We suggest a new explanation for the presence of crustally derived zircons in the upper-mantle rocks of ophiolitic complexes, as an alternative to subduction-related models. Integrated isotopic (U-Pb, Hf, and O isotopes) and trace-element data for zircons from the Tumut ophiolitic complex (southeast Australia) indicate that these grains are related to granitic magmatism and were introduced into...

ten chromite ores from ophiolite complexes in se iran were analyzed mineralogically by xrd, chemically by xrf, and mineral chemistry by epma. the identified paragenesis of silicate minerals of chromite ores with the x-ray diffraction is pronounced differently. it consists of secondary phases formed as serpentine, cr-containing chlorite (kaemmererite), chromic garnet (uarovite) with preserved pa...

the forumad ophiolite in the northwestern part of the sabzevar region has embraced the largedepleted harzburgites and dunitic bodies associated with podiform chromitites. in some deposits, chromitegrains have segregated as nodules. the stretched shape along with high cr2o3 and tio2 contents are thecharacteristics of the nodules. compared to the other tethyan nodular chromites, the forumad nodul...

Subduction initiation processes, such as those evidenced in the Izu-Bonin-Mariana (IBM) forearc crust are a key feature of modern-style plate tectonics. However, evidence for this process Precambrian is limited, due to scarcity ophiolite suites and particular lack typical complete ophiolitic sequences similar observed Phanerozoic ophiolites. Mineral analyses olivine, orthopyroxene, chrome spine...