2026/01/09 by Mahdi Najafi, Jaume Vergés, David Cruset +8 · 1 voice
Earth and Planetary Sciences · #Geological and Geochemical Analysis #Geological and Geophysical Studies Worldwide #Karst Systems and Hydrogeology
paper · doi:10.1016/j.earscirev.2026.105391
openalex publication_date 2026/01/09 · openalex created_date 2026/01/10 · openalex updated_date 2026/07/02
The Semail Ophiolite in Oman has been central to obduction research for over 50 years. Our new study builds on this legacy, introducing 254-km long balanced and restored NE-SW cross-sections that run from the Semail Ophiolite to the Fahud foreland. These sections through Central Oman, resolve geometric inconsistencies, providing a clearer, quantifiable crustal-scale kinematic model from mid-Cretaceous to present-day. Our findings reveal a ~ N030° compressional direction from 15 new localities, reconstruct a 235 km minimum length pre-obduction hyperextended Hawasina Basin, and identify the 16–22-km wide Sumeini slope as a crucial low-angle footwall ramp for allochthonous nappes. We have also pinpointed four main detachment levels shaping the Central Oman Mountains: the Semail Ophiolite and Hawasina basal detachments, the Jabal Akhdar flat-ramp-flat thick-skinned thrust, and the Ara Salt detachment. Through stepwise kinematic reconstructions, we defined three key subduction-driven obduction stages from mid-Cretaceous: 1) Pre-obduction Stage (Albian-Cenomanian boundary to 95.2 Ma) characterized by NE-dipping intra-oceanic subduction and slab rollback; 2) Obduction Stage (~95.2–80 Ma) depicting the Semail Ophiolite and Hawasina nappes obduction over the Oman margin; and 3) Post-obduction Mountain-building Stage since Campanian times. Finally, we have estimated a convergence rate of 22 mm/yr during the Late Cretaceous (95.2 to 85 Ma), accounting for near half of the total convergence between Arabia and Eurasia. This study provides a powerful new framework for understanding obduction and mountain building, serving as a valuable template for investigating regions where later continental collision has obscured evidence of these processes.