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Heidarian Shahri M. R. - One of the best experts on this subject based on the ideXlab platform.

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward complex (Bardaskan-NE Iran)
    Geological Survey of Iran, 2014
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward granitoids in the Taknar zone are located in the northeast of the central Iranian block in northeast Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city and 28 km northwest of Bardaskan city. Taknar zone is an exotic block, bordered by two major faults, the Great Kavir fault in the south and Rivash fault in the north. Intrusive Rocks of the study area, called the Bornaward granitoid complex (BGC), include of granite, alkali granite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite, diorite and gabbro intruded into the center of Taknar zone. These intrusive Rocks affected low grade metamorphism. The results of U-Pb zircon dating on two granite samples, one belonging to the Taknar mine west of the study area and the other the Bornaward granitoids in the eastern part of study area, and also one granodiorite the Taknar mine area and one diorite the Bornaward area, yield ages of the granites as 540.5±2.9 Ma (Taknar mine area) and 550.41 3.21,-4.54 Ma (Bornaward area), the granodiorite as 550±6.9 Ma and diorite as 551.96±4.32 Ma, all Late Neoproterozoic. The Bornaward intrusive bodies are classified as belonging to the ilmenite-series of reduced granitoids. Some small high magnetite-granite and tonalite outcrops in the study area are classified as belonging to the magnetite-series of oxidized granitoids. Chemically, most granitoids of the study area are S-type middle-high metaluminous to slightlymiddle peraluminous and belong to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichments in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) elements and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REEs) plots indicate minor enrichments of LREEs in comparison with HREEs, with (La/Yb)N between 1.04 -7.90 and total of REEs of the samples between 44.8 ppm (minimum) and 293.5 ppm (maximum) with strong negative anomaly of Eu compared to other Rare Earth elements. The Bornaward granitoid have an initial 87Sr/86Sr and 143Nd/144Nd ranging 0.703514 to 0.716888 and 0.511585 to 0.512061, respectively, when reCalculated to an age of 550 to 538 Ma, consistent with the new radiometric age results. Initial εNd isotope values for granite, granodiorite and diorite range -6.73 to 2.52. TDM age of the BGC is 1.08-1.70 Ga. This indicates that the Bornaward granitoid complex (BGC) derived partial melting of distinct basement source regions with very high initial 87Sr/86Sr and underwent extensive crustal contamination

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward Complex (Bardaskan-NE Iran)
    Elsevier, 2026
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward Granitoid Complex (BGC) in the Taknar Zone is located in the northeast of Central Iranian Block. The BGC consists of granite, alkaligranite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite and diorite that have intruded into the center of Taknar Zone. These intrusive Rocks affected by low grade metamorphism. Because of there are no reliable isotope dating data, for the Bornaward Granitoid Complex Rocks have been proposed discordant ages (Jurassic, Cretaceous or even younger ages) by many studies. In the present study, new isotopic information based on zircon U–Pb dating has revealed the origin and time of the formation of the BGC. These new results do not confirm previously proposed ages. The results obtained from zircon U–Pb dating of the BGC Rocks suggest late-Neoproterozoic (Precambrian) age (540–550 Ma). The Bornaward Granitoid Complex is middle-high metaluminous to lower-middle peraluminous and belongs to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichment in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REE) plots indicate minor enrichment of LREE compared to HREE, and strong negative anomaly of Eu compared to other Rare Earth Elements. Furthermore, initial 87Sr/86Sr and 143Nd/144Nd range from 0.70351 to 0.71689 and 0.511585 to 0.512061, respectively, and initial εNd isotope values for granite, granodiorite and diorite range from −6.73 to 2.52. These all indicate that the BGC has derived from partial melting of distinct basement source regions with very high initial 87Sr/86Sr and undergoing extensive crustal contamination (S-type granite)

Monazzami Bagherzadeh R. - One of the best experts on this subject based on the ideXlab platform.

