تعیین پراکندگی اندازه و شکل بلورهای پلاژیوکلاز و مدت اقامت آنها در توده آذرین‌ چاه موسی (جنوب شاهرود)

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه پترولوژی و زمین‌شناسی اقتصادی، دانشکده علوم زمین، دانشگاه صنعتی شاهرود، شاهرود، ایران

چکیده

به دلیل اهمیت بلورهای پلاژیوکلاز در بازسازی فرایندهای سردشدن ماگما، پراکندگی اندازه و شکل بلوری این کانی­ها با استفاده از روش کمی پراکندگی اندازه ‌بلور (CSD) برای توده نیمه عمیق چاه موسی (شمال غرب ترود، استان سمنان) بررسی شد. شیب نمودارهای CSD، لگاریتم طبیعی توزیع پراکندگی چگالی تراکمی بلور (n) نسبت به طول بلور (L)، نشان می­دهد که درشت بلور‌های پلاژیوکلاز در این توده آذرین دارای نرخ هسته‌بندی 8-10×4/1 تا mm/s 9-10×27/9 بوده و در گستره زمانی 62/118 تا 7/630 سال در آشیانه ماگمایی رشد کرده‌اند. مدت اقامت محاسبه شده با ماهیت نیمه­عمیق نمونه­های مورد بررسی همخوانی دارد. همچنین، نمودارهای CSD فرایند آمیختگی جمعیت بلوری را نشان می‌دهند و بیانگر دوره‌های متعدد تبلور در محفظه‌های ماگمایی متفاوت است. نتایج حضور دست کم دو جمعیت بلوری را نشان میدهند: درشت بلورهایی که طی سرد شدن مذاب تشکیل شده­اند و آنهایی که طی برداشته شدن فشار با سرعت هسته­بندی متفاوتی شکل گرفته­اند.  

کلیدواژه‌ها

عنوان مقاله [English]

Crystal size and shape distributions plagioclase and determining of crystal residence time in the Chah-Musa intrusion (South Shahrood)

نویسندگان [English]

  • Hosseini
  • Sheibi
Department of Petrology and Economic Geology, Faculty of Earth Sciences, Shahrood University of Technology
چکیده [English]

Considering the importance of plagioclase in reconstructing magma cooling processes, the size and shape distribution of this mineral is investigated for Chah - Musa sub-volcanic intrusion (NW Toroud- Semnan Province). The slopes of CSD diagrams, the natural logarithm of the density of the crystalline density (n) against the length of the crystal (L), show plagioclase phenocrysts available in this intrusion have been grown with rates of 1.4×10-8 to 9.27×10-9 mms-1, in time limited 118.62 to 630.7 years. The calculated residence time of magma in Chah-Musa intrusion coincides with sub-volcanic nature of the studied samples. Crystal size distribution diagrams suggest presence of two populations of crystals that formed during the anneal period as well as during decompression, associated with separate nucleation regimes.

کلیدواژه‌ها [English]

