Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak
Nezam-Abad area is located in southwest of Shazand (Arak) which is a part of Sanandaj-Sirjan zone. Major intrusive rocks of Nezam-Abad are quartz diorite and minor amount of granodiorite. Leucogranitic, pegmatite dykes and quartz-tourmaline veins were intruded the quartz diorite. Quartz diorites are...
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| Format: | Article |
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Ferdowsi University of Mashhad
2010-08-01
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| Series: | Journal of Economic Geology |
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| Online Access: | https://econg.um.ac.ir/index.php/econg/article/view/3686 |
| _version_ | 1818991661914521600 |
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| author | Robabeh Jafari Moussa Noghreyan Mohammad Ali Mackizadeh Javad Ghanei Ardekanei |
| author_facet | Robabeh Jafari Moussa Noghreyan Mohammad Ali Mackizadeh Javad Ghanei Ardekanei |
| author_sort | Robabeh Jafari |
| collection | DOAJ |
| description | Nezam-Abad area is located in southwest of Shazand (Arak) which is a part of Sanandaj-Sirjan zone. Major intrusive rocks of Nezam-Abad are quartz diorite and minor amount of granodiorite. Leucogranitic, pegmatite dykes and quartz-tourmaline veins were intruded the quartz diorite. Quartz diorites are mainly composed of plagioclase, hornblende, biotite, quartz and pyroxene as major minerals. Major minerals of leucogranite are microcline, orthoclase, albite, quartz, biotite and muscovite. Accessory minerals consist of apatite, zircon, sphene, epidote, allanite, tourmaline and opaque. The presence of hydrous minerals like hornblende and biotite in these rocks indicate that the corresponding magma initially contained >3 wt% H2O (wet magma). The occurrences of garnet and andalusite minerals suggest assimilation process. Primary textures in these rocks are granular, granophyre, and poikilitic. Secondary textures are perthite, myrmekite, sericitization, chloritization and kaolinitization. Later hydrothermal activities and tectonic strains are factors for presence of perthite texture in leucogranite. K amount for sericitization of feldspars come from the K-feldspars and chloritization of biotite. Transformation of biotite to muscovite indicates the act of K rich fluid in later stages. On the basis of chemical analysis on the intrusive rocks, it is shown that the magma was calc-alkaline, metaluminous-peraluminous and medium-K to high-K. Study of major elements in Harker diagrams indicates Al2O3, FeO, Fe2O3 and CaO decrease with increasing of SiO2 and K2O and Na2O increase indicating that fractional crystallization may have played an important role in the formation of granitoid rocks from Nezam-Abad. |
| first_indexed | 2024-12-20T20:13:49Z |
| format | Article |
| id | doaj.art-1c15ce34ec4a4bbbbfc23ae3e6bfc425 |
| institution | Directory Open Access Journal |
| issn | 2008-7306 |
| language | fas |
| last_indexed | 2024-12-20T20:13:49Z |
| publishDate | 2010-08-01 |
| publisher | Ferdowsi University of Mashhad |
| record_format | Article |
| series | Journal of Economic Geology |
| spelling | doaj.art-1c15ce34ec4a4bbbbfc23ae3e6bfc4252022-12-21T19:27:45ZfasFerdowsi University of MashhadJournal of Economic Geology2008-73062010-08-0121617510.22067/econg.v2i1.3686Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, ArakRobabeh Jafari0Moussa Noghreyan1Mohammad Ali Mackizadeh2Javad Ghanei Ardekanei3Department of Geology, Faculty of Sciences, University of Isfahan, Isfahan, IranDepartment of Geology, Faculty of Sciences, University of Isfahan, Isfahan, IranDepartment of Geology, Faculty of Sciences, University of Isfahan, Isfahan, IranDepartment of Geology, Payame Noor University, IranNezam-Abad area is located in southwest of Shazand (Arak) which is a part of Sanandaj-Sirjan zone. Major intrusive rocks of Nezam-Abad are quartz diorite and minor amount of granodiorite. Leucogranitic, pegmatite dykes and quartz-tourmaline veins were intruded the quartz diorite. Quartz diorites are mainly composed of plagioclase, hornblende, biotite, quartz and pyroxene as major minerals. Major minerals of leucogranite are microcline, orthoclase, albite, quartz, biotite and muscovite. Accessory minerals consist of apatite, zircon, sphene, epidote, allanite, tourmaline and opaque. The presence of hydrous minerals like hornblende and biotite in these rocks indicate that the corresponding magma initially contained >3 wt% H2O (wet magma). The occurrences of garnet and andalusite minerals suggest assimilation process. Primary textures in these rocks are granular, granophyre, and poikilitic. Secondary textures are perthite, myrmekite, sericitization, chloritization and kaolinitization. Later hydrothermal activities and tectonic strains are factors for presence of perthite texture in leucogranite. K amount for sericitization of feldspars come from the K-feldspars and chloritization of biotite. Transformation of biotite to muscovite indicates the act of K rich fluid in later stages. On the basis of chemical analysis on the intrusive rocks, it is shown that the magma was calc-alkaline, metaluminous-peraluminous and medium-K to high-K. Study of major elements in Harker diagrams indicates Al2O3, FeO, Fe2O3 and CaO decrease with increasing of SiO2 and K2O and Na2O increase indicating that fractional crystallization may have played an important role in the formation of granitoid rocks from Nezam-Abad.https://econg.um.ac.ir/index.php/econg/article/view/3686petrographyquartzdiorteleucogranitetourmalineNezam AbadArak |
| spellingShingle | Robabeh Jafari Moussa Noghreyan Mohammad Ali Mackizadeh Javad Ghanei Ardekanei Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak Journal of Economic Geology petrography quartzdiorte leucogranite tourmaline Nezam Abad Arak |
| title | Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak |
| title_full | Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak |
| title_fullStr | Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak |
| title_full_unstemmed | Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak |
| title_short | Petrography and geochemical study of Nezam-Abad area, Southwest of Shazand, Arak |
| title_sort | petrography and geochemical study of nezam abad area southwest of shazand arak |
| topic | petrography quartzdiorte leucogranite tourmaline Nezam Abad Arak |
| url | https://econg.um.ac.ir/index.php/econg/article/view/3686 |
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