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward complex (Bardaskan-NE Iran)
    Geological Survey of Iran, 2014
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward granitoids in the Taknar zone are located in the northeast of the central Iranian block in northeast Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city and 28 km northwest of Bardaskan city. Taknar zone is an exotic block, bordered by two major faults, the Great Kavir fault in the south and Rivash fault in the north. Intrusive Rocks of the study area, called the Bornaward granitoid complex (BGC), include of granite, alkali granite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite, diorite and gabbro intruded into the center of Taknar zone. These intrusive Rocks affected low grade metamorphism. The results of U-Pb zircon dating on two granite samples, one belonging to the Taknar mine west of the study area and the other the Bornaward granitoids in the eastern part of study area, and also one granodiorite the Taknar mine area and one diorite the Bornaward area, yield ages of the granites as 540.5±2.9 Ma (Taknar mine area) and 550.41 3.21,-4.54 Ma (Bornaward area), the granodiorite as 550±6.9 Ma and diorite as 551.96±4.32 Ma, all Late Neoproterozoic. The Bornaward intrusive bodies are classified as belonging to the ilmenite-series of reduced granitoids. Some small high magnetite-granite and tonalite outcrops in the study area are classified as belonging to the magnetite-series of oxidized granitoids. Chemically, most granitoids of the study area are S-type middle-high metaluminous to slightlymiddle peraluminous and belong to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichments in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) elements and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REEs) plots indicate minor enrichments of LREEs in comparison with HREEs, with (La/Yb)N between 1.04 -7.90 and total of REEs of the samples between 44.8 ppm (minimum) and 293.5 ppm (maximum) with strong negative anomaly of Eu compared to other Rare Earth elements. The Bornaward granitoid have an initial 87Sr/86Sr and 143Nd/144Nd ranging 0.703514 to 0.716888 and 0.511585 to 0.512061, respectively, when reCalculated to an age of 550 to 538 Ma, consistent with the new radiometric age results. Initial εNd isotope values for granite, granodiorite and diorite range -6.73 to 2.52. TDM age of the BGC is 1.08-1.70 Ga. This indicates that the Bornaward granitoid complex (BGC) derived partial melting of distinct basement source regions with very high initial 87Sr/86Sr and underwent extensive crustal contamination

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward Complex (Bardaskan-NE Iran)
    Elsevier, 2026
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward Granitoid Complex (BGC) in the Taknar Zone is located in the northeast of Central Iranian Block. The BGC consists of granite, alkaligranite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite and diorite that have intruded into the center of Taknar Zone. These intrusive Rocks affected by low grade metamorphism. Because of there are no reliable isotope dating data, for the Bornaward Granitoid Complex Rocks have been proposed discordant ages (Jurassic, Cretaceous or even younger ages) by many studies. In the present study, new isotopic information based on zircon U–Pb dating has revealed the origin and time of the formation of the BGC. These new results do not confirm previously proposed ages. The results obtained from zircon U–Pb dating of the BGC Rocks suggest late-Neoproterozoic (Precambrian) age (540–550 Ma). The Bornaward Granitoid Complex is middle-high metaluminous to lower-middle peraluminous and belongs to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichment in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REE) plots indicate minor enrichment of LREE compared to HREE, and strong negative anomaly of Eu compared to other Rare Earth Elements. Furthermore, initial 87Sr/86Sr and 143Nd/144Nd range from 0.70351 to 0.71689 and 0.511585 to 0.512061, respectively, and initial εNd isotope values for granite, granodiorite and diorite range from −6.73 to 2.52. These all indicate that the BGC has derived from partial melting of distinct basement source regions with very high initial 87Sr/86Sr and undergoing extensive crustal contamination (S-type granite)

Ian S Williams - One of the best experts on this subject based on the ideXlab platform.

  • post collisional volcanism in a sinking slab setting crustal anatectic origin of pyroxene andesite magma caldear volcanic group neogene alboran volcanic province southeastern spain
    Lithos, 1998
    Co-Authors: H P Zeck, A B Kristensen, Ian S Williams
    Abstract:

