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 Late Neoproterozoic (548-579 million years ago) metamorphic - igneous Shotor Kuh complex is cropped out in SE Shahrood, consist of a various range of rocks including metabasite, metapelite, metagraywake, metapsammite and metacarbonate. Metapelites include phyllite to gnessis and migmatite. Metamorphism intensity in the highest degree, progressed to anatexy and formation of granitic melts. Thermobarometery results  of metapelites can be correlated by the greenschist to amphibolite facies (T= 457-641 °C and P= 6-13 Kbar). According to the results, The primarily sedimentary sequences (prtolith of Shotor-Koh metamorphic - igneous complex) formed during intracontinental extensional- rifting regim in the sea- ocean basins. These sea- ocean basins, have been closed during Cadomian orogeny event, metamorphosed and consist of tectonic melange or accretionary prisms which thrusted on the neghibours continental crust.

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Dioritic plutons and pinkish alkali-feldspar granitic dikes of Kalateh area (northwest of Khur city) intruded in Neoproterozoic basemental of Jandagh- Arousan complex. Field observations, petrography and geochemical studies indicate that these intrusive rocks have I-type nature and belong to medium-high K calc-alkaline granitiods and also have genetically relationship with each other. Their parental magmas produced by partial melting of metasomatized mantle wedge which was located above the subducted Neotethyan oceanic slab. The mentioned magmas generated in an intracontinental back arc extensional setting in relation to the subduction of oceanic Neotethys slab. U-Pb dating results on separated zircon from dioritic and alkali-feldspar granitic rocks indicated 213.9 ± 1.6 to 221.16 ± 1.6 Ma interval age (corresponding to Late Triassic). These igneous rocks are indications of magmatic manifestations of Early Cimmerian Orogeny.

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Late Neoproterozoic metamorphic – igneous rocks of the Shotor Kuh complex is located in the northern edge of the Central Iran structural zone. This complex crosscut by several Middle Jurassic diabasic dikes. Plagioclase, pyroxene and biotite are the essential rock-forming minerals of these dikes. Plagioclases have mostly andesine composition (An_31-49). Pyroxenes have following compositions: En_30-45Fs_29-42Wo_25-29. Biotites with X_Fe = 0.49-0.53 and X_Mg= 0.46 - 0.5 are mostly Mg rich biotites. Temperatures and pressures obtained from clinopyroxene thermobarometry are in the range of 1200-1100°C and 10-2 kbar respectively. By attention to the results of chemichal composition of these minerals, magma forming of these dikes has calc-alkaline nature and during their crystallization oxygen fugacity has been low. The mentioned dikes generated in a tectonic setting accommodate to intracontinental extensional regime such as a back arc basin (subduction of Neo-Tethys oceanic lithosphere beneath the Central Iran zone).

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At the base of Shemshak Formation in the south Azadshahr area, some igneous mafic rocks are discovered recently  as olivine gabbro bodies and pegmatoid alkali-diorite dikes. Rock-forming minerals of olivine gabbro includes olivine, clinopyroxene and plagioclase, alkali-diorites are composed of large amphiboles and plagioclase. Major and trace elements characteristics of these rocks indicate they have alkaline nature and derived from OIB-like mantle source. Mineral chemistry of olivines and plagioclases in olivine gabbros determined as chrysolite and labradorite, respectively. Clinopyroxenes in olivine gabbros have diopsidic to augitic composition  and alkaline (Non-orogenic) affinity, and they formed in 2-11 Kbar, 1200-1250˚C and high oxygene fugasity conditions. Amphiboles in alkai-diorites are calcic and characterized with kaersutite to magnesiohastingsite in composition, igneous nature and derived from mantle sources. Their crystallization temperature and pressure are 950˚C and 600-750 MPa (equivalent 6-7/5 Kbar). Plagioclases in alkali-diorites are albite.