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References [1] Batanova, V.G., Sobolev, A.V., (2000). Compositional heterogeneity in subduction related mantle peridotites, Troodos massif, Cyprus. Geology, 28, 55-58. [2] Bortolotti V., (2012). Ophiolites: their first steps. Rend. Online Soc. Geol. It., 21, 299. [3] Büchl, A., Brügman, G., Batanova, V.G. (2004). Formation of podiform chromitite deposits: implications from PGE abundances and Os isotopic compositions of chromites from the Troodos complex, Cyprus. Chemical Geology, 208, 217--232. [4] Dilek Y., (2003). Ophiolite concept and its evolution. Geological

., MacLeod, C.J., Maeda, J., Mason, O.U., McCaig, A.M., Michibayashi, K., Morris, A., Nakagawa, T., Nozaka, T., Rosner, M., Searle, R.C., Suhr, G., Tominaga, M., von der Handt, A., Yamasaki, T. & Zhao, X., 2011. Drilling constraints on lithospheric accretion and evolution at Atlantis Massif, Mid-Atlantic Ridge 30°N. Journal of Geophysical Research 116, B07103. Bodinier, J.-L. & Godard, M. 2003. Orogenic, Ophiolitic and Abyssal Peridotites , [In:] R.W. Carlson (Ed.): Treatise on Geochemistry. Vol. 2: The Mantle and Core. Elsevier, Amsterdam, 103–170. Bonatti, E., Peyve

”, Geological Survey of Pakistan, Quetta, Vol. 181, Pp. 192, 1979. [22] Ali, “Petrology And Major Element Geochemistry Of Volcanic Rocks Beneath The Khanozai Ophiolite, Balochistan, Pakistan”, Bahria University Research Journal of Earth Sciences, Vol. 4(1), Pp. 40-45, 2019. [23] Haq, “Petrology And Major Element Geochemistry Of Mantle RocksFrom Khanozai Ophiolite, Northern Balochistan, Pakistan”, Bahria University Research Journal of Earth Sciences, Vol. 4(1), Pp. 26-32, 2019. [24] H. Ullah, and A. Khan, “Petrology and geochemistry of chromitite and peridotite from khanozai

Abstract

The Eocene nephelinite from Księginki quarry (SW Poland) contains five types of clinopyroxene phenocrysts varying by texture and chemical composition. Type I phenocrysts are formed of Mg-rich (mg# = 0.93–0.88) homogenous cores, patchy mantle and zoned rims. Abundant type II is less magnesian (mg# = 0.65–0.88) and consists of spongy or spongy-patchy core surrounded by zoned rims, whilst in type III (mg# = 0.69–0.84), the cores are massive but patchy. The mg# of cores of type IV phenocrysts is slightly lower than that of type I (0.79–0.89), but its cores are either massive or patchy. Type V is very scarce and consist of relatively Mg-poor (mg# = 0.75–0.77) core enveloped by nonpatchy, sometimes zoned mantle and zoned outer rim. Chemical composition of type I and type IV cores suggests that they are xenocrysts introduced into the nephelinite from disintegrated peridotite and clinopyroxenitic xenoliths, respectively. Type V is also of xenocrystic nature, but its source rock was significantly more evolved than mantlederived ones. Types II and III are possibly cognates from the host nephelinite or a melt related to the nephelinite. All the types of phenocrysts suffered from disequilibrium with the nephelinitic (or proto-nephelinitic) melt or dissolution during adiabatic uplift. Linear variation in chemical composition of phenocrysts of Księginki nephelinite suggests its evolution because of fractional crystallisation, without significant influence of other differentiation processes.

