Cephalopod limestones of Middle Permian (Middle Guadalupian, Wordian Stage) age occur at the base of the Hawasina
nappes in the Oman Mountains.  They overlie mafic volcanic rocks, are a few meters thick, are interbedded locally with
 reef-derived gravity flow deposits.  The cephalopod limestones are interpreted as a condensed sequence caused by a
regional transgression on the Arabian platform.  The ammonoid fauna is remarkably similar to that of the western
Mediterranean and Timor, suggesting an unrestricted faunal exchange in a Permian seaway along the northern margin of
Gondwana where pelagic sediments were being deposited.  Due to the uncertain provenance of the Cimmerian
microcontinents, the width of this seaway must remain speculative.