Petrology
Mostafa Delkhah; Habib Biabangard; Hamedreza Soloki
Abstract
Zardkuh igneous complex is located in 35 km Southeast of Iranshahr and is geologically situated flysh zone and the Sistan-suture zone. Rock units in the area are Ophilitic rocks (upper Cretaceous), Eocene flysh and Oligomiocene intrusive and extrusive rocks (Zardkuh igneous complex). Patterns of minor ...
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Zardkuh igneous complex is located in 35 km Southeast of Iranshahr and is geologically situated flysh zone and the Sistan-suture zone. Rock units in the area are Ophilitic rocks (upper Cretaceous), Eocene flysh and Oligomiocene intrusive and extrusive rocks (Zardkuh igneous complex). Patterns of minor and rare earth elements normalized to Primitive mantle and Chonderit show low enrichment to LREE such as La, Ce and Sm than to HREE such as Ho, Yb, Tb and Lu. The dip of digram is soft to HREE and in the extrusive rocks is low increased. . it is thought that the constituent magma of these rocks from the mantle wedge above the subduction plate, which is usually affected by the fluids released from the subducted plate and its elements (including Silica, potassium and sodium) can produce such magma. So these rocks are related to magmatism and subduction Neo-Tehyan oceanic between Lut and Sistan blocks.
Gh Ghadami; M Poosti; F Babai
Abstract
Few More than 5 dacite to andesite volcanic masses with Mio-Pliocene age are exposed to older volcanic rocksat the south and east of the Mozahem volcano, in south-east of Urumieh- Dokhtar magmatic belt, north-east of Shahre-Babak. These rocks show hyaloporphyritic- trachytic texture and consist of pPhenocrysts ...
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Few More than 5 dacite to andesite volcanic masses with Mio-Pliocene age are exposed to older volcanic rocksat the south and east of the Mozahem volcano, in south-east of Urumieh- Dokhtar magmatic belt, north-east of Shahre-Babak. These rocks show hyaloporphyritic- trachytic texture and consist of pPhenocrysts of plagioclase, amphiboles and biotites. Based on geochemical data and multi elements patterns, these rocks are medium to high K calc-alkaline suite and they show LILE and LREE enriched normalized multi-element patterns, and negative Nb, Ti and Ta anomalies. Chondrite normalized REE patterns display a steep decrease from LREE to HREE without any Eu anomaly. They have higher SiO2 and Sr contents and Sr/Y and La/Yb ratios and low MgO, Y and Yb contents than the normal calc-alkaline volcanic rocks. These volcanic rocks are formed in the a subduction zone in an active margin, and showing full complete of HSA(high SiO2 adakites) characteristics. HREE and Y depleted patterns suggest the existence of garnet and amphibole as a residue in the source. The source of these rocks was probably amphibole-eclogite or garnet-amphibolite possibly generated during subduction or slab break of the Neo-Tethyan oceanic slab beneath the Central Iran microplate in Neogene.