The region represents a portion of a large foredeep (Carpathian Foredeep) that formed during the Miocene epoch in front of the folding Carpathian Mountains. The outer zone of the foredeep has as its foundation the Podolian Platform; the inner zone consists of severely dislocated flysch deposits. The foredeep itself is filled with thick Miocene deposits of clays, argillites, calcareous clays, and sandstones covered by diluvial and alluvial deposits.