Tigris–Euphrates river system Tigris–Euphrates river system The Tigris and Euphrates, with their tributaries, form a major river system in Western Asia. From sources originating in eastern Turkey, they flow by/through Syria through Iraq into the Persian Gulf. The system is part of the Palearctic Tigris–Euphrates ecoregion, which includes Iraq and parts of Turkey, Syria, Iran, Saudi Arabia, Kuwait, and Jordan. From their sources and upper courses in the mountains of eastern Anatolia, the rivers descend through valleys and gorges to the uplands of Syria and northern Iraq and then to the alluvial plain of central Iraq. The rivers flow in a south-easterly direction
Bottom water in temperature and salinity, especially compared to wind-driven surface ocean currents. The bottom water of the Arctic Ocean is more isolated, due to the topography of the Arctic Ocean floor and the surrounding Arctic shelves. Bottom water by an estuary of a river discharging into a saline body exhibits peculiar transport of mud. Due to fresh/saline water intermixing by the estuary, a horizontal isohale gradient is created, with lower salinity levels upstream, which generates the upstream flow of the bottom water. Mud particles carried by river begin settling down as the current and turbulence decrease. When the particles nearly reach