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Map shows the location of Late Neoproterozoic granitoid rocks in Iran 1-Bornaward; 2-Saghand; 3-Khār Turan, Band-e Hezar Chāh, Torud; 4-Lahijan granite; 5-Khorram Darreh; 6-Sarve Jahan; 7-Doran; 8-Mahneshan; 9-Moghanlou; 10-Bubaktan, Sheikh Chupan; 11-Mouteh.
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The study area (Bornaward granite) is located in northeast of Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city. Taknar zone is an exotic block, bordered by two major faults, Great Kavir fault (Drouneh) to the south and Rivash fault in the north. A complex of granite, granodiorite, monzonite and diorite crop out at the center...
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Whole rock major and trace element geochemistry together with zircon U-Pb ages and Sr-Nd isotope compositions for the Middle Eocene intrusive rocks in the Haji Abad region are presented. The granitoid hosts, including granodiorite and diorite, yielded zircon U-Pb ages with a weighted mean value of 40.0±0.7 Ma for the granodiorite phase. Mafic micro...
Rodríguez et al., (2015) propose the name Granito de Bruselas for a pluton that was mapped near the locality of Bruselas, from which it takes its name, southwest of the Pitalito city. In this catalog, we present the petrographic, geochemical and geochronological features of this unit. The pluton has an outcrop area of about 1 km2 in a North – South...
Citations
... Data for detrital zircons of Iran are from this study and Etemad-Saeed et al., 2016;Honarmand et al., 2016). Data for zircons from Cadomian magmatic rocks in Iran are from: (Ramezani and Tucker, 2003;Bagheri and Stampfli, 2008;Hassanzadeh et al., 2008;Azizi et al., 2011;Karimpour et al., 2011;Rahmati-Ilkhchi et al., 2011;Jamshidi Badr et al., 2013;Nutman et al., 2013;Balaghi Einalou et al., 2014;Bagherzadeh et al., 2015;Faramarzi et al., 2015;Hosseini et al., 2015;Moghadam et al., 2015;Rossetti et al., 2015;Shafaii Moghadam et al., 2015;Shakerardakani et al., 2015;Moghadam et al., 2016;Chiu et al., 2017;Moghadam et al., 2017;Shafaii Moghadam et al., 2017;Shahzeidi et al., 2017;Honarmand et al., 2018;Shabanian et al., 2018;Veiskarami et al., 2019;Asadi Sarshar et al., 2020;Sepidbar et al., 2020;Shafaii Moghadam et al., 2020). ...
Early Paleozoic sandstones deposited along the northern margin of Gondwana are commonly interpreted to represent a vast, well-mixed, and far-travelled blanket of sand sourced from Neoproterozoic orogenic belts in the interior of the landmass. However, the broadly similar timing of magmatism recorded in the interior orogens of Gondwana has hindered previous attempts to identify specific sediment source regions through UPb dating of detrital zircons. Here, we achieve a more refined view of the source-to-sink relationships across the early Paleozoic northern margin of Gondwana by integrating UPb dating and trace element analysis of detrital rutile with UPb dating and Hf isotopic analysis of detrital zircon. We focus on the early Cambrian Lalun Formation, in the Alborz block of Iran, which is one of the most distal exposures of the North Gondwanan sand sheet. The detrital zircon provenance of the Lalun Formation is dominated by Neoproterozoic ages (74%), with fewer pre-Neoproterozoic (22%), and rare early Cambrian (4%) age fractions. Neoproterozoic detrital zircons have variable ɛHf(t) values (−33 to +14), with a predominance of positive values (> 70%), whereas the pre-Neoproterozoic zircons define an approximately linear ɛHf(t)-time array initiating at ɛHf(t) = +7 at ∼2500 Ma and evolving to −15 by ∼1500 Ma. Detrital rutile ages from the Lalun Formation are mostly Cryogenian, with rare pre-Neoproterozoic grains. Calculated Zr-in-rutile temperatures and CrNb compositions imply that most of the detrital rutile was sourced from amphibolite facies metapelites. Comparing our new detrital zircon ɛHf(t) data with an extensive compilation of ɛHf(t) data from magmatic and metamorphic rocks in the East African Orogen demonstrate that the Arabian-Nubian Shield is a more suitable source for the Lalun Formation than more distal portions of the orogen (e.g., Mozambique Belt). The eastern part the Arabian-Nubian Shield also provides a suitable source for the abundant Cryogenian detrital rutile ages in the Lalun Formation. This more proximal source for the Lalun Formation reveals a complicated pattern of sediment dispersal across the northern margin of Gondwana and challenges the notion of a well-mixed, far-travelled sand sheet.
