Palinspastic maps ('palinspastic' from Greek: 'drawn back') restore deformed rocks to their pre-deformation positions by removing the effects of folding, faulting, and thrusting. This is done by balancing and restoring cross-sections. They are essential for basin analysis and petroleum exploration to understand original depositional geometry. Paleogeographic maps show ancient geography; paleotectonic maps show ancient tectonic settings; paleogeologic maps show pre-unconformity geology.