated in a tectonic basin. It has an area of 1,590 sq km and is 75 km long, 40 km wide, and up to 8 m deep. The shores are mostly low-lying, and the eastern shore is strongly indented, with several offshore islands. In the northeast there is a shallow bay. The lake is fed mainly by snow. The bottom is even, and in places it is composed of black silt, which is suitable for therapeutic purposes. In some years a substantial portion of the lake dries up. The water contains mirabilite, with a salinity of 3–12.7 parts per thousand (%₀) and, in the bay, 18.2 %₀. The lake freezes in December and opens up in April. The Nura and Kulanutpes rivers empty into Lake Tengiz.