... During the last decades, based on zircon U-Pb geochronologiyl (LA-ICP-MS and TIMS methods), the Cadomian age has been shown for basement rocks in Iran (excluding the Kope Dagh Mountains in the northeast of Iran), for example in the west (Golpayegan: Hassanzadeh et al. 2008; the North of Shahrekord: Badr et al. 2018;Azna: Shabanian et al. 2018), northwest (Khoy-Salmas: Azizi et al. 2011;Zanjan-Takab: Hassanzadeh et al. 2008;Honarmand et al. 2018;Mishu: Shahzeidi et al. 2017;southwestern Saqqez: Daneshvar et al. 2019), northeast (Torud-Biarjmand: Moghadam et al. 2016; Bornaward in Taknar zone: Karimpour et al. 2011;Bagherzadeh et al. 2015), north (Lahijan granites : Lam 2002;Guest et al. 2006;Hassanzadeh et al. 2008), and central Iran (Saghand: Ramezani and Tucker 2003; Kuh-e-Sarhangi: Rossetti et al. 2015) (see. Figure 1). ...
The studied granitic gneiss bodies of the Golpayegan metamorphic complex, located in the central
part of the Sanandaj Sirjan Zone (SaSZ), in western Iran. Zircon U-Pb dating of two samples shows
that the crystallization of the protolith occurred at 557 ± 12 Ma in the Late Neoproterozoic
(Ediacaran), broadly coeval to the Neoproterozoic-Early Palaeozoic basement in other parts of
Iran. Geochemically, the protolith of the gneisses probably corresponds to differentiated I-type
granites with subalkaline affinities in composition. The ratios of Y/Nb >1.2 reveal an affinity to
Cordilleran I-type granites for the granitic gneisses. The high Th/U ratios (2.8 to 9), low Eu/Eu* (0.13
to 0.73), with, low contents of FeO (0.55 to 1.72 wt.%), MgO (0.07 to 0.53 wt.%) and MnO (0.01 to
0.04 wt.%) and the high 87Sr/86Sr(i) ratios (0.70693 to 0.73557), negative ƐNd(t) values (−4.4 to −1.7)
and Nd model ages (TDM2 = 1.35 to 1.56 Ga) suggest that the protolith may have been derived from
partial melting of a pre-existing felsic crustal source (most likely differentiated granitoids). The new
results reveal that the granitic source magma has been evolved in an active continental margin
tectonic regime during the southward subduction of the Proto-Tethys ocean beneath the northern
margin of Gondwana, like other coeval fragments dispersed in the entire Cadomian active
continental margins. Also, the Cadomian crust widely extended in western Iran and it confirms
these rocks have some clear affinity with Cadomian crust in the world.
... During the last decades, based on zircon U-Pb geochronologiyl (LA-ICP-MS and TIMS methods), the Cadomian age has been shown for basement rocks in Iran (excluding the Kope Dagh Mountains in the northeast of Iran), for example in the west (Golpayegan: Hassanzadeh et al. 2008; the North of Shahrekord: Badr et al. 2018;Azna: Shabanian et al. 2018), northwest (Khoy-Salmas: Azizi et al. 2011;Zanjan-Takab: Hassanzadeh et al. 2008;Honarmand et al. 2018;Mishu: Shahzeidi et al. 2017;southwestern Saqqez: Daneshvar et al. 2019), northeast (Torud-Biarjmand: Moghadam et al. 2016; Bornaward in Taknar zone: Karimpour et al. 2011;Bagherzadeh et al. 2015), north (Lahijan granites : Lam 2002;Guest et al. 2006;Hassanzadeh et al. 2008), and central Iran (Saghand: Ramezani and Tucker 2003; Kuh-e-Sarhangi: Rossetti et al. 2015) (see. Figure 1). ...