    Abstract Caldear Volcanic Group (CVG), a stratigraphically well defined, Calc-Alkaline Rock complex within Sa de Gata in the eastern part of the Alpine Betic mountain chain, S Spain, consists of three distinct formations: Hernandez pyroxene andesites, Bujo hornblende-bearing pyroxene andesites and Viuda hornblende-bearing pyroxene dacites–rhyolites. The letter Rock formation may have developed through crystal fractionation of mainly plagioclase and pyroxenes, however there is no direct relation between two formations. CVG has a domainal structure with a northeastern domain where Hernandez formation is overlain by Bujo formation while Viuda formation is absent, and a southwestern domain where Viuda formation forms the only fractionate after Hernandez formation. Hernandez parent magma is thought generated through crustal anatexis by dehydration melting of a predominantly amphibolitic source Rock complex which was formed by metamorphism from c. 500 Ma volcano-sedimentary parent material. The domainal structure of CVG is explained by compositional variation within this protogenetic complex. Single crystal U–Pb ages of c. 500 Ma to 1800 Ma for inherited zircon support the presence of clastic material of Proterozoic derivation within the original volcano-sedimentary complex. Regional study of syn-collisional Rock formations (Alpine nappe complexes) indicate that the collisional tectonic stage in the Betic-Rif orogenic belt took place rather early (25–30 Ma?) and was followed by a stage of rapid regional Rock uplift, fast cooling (c. 500°C/my) and extensional tectonics in the period 22–17 Ma. This later tectonic stage was set into motion by slab break-off which set the stage for a high temperature regime in the overlying lithosphere, providing the framework for the crustal melting and magma production responsible for the Calc-Alkaline Rocks of Alboran volcanic province. Miocene zircon with ages ranging from c. 17 to 11 Ma indicate a rather protracted magmatic development prior to eruption at c. 11 Ma. Post-collisional character of Caldear Volcanic Group thus seems well established.

Karimpour M. H. - One of the best experts on this subject based on the ideXlab platform.

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward complex (Bardaskan-NE Iran)
    Geological Survey of Iran, 2014
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward granitoids in the Taknar zone are located in the northeast of the central Iranian block in northeast Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city and 28 km northwest of Bardaskan city. Taknar zone is an exotic block, bordered by two major faults, the Great Kavir fault in the south and Rivash fault in the north. Intrusive Rocks of the study area, called the Bornaward granitoid complex (BGC), include of granite, alkali granite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite, diorite and gabbro intruded into the center of Taknar zone. These intrusive Rocks affected low grade metamorphism. The results of U-Pb zircon dating on two granite samples, one belonging to the Taknar mine west of the study area and the other the Bornaward granitoids in the eastern part of study area, and also one granodiorite the Taknar mine area and one diorite the Bornaward area, yield ages of the granites as 540.5±2.9 Ma (Taknar mine area) and 550.41 3.21,-4.54 Ma (Bornaward area), the granodiorite as 550±6.9 Ma and diorite as 551.96±4.32 Ma, all Late Neoproterozoic. The Bornaward intrusive bodies are classified as belonging to the ilmenite-series of reduced granitoids. Some small high magnetite-granite and tonalite outcrops in the study area are classified as belonging to the magnetite-series of oxidized granitoids. Chemically, most granitoids of the study area are S-type middle-high metaluminous to slightlymiddle peraluminous and belong to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichments in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) elements and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REEs) plots indicate minor enrichments of LREEs in comparison with HREEs, with (La/Yb)N between 1.04 -7.90 and total of REEs of the samples between 44.8 ppm (minimum) and 293.5 ppm (maximum) with strong negative anomaly of Eu compared to other Rare Earth elements. The Bornaward granitoid have an initial 87Sr/86Sr and 143Nd/144Nd ranging 0.703514 to 0.716888 and 0.511585 to 0.512061, respectively, when reCalculated to an age of 550 to 538 Ma, consistent with the new radiometric age results. Initial εNd isotope values for granite, granodiorite and diorite range -6.73 to 2.52. TDM age of the BGC is 1.08-1.70 Ga. This indicates that the Bornaward granitoid complex (BGC) derived partial melting of distinct basement source regions with very high initial 87Sr/86Sr and underwent extensive crustal contamination

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward Complex (Bardaskan-NE Iran)
    Elsevier, 2026
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward Granitoid Complex (BGC) in the Taknar Zone is located in the northeast of Central Iranian Block. The BGC consists of granite, alkaligranite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite and diorite that have intruded into the center of Taknar Zone. These intrusive Rocks affected by low grade metamorphism. Because of there are no reliable isotope dating data, for the Bornaward Granitoid Complex Rocks have been proposed discordant ages (Jurassic, Cretaceous or even younger ages) by many studies. In the present study, new isotopic information based on zircon U–Pb dating has revealed the origin and time of the formation of the BGC. These new results do not confirm previously proposed ages. The results obtained from zircon U–Pb dating of the BGC Rocks suggest late-Neoproterozoic (Precambrian) age (540–550 Ma). The Bornaward Granitoid Complex is middle-high metaluminous to lower-middle peraluminous and belongs to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichment in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REE) plots indicate minor enrichment of LREE compared to HREE, and strong negative anomaly of Eu compared to other Rare Earth Elements. Furthermore, initial 87Sr/86Sr and 143Nd/144Nd range from 0.70351 to 0.71689 and 0.511585 to 0.512061, respectively, and initial εNd isotope values for granite, granodiorite and diorite range from −6.73 to 2.52. These all indicate that the BGC has derived from partial melting of distinct basement source regions with very high initial 87Sr/86Sr and undergoing extensive crustal contamination (S-type granite)

Rahimi B. - One of the best experts on this subject based on the ideXlab platform.

