Volume 26, Issue 2 (7-2018)                   www.ijcm.ir 2018, 26(2): 339-354 | Back to browse issues page


XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Mineral chemistry of clinopyroxene in the Eocene basaltic rocks of the Gardaneh Ahovan area, NE Semnan. www.ijcm.ir. 2018; 26 (2) :339-354
URL: http://ijcm.ir/article-1-1102-en.html
Abstract:   (295 Views)
Eocene volcanic and volcano- sedimentary rocks cover a large area in the Gardaneh Ahovan northeast of Semnan. These rocks comprise mainly of basalt, andesite, trachyandesite, rhyolite and dacite with hyalo porphyry, porphyry and glomeroporphyry textures. The basaltic rocks are composed of plagioclase and clinopyroxene phenocrysts. Sericite, kaolinite, calcite and chlorite also form the secondary minerals in these rocks. The size of the clinopyroxenes of these rocks range from fine to medium and their compositions include iron-magnesium-calcium type and plot in the diopside field. Medium-size clinopyroxenes show reverse zoning and compositional changes so the middle zone (btween core and rim) is depleted in Fe, Al and Ti whereas enriched in the Mg, Ca and Si. The determination diagrams of the magmatic series and tectonic environments, based on the chemical composition of clinopyroxenes, suggest that they are crystallized from alkaline to sub-alkaline magma, contianing 2-5% water and high oxygen fugacity. Thermo-barometery calculations also show that these clinopyroxenes were crystallized in pressures of ~1 kbar and temperatures of 1110-1230 °C.
Full-Text [PDF 122 kb]   (115 Downloads)    
Type of Study: Research | Subject: Special
Received: 2018/07/7 | Accepted: 2018/07/7 | Published: 2018/07/7