The studied granitic gneiss bodies of the Golpayegan metamorphic complex, located in the central part of the Sanandaj Sirjan Zone (SaSZ), in western Iran. Zircon U-Pb dating of two samples shows that the crystallization of the protolith occurred at 557 ± 12 Ma in the Late Neoproterozoic (Ediacaran), broadly coeval to the Neoproterozoic-Early Palaeozoic basement in other parts of Iran. Geochemically, the protolith of the gneisses probably corresponds to differentiated I-type granites with subalkaline affinities in composition. The ratios of Y/Nb >1.2 reveal an affinity to Cordilleran I-type granites for the granitic gneisses. The high Th/U ratios (2.8 to 9), low Eu/Eu* (0.13 to 0.73), with, low contents of FeO (0.55 to 1.72 wt.%), MgO (0.07 to 0.53 wt.%) and MnO (0.01 to 0.04 wt.%) and the high 87 Sr/ 86 Sr (i) ratios (0.70693 to 0.73557), negative ƐNd (t) values (−4.4 to −1.7) and Nd model ages (T DM2 = 1.35 to 1.56 Ga) suggest that the protolith may have been derived from partial melting of a pre-existing felsic crustal source (most likely differentiated granitoids). The new results reveal that the granitic source magma has been evolved in an active continental margin tectonic regime during the southward subduction of the Proto-Tethys ocean beneath the northern margin of Gondwana, like other coeval fragments dispersed in the entire Cadomian active continental margins. Also, the Cadomian crust widely extended in western Iran and it confirms these rocks have some clear affinity with Cadomian crust in the world.
... The Precambrian basement is composed of metamorphic rocks such as phyllites, micaschists, quartzites and granitoids, overlain by a nonmetamorphic succession of about 10 km thickness, ranging in age from late Neoproterozoic to Quaternary (e.g. Stöcklin et al., 1964;Hassanzadeh et al., 2008;Karimpour et al., 2011). Cenozoic magmatic rocks (e.g., Doran granite, 2.8 Ma, TIMS U-Pb zircon age) have also been reported (e.g., Hassanzadeh et al., 2008). ...
The tectonic evolution of Iran during the late Neoproterozoic and early Paleozoic is usually expressed in two models including passive (conventional) and active (alternative) margin tectonic models. The passive margin model proposes rifting of peri-Gondwanan terranes and strike-slip tectonics in a non-magmatic setting while the active margin model suggests the existence of a subduction zone and the formation of a continental arc (known as “Cadomian” arc) along the northern Gondwana margin. The Ediacaran siliciclastic Bayandor Formation from the Soltanieh Mountains in western Alborz records the geological history of Iran during the late Neoproterozoic through its provenance, as aims of our studies, which allows palaeoweathering and tectonic setting reconstructions. Thin-section petrographic analysis of the Bayandor Formation sandstones reveal that the feldspar-rich sandstones including minor values of chert rock fragments have characteristics of both active continental margin settings and recycled orogen provenances. The chemical index of alteration (CIA) indicates a moderate degree of chemical weathering in the source area. Most of the Bayandor Formation sandstones were derived from a dissected arc and a minor number of the samples seem to be derived from a basement uplift and recycled orogen provenance. Geochemical discrimination diagrams using major and trace elements indicate both active continental margin and island arc tectonic settings for the Bayandor Formation sandstones. The results indicate that it is more likely that deposition of this formation took place along an active continental margin and the Cadomian basement of NW Iran comprises a series of metagranites and metamorphic rocks and may have contributed some sediment to the localized Neoproterozoic–Cambrian basins. Other sources were likely located in the basement provinces particularly the Arabian–Nubian Shield that is consistent with the results of this study.
... The Kashmar-Taknar Zone contains two well-known complexes containing Cadomian magmatic rocks, the Taknar complex, and the Bornaward Granitoid Complex (BGC). A detailed geochronological and geochemical analysis of the Taknar complex revealed a Neoproterozoic magmatic flare-up along the northern margin of Gondwanaland (Karimpour et al. 2011;Monazzami Bagherzadeh et al. 2015). The magmatic rocks of the Taknar complex range from monzonite to granodiorite and granite ( Figure 6) with sub alkaline and metaluminous to peraluminous character ( Figure 8(a,b)). ...
... Results obtained from zircon U-Pb dating of the BGC rocks suggest an age of 540 to 550 Ma (Monazzami Bagherzadeh et al. 2015), whereas the dating of the Bornaward granodiorite yielded an age of Hosseini et al. (2015) 1 i 6 1 520.7 ± 10.9 Ma ( Figure 13). Based on 32 analysed points, the mean age value (weighted mean) for the Bornaward granodiorite is 538.22 ± 2.48 Ma (Karimpour et al. 2011). ...