  • Crystal size distribution (CSD)
  • plagioclase
  • Chah – Musa

مراجع

  1. [1] Lofgren G. E., "The effect of nucleation on the basaltic textures. Abstracts with programs, Geolgical Society of America, 11 (1979)467-468.
  2. [1] Lofgren G. E., "The effect of nucleation on the basaltic textures. Abstracts with programs, Geolgical Society of America, 11 (1979)467-468.
  3. [2] Higgins M. D., Roberge J., "Three magmatic components in the 1973 eruption of Eldfell volcano, Iceland: Evidence from plagioclase crystal size distribution (CSD) and geochemistry, Journal of Volcanology and Geothermal Research, 161 (2007) 247-260. [DOI:10.1016/j.jvolgeores.2006.12.002]
  4. [2] Higgins M. D., Roberge J., "Three magmatic components in the 1973 eruption of Eldfell volcano, Iceland: Evidence from plagioclase crystal size distribution (CSD) and geochemistry, Journal of Volcanology and Geothermal Research, 161 (2007) 247-260. [DOI:10.1016/j.jvolgeores.2006.12.002]
  5. [3] Marsh B., "Crystal size distribution (CSD) in rocks and the kinetics and dynamics of crystallization I", Theory Contributions to Mineralogy and Petrology, 99 (1988) 277-291. [DOI:10.1007/BF00375362]
  6. [3] Marsh B., "Crystal size distribution (CSD) in rocks and the kinetics and dynamics of crystallization I", Theory Contributions to Mineralogy and Petrology, 99 (1988) 277-291. [DOI:10.1007/BF00375362]
  7. [4] Cashman K.V., Marsh B.D., "Crystal size distribution (CSD) in rocks and the kinetics and dynamics of crystallization II. Makaopuhi Lava Lake", Contributions to Mineralogy and Petrology, 92 (1988) 292-305. [DOI:10.1007/BF00375363]
  8. [4] Cashman K.V., Marsh B.D., "Crystal size distribution (CSD) in rocks and the kinetics and dynamics of crystallization II. Makaopuhi Lava Lake", Contributions to Mineralogy and Petrology, 92 (1988) 292-305. [DOI:10.1007/BF00375363]
  9. [5] Higgins M.D., "Quantitative textural measurement in igneous and metamorphic petrology, Cambridge University Press, United States of America (2006). [DOI:10.1017/CBO9780511535574]
  10. [5] Higgins M.D., "Quantitative textural measurement in igneous and metamorphic petrology, Cambridge University Press, United States of America (2006). [DOI:10.1017/CBO9780511535574]
  11. [6] Driscoll B.O., Donaldson C.H. Troll, V.R. Jerram, D.A. Emeleus, H., "An origin for harrisitic and granular olivine in the rum layered suite, NW Scotland: a crystal size distribution study", Journal of Petrology, 48 (2007) 253-270. [DOI:10.1093/petrology/egl059]
  12. [6] Driscoll B.O., Donaldson C.H. Troll, V.R. Jerram, D.A. Emeleus, H., "An origin for harrisitic and granular olivine in the rum layered suite, NW Scotland: a crystal size distribution study", Journal of Petrology, 48 (2007) 253-270. [DOI:10.1093/petrology/egl059]
  13. [7] Masoudi F., Ghorbani M., Rahimzadeh B., 2009 , "Study of physical conditions and magmatic evolution of volcanic rocks in East Of Qazvin", Iranian Journal Of Geology 3, Number 11, 67 - 75.
  14. [7] Masoudi F., Ghorbani M., Rahimzadeh B., 2009 , "Study of physical conditions and magmatic evolution of volcanic rocks in East Of Qazvin", Iranian Journal Of Geology 3, Number 11, 67 - 75.
  15. [8] Raeisi D., Dargahi S., Moeinzadeh H., Arvin M., "Using Numerical Modeling for Estimation of Rate of Nucleation and Growth Time of Plagioclase Microlites from Quaternary Gandom Beriyan Basaltic Flows", NE of Kerman. Journal of Geoscience, 22(85) (2012) 199-204. doi: 10.22071/gsj.2012.54042
  16. [8] Raeisi D., Dargahi S., Moeinzadeh H., Arvin M., "Using Numerical Modeling for Estimation of Rate of Nucleation and Growth Time of Plagioclase Microlites from Quaternary Gandom Beriyan Basaltic Flows", NE of Kerman. Journal of Geoscience, 22(85) (2012) 199-204. doi: 10.22071/gsj.2012.54042
  17. [9] Pourkhorsandi H., Mirnejad H., Raiesi D., Hassanzadeh J., "Crystal size and shape distribution systematics of plagioclase and the determination of crystal residence times in the micromonzogabbros of Qisir Dagh, SE of Sabalan volcano (NW Iran), Geologica Carpathica, 66, 4 (2015) 257-268 doi: 10.1515/geoca-2015-0024. [DOI:10.1515/geoca-2015-0024]
  18. [9] Pourkhorsandi H., Mirnejad H., Raiesi D., Hassanzadeh J., "Crystal size and shape distribution systematics of plagioclase and the determination of crystal residence times in the micromonzogabbros of Qisir Dagh, SE of Sabalan volcano (NW Iran), Geologica Carpathica, 66, 4 (2015) 257-268 doi: 10.1515/geoca-2015-0024. [DOI:10.1515/geoca-2015-0024]
  19. [10] Zadsaleh M., Pourkhorsandi H., "Quantitative textural investigation of trachyandesites of Damavand volcano (N Iran): Insights into the magmatic processes", Journal of African earth sciences120 (2016) 238-247. [DOI:10.1016/j.jafrearsci.2016.05.011]
