Mineralogical and petrological properties of feldspathoid rocks from SW Sarab, NW Iran

Abstract

The major syenitic bodies of Iran are spread on northwestern part, East Azerbaijan Province, which belong to late Eocene, early Oligocene magmatisem. Abbasabbad–Bashkand pluton is one of these intrusions, which is located as some minor and autonomous bodies in western side of the main Bozghush nepheline syenite pluton. Porphyritic, microgranular and porphyritic microgranular are common textures in the studied rocks. On the basis of modal classification, these rocks belong to pseudoleucite syenite, nepheline monzodiorite, analcime syenite and syenite types. The main mineral constituent of these rocks encompass K-feldspar, plagioclase, pseudoleucite, analcim and nepheline. Pyroxene, hornblende, biotite, olivine, apatite, and opaque  exist  as accessory minerals and seresite, chlorite, oralite, idengsite, iron oxides and clay minerals exist as secondary minerals. Results of X-ray analysis indicate the existence of analcime, natrolite, nepheline, barium-rich feldspar (Celsian) in these rocks. Based on clinopyroxenes mineral chemistry, the entire pyroxenes plotted in Ca-Mg and Fe pyroxenes region. The compound of pyroxene end members were changed between En40.75Fs9.40Wo43.98 and En43.23 Fs13.61Wo47.8, that indicate the existence of diopsidic augite clinopyroxenes in these rocks. Based on chemical classifications, the rocks are nepheline syenite, syenite and syenite-diorite. Agpaitic mineralogy index studies indicate studied rocks are classified as miascitic nepheline syenite. Magmatic series of the studied rocks are high potassium alkaline and shoshonitic.   Al bearing, ferromagnesian and opaque minerals are the main controlling agent of CaO, MgO, K2O and Al2O3 amount. K2O amount  increases as SiO2 increasing. Geochemical diagrams, spider diagrams and REE patterns of the studied rocks show that they are formed in an subduction-related tectonic setting. Distinct enrichment in Th, Ba, Rb, K and U probable depends on mantle metasomatism processes and/or continental crust mixing. Ta, Nb and Ti anomalies and metaluminous characteristics of investigated rocks in one hand, and Neotethys subduction occurrence in other hand, probably indicate subduction affects on enrichments of incompatible elements in mantle resources of the studied rocks.  

Keywords

References

[1] Alavi M., "Tectonic Map of the Middle East", 1:5000000. Geological Survey of Iran (1991).

]2[ نقشه زمین شناسی 1:100000 ترکمنچای- قره چمن، سازمان زمین شناسی کشور.

[3] Stocklin J., "Structural correlation of the Alpine ranges between Iran and Central Asia", Memoir Hors Service Society Geologique France, N.8 (1977) 333-353.

]4[ لطفی م.، "بررسی‌های زمین شناسی وپترولوژی منطقه شمال- شمال شرق میانه (آذربایجان خاوری)"، پایان نامه کارشناسی ارشد. دانشکده علوم طبیعی. دانشگاه تهران (1354).

[5] باباخانی ع.، "مطالعه پتروگرافی وژئوشیمی نفلین سینیتها و فنولیتهای شمال آذربایجان"، پایان نامه کارشناسی ارشد. دانشکده علوم طبیعی. دانشگاه تهران (1360).

[6] افتخارنژاد ج.، باباخانی ع.، حسین‌خان‌ناظر ن.، "عملیات اکتشافی تودهای نفلین سینیتی بزگوش- رزگاه به عنوان ماده اولیه آلومینا"، شیشه و سرامیک، سازمان زمین شناسی کشور (1367).

[7] باباخانی ع.، امینی آذر ر.، "گزارش عملیات اکتشافی بر روی توده نفلین سینیتی کلیبر به عنوان ماده اولیه تولید آلومینا، شیشه، سرامیک و سنگهای تزئینی و نما"، سازمان زمین شناسی کشور، شرکت توسعه علوم زمین (1373).

[8] اشرفی ن.، "بررسیهای پترولوژیکی و ژئوشیمیایی توده نفوذی رزگاه (سراب ـ آذربایجانشرقی)، شمالغرب ایران"، پایان نامه کارشناسی ارشد. دانشکده علوم طبیعی. دانشگاه تبریز. 97ص (1383).