... In the southern part of Zeber kuh, south east of Yakhab village, granite underlies the predominant schists. Similar rock types are also present in the Taknar zone (Karimpour et al. 2011). The Zeber Kuh complex shows the tectonic features of the crush zone at the northern margin of the Lut lock, which is characterized by convergence and intercalation of regional faults and lineaments (Ahmadirouhani et al. 2017). ...
Late Neoproterozoic to Early Cambrian (Cadomian) magmatic rocks are abundant in Iran, but their occurrence in east-central Iran is voluminous. This paper reports, for the first time, on the Cadomian rocks of the eastern Iranian region known as Tapeh Tagh and deals with their geochemistry and uranium-lead (U-Pb) zircon ages. The Tapeh Tagh region contains masses of Cadomian meta-igneous rocks (including various types of granitic gneiss) and overlying meta-sedimentary rocks. The granitic gneisses show tectonic contact with metasedimentary rocks and their connection appears to have been obscured during the younger tectonic movements. The granitic gneisses show mylonitic texture with quartz ribbons and feldspar augen. Laser Ablation Inductively Coupled Plasma Mass Spectrometry U-Pb dating of zircon grains, separated from medium to coarse-grained gneissic rocks, consistently yielded near concordant to discordant pairs of 527 ± 5 and 522 ± 10 Ma. Geochemically, these rocks show a felsic composition with SiO2 content varying from 70.30 to 79.63 wt.%, a high content of FeO(t), alkalis, and incompatible trace elements (Zr, Nb), along with high ratios of Ga/Al and FeO(t)/MgO. They have fractionated rare earth element (REE) patterns with La/Yb = 9.1–24.7. Eu shows depletion with Eu/Eu*<1. The highly fractionated granites of the Tapeh Tagh are geochemically classified into the volcanic arc granites (VAG) and within plate granite.The granitic gneisses are geochemically and geochronologically similar to other Cadomian granites and gneisses in other parts of Iran as well as the Cadomian magmatic rocks from Turkey. These widely disseminated Cadomian basement rocks in Iran and Turkey are considered as fragments of Neoproterozoic to Early Cambrian continental arcs that formed the northern active margin of Gondwanaland.
... Late Neoproterozoic-Early Cambrian ages for the basement are reported from Central Iran (Ramezani & Tucker, 2003;Rossetti et al., 2015;Verdel et al., 2007), the Sanandaj-Sirjan Zone (Hassanzadeh et al., 2008), northeast Iran (Karimpour, Lang Farmer, Stern, & Salati, 2011;Shafaii Moghadam, Khademim et al., 2015; Shafaii Moghadam et al., 2016;Shafaii Moghadam, Griffin, et al., 2017), northwest Iran (Azizi, Chung, Tanaka, & Asahara, 2011;Hassanzadeh et al., 2008;Jamshidi Badr, Collins, Masoudi, Cox, & Mohajjel, 2013;Nutman, Mohajjel, Bennett, & Fergusson, 2014;Saki, 2010;Shahzeidi et al., 2016;Shakerardakani et al., 2015), and from the Urumieh-Dokhtar Magmatic Arc (UDMA; Babazadeh, Ghorbani, Cottle, & Bröcker, 2019;Chiu et al., 2017;Shahsavari Alavijeh, Rashidnejad-Omran, Toksoy-Köksal, Xu, & Ghalamghash, 2019; Figure 1). ...
... Our finding is comparable with previous workers that point to either incorporation of sediments or inheritance from the mantle granodiorite, granitic gneisses, gabbro, and associated volcanics is considered as Iran's continental crust (Hassanzadeh et al., 2008;Jamshidi Badr et al., 2013;Karimpour et al., 2011;Ramezani & Tucker, 2003;Rossetti et al., 2015;Shakerardakani et al., 2015). The Neoproterozoic inherited zircons from the UDMA are comparable to the magmatic zircon ages in the SSZ, Central Iran, and northwest Iran (e.g., Nutman et al., 2014;Shahzeidi et al., 2016;Shakerardakani et al., 2015;Figure 7c, d). ...
