| Abstract: | A geomorphic field survey conducted in the late 1960's by the Institute of Geography (Moscow) suggests the existence of only one geomorphic level (Level III) that can be traced all the way through the Turgay trough from the Irtysh River drainage basin to the Aral Sea depression. However, contrary to general assumption, geomorphic analysis does not confirm the view that the Turgay trough served for a throughflow of water between the two drainage basins during the Pleistocene. An analysis of the geomorphic levels in the trough suggests that water in the northern segment of the trough drained toward the north and in the southern segment toward the south, with a middle segment occupied by a system of lakes, still evident to this day. However, the absence of a throughflow in the past does not rule out the use of the trough for the proposed southward diversion of Siberian water. It is suggested that the level of water on the Siberian slope be raised to the elevation of the divide (about 125 meters above sea level) so that the water could then follow the natural slope of the Level III surface toward the south. |
