In the northern Oman Mountains several major thrust sheets of Tethyan oceanic rocks (Dibba zone) and a 12km+ thick complete ophiolite sequence have been thrust westward onto the depressed Arabian continental margin (Musandam zone) during the Turonian to Campanian (late Cretaceous). Early thrusting was dominantly a downward foreland-propagating sequence as the higher earlier thrust sheets are folded around structurally lower and later culminations. Breached roof thrusts, where imbricate thrusts do not always converge with a major roof thrust but in places actually penetrate up into the overlying duplex, are common at outcrop scale affecting adjacent thrust sheets. Late stage ‘breakback’ or ‘leap-frog’ thrusts cut through the whole pile of duplexes on to previously higher, earlier dulexes. Late thrusting in the Musandam zone affects the deeper, previously autochthonous Permian–Cenomanian shelf carbonate sequence and probably also the pre-Permian basement, thrusting these rocks at least 15 km over previously allochthonous Hawasina rocks. Late stage oblique dorsal culmination collapse along the SE margin of the Musandam mountains has downfaulted Dibba zone rocks up to 2.5 km to the SE along a hinged listric normal fault. Strain is transferred from the NE–SW-trending late Cretaceous Dibba zone to the N–S-striking mid-Tertiary Musandam culmination at a major pivot point or transfer zone SW of the shelf carbonate culmination.

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