Z. Gharehchahi; M. Moayyed; J. Ahmadiyan; M. Murata
Abstract
Sungun and Haftcheshme mines located in Arasbaran volcano-plutonic complex in the North West of Azarbaijan province. lamprophyric dikes of Sungun with younger age Oligo-Miocene including minerals, biotite, plagioclase and pyroxene, porphyritic texture, classified part of the calc-alkaline and kersantite ...
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Sungun and Haftcheshme mines located in Arasbaran volcano-plutonic complex in the North West of Azarbaijan province. lamprophyric dikes of Sungun with younger age Oligo-Miocene including minerals, biotite, plagioclase and pyroxene, porphyritic texture, classified part of the calc-alkaline and kersantite and The area lamprophyric rocks are intruded in to Sungun quartz - monzonite. lamprophyric dikes of haftcheshme with with younger age Oligo-Miocene including minerals, biotite, alkali feldspar and pyroxene, the main textures microlitic porphyy and flow, Calc-alkaline Lamprophyre component - are classified minette and The area lamprophyric rocks are intruded in to Haftcheshme quartz - diorite. The behavior of trace elements studied by the means of spider diagrams show low enrichment of LREE relative to MREE and HREE. Review geochemical characteristics of the study show that the origin of mantle-derived magmas essentially lamprophyres. The lamprophyric rocks are generated from calc-alkaline lamprophyrecomponent, related to magmatic arc tectonic setting and these lamprophyres have gneated from lamprophyre low degree of partial melting of garnet lherzolite.
A. Kananian; F. Sarjoughian; J. Ahmadian
Abstract
The Kuh-e Dom intrusion is a small section of Upper Eocene Urumieh- Dokhtar magmatic belt in the Central Iran tectonic zone. This intrusion is composed of two separate phases which include an acidic and intermediate- mafic units. The acidic rocks consist of monzogranite, granodiorite, quartz monzonite ...
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The Kuh-e Dom intrusion is a small section of Upper Eocene Urumieh- Dokhtar magmatic belt in the Central Iran tectonic zone. This intrusion is composed of two separate phases which include an acidic and intermediate- mafic units. The acidic rocks consist of monzogranite, granodiorite, quartz monzonite and quartz monzodiorite whereas the intermediate-mafic rocks comprise gabbro, diorite, quartz diorite, monzodiorite and monzonite. Mafic microgranular enclaves of dioritic, quartz dioritic, monzodioritic and quartz monzodioritic composition are common in the acidic rocks. Based on geochemical data, magma mixing along with fractional crystallization has important role in evolution of the plutonic rocks. Also, Kuh-e Dom intrusive rocks have low TiO2, P2O5 and Nb/Zr ratio which are characteristics of active continental margin. The isotopic signature of plutonic rocks is not exactly like those of mantle- or crustal-derived magma, but these rocks have some features commonly found both in the crustal and mantlic sources so that the enclaves tend to illustrate mantlic composition and the acidic rocks tend to show crustal composition, but the intermediate- mafic rocks are in the range from acidic rocks to enclaves. This result along with field and petrographical studies indicate that magma mixing/magma or mingling processes may play an important role in evolution of the intrusion. The upper mantle magma forming the microgranular enclaves, after emplacement in the crust may lead to partial melting of lower crust and because of magma mixing between crustal and mantlic melts, the mafic to intermediate rocks may form.