graben A depressed block of land bordered by parallel faults. A graben is the result of a block of land being downthrown producing a valley with a distinct scarp on each side. Grabens often occur side-by-side with horsts. Horst and graben structures are indicative of tensional forces and crustal stretching. ENVO ENVO:00000290 FTT:682 SWEETRealm:FaultZone Wikipedia:Graben fault zone depression