  20. [10] Zadsaleh M., Pourkhorsandi H., "Quantitative textural investigation of trachyandesites of Damavand volcano (N Iran): Insights into the magmatic processes", Journal of African earth sciences120 (2016) 238-247. [DOI:10.1016/j.jafrearsci.2016.05.011]
  21. [11] Ayati F., Mahdevari S., "Investigation of crystal size distribution in igneous rocks: Guide to the magma evolution in magma chambers", Iranian Journal of Crystallography and Mineralogy 18 (3) (2010) 419-430.
  22. [11] Ayati F., Mahdevari S., "Investigation of crystal size distribution in igneous rocks: Guide to the magma evolution in magma chambers", Iranian Journal of Crystallography and Mineralogy 18 (3) (2010) 419-430.
  23. [12] Imamjome A., Rastad E., Bouzari F., Rashidnezhad N., "An introduction to individual disseminated veinlet and vein mineralization system of Cu (Pb-Zn) in the Chah Musa and Gholle [1] Kaftaran mining district, eastern part of the Troud-Chah Shirin magmatic arc, Geosciences, Scientific Quarterly Journal, 18, 112-125 (in Persian) (2009).
  24. [12] Imamjome A., Rastad E., Bouzari F., Rashidnezhad N., "An introduction to individual disseminated veinlet and vein mineralization system of Cu (Pb-Zn) in the Chah Musa and Gholle [1] Kaftaran mining district, eastern part of the Troud-Chah Shirin magmatic arc, Geosciences, Scientific Quarterly Journal, 18, 112-125 (in Persian) (2009).
  25. [13] Seifivand A., Sheibi, "Ballooning emplacement and alteration of the Chah-Musa subvolcanic intrusion (NE Iran) inferred from magnetic susceptibility and fabric", Geological Magazine (2019) doi:org/10.1017/S0016756819001158. [DOI:10.1017/S0016756819001158]
  26. [13] Seifivand A., Sheibi, "Ballooning emplacement and alteration of the Chah-Musa subvolcanic intrusion (NE Iran) inferred from magnetic susceptibility and fabric", Geological Magazine (2019) doi:org/10.1017/S0016756819001158. [DOI:10.1017/S0016756819001158]
  27. [14] Higgins M.D., "Measurement of crystal size distributions", American Mineralogist 85 (2000) 1105- 1116. [DOI:10.2138/am-2000-8-901]
  28. [14] Higgins M.D., "Measurement of crystal size distributions", American Mineralogist 85 (2000) 1105- 1116. [DOI:10.2138/am-2000-8-901]
  29. [15] Bruger C.R., Hammer J.E., "Crystal size distribution analysis of plagioclase in experimentally decompressed hydrous rhyodasite magma", Earth and Planetary Science Letters, 300 (2010) 246-254. [DOI:10.1016/j.epsl.2010.09.046]
  30. [15] Bruger C.R., Hammer J.E., "Crystal size distribution analysis of plagioclase in experimentally decompressed hydrous rhyodasite magma", Earth and Planetary Science Letters, 300 (2010) 246-254. [DOI:10.1016/j.epsl.2010.09.046]
  31. [16] Marsh B. D., "On the interpretation of crystal size distribution in magmatic systems", Journal of Petrology, 39 (1998) 553-599. [DOI:10.1093/petroj/39.4.553]
  32. [16] Marsh B. D., "On the interpretation of crystal size distribution in magmatic systems", Journal of Petrology, 39 (1998) 553-599. [DOI:10.1093/petroj/39.4.553]
  33. [17] Zingg T., "Contribution to the gravel analysis (Beitrag zur Schotteranalyse)", Schweizerische Mineralogische und Petrographische Mitteilungen, 15 (1998) 38-140.
  34. [17] Zingg T., "Contribution to the gravel analysis (Beitrag zur Schotteranalyse)", Schweizerische Mineralogische und Petrographische Mitteilungen, 15 (1998) 38-140.
  35. [18] Zadsaleh M., Pourkhorsandi H., "Quantitative textural investigation of trachyandesites of Damavand volcano (N Iran): insights into the magmatic processes", Journal of African Earth Sciences, 120 (2016) 238-247. [DOI:10.1016/j.jafrearsci.2016.05.011]
  36. [18] Zadsaleh M., Pourkhorsandi H., "Quantitative textural investigation of trachyandesites of Damavand volcano (N Iran): insights into the magmatic processes", Journal of African Earth Sciences, 120 (2016) 238-247. [DOI:10.1016/j.jafrearsci.2016.05.011]
  37. [19] Vinet N., Higgins M. D., "Magma Solidification Processes beneath Kilauea volcano, Hawaii: A Quantitative Textural and Geochemical Study of the 1969-1974 Mauna Ulu Lavas", Journal of Petrology, 6 (2010) 1297-1332. [DOI:10.1093/petrology/egq020]
  38. [19] Vinet N., Higgins M. D., "Magma Solidification Processes beneath Kilauea volcano, Hawaii: A Quantitative Textural and Geochemical Study of the 1969-1974 Mauna Ulu Lavas", Journal of Petrology, 6 (2010) 1297-1332. [DOI:10.1093/petrology/egq020]
مجله بلورشناسی و کانی شناسی ایران
دوره 29، شماره 1 - شماره پیاپی 81
فروردین 1400
صفحه 197-206

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سابقه مقاله

  • تاریخ دریافت: 26 اسفند 1398
  • تاریخ بازنگری: 02 اردیبهشت 1399
  • تاریخ پذیرش: 01 مرداد 1399

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