[9] شهریار و.، "بررسیهای پترولوژی و پتروگرافی توده نفوذی بزقوش"، جنوب سراب. پایان نامه کارشناسی ارشد. دانشکده علوم طبیعی. دانشگاه تبریز. 107ص (1384).

[10] اشرفی ن.، "کانی شناسی، سنگ شناسی و ژئوشیمی فوئیدسینیت های آذربایجانشرقی، شمال غرب ایران". پایان نامه دکتری دانشگاه تبریز، دانشکده علوم طبیعی، 190 ص (1388).

[11] عبادی ل.، "پترولوژی و ژئوشیمی توده های آذرین فلدسپاتوئیددار غرب بزقوش (عباس آباد- باشکند)"، جنوب غرب سراب. پایان نامه کارشناسی ارشد. دانشکده علوم طبیعی. دانشگاه تبریز. 112ص (1386).

[12] Streckeisen A, Le Maitre RW. "A chemical approximation to the modal QAPF classification of the igneous rocks", Neues Jahrbuch für Mineralogie, Abhandlungen 136, (1979) 169–206.

[13] Morimoto N., Fabrise J., Ferguson A., Ginzburg I. V., Ross M., Seifert F. A., Zussman J., Aoki K., Gottardi G., "Nomenclature of pyroxene", Mineralogical Magazine 52 (1988) 535-555.

[14] Leterrier J., Maury R. C., Thonon P., Girard D., Marchal M., "Clinopyroxene composition as a method of identification of the magmatic affinities of paleo-volcanic series", Earth and Planetary Science Letters 59 (1982) 139-154.

[15] LeMaitre R. W., ed. "A classification of Geological sciences subcommision on the systematics of igneous rocks", Blackwell Scientific Publications, Oxford, Great Britain, 193 pp (1989).

[16] Irvine T. N., Baragar W. R., "Aguide to the chemical classification of the commn Volcanic Rocks", Canadian Journal of Earth Sciences. 8, p. 523- 546 (1971).

[17] Ussing N. V., "Geology of the country around Julianehaab Greenland.MeddrGronland", 38 (1912) 1-376.

[18] Sun S.S., McDonough W. F., "Chemical and isotopic systematic of oceanic basalts, implications for mantle composition and processes", Geological Society, London, Special Publications 42 (1) (1989) 313-345.

[19] Jung S., Hoffer E., Hoernes S., "Neo- Proterozoic rift- related syenites (North Damara Belt, Namibia): Geochemical and Nd-Sr-PB-O isotope constraints for mantle sources and petrogenesis", Lithos, 96 (2007) 415-435.

[20] Ying J., zhang H., Sun M., Tang Y., Zhou X., Liu X., "Petrology and geochemistry of Zijinshan alkaline intrusive complex in Shanxi Province", western North China Craton: Implication for magma mixing of different sources in an extensional regime. Lithos, 01566 (2007) 1-22.

[21] Soesoo A., "Fraction crystallization of mantle derived melt as a mechanism for some I-Type granite petrogenesis: An example from Iachlan fold belts", Australia. Journal of the Geological Society, London. Vol, 157 (2000) 135-149 pp.

[22] Edward C.M.H., Menzies M.A., Thirlwall M.F., Morrid J.D., Leeman W.P., Harmon R.S., "The transition to potassic alkaline volcanism in island arcs: the Ringgite-Beser Complex", East Java, Indonesia, Journal of Petrology, Vol. 35, No. 6, (1994) 12. p. 1557-1595.

[23] Ionov D.A., Hofmann A.W., "Nb-Ta rich mantle amphiboles and micas: implication for subduction-related metasomatic trace element fractionations", Earth Planet SciLett. 131 (1995) 341-356.

[24] Ying J., zhang H., Sun M., Tang Y., Zhou X., Liu X., "Petrology and geochemistry of Zijinshan alkaline intrusive complex in Shanxi Province", western North China Craton: Implication for magma mixing of different sources in an extensional regime. Lithos, 01566 (2007) 1-22.

[25] Ilbeyli N., Pearce J. A., Thirlwall J. G., Mitchell J. G., "Petrogenesis of collision- related plutonics in Central Anatolia", Turkey. Lithos, 72 (2004) 163-182.

