We commend Breton et al. (2004 in GeoArabia, volume 9, issue 2) for their lithospheric-scale presentation and interpretation of the tectonic development of North Oman. It is a signifi cant and welcome advance in the geodynamic understanding of the obduction of the Samail Ophiolite, one of the largest and best preserved ophiolites. We have however, two issues with the models presented in their Figure 8 , but we point out that these are based on data that have only become available since

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... n of the Breton et al. manuscript. These new data require signifi cant changes to parts of their proposed model. They are: (1) the timing of peak eclogite facies metamorphism, and thereby the timing of "intracontinental" subduction. Very recently published Sm-Nd garnet-garnet leachate-whole rock isochron ages of 110 ± 9 Ma (5-point isochron) and 109 ± 13 Ma (3-point isochron) from garnet-bearing eclogites at As Sifah (Gray et al., 2004b) , require that subduction must have been ongoing at least by ~110 Ma. These data restate that peak metamorphism is older than the crystallization age of the Samail Ophiolite, despite recently published Rb/Sr ages of 78 ± 2 Ma (El-Shazly et al., 2001) and a SHRIMP U-Pb zircon age of 79.1 ± 0.3 Ma (Warren et al., 2003). Structural overprinting and metamorphic fabric relationships (see Miller et al., 1999; Gray et al., 2004a) indicate that previously published Rb/Sr ages of 78 Ma (El-Shazly et al, 2001) and 40 Ar/ 39