Moshirabad granitoid body is located, as part of intrusive bodies, in Sanandaj-Sirjans zone and c... more Moshirabad granitoid body is located, as part of intrusive bodies, in Sanandaj-Sirjans zone and crops out elongated with east-west trend. Based on field observation as well as mineralogical characteristics, this suite consists of three main units; diorites, granodiorites and granites, followed by minor gabbros. Mineralogical and geochemical studies show that rocks of this suite are I-type, calcalkaline and from the point of view of saturation degree of aluminum (ASI) are metaluminous to weakly aluminous. Variation diagrams trends of major and trace elements indicate a continuous compositional range and comagmatic origin for these rocks. Trends of compatible-incompatible elements indicate the important role of fractional crystallization in the genesis of these rocks. Depletion in Ta, Nb, P and Ti and enrichment in Ce, K, Th, Rb and Ba are obvious in the spider diagrams of these samples. The enrichment in LILE and depletion in HFSE reveal the I-type metaluminous magmatism of volcanic ...
The Chekneh subvolcanic domes with dacite and trachydacite compositions from the Miocene is locat... more The Chekneh subvolcanic domes with dacite and trachydacite compositions from the Miocene is located 110 km NE of Sabzevar, and are parts of the North Sabzevar-South Ghochan magmatic belt. The dome rocks have porphyry, sieve, trachytic and glomeroporphyritic textures, consisting of plagioclase and amphibole. Primitive mantle normalized spider diagram and chondrite-normalized REE patterns of the study domes suggest that they are enriched in LREE and LILE and are depleted in HREE and HFSE. They are calc-alkaline with significant negative HFSE (e.g., P, Nb and Ti) anomalies and (La/Yb)N>12 which are characteristics of magmas formed in active continental margin. Based on SiO<sub>2</sub>, high Sr/Y, low K<sub>2</sub>O/Na<sub>2</sub>O and low Y, Yb, Cr and Mg<sup>#</sup> contents, the study rocks are similar to high-silica adakites (HSA). Thus, it seems that the parent magma of the study domes was originated from amphibole eclogite or gar...
Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite t... more Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite to rhyolite in composition which is cut by Jurasic sedimentary rocks, Eocene volcano-sedimentary rocks, Miocene sedimentary rocks and even occasionally Peliocene conglomerate. The main minerals of these rocks are plagioclase and amphibole with various textures such as felsitic porphyry, microlitic porphyry, glomero porphyry, sieve and flow textures. The calc-alkaline and metaluminous to peraluminous nature, enrichment in large ion lithophile elements (LILEs) and light rare earth elements (LREE) and depletion in heavy rare earth elements (HREE) in primitive mantle and chondrite normalized spider diagrams, along with high contents of Na 2 O, Al 2 O 3 , Sr, high ratio of Sr/Y and low ratio of K 2 O/Na 2 O and depletion in HFSEs in these rocks are characteristics of the young arc volcanics. Furthermore, these rocks display initial 87 Sr/ 86 Sr ratios of 0.70390 to 0.70562 and <Nd(t) values of-0.86 to +4.98 respectively, which show that they are originated from partial melting of oceanic slab with crustal contamination. Emplacement age of these rocks into the quchan-Esfarayen magmatic belt obtained with U-Pb dating on separated zircons of 17.83±0.24 to 8.50±0.34 Ma. The results show that parental magma of the rocks generated by partial melting of a garnetamphibolitic to eclogitic subducted Sabzevar Neo-Thethyan oceanic slab underneath the Binaloud continental lithospher. Presence of continental metamorphic and sedimentary xenoliths, corrosion and chemical disequilibrium of the phenocrysts and their sieve textures in plagioclase along with Sr-Nd isotopic ratios in these rocks indicate the operation of differentiation crystallization, assimilation and crustal contamination (AFC) in the genesis and evolution of igneous rocks of this belt.
Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite t... more Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite to rhyolite in composition which is cut by Jurasic sedimentary rocks, Eocene volcano-sedimentary rocks, Miocene sedimentary rocks and even occasionally Peliocene conglomerate. The main minerals of these rocks are plagioclase and amphibole with various textures such as felsitic porphyry, microlitic porphyry, glomero porphyry, sieve and flow textures. The calc-alkaline and metaluminous to peraluminous nature, enrichment in large ion lithophile elements (LILEs) and light rare earth elements (LREE) and depletion in heavy rare earth elements (HREE) in primitive mantle and chondrite normalized spider diagrams, along with high contents of Na 2 O, Al 2 O 3 , Sr, high ratio of Sr/Y and low ratio of K 2 O/Na 2 O and depletion in HFSEs in these rocks are characteristics of the young arc volcanics. Furthermore, these rocks display initial 87 Sr/ 86 Sr ratios of 0.70390 to 0.70562 and <Nd(t) values of-0.86 to +4.98 respectively, which show that they are originated from partial melting of oceanic slab with crustal contamination. Emplacement age of these rocks into the quchan-Esfarayen magmatic belt obtained with U-Pb dating on separated zircons of 17.83±0.24 to 8.50±0.34 Ma. The results show that parental magma of the rocks generated by partial melting of a garnetamphibolitic to eclogitic subducted Sabzevar Neo-Thethyan oceanic slab underneath the Binaloud continental lithospher. Presence of continental metamorphic and sedimentary xenoliths, corrosion and chemical disequilibrium of the phenocrysts and their sieve textures in plagioclase along with Sr-Nd isotopic ratios in these rocks indicate the operation of differentiation crystallization, assimilation and crustal contamination (AFC) in the genesis and evolution of igneous rocks of this belt.
