Caspian Depression
The Dnieper-Donets Rift or Pripyat-Dnieper-Donets Rift (also referred as a "paleorift" and "aulacogen") is an east-west running rift in the Sarmatian Craton that developed and was most active in the Paleozoic. The rift extends from the Caspian Depression in Russia to northern Ukraine passing by the Donbas region. The rift separates the Voronezh Massif in the north from the Ukrainian Shield in south.