Field data in combination with interpretation of old seismic lines across the Pusht-e Kuh arc and northwest Dezful embayment in the Zagros fold belt allow the investigation of the geometry of folding at different structural levels. Folds in the Pusht-e Kuh arc are exposed along the upper part of the 7-km (4.34-mi)-thick Competent Group level, which is folded between the main detachment at or near the base of the cover sequence (lower Mobile Group) and the Gachsaran evaporites (upper Mobile Group). Intermediate detachment levels (Triassic Dashtak, middle Cretaceous Garau and Kazhdumi, Paleocene Amiran, and middle Miocene Kalhur formations) within the Competent Group control the geometry of anticlines at surface as well as their variations with depth. The Kabir Kuh anticline is the largest and highest anticline in the Pusht-e Kuh arc and has been selected to construct a geometrical model to explore the variations of folding style with depth. Results from this anticline constituted a backbone for both a regional study to link the mechanical stratigraphy to the structure and to build up a conceptual model for folding that may apply to the Pusht-e Kuh arc as well as to the Dezful embayment tectonic domains. The Kabir Kuh anticline in its central part displays box fold geometry, characterized by a wide and rounded crestal domain, which is slightly tilted to the southwest. This geometry developed above an intermediate detachment at the level of 1.3-km (0.81-mi)-thick Triassic Dashtak Copyright © 2011 by The American Association of Petroleum Geologists.