Laser ablation ICP‐MS U–Pb dating on inherited zircons from Neogene volcanic rocks of the Tafresh area in the central part of Urumieh‐Dokhtar Magmatic Arc (UDMA) yielded Paleoproterozoic, Late Neoproterozoic–Early Cambrian, Carboniferous, and Cretaceous ages. These ages improve our understanding of the geodynamical evolution of central UDMA. The 2,379 Ma age (i.e., Paleoproterozoic) is the oldest age reported in the central UDMA and is similar to the age of detrital zircons from Central Iran. The Paleoproterozoic zircons may come from the African Craton and fed from Central Iran sedimentary sequences. The Late Neoproterozoic–Early Cambrian ages (605 ± 11 Ma to 533 ± 9.2 Ma) indicate a basement for the UDMA, which is similar to that of the Sanandaj‐Sirjan Zone, Central Iran, and northwest Iran. The Carboniferous zircon age (328.4 Ma) is interpreted as being derived from the Eurasian arc produced by northward subduction of the Paleo‐Tethys Oceanic Plate. The Late Cretaceous zircon ages (106 to 71.2 Ma) might be regarded as indicating the Late Cretaceous magmatic episode, marking the subduction of oceanic crust that followed the Neo‐Tethys subduction.
... F. Mousivand et al. Ore Geology Reviews 95 (2018) 974-1007 and 552 Ma (Karimpour et al., 2011;Monazzami Bagherzadeh et al., 2015) Bornavard granitoid bodies. The calc-alkaline Bornavard granitoid (Homam, 1992;Sepahi Garou, 1992;Esmaeili et al., 1998;Zirjanizadeh et al., 2007;Karimpour et al., 2011) provides evidence of arc volcano-plutonism in the Taknar inlier. ...
... Ore Geology Reviews 95 (2018) 974-1007 and 552 Ma (Karimpour et al., 2011;Monazzami Bagherzadeh et al., 2015) Bornavard granitoid bodies. The calc-alkaline Bornavard granitoid (Homam, 1992;Sepahi Garou, 1992;Esmaeili et al., 1998;Zirjanizadeh et al., 2007;Karimpour et al., 2011) provides evidence of arc volcano-plutonism in the Taknar inlier. It is inferred that this arc magmatism commenced much earlier than 540 Ma (Ramezani and Tucker, 2003) and the Taknar formation that hosts the Taknar VMS deposits may have formed in such an intra-arc setting (Fig. 26). ...
... Generally, the primitive arc/arc/intra-arc settings of the Iranian VMS deposits are characterized by well-developed tholeiitic to transitional andesitic-basaltic volcanism (e.g., Bavanat deposit, Mousivand et al., 2007Mousivand et al., , 2012Sargaz deposit, Badrzadeh et al., 2011), calc-alkaline to transitional andesitic-dacitic volcanic-subvolcanic complexes (e.g., Barika deposit, Yarmohammadi et al., 2008a,b;Azizi et al., 2006;Moinevaziri, 2007, 2009;Azizi and Jahangiri, 2008), and calc-alkaline or calc-alkaline to alkaline bimodal rhyolite-basalt volcanic rocks intercalated with sedimentary rocks, such as at the Chahgaz (Mousivand, 2010;Mousivand et al., 2011), Taknar (Razzaghmanesh, 1968;Homam, 1992;Sepahi Garou, 1992;Esmaeili et al., 1998;Zirjanizadeh et al., 2007;Karimpour et al., 2011) and Dorreh deposits (Emami et al., 1993;Nazari et al., 1994). ...
