Garmichay metapelites, NW Iran: whole rock chemistry, mineral chemistry, provenance and metamorphic conditions

Abstract :

In order to study the provenance and metamorphic conditions of the Garmichay metapelites located in Northern Miyaneh, NW Iran the whole rock chemistry of this assemblage is investigated. Petrofabric scrutinizes have revealed the syn-tectonic nature of cordierite porphyroblasts (regional metamorphism) in the metapelites. Besides, C' shear band structures are observed. Two regional metamorphic (RMP1, RMP2), one contact metamorphic (CMP) and two deformation (D1, D2) phases are identified. The major oxide geochemistry implies two sedimentary progenitors: shale and greywacke. Based on major, rare earth and trace elements (Ti, Ni, TiO2, Zr and K2O) the igneous source rock has had andesite to dacite/rhyodacite nature. The chemical index of alteration and weathering indexes (CIA, CIW) imply a medium degree of alteration in the igneous progenitor. The Garmichay metapelites, in comparison with the PAAS and UCC, are enriched in Cs, La and Ce and depleted in Sr, Nb and Ta. The representative samples in the compatibility diagrams lie inside the paragenetic triangles that imply their stable conditions. Finally, based on the standard pseudosections the temperature and pressure range of the highest degree paragenesis has been 535-635 °C and 1-3 kb, respectively.

References:

بهروزی، ا.، امینی آذر، ر.، عزتیان، ف.، امامی، م.، داوری، م.، هادوی، ف.، بغدادی، ا.، 1371. نقشه زمین شناسی سراب (1:10000). سازمان زمین شناسی ایران.
علوی تهرانی، ن.، لطفی م.، بوردت، پ.، سبزه¬ای، م.، بهروزی، ا.، حقی پور، ا.، عمیدی، م.، 1357. نفشه زمین شناسی میانه (1:250000). سازمان زمین شناسی ایران.
محامد، ا.، مؤید، م.، مجرد، م.، 1399. گرانیتهای تیپ S منطقه گرمی¬چای (شمالغرب ایران): شیمی سنگ کل، جایگاه زمین ساختی و ساز و کار تشکیل. مجله پترولوژی (در نوبت چاپ).
Ague, J. J. (1991) Evidence for major mass transfer and volume strain during regional metamorphism of Pelites. Geology 19: 855-858.
Bertoldi, C., Proyer, A., Schonberg, D. G., Behrens, H., Dachs, E. (2004) Comprehensive chemical analyses of naturalcordierites: implications for exchange Mechanisms. Lithos78: 389-409.
Bierlein, F. P. (1995) Rare-earth element geochemistry of clastic and chemical metasedimentary rocks associated with hydrothermal sulphide mineralisation in the Olary Block, South Australia. Chemical Geology 122: 77-98.
Boles, J. R. and Franks, S. G. (1979) Clay diagenesis inWilcox sandstones ofsouthwest Texas, implications of smectite diagenesis on sandstonecementation. Jornal of Sedimentary Petrology 49:55–70.
Bucher, K., and Frey, M. (1994) Petrogenesis of Metamorphic Rocks.Springer Verlay.
Bucher, K. and Grapes, R. (2011) Petrogenesis of metamorphic rocks. Springer-Verlag.
Condie, K.C. (1993) Chemical composition and evolution of theupper continental crust: contrasting results from surfacesamples and shales. Chemical Geology 104: 1–37.
Condie, K. C. )1997) Plate Tectonics and Crustal Evolution.4th edition.Butterworth-Heinemann.
Cullers, R.L., Bock, B. and Guidotti, C. (1997) Elementaldistributions and neodymium isotopic compositions of Silurian metasediments, western Maine, USA: Redistriburionof the rare earth elements. Geochim.Cosmochim. Acta,61:1847–1861.
Eftekharnejad, J. (1975) Brief history and structural development of Azarbaijan. Geological Survey of Iran. Internal Report 8p.
Elias, E. M. and Al-Jubory, Z. J. (2013) Provenance and tectonic setting of the metapelites deposits in the Bulfat Complex, NE-Iraq. Arab Journal of Geosciences 7(9): 3589-3598.
Fedo, C. M., Nesbitt, H. W. and Young, G. M. (1995) Unravelling the effects of potassium metasomatism in sedimentary rocks and paleosols, with impilications for paleoweathering conditions and provenance. Geology 23: 921-924.
Feng, R. and Kerrich, R. (1990) Geochemistry of fine-grained clastic sediments in theArchean Abitibi greenstone belt, Canada: implications for provenance andtectonic setting. Geochim.Cosmochim. Acta 54: 1061–1081.