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward complex (Bardaskan-NE Iran)
    Geological Survey of Iran, 2014
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward granitoids in the Taknar zone are located in the northeast of the central Iranian block in northeast Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city and 28 km northwest of Bardaskan city. Taknar zone is an exotic block, bordered by two major faults, the Great Kavir fault in the south and Rivash fault in the north. Intrusive Rocks of the study area, called the Bornaward granitoid complex (BGC), include of granite, alkali granite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite, diorite and gabbro intruded into the center of Taknar zone. These intrusive Rocks affected low grade metamorphism. The results of U-Pb zircon dating on two granite samples, one belonging to the Taknar mine west of the study area and the other the Bornaward granitoids in the eastern part of study area, and also one granodiorite the Taknar mine area and one diorite the Bornaward area, yield ages of the granites as 540.5±2.9 Ma (Taknar mine area) and 550.41 3.21,-4.54 Ma (Bornaward area), the granodiorite as 550±6.9 Ma and diorite as 551.96±4.32 Ma, all Late Neoproterozoic. The Bornaward intrusive bodies are classified as belonging to the ilmenite-series of reduced granitoids. Some small high magnetite-granite and tonalite outcrops in the study area are classified as belonging to the magnetite-series of oxidized granitoids. Chemically, most granitoids of the study area are S-type middle-high metaluminous to slightlymiddle peraluminous and belong to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichments in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) elements and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REEs) plots indicate minor enrichments of LREEs in comparison with HREEs, with (La/Yb)N between 1.04 -7.90 and total of REEs of the samples between 44.8 ppm (minimum) and 293.5 ppm (maximum) with strong negative anomaly of Eu compared to other Rare Earth elements. The Bornaward granitoid have an initial 87Sr/86Sr and 143Nd/144Nd ranging 0.703514 to 0.716888 and 0.511585 to 0.512061, respectively, when reCalculated to an age of 550 to 538 Ma, consistent with the new radiometric age results. Initial εNd isotope values for granite, granodiorite and diorite range -6.73 to 2.52. TDM age of the BGC is 1.08-1.70 Ga. This indicates that the Bornaward granitoid complex (BGC) derived partial melting of distinct basement source regions with very high initial 87Sr/86Sr and underwent extensive crustal contamination

  • U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward Complex (Bardaskan-NE Iran)
    Elsevier, 2026
    Co-Authors: Monazzami Bagherzadeh R., Karimpour M. H., Lang Farmer G., Stern C. R., Santos J. F., Rahimi B., Heidarian Shahri M. R.
    Abstract:

    The Bornaward Granitoid Complex (BGC) in the Taknar Zone is located in the northeast of Central Iranian Block. The BGC consists of granite, alkaligranite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite and diorite that have intruded into the center of Taknar Zone. These intrusive Rocks affected by low grade metamorphism. Because of there are no reliable isotope dating data, for the Bornaward Granitoid Complex Rocks have been proposed discordant ages (Jurassic, Cretaceous or even younger ages) by many studies. In the present study, new isotopic information based on zircon U–Pb dating has revealed the origin and time of the formation of the BGC. These new results do not confirm previously proposed ages. The results obtained from zircon U–Pb dating of the BGC Rocks suggest late-Neoproterozoic (Precambrian) age (540–550 Ma). The Bornaward Granitoid Complex is middle-high metaluminous to lower-middle peraluminous and belongs to tholeiite, Calc-Alkaline to high-K Calc-Alkaline Rock series with enrichment in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REE) plots indicate minor enrichment of LREE compared to HREE, and strong negative anomaly of Eu compared to other Rare Earth Elements. Furthermore, initial 87Sr/86Sr and 143Nd/144Nd range from 0.70351 to 0.71689 and 0.511585 to 0.512061, respectively, and initial εNd isotope values for granite, granodiorite and diorite range from −6.73 to 2.52. These all indicate that the BGC has derived from partial melting of distinct basement source regions with very high initial 87Sr/86Sr and undergoing extensive crustal contamination (S-type granite)