There are a lot of volcanogenic massive sulfide (VMS) deposits and numerous mineral occurrences of this type of mineralization in Iran. VMS deposits can be subdivided into different types, and Iranian VMS deposits represent all of the recognized types: mafic-, pelitic-mafic-, bimodal-mafic-, bimodal-felsic- and felsic-siliciclastic-type, and these are hosted in different tectonic settings. The major tectonic/structural zones of Iran that host VMS deposits are: (1) the Sanandaj-Sirjan Zone (SSZ; North: NSSZ; South: SSSZ), (2) the Urumieh-Dokhtar magmatic assemblage (UDMA), (3) the Central Iran (Sabzevar Zone/SZ and Kashmar-Kerman Zone/KKZ), and (4) the Mesozoic ophiolites (MO). The VMS deposits were formed during discrete time periods: (1) Late Neoproterozoic-Early Cambrian (Taknar bimodal-felsic-type Cu-Zn-Au-Ag-Pb and Nohkouhi felsic-siliciclastic-type Cu deposits in the KKZ), (2) Late Triassic-Early Jurassic (e.g., Sargaz bimodal-mafic-type Cu-Zn deposit in the SSSZ), (3) Early Jurassic (Bavanat pelitic-mafic-type Cu-Zn-Ag deposit in the SSSZ), (4) Middle Jurassic (e.g., Chahgaz felsic-siliciclastic-type Zn-Pb-Cu deposit in the SSSZ), (5) Cretaceous (e.g., Barika bimodal-felsic-type in the NSSZ, Nudeh and Garmab-e-Paein pelitic-mafic-type Cu-Ag in the SZ, Sheikh-Ali and Zurabad mafic-type Cu deposits which occur in the Upper Cretaceous ophiolites), and (6) Eocene-Oligocene (e.g., Dorreh and Varandan bimodal-felsic-type deposits in the UDMA). Magmatic arcs (volcanic primitive arcs, arc/intra-arc rifts and back-arc basins) are the principal plate tectonic setting for the Iranian VMS deposits. All of the VMS deposits of the SSZ and UDMA formed within Mesozoic and Tertiary arcs, respectively, that developed during subduction of the Neo-Tethyan crust beneath the Iranian plate. Intra-oceanic or continental mature back-arc spreading settings are recognized in the Neo-Tethys domain in Iran (i.e., MO), and these host several Cu-rich VMS deposits. The host rock sequences for all deposits can be divided into three groups: (1) bimodal calc-alkaline; (2) bimodal tholeiitic; and (3) tholeiitic basaltic. The sulfur isotope compositions of the VMS deposits in the SSZ indicate that significant sources for sulfur in these deposits were inorganically reduced seawater sulfate and sulfur leached from the footwall volcanic rocks. The main time period of the formation of VMS mineralization in Iran was form Jurassic to Cretaceous. The SSZ (particularly the SSSZ) is the most attractive metallogenic province in Iran for VMS exploration because it hosts different VMS deposit types, including the precious metal enriched Barika bimodal-felsic-type deposit in the NSSZ, and the Bavanat pelitic-mafic-type (mafic-siliciclastic-type), Chahgaz and Chahanjir felsic-siliciclastic-type, and Sargaz, Ghalerigi and Siahmadan bimodal-mafic-type deposits in the SSSZ.
... Late Neoproterozoic-Cambrian (ca. 600-500 Ma) magmatism represents the first major magmatic episode with widespread emplacement of granitoids, granitic gneisses and associated volcanics as the crystalline basement of Iran (Ramezani and Tucker, 2003;Guest et al., 2006;Bagheri and Stampfli, 2008;Hassanzadeh et al., 2008;Azizi et al., 2011a;Karimpour et al., 2011;Rahmati-Ilkhchi et al., 2011;Jamshidi Badr et al., 2013;Balaghi Einalou et al., 2014;Nutman et al., 2014;Bagherzadeh et al., 2015;Faramarzi et al., 2015;Hosseini et al., 2015;Moghadam et al., 2015aMoghadam et al., , 2016Rossetti et al., 2015;Shakerardakani et al., 2015;Shahzeidi et al., 2016). This stage of magmatism in Iran is interpreted as part of the Cadomian igneous activities resulting from the subduction of the Proto-Tethys along the northern Gondwanan margin (Rossetti et al., 2015;Moghadam et al., 2016). ...