Floyd, P. A., Winchester, J. A. and Park, R. G. (1989) Geochemistry and tectonic setting of Lewisian clastic metasediments from the early Proterozoic Lock Marie Group of Gairlock, Scottland. Precambrian Research 45: 203-214.
Garcia, D., Fonteilles, M. and Moutte, J. (1994) Sedimentary fractionations between Al,Ti, and Zr and the genesis of strongly peraluminous granites. Journal of Geology 102: 411-422.
Girty, G. H., Ridge, D. L., Knaack, C., Johnson, D. and Riyami RK A (1996) Provenance and depositional setting of Paleozoic chert and argillite, Sierra Nevada, California. Journal of Sedimentary Research 66: 107-118.
Hallberg, J. A. (1984) A geochemical aid to igneous rock identification in deply weathered terrain. Journalof Geology Exploration 20: 1-8.
Hawkesworth, C., Cawood, P.A. and Dhuime, B. (2019) Rates of generation and growth of the continental crust. Geoscience Frontiers 10: 165-173.
Henry, D.J. and Guidotti, C.V. (2002) Titanium in biotite from metapelitic rocks: Temperature effects, crystal-chemical controls and petrologic applications. American Mineralogist 87: 375-382.
Henry, D., Guidotti, C., Thomson, J. (2005) The Ti-SaturationSurface for Low-to-Medium Pressure Metapelitic Biotites:Implications for Geothermometry and Ti-SubstitutionMechanism. American Mineralogist 90: 316–328.
Herron, M. M. (1988)Geochemical classification of terrigenous sands and shales from core or log data. Journal ofSedimentary Petrology 58:820-829.
Holland, T. J. B. and Powell, R. (1998) An internally consistent thermodynamic dataset for phase of petrological interest. Journal of Metamorphic Geology 16: 309-343.
Ji, S., Saruwatari, K., Mainprice, D., Wirth, R., Xu, Z. and Xia, B. (2003) Microstructures, petrofabrics and seismic properties of ultra high-pressure eclogites from Sulu region, China: implications for rheology of subducted continental crust and origin of mantle reflections. Tectonophysics 370 (1-4): 49-76.
Johnson, T. M., Brown, M. and Solar G. A. (2003)Low–pressure subsolidus and suprasolidus phase equilibria in the MnNCKFMASHsystem: Constraints on conditions of regional metamorphism in western Maine, northernAppalachians88: 624-638.
Long, X., Sun, M., Yuan, C., Xiao, W. and Cai, K. (2008) Early Paleozoic sedimentary record of the Chinese ltai; Implications for its tectonic evolution. Sedimentary Geology 208: 88-100.
Mahar, E. M., Baker, J. M., Powell, R., Holland, T. J. B. and Howell, N. (1997) The effect of Mn on mineral stability in metapelites. Journal of Metamorphic Geology 15: 223-238.
Maynard, J.B., Valloni, R. and Yu, H. (1982) Composition of modern deep sea sands from arc-related basin. Geology Society of London. Special Publication 10: 551-561.
Mason, B. and Moore, C. B. (1982) Principle of Geochemistry. John Willey and Sons.Fourth Ed.
McLennan, S. M. and Taylor, S. R. (1991) Sedimentary rocks and crustal evolution: tectonic setting and secular trends. Journal of Geology 99: 1-21.
Meres, S. (2005) Major, trace element and REE geochemistry of metamorphosed sedimentaryrocks from the Malé Karpaty Mts. (Western Carpathians, Slovak Republic):Implications for sedimentary and metamorphic processes. Slovak Geological Magazine 11(2-3): 107-122.
Middelburg, J. J., Van Der Weijden, C. H. and Woittiez, J. R. W. (1988) Chemical processes affecting the mobility of major, minor and trace elements during weathering of granitic rocks. Chemical Geology 68: 253-273.
Nadimi, A. (2007) Evolution of the Central Iranian basement. Gondwana Research 12: 324-333.
Nesbitt, H. W. and Young, G. M. (1982) Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature 199:715–717
Nesbitt, H. W. and Young, G. M. (1984) Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations. Geochimica et Cosmochimica Acta 8: 1523-1534.
Nesbitt, H., Young, G. and Bosman, S. (2009) Major and trace element geochemistry and genesis of supracrustal rocks of the North Spirit Lake Greenstone belt, NW Ontario, Canada. Precambrian Research 174: 16–34.
Passchier, C.W. (1994) Mixing in flow perturbations: a model for developmentof mantled porphyroclasts in mylonites. Journal of Structural Geology 16:733-736.