References
1. [1] Etesami S., "Petrology of the Eocene volcanic rocks in the southern of Ahovan, E Semnan". M.Sc. Thesis, Research Institute for Earth Sciences, Geological Survey of Iran (2012) 143Pages.
2. [2] Mohseni S., "Petrology, Geochemistry and mineralization potential of igneous rocks of NE Semnan", M.Sc. Thesis, Faculty of Earth Sciences, Kharazmi University (2002) 140Pages.
3. [3] Shahosseni E., "Petrology, geochemistry and mineralization potential of igneous rocks of north and northeast of Semnan", M.Sc. Thesis, Faculty of Geosciences, Shahrood University OF Technology (2007) 165Pages.
4. [4] Khorasani E., "Investigation of deformation of Mesozoic and Cenozoic rock units in northeast of Semnan (North of Ahovan)", M.Sc. Thesis, Faculty of Geosciences, Shahrood University OF Technology (2014) 166Pages.
5. [5] Sadeghian M., Mirbagheri S.R., "Narkan Geological Quadrangle Map 1:25000", Geological Survey of Iran, Tehran (2012).
6. [6] Papazzoni C.A., Sirotti A., "Nummulite biostratigraphy at the Middle/Upper Eocene boundary in the Northern Mediterranean area", Rivista Italiana di Paleontologiae Stratigrafia 101 (1995) 63-80.
7. [7] Nabavi M.H, "Semnan Geological Quadrangle Map 1:100000", Geological Survey of Iran, Tehran (1987).
8. [8] Alavui-Nahini M., Hammedi A.R., "Jam Geological Quadrangle Map 1:100000", Geological Survey of Iran, Tehran (1997).
9. [9] Kretz R., "Symbols for rock-forming minerals", American Mineralogist, 68 (1983) 277-279.
10. [10] Putirka K. D., "Thermometers and barometers for volcanic systems", Reviews in Mineralogy and Geochemistry", 69 (2008) 61-120. [DOI:10.2138/rmg.2008.69.3]
11. [11] Nimis P., "A clinopyroxene geobarometer for basaltic systems based on crystals-structure modeling", Contribution to Mineralogy and Petrology 121 (1995) 115-125. [DOI:10.1007/s004100050093]
12. [12] Shelley D., "Igneous and Metamorphic rocks under the microscope", Chapman and hall (1993) 445.
13. [13] Morimoto N.,"Nomenclature of pyroxenes", Fortschr mineral 66 (1988) 237-252.
14. [14] Deer W. A., Howie R. A., Zussman J.,"Single-chain silicates (Vol. 2)", London: Longman (1978).
15. [15] Kress V. C., Carmichael I. S. E., "The compressibility of silicate liquids containing Fe2O3 and the effect of composition, temperature, oxygen fugacity and pressure on their redox states. Contrib. Mineral", Petrol. 108 (1991) 82–92. [DOI:10.1007/BF00307328]
16. [16] Kilinc A., Carmichael I. S. E., Rivers M. L., Sack R. O., "The ferric-ferrous ratio of natural silicate liquids equilibrated in air", Contrib. Mineral. Petrol. 83 (1983) 136–140. [DOI:10.1007/BF00373086]
17. [17] Moretti R., "Polymerisation, basicity, oxidation state and their role in ionic modelling of silicate melts", Annals of Geophysics (2005).
18. [18] Botcharnikov R. E., Koepke J., Holtz F., McCammon, C., Wilke M., "The effect of water activity on the oxidation and structural state oxidation of Fe in a ferro-basaltic melt", Geochimica Cosmochimica Acta 69 (2005) 5071–5085. [DOI:10.1016/j.gca.2005.04.023]
19. [19] Schweitzer E. L., Papike J. J., Bence A. E., "Statitical analysis of clinopyroxenes from deep- sea basalts", American Mineralogist 64 (1979) 501-513.
20. [20] Lindsley D.H., "Pyroxene thermometry", American Mineralogist, 68 (1983) 477-493.
21. [21] Le Base M. J., "The role of aluminum in igneous clinopyroxenes with relation to their Parentage", American Journal of Science 260 (1962) 267-288. [DOI:10.2475/ajs.260.4.267]
22. [22] Helz R. T., "Phase relations of basalts in their melting range at PH2O= 5 kb as a function of oxygen fugacity", Journal of Petrolology 17 (1973) 139-193. [DOI:10.1093/petrology/17.2.139]
23. [23] Soesoo A.," A multivariate statistical analysis of clinopyroxene composition: empirical coordinates for the crystallisation PT- estimations", Geological Society of Sweden (Geologiska Foreningen) 119 (1997) 55-60. [DOI:10.1080/11035899709546454]
24. [24] Baker D. R., David H. E "Compositions of anhydrous and hydrous melts coexisting with plagioclase, augite, and olivine or low-Ca pyroxene from 1 atm to 8 kbar: Application to the Aleutian volcanic center of Atka", American Mineralogist 72 (1987) 12-28.
25. [25] 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 Reserch 161 (2007) 247-260.
26. [26] Leterrier J., Maurry R. C., Thonon P., Girard D., Marchal M., "Clinopyroxene composition as a method of identification of the magmatic affinites of paleo-volcanic series", Earth and Planetary Science Letters 59 (1982) 139-154. [DOI:10.1016/0012-821X(82)90122-4]
27. [27] Nisbet E. G., Pearce J.A., "Clinopyroxene composition in mafic lavas from different tectonic settings", Contributions to Mineralogy and Petrology 63 (1977) 149–160. [DOI:10.1007/BF00398776]
28. [28] Beccaluva L., Macciotta G., Piccardo G. B. Zeda O., "Clinopyroxene composition of ophiolite basalts as petrogenetic indicator", Chemical Geology, 77 (1989) 165-182. [DOI:10.1016/0009-2541(89)90073-9]
29. [29] Blatt H., Tracy R., Owens B., "Petrology: igneous, sedimentary and metamorphic", Macmillan (2006).
30. [30] Mullaei H., "Mineralogy Atlas, Sokhan Gostar and Research Deputy of Islamic Azad University of Mashhad Publishing", (2006) 352 Pages.
31. [31] Deer W.A., Howie A., Zussman J., "An interduction to the rock – formingminerals", 17th ed.,) 1986 (Longman Ltd, 528P

Add your comments about this article : Your username or Email:
CAPTCHA code

© 2018 All Rights Reserved | Iranian Journal of Crystallography and Mineralogy

Designed & Developed by : Yektaweb