"Moist MORB" axial magmatism in the Oman ophiolite: The evidence against a mid-ocean ridge origin

Mid-ocean ridge (MOR) and suprasubduction zone (SSZ) geological events in the Yarlung Zangbo suture zone: Evidence from the mineral record of mantle peridotites

“…Our mineralogical and geochemical data for the Purang mantle rocks are consistent with a two-stage origin for the ophiolite, in which it formed originally at a MOR and was later modified by SSZ processes (Batanova and Sobolev, 2000;Choi et al, 2008;Aldanmaz et al, 2009;Zhou et al, 2005Zhou et al, , 2014Rollinson and Adetunji, 2013;Macleod et al, 2013). Stern and Bloomer (1992) proposed a subduction-initiation model that involved both MORB Pearce et al, 2000), showing the abyssal peridotite field of Dick and Bullen (1984), SSZ peridotites field of Pearce et al (2000) and the olivine-spinel-mantle array (OSMA) and melting trend of Arai (1994).…”

Constraints on the accretion of the gabbroic lower oceanic crust from plagioclase lattice preferred orientation in the Samail ophiolite

“…The geochemistry of lavas in the Samail ophiolite is systematically different from that of lavas from mid-ocean ridges (e.g., Pearce et al, 1981;MacLeod et al, 2013). Gabbroic rocks also differ; evolved Oman gabbros rarely contain abundant orthopyroxene, and commonly contain igneous hornblende (e.g., Pallister and Hopson, 1981), unlike evolved mid-ocean ridge gabbros (e.g., Mevel et al, 1996).…”

Melts of sediments in the mantle wedge of the Oman ophiolite

“…The lava pile consists of three geochemically different groups: the early lavas and sheeted dikes resemble mid-oceanic ridge basalts (Geotimes or V1 lavas) and grade into lavas with typical subduction signatures (Lasail and Alley or V2 lavas), implying that the ophiolite formed above a subducting slab (e.g., Godard et al, 2003;MacLeod et al, 2013;Goodenough et al, 2014). The late V3 lava group is incompatible element enriched and appears to be related to off-axis volcanism.…”