[26] Upadhyay D., Raith M. M., Mezger K., Hammerschmidt, "Mesoproterozoic rift- related alkaline magmatism at Elchuru", prakasam Alkaline Province, SE India, Lithos, 89 (2006) 447-477.

[27] Jung S., Hoffer E., Hoernes S., "Neo- Proterozoic rift- related syenites (North Damara Belt", Namibia): Geochemical and Nd-Sr-PB-O isotope constraints for mantle sources and petrogenesis. Lithos, 96 (2007) 415-435.

[28] Chen B., Jahn B. M., Arakawa Y., Zhai M. G., "Petrogenesis of the Mesozoicintrusive complexes from the southern TaihangOrogen, North China Craton:elemental and Sr-Nd-Pb isotopic constraints", Contributions to Mineralogy and Petrology. 148 (2004) 489-501.

[29] Rogers N. W., Hawkesworth C. J., Parker R. J., Marsh J. S., "The geochemistry of potassic lavas from Vulsini", central Italy and implications for mantle enrichment processes beneath the Roman region. Contributions to Mineralogy and Petrology.90 (1985) 244-257.

[30] Nelson D. R., McCulloch M. T., "Enriched mantle components and mantle recycling of sediments. In: Ross", J. (Ed.), Kimberlites and related rocks. Vol 1.Their Composition, Occurrence, Origin and Emplacement. Geological Society of Australia Special Publication, vol. 14 (1989) pp. 560-570.

[31] Zhao J. X., Shiraishi K., Ellis D. J., Sheraton J. W., "Geochemical and isotopic studies of syenites from the Yamato Mountains", East Antarctica: implications for the origin of syenite magmas. Geochimicate Cosmochimica Acta 59 (1995) 1363-1382.

[32] Fisk M. R., Upton B. G. J., Ford C. E., "Geochemical and experimental study of thegenesis of magma of Re:union: Island, Indian Ocean", Journal of Geophysical Research .93 (1988) 4933-4950.

[33] Baker B. H., "Outline of the petrology of the Kenya Rift alkaline province. In:Fitton, G. G., Upton, B. G. J. (Eds.)", Alkaline Igneous Rocks. Geological SocietySpecial Publication, vol. 30, (1987) pp. 293-311.

[34] McDonough W. F., McCulloch M. T., Sun S. S., "Isotopic and geochemicalsystematic in Tertiary- Recent basalts from southeastern Australia and implicationsfor the evolution of the subcontinental lithosphere", Geochim. Cosmochim. Acta , 49 (1985) 2051-2067.

[35] Menzies M., "Alkaline rocks and their inclusions: a window on the Earths interior", Geological Society, London, Special Publications, v.30; p15-27.

[36] Muller D., Groves D.I., Potassic igneous rocks and associated Gold- Copper Mineralization.Secod Updated and Enlarged Edition, Springer (1997) 238 pp.

[37] Fowler M. B., "Elemental and O-Sr-Nd isotope geochemistry of the Glen Dessarysyenite", NW Scotland. Journal of the Geological Society 149 (1992) 209-220.

[38] Thirlwall M. F., Burnard P., "Pb-Sr-Nd isotope and chemical study of the origin of undersaturated and oversaturated shoshonitic magmas from the Borralan pluton", Assynt, NW Scotland. Journal of the Geological Society.147 (1990) 259-269.

[39] Thompson R. N., Fowler M.B., "Subduction-related shoshonitic and ultrapotassic magmatism: a study of Siluro-Ordovician syenites from the Scottish Caledonides", Contributions to Mineralogy and Petrology, 94 (1986) 507–22.

[40] Berberian M., King G.C.P., "Toward a paleogeography and tectonic evolution of Iran", Canadian Journal of Earth Science 18 (1981) 210–265.

[41] Peccerillo A., "Potassic and ultrapotassic rocks: Compositional characteristics", petrogenesis and geologic significance; IUGS Episods 15 (1992) 243–251.

Files

History

  • Receive Date: 02 July 2025
  • Revise Date: 04 February 2026
  • Accept Date: 02 July 2025

Share

How to cite

Statistics