List of Articles Sistan Suture Zone

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  1 - Constraints on the Petrogenesis of Nosrat-Abad Ophiolite Extrusives, SE Iran
  Mohammad Elyas Moslempour Morteza Khalatbari-Jafari Rahim Dabiri Sara Shahdadi
  Nosrat-Abad ophiolitic extrusive sequence, located in the Sistan Suture Zone, in south eastern Iran. The extrusive sequence, contains pillow lava, sheet flow and related volcanic-clastic breccias which have undergone low-grade metamorphism. This association shows calc a More

  Nosrat-Abad ophiolitic extrusive sequence, located in the Sistan Suture Zone, in south eastern Iran. The extrusive sequence, contains pillow lava, sheet flow and related volcanic-clastic breccias which have undergone low-grade metamorphism. This association shows calc alkaline to tholeiitic affinities. Interpretation of the geochemical data and behavior of the elements in different diagrams reveals two distinct domains in the Nosrat-abad ophiolitic extrusive sequence. The sheet flows are depleted in HFSE similar to those of SSZ. However, the enrichment of the pillow lavas in LILE could be attributed to an enriched mantle source or melting of metasomatized sediments above the subducted slab. It appears that two subduction components (fluids-melt), caused the diversity seen in the chemical composition of the study rocks. The MORB to subduction chemical characteristics of the Nosrat-Abad ophiolitic extrusive sequence could be explained by a shift in the tectonic settings from the mid-ocean ridge to the marginal basin in Sistan during the Late Cretaceous period. Manuscript profile
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  2 - Petrogenetic Evolution of Plio-Quaternary Mafic Lavas in Nehbandan (East Iran)
  Mohammad Reza Ghasempour Javad Mehdipour Ghazi Habib Biabangard Rahim Dabiri
  Both the Sistan Suture Zone of eastern Iran and the Nehbandan Fault contain Plio-Quaternary Nehbandan mafic lavas. Positive anomalies in the large ion lithophile elements (LILE) and negative anomalies in Nb (niobium) exist in these mafic lavas. This indicates the occurr More

  Both the Sistan Suture Zone of eastern Iran and the Nehbandan Fault contain Plio-Quaternary Nehbandan mafic lavas. Positive anomalies in the large ion lithophile elements (LILE) and negative anomalies in Nb (niobium) exist in these mafic lavas. This indicates the occurrence of subduction magmatism and post-collision volcanism. Petrologic and geochemical analyses distinguished two groups of lava. Group I contains alkaline basalts with a slight depletion in Nb while Group II contains sub-alkaline basaltic andesite to andesite with a sharp depletion in Nb. Geochemical studies show that fractional crystallization and crustal contamination played an important part in the evolution of the Nehbandan lavas. Group II, however, was more greatly affected than Group I. Geochemical studies also indicate that these lavas may have been generated due to a low degree of partial melting (<5%) of garnet and the spinel-bearing lithospheric mantle; Group I shows more garnet than spinel while Group II shows the opposite. The research carried out for this paper suggests that the Plio-Quaternary Nehbandan mafic lavas were formed as a result of slab detachment or delamination and domination, an extensional condition correlated to the thinning of the crust and lithosphere in the Sistan Collision Zone. These conditions are concomitant with localized stretching along the Nehbandan Fault and the upwelling of magma forming mafic lavas. Manuscript profile