Passchier, C. W. and Trouw, R. A. J. (2005) Microtectonics.2nd edition, Springer, 289 p.
Pattison, D. R. M. (1992) Stability of andalusite and sillimanite and the Al2SiO5 triple point: Constraints from the Ballachulish aureole, Scottland. Journal of Geology 100: 423-446.
Pattison, D. R. M. (2006) The fate of graphite in prograde metamorphism of pelites: An example from the Ballachulish aureole, Scotland. Lithos 88: 85-99.
Piazolo, S. and Passchier, C. W. (2002) Controls on lineation development in low to medium grade shear zones: a study from the Cap de Creus peninsula, NW Spain. Journal of Structural Geology 24: 25-44.
Potter, P. E., Maynard, J. B. and Depetris, P. J. (2005) Mud and Mudstones: Introduction and Overview.Heidelberg,Springer-Verlag.
Puchelt, H. (1972) Barium. Handbook of Geochemistry (Wedepohl, K. H. et al., eds.), 56B1–56O2, Springer, Berlin.
Puelles, P., Abalos, B., Gil Ibarguchi, J. I. and Fernandez-Armas, S. (2018) Petrofabric of forsterite marbles and related rocks from a low-pressure metamorphic terrain (Almadén de la Plata massif, Ossa-Morena Zone, SW Spain) and its kinematic interpretation. Journal of Structural Geology 117: 58-80.
Ramezani, J. and Tucker, R. D. (2003) The Saghand Region,Central Iran: U-Pb geochronology, petrogenesis and implicationsfor Gondwana Tectonics. American Journal ofScience 303: 622–665.
Roser, B. P.and Korsch, R. J. (1988) Provenance signatures of sandstone-mudstone suites determined using discriminantfunction analysis of major-element data. Chemical Geology 67:119–139.
Rollinson, H. (1993) Using geochemical data: evolution, presentation, interpretation. Longman Scientific and Technical, London.
Saki, A. (2010) Proto-Tethyan remnants in northwest Iran: geochemistryof the gneisses and metapelitic rocks.
GondwanaResearch 17(4): 704–714. Shahzeidi, M., Moayyed, M., Murata, M., Yui, T., Arai, Sh., Chene, F., Pirnia, T. and Ahmadian, J. (2016) Late Ediacaran crustal thickening in Iran: Geochemical and isotopic constraints from the ~550 Ma Mishu granitoids (northwest Iran) International Geology Review 59: 793-811.
Shaw, D. M. (1956) Geochemistry of pelitic rocks: Part III.Major elements and general geochemistry. Geology Society of American Bulltain 67: 919-934.
Spear, F. S. (1995) Metamorphic phase equilibria and pressure-temperature-time paths. Mineralogical Society of America, Monographs.
Stocklin, J. (1968a) Structural history and tectonics of Iran: a review. American Association of Petroleum Geological Bulletin 52(7): 1229–1258.
Symmesm G. H. and Ferry, J. M. (1992) The effect of whole-rock MnO content on the stability of garnet in pelitic schists during metamorphism. Journal of Metamorphic Geology 10: 221-238.
Taylor, S. R. and McLennan, S. M. (1985) The Continental Crust: Its Composition and Evolution. Blackwell, Oxford.
Toulkeridis, T., Clauer, N., Kroner, A., Reimer, T. and Todt, W. (1999) Characterization, provenance, and tectonic setting of Fig Tree graywackes from the Archean Barberton Greenstone Belt, South Africa. Sedimentary Geology 124: 113-129.
Vergara, M., Levi, B., Nystrom, J. O. and Cancino, A. (1995) Jurassic and Early Cretaceous island arc volcanism, extension, and subsidence in the Coat Range of central Chile. Geology Society of American Bulltain 107: 1427-1440.
Wei, C. J., Powell, R. and Clarke, G. L. (2004) Calculated phase equilibria for low- and medium-pressure metapelites in the KFMASH and KMnFMASH systems. Journal of Metamorphic Geology 22: 495-508.
Werner, C. D. (1987) Saxonian granulites-igneous or lithoigneous: a contribution to the geochemical diagnosis of theoriginal rock in high metamorphic complexes. Zfl Mitteilungen, 13: 221-250.
Whitney, D.L. and Evans, B.W. (2010) Abbreviations for namesof rock-forming minerals. American Mineralogist 95: 185–187.
Winchester, J. A. and Floyd, P. A. (1977) Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology 20: 325-343.
Young, G. and Nesbitt, H. (1998) Processes controlling the distribution of Ti and Al in weathering profiles, siliciclastic sediments and sedimentary rocks. Journal of Sedimentary research 68: 448-455.