Karasor (Kazakh: Қарасор; Russian: Карасор) is a salt lake in the Ekibastuz City Administration, Pavlodar Region, Kazakhstan.

Smaller lake Shandaksor, with the Ekibastuz GRES-2 Power Station rising by its eastern shore, lies 8 kilometers (5.0 mi) to the west of the northwestern corner, and Zhyngyldy, with the Ekibastuz GRES-1 Power Station by its northern shore, lies 17 kilometers (11 mi) to the WSW of the southwestern lakeshore.

[1][2] Large quantities of ash are dumped into lake Karasor by the two neighboring power plants.

The accumulation of dumped ashes in the southern part of the lake forms an island or peninsula with an average diameter of 2.5 kilometers (1.6 mi).

The ashes are collected by people of the neighboring villages in order to sell them to be recycled for the industrial production of aluminosilicate microparticles.