This study presents coupled zircon U-Pb and Hf isotopic analyses of 82 igneous rocks that are mainly from the Urumieh-Dokhtar magmatic arc (UDMA) and Sanandaj-Sirjan zone (SSZ), Iran, together with additional 11 samples from Armenia, along the central part of the Neotethyan orogenic belt. The results provide an overview of the isotopic variations for several important magmatic stages, which can improve our understanding of magmatic and crustal evolution regarding the life cycles of Tethys oceans during the past ∼600 Myr in Iran and adjacent regions. Late Neoproterozoic-Cambrian (595-511 Ma) basement rocks in the SSZ and Central Iran, which were part of the Cadomian magmatic arc, yield zircon εHf(T) values from +11 to -3 and are attributed to have partially evolved with juvenile magmas in the Arabian-Nubian Shield along the northern margin of Gondwana. Carboniferous (349-311 Ma) A-type granitoids in the northwestern SSZ show mostly positive zircon εHf(T) values from +5 to -1, and they are interpreted as the product involving a moderate mantle contribution in an extensional environment affiliated with the initial rifting of the Neotethys. Late Triassic (219-203 Ma) granitoids in the eastern Alborz give slightly lower zircon εHf(T) values between +3 and -3 as a result of the progress of closing the Paleotethys. Middle Jurassic (∼165 Ma) granitoids in the SSZ and Central UDMA, representing an early phase of Neotethyan subduction-related magmatism, exhibit similar zircon εHf(T) values from +5 to -3, implying an origin of mixed juvenile and reworked sources to form the magmas. Late Cretaceous (81-72 Ma) intrusive rocks in the Southeast UDMA yield bimodal zircon εHf(T) values from +15 to +11 in the Jiroft and from +5 to -9 in the Bazman areas, suggesting that the latter involves a reworked crustal component. At the latest Cenozoic, magmatic rocks with ages <55 Ma that occurred widely across Iran and Armenia before and after the Arabia-Eurasia collision give dominantly positive zircon εHf(T) values ranging between +15 and -1, except for the Eocene granitoids in Central Iran, which have remarkably lower zircon εHf(T) values down to -7. Therefore, these Cenozoic rocks yield younger zircon Hf crustal model ages (TDMC), mainly from ca. 1.2 to 0.2 Ga, than the Late Neoproterozoic-Mesozoic rocks. As the whole, the highly radiogenic Hf isotopes with positive εHf(T) values recorded by most (∼90%) of the measured magmatic zircons from Iran suggest that the mantle input has played a significant and long-standing role in the magmatic genesis and crustal growth throughout the Mesozoic and Cenozoic evolution in this particular part of the Tethyan orogenic belt.
... (Karimpour et al., 2011; Rahmati- Ilkhchi et al., 2011) ...
... The Dorud-Azna area belongs to the Complexly Deformed sub-zone. This area contains Ramezani and Tucker (2003); (2) Hassanzadeh et al. (2008); (3) Karimpour et al. (2011); (4) Jamshidi Badr et al. (2012); (5) Nutman et al. (2014). (b) Tectonic sketch map of western Iran (modified after Mohajjel et al., 2003) showing the division of the Sanandaj-Sirjan metamorphic zone into five sub-zones. ...
... In Central Iran east of the SSMZ, several areas expose Panafrican granites and their ages range from 522 ± 23 Ma to 601 ± 22 Ma, with a majority between ca. 530 and 550 Ma ( Fig. 3) ( Hassandzadeh et al., 2008;Jamshidi Badr et al., 2012;Karimpour et al., 2011;Ramezani and Tucker, 2003). From In the southwest of Kerman, the Siah-Kuh granitoid stock is part of the Triassic-Cretaceous intrusions in the southern SSMZ. ...
The Dorud–Azna region of the Sanandaj–Sirjan metamorphic zone (SSMZ) in NW Iran is part of the Zagros orogenic belt and exposes an amphibolite-grade metamorphic succession of mixed continental (e.g., the granitic Galeh–Doz orthogneiss) and oceanic or rift (e.g., various amphibolites) origin, which is intruded by the Darijune gabbro. Laser-ablation ICP–MS U–Pb zircon ages of 608 ± 18 Ma and 588 ± 41 Ma of the granitic Galeh–Doz orthogneiss indicate a Panafrican basement similar to that of the Yazd block of Central Iran.We therefore interpret this part of the SSMZ to represent a previously subducted part of the Panafrican basement of the Iranian microcontinent. Based on geochemistry, amphibolites and metagabbros from the Amphibolite unit representially potentially the cover on the Panafrican Galeh–Doz orthogneiss are interpreted to have their origin in a likely Upper Paleozoic to Mesozoic rift or E-MORB ophiolite succession. One of the metagabbros, here termed Dare- Hedavand metagabbro yield a 206Pb/238U mean age of 314.6 ± 3.7 Ma. Talc-bearing greenschists to epidote amphibolites of the Triassic June complex formed in a similar, but younger environment. Furthermore, the metamorphic
complex is intruded by the Darijune gabbro, which yields a mean ICP–MS U–Pb zircon age of 170.2 ± 3.1 Ma. The final stage of likely Jurassic greenschist facies-grade metamorphism postdates the gabbro intrusion. We interpret the Darijune gabbro to have resulted from the initial subduction of Neotethyan oceanic lithosphere in a continental arc setting. The new data combined with data from literature indicate that the SSMZ represents a tectonic element of a mixed continental and oceanic origin, likely accreted to Central Iran during
a Jurassic tectonic process. The new data also constrains thick-skinned nappe stacking within the Sanandaj– Sirjan zone.
