Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published 2014 | public
Journal Article

The Ayyubid Orogen: An Ophiolite Obduction-Driven Orogen in the Late Cretaceous of the Neo-Tethyan South Margin

Abstract

A minimum 5000-km long obduction-driven orogeny of medial to late Cretaceous age is located between Cyrenaica in eastern Libya and Oman. It is herein called the Ayyubid Orogen after the Ayyubid Empire that covered much of its territory. The Ayyubid orogen is distinct from other Alpide orogens and has two main parts: a western, mainly germanotype belt and an eastern mainly alpinotype belt. The germanotype belt formed largely as a result of an aborted obduction, whereas the alpinotype part formed as a result of successful and large-scale obduction events that choked a nascent subduction zone. The mainly germanotype part coincides with Erich Krenkel's Syrian Arc (Syrischer Bogen) and the alpinotype part with Ricou's Peri-Arabian Ophiolitic Crescent (Croissant Ophiolitique péri-Arabe). These belts formed as a consequence of the interaction of one of the now-vanished Tethyan plates and Afro-Arabia. The Africa-Eurasia relative motion has influenced the orogen's evolution, but was not the main causative agent. Similar large and complex obduction-driven orogens similar to the Ayyubids may exist along the Ordovician Newfoundland/Scotland margin of the Caledonides and along the Ordovician European margin of the Uralides.

Additional Information

© 2014 GAC/AGC®. Received July 2013; Accepted as revised January 2014. We are extremely pleased and honoured to contribute this paper in memory of a great geologist, Professor Harold ('Hank') Williams, a master of ophiolite geology, among other subjects. For Şengör, the pleasure and honour are related to a long friendship with Professor Williams. Williams was among his earliest field instructors. When Şengör was only a second-year student, his teacher John F. Dewey sent him to work under Williams and W.S.F. Kidd for a month in Newfoundland. That was his first encounter with ophiolites in the field. That initial acquaintance turned into a life-long friendship, during which he continued to learn from Williams. We thank Jim Hibbard, who was the other student with Şengör during that memorable field work in Newfoundland, for inviting us to contribute to the Williams' memorial volume. Şengör's friends in Libya, especially Emin Yanılmaz and Ali El-Arnauti, who took him around in Cyrenaica, showed him the critical outcrops and provided him with a massive amount of literature, probably would have been co-authors in this paper, had the unfortunate events that befell both Libya and Syria not led to his losing their tracks. We heard that Emin Yanılmaz safely left Syria to return to Turkey, but we have not been able to get any news of Ali El-Arnauti. We can only hope that he managed to survive safely the destruction of his country. Professor Hubert Whitechurch kindly supplied us with a pre-print of his important new paper on the Kermanshah ophiolites in Iran and Professor Leigh H. Royden discussed with us her work with Oliver Jagoutz in the Himalayan Neo-Tethys that much encouraged us in our interpretations. She was also helpful in evaluating the Libyan gravity anomalies. Professor Ali Polat helped with literature research in Canada. We thank Professors Brian P. Wernicke , B. Clark Burchfiel and an anonymous reviewer for a critical reading of an earlier draft of this paper. Jim Hibbard, the guest editor of Hank's volume and Brendan Murphy, the editor-in-chief of Geoscience Canada also made us work hard to make our presentation clearer. We thank Cindy Murphy for her great assistance during the final production of the paper.

Additional details

Created:
August 19, 2023
Modified:
October 26, 2023