Abstract

The Zhob Ophiolite is divided into three detached blocks including the Omzha block. The Omzha block is mapped and divided into lithological units such as ultramafic rock, mafic-felsic rock, and volcanic–volcaniclastic–pelagic rocks. These units are quite deformed and mixed up and are associated with one another by thrust faults. Petrography and geochemistry divide them into gabbro, diorite, plagiogranite, pheno-tephrite and trachy-andesite basalt, trachy basalt, chert, limestone, and mudstone. The ultramafic rocks are dominantly serpentinized harzburgite, dunite, and a minor lherzolite. Petrography of peridotite shows that it may be depleted in nature and may have residual after processes such as partial melting and the melt-rock reaction of a lherzolitic source. The gabbroic rocks are less well-developed and highly deformed. They are cross-cut by diorite, plagiogranite and anorthosite’ intrusions. The gabbro may be the plutonic section of Omzha block’ crust while the intermediate-felsic igneous rocks may have formed by the anataxis of crustal gabbro. The volcanic–volcaniclastic–pelagic rocks unit may be corrected with Bagh complex found underneath the Muslim Bagh Ophiolite. The metamorphic sole rocks of Omzha block are highly deformed and dismembered are comprising of metamorphic facies such as amphibolite, quartz-mica schist, and greenschist.

evolution for a garnet peridotite lens with sub-Baltic Shield affinity within the Seve Nappe Complex of Jämtland, Sweden, Central Scandinavian Caledonides. Journal of Petrology , 45, 415–437. DOI: 10.1093/petrology/egg088. Bucher-Nurminen, K. (1982). Mechanism of mineral reactions inferred from textures of impure dolomitic marbles from East Greenland. Journal of Petrology , 23, 325–343. DOI: 10.1093/petrology/23.3.325. Chabu, M. & Baulège, J. (1992). Barian feldspar and muscovite from Kingushi Zn-Pb-Cu deposit, Shaba, Zaire. Canadian Mineralogist , 30, 1143

mainly in the area of the Kola Peninsula and Karelia. In some locations these rocks reach the age of about 3.7 Ga. They have a mosaic structure composed of migmatised granites with numerous intrusions and series of greenschists belts of an age between 3 and 2.4 Ga ( Mitrofanov, 2000 ; Bayanova, 2004 ; Bayanova et al ., 2010 ; Pozhylienko et al ., 2002 ). Layered intrusions are exposed in different locations of the crystalline Carton of the Baltic Shield, including the Kola Peninsula. These intrusions are predominantly basic and ultrabasic, composed of peridotites

, Matter J. In situ carbonation of peridotite for CO 2 storage. Proc National Acad Sci USA. 2008;105:17295-17300. DOI: 10.1073/pnas.0805794105. [20] Schuiling RD, Krijgsman P. Enhanced weathering: An effective and cheap tool to sequester CO 2 . Climate Change. 2006;74:349-354. DOI: 10.1007/s10584-005-3485-y. [21] Renforth P. The potential of enhanced weathering in the UK. Int J Greenhouse Gas Control. 2012;10:229-243. DOI: 10.1016/j.ijggc.2012.06.011. [22] Stępniewski W, Pawłowska M. A Possibility to Reduce Methane Emission from Landfills by Its Oxidation in the Soil

, 155–181. Holland T.J.B. and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, 309–343. https://doi.org/10.1111/j.1525-1314.1998.00140.x De Hoog J.C.M., Janák M., Vrabec M. and Froitzheim N., 2009. Serpentinised peridotites from an ultrahigh- pressure terrane in the Pohorje Mts. (Eastern Alps, Slovenia): Geochemical constraints on petrogenesis and tectonic setting. Lithos, 109, 209–222. https://doi.org/10.1016/j.lithos.2008.05.006 Hurai V., Janák M. and Thomas R., 2010. Fluid

relief which determines a uniform way of functioning of the environments. The High Tatra Mountains are eroded in acidic granite which intruded in the Carboniferous period; Cuillin Hills are composed mainly of Tertian 14 ANNA JAKOMULSKA intrusions: intermediate gabbro and ultrabasic peridotites. In humid cli- mate granite weathers quickly producing round hills, but under climatic conditions prevailing in The Tatra Mountains it forms steep and rugged peaks. Gabbro and peridotites are extremely hard rocks and also form high and rugged peaks. Both valleys are