The Musandam peninsula (Sultanate of Oman) is a vast outcrop of carbonate rocks of Permian to Middle Cretaceous age. The facies of these formations relates them without doubt to the contemporaneous formations of the Arabian platform and there is a good analogy with the formations encountered in the wells drilled in the Persian Gulf west of the Musandam outcrops. After the deposition of these platform formations, several tectonic events deepb affected this area, and led to the present configuration: at the end qf the Middle Cretaceous, a wide area emerged on the E edge of the Arabian platform. whereas on the W side of the Peninsula important halokinetic movements of the structures of thePersian Gulf persisted. Following that tectonic event, the sedimentary domain of the platform withdrew towards the Arabian shield during the Upper Cretaceous, whereas the orogenic activity spread out into the oceanic domain. The Musandam peninsula was located between those two domnins, in a sedimentary basin which successively received first the turbidites of'the Muti Formation (Coniacian ‐ Santonian), mainly produced by the erosion of the Middle Cretaceous emerged area, and then the Hawasina nappes, mainly formed by abyssal sediments of earlier Mesozoic age. Itis not firmly established whether the Semail nappe of the ophiolitic complex was emplaced over the Musandam as it was over the greater part of the Oman mountains. During and after the setting of the nappes, E‐W compression caused the series of overthrusts, creating in the Musandam area a ridge edged on the W by a subsidmr foredeep which received materials from the ridge, and on the E by an oceanic zone in which the sedimentation was far more reduced. The same pattern continued until the end of the Lower Miocene, when a very important compressive movement from E to W gave their present shape to most structures. During the Upper Miocene, vertical movements of compensation took place and continued to thepresent time over Musandam, while on the E flankof the Peninsula, in the subsiding Gu(fof Oman, sedimentation became very important.