Tharthar

The Tharthar depression lies between the Tigris and Euphrates in the dry country west of Samarra. A broad natural hollow, it receives the drainage of Wadi Tharthar, which runs south from the hills near Sinjar. Salt-bearing ground and the shallow slopes of the basin distinguish it from the irrigated banks of the great rivers. Rainfall and runoff are seasonal, and much of the surrounding land is open steppe rather than settled river valley.