Moshirabad granitoid body is located, as part of intrusive bodies, in Sanandaj-Sirjans zone and c... more Moshirabad granitoid body is located, as part of intrusive bodies, in Sanandaj-Sirjans zone and crops out elongated with east-west trend. Based on field observation as well as mineralogical characteristics, this suite consists of three main units; diorites, granodiorites and granites, followed by minor gabbros. Mineralogical and geochemical studies show that rocks of this suite are I-type, calcalkaline and from the point of view of saturation degree of aluminum (ASI) are metaluminous to weakly aluminous. Variation diagrams trends of major and trace elements indicate a continuous compositional range and comagmatic origin for these rocks. Trends of compatible-incompatible elements indicate the important role of fractional crystallization in the genesis of these rocks. Depletion in Ta, Nb, P and Ti and enrichment in Ce, K, Th, Rb and Ba are obvious in the spider diagrams of these samples. The enrichment in LILE and depletion in HFSE reveal the I-type metaluminous magmatism of volcanic ...
The Chekneh subvolcanic domes with dacite and trachydacite compositions from the Miocene is locat... more The Chekneh subvolcanic domes with dacite and trachydacite compositions from the Miocene is located 110 km NE of Sabzevar, and are parts of the North Sabzevar-South Ghochan magmatic belt. The dome rocks have porphyry, sieve, trachytic and glomeroporphyritic textures, consisting of plagioclase and amphibole. Primitive mantle normalized spider diagram and chondrite-normalized REE patterns of the study domes suggest that they are enriched in LREE and LILE and are depleted in HREE and HFSE. They are calc-alkaline with significant negative HFSE (e.g., P, Nb and Ti) anomalies and (La/Yb)N>12 which are characteristics of magmas formed in active continental margin. Based on SiO<sub>2</sub>, high Sr/Y, low K<sub>2</sub>O/Na<sub>2</sub>O and low Y, Yb, Cr and Mg<sup>#</sup> contents, the study rocks are similar to high-silica adakites (HSA). Thus, it seems that the parent magma of the study domes was originated from amphibole eclogite or gar...
Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite t... more Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite to rhyolite in composition which is cut by Jurasic sedimentary rocks, Eocene volcano-sedimentary rocks, Miocene sedimentary rocks and even occasionally Peliocene conglomerate. The main minerals of these rocks are plagioclase and amphibole with various textures such as felsitic porphyry, microlitic porphyry, glomero porphyry, sieve and flow textures. The calc-alkaline and metaluminous to peraluminous nature, enrichment in large ion lithophile elements (LILEs) and light rare earth elements (LREE) and depletion in heavy rare earth elements (HREE) in primitive mantle and chondrite normalized spider diagrams, along with high contents of Na 2 O, Al 2 O 3 , Sr, high ratio of Sr/Y and low ratio of K 2 O/Na 2 O and depletion in HFSEs in these rocks are characteristics of the young arc volcanics. Furthermore, these rocks display initial 87 Sr/ 86 Sr ratios of 0.70390 to 0.70562 and <Nd(t) values of-0.86 to +4.98 respectively, which show that they are originated from partial melting of oceanic slab with crustal contamination. Emplacement age of these rocks into the quchan-Esfarayen magmatic belt obtained with U-Pb dating on separated zircons of 17.83±0.24 to 8.50±0.34 Ma. The results show that parental magma of the rocks generated by partial melting of a garnetamphibolitic to eclogitic subducted Sabzevar Neo-Thethyan oceanic slab underneath the Binaloud continental lithospher. Presence of continental metamorphic and sedimentary xenoliths, corrosion and chemical disequilibrium of the phenocrysts and their sieve textures in plagioclase along with Sr-Nd isotopic ratios in these rocks indicate the operation of differentiation crystallization, assimilation and crustal contamination (AFC) in the genesis and evolution of igneous rocks of this belt.
Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite t... more Quchan-Esfarayen magmatic belt (north of Sabzevar) include Neogene adakitic domes with andesite to rhyolite in composition which is cut by Jurasic sedimentary rocks, Eocene volcano-sedimentary rocks, Miocene sedimentary rocks and even occasionally Peliocene conglomerate. The main minerals of these rocks are plagioclase and amphibole with various textures such as felsitic porphyry, microlitic porphyry, glomero porphyry, sieve and flow textures. The calc-alkaline and metaluminous to peraluminous nature, enrichment in large ion lithophile elements (LILEs) and light rare earth elements (LREE) and depletion in heavy rare earth elements (HREE) in primitive mantle and chondrite normalized spider diagrams, along with high contents of Na 2 O, Al 2 O 3 , Sr, high ratio of Sr/Y and low ratio of K 2 O/Na 2 O and depletion in HFSEs in these rocks are characteristics of the young arc volcanics. Furthermore, these rocks display initial 87 Sr/ 86 Sr ratios of 0.70390 to 0.70562 and <Nd(t) values of-0.86 to +4.98 respectively, which show that they are originated from partial melting of oceanic slab with crustal contamination. Emplacement age of these rocks into the quchan-Esfarayen magmatic belt obtained with U-Pb dating on separated zircons of 17.83±0.24 to 8.50±0.34 Ma. The results show that parental magma of the rocks generated by partial melting of a garnetamphibolitic to eclogitic subducted Sabzevar Neo-Thethyan oceanic slab underneath the Binaloud continental lithospher. Presence of continental metamorphic and sedimentary xenoliths, corrosion and chemical disequilibrium of the phenocrysts and their sieve textures in plagioclase along with Sr-Nd isotopic ratios in these rocks indicate the operation of differentiation crystallization, assimilation and crustal contamination (AFC) in the genesis and evolution of igneous rocks of this belt.
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