Grew, Edward S.

Konilov, A. N.

Marquez, Nicholas

Yates, Martin G.

English

University of Maine

The University of MaineDigitalCommons@UMaineEarth Science Faculty Scholarship Earth Sciences6-1-1992Kornerupine from the Archean Kola Series atSholt-Yavr, Kola Peninsula, RussiaEdward S. GrewUniversity of Maine - Main, esgrew@maine.eduMartin G. YatesA. N. KonilovNicholas MarquezFollow this and additional works at: https://digitalcommons.library.umaine.edu/ers_facpubPart of the Earth Sciences CommonsThis Other is brought to you for free and open access by DigitalCommons@UMaine. It has been accepted for inclusion in Earth Science FacultyScholarship by an authorized administrator of DigitalCommons@UMaine. For more information, please contactum.library.technical.services@maine.edu.Repository CitationGrew, Edward S.; Yates, Martin G.; Konilov, A. N.; and Marquez, Nicholas, "Kornerupine from the Archean Kola Series at Sholt-Yavr,Kola Peninsula, Russia" (1992). Earth Science Faculty Scholarship. 162.https://digitalcommons.library.umaine.edu/ers_facpub/162SHORT COMMUNICAT IONS MINERALOGICAL MAGAZINE, JUNE 1992, VOL 56, PP. 247-251 Kornerupine from the Archaean Kola Series at Sholt-Yavr, Kola Peninsula, Russia KORNERUPINE, approximately (U],Mg,Fe)(Mg,- Fe,A1)9(Si,A1,B)5(O,OH,F)22, is a mineral of Mg-Al-rich rocks and magnesian metapelites in upper amphibolite- and granulite-facies rocks. It is reported from about 50-60 localities world- wide, including six in the former Soviet Union: Ukrainian shield (Kuryleva, 1960; Nalivkina, 1959), Aldan shield at the Usmun and Sutam Rivers (Kitsul et al., 1972; Grew et al., 1989, 1991), the Precambrian crystalline rocks of the southwestern Pamir Mountains at Darai Stazh and Mulvoj (Levitskiy et al., 1988, 1990; Grew et al., 1990a), and the Baltic shield in the Archaean Kola series of the Kola Peninsula (Fonarev et al., 1989). The term Kola series refers to units consisting predominantly of biotite- plagioclase + amphibole gneisses, amphibolite, and pelitic gneisses that are exposed over a wide area of the Kola Peninsula; metamorphic grade ranges from the amphibolite to the granulite facies (e.g. Nalivkina et al., 1984). In the present paper, we report chemical analyses and discuss the paragenesis of kornerupine first found by Fonarev et al. (1989), who reported the assemb- lage kornerupine + orthopyroxene + sapphirine + biotite, but provided no chemical or petrologic details. Kornerupine was found in core from a hole (no. 15) drilled in an iron ore deposit on the west shore of Lake Sholt-Yavr, 35 km south-southwest ofMurmansk. The hole at Sholt-Yavr penetrates alternating biotite-hornblende + garnet gneiss, garnet-biotite-cordierite gn iss, rare cordierite- orthopyroxene gneiss and pyroxene-magnetite quartzite of the Kola series and numerous bodies of microcline granite. Kornerupine occurs in a lens of aluminous sapphirine-bearing biotite schist at 154.2 m depth; lenses of similar biotite schist, but lacking kornerupine and orthopyr- oxene, are found at 152.7 and 221.5 depth. These lenses are 0.5-1.5 m thick. The rocks were affected by three events for which Fonarev et al. (1989; in press) calculated the following tempera- tures and pressures: 670 + 20~ 5.0 + 0.5 kbar; 575 _+ 20 ~ 3--4 kbar; and 500 + 20 ~ the first corresponding to the granutite facies. On the basis of Rb-Sr isochrons, Avakyan and Buya- kayte (1991) and Avakyan et al. (1991) have dated the beginning of metamorphic activity at 2880 _ 50 Ma and its conclusion at 2540 + 15 Ma. The kornerupine-bearing rock (15/154.2) con- sists dominantly of biotite, roughly equal amounts of orthopyroxene and sapphirine, and trace amounts of kornerupine, spinel, monazite, zircon, apatite, calcite, and ferroan magnesite. Grain size of the silicate phases is mostly 0.5-2 mm, with sapphirine somewhat finer and korner- upine somewhat coarser (to 2.5 mm). Biotite flakes are generally randomly oriented relative to one another. Sapphirine grains are equant to tabular and are commonly in aggregates. Spinel is found only as inclusions in sapphirine and is nearly opaque from fine magnetite inclusions, which probably contributed to the high Fe304 content in the microprobe analysis (Table 1). Kornerupine is pleochroic from colourless to pale blue in thin section. Its grains are typically subhedral to euhedral and contain inclusions of biotite and sapphirine. Kornerupine is locally in direct contact with orthopyroxene. Orthopyr- oxeue also encloses sapphirine, but less com- monly than kornerupine does. The equilibrium mineral assemblage is inferred to have been kornerupine + sapphirine + orthopyroxene +biotite, whereby kornerupine was the latest mineral to form, biotite and sapphirine the earliest. Spinel is interpreted as a relic armoured by sapphirine. Late low-temperature alteration affected sapphirine more than the other minerals: it is cut by seams of secondary minerals. Calcite locally fills cracks between cleavage foliae of biotite, whereas ferroan magnesite is associated with spinel. The biotite schist at 152.7 m (15/152.7) contains 248 SHORT COMMUNICAT IONS Table 1, Compositions of minerals in sample 15/154.2 from Sholt- Yavr, Kola Peninsula, USSR. Kornerupine Sapphir ine Ortho- Biotite Spinel l 2 pyroxene Electron Microprobe Analyses-wt % SiO2 28.98 29.36 13.82 51.21 38.20 b.d. TiO2 0.05 0.04 0.05 0.04 0.75 b.d. A1203 44.73 43.96 60.73 7.97 17.86 48.75 Cr203 b.d. b.d. b.d. b.d. b.d. 0.03 FeO 7.20 7.14 7.80 13.68 6.75 36.21 MnO 0.14 0.24 0.11 0.27 b.d. 0.22 MgO 17.02 16.42 17.61 26.58 19.93 11.49 CaO 0.07 0.07 0.04 0.15 0.02 b.d. ZnO b.d. b.d. b.d. b.d. b.d. 3.31 Na20 b.d. b.d. b.d. b.d. 0.37 b.d. K20 b.d. b.d. b.d. b.d. 10.08 b.d. Ion Microprobe Analysis-wt % Li20 0.03 0.03 0 .004 b.d. 0 .002 BeO b.d. 0.001 b.d. b.d. b.d. B203 1.32 1.21 0.16 0 .004 b.d. F 0.03 0.02 b.d. b.d, 0 .19 BaO b.d. b,d. b.d. b.d, 0,04 Calculated-wt % H20 1.19 1.18 4.03 Total 100.74 99.66 100.32 99.90 98.171 100.02 Formulae O 21.5 21.5 20  6 22  4 Si 3 ,619 3 .704 1.631 1.829 5.555 0 B 0.285 0.263 0.033 0 0 Al 6.583 6.536 8.446 0.335 3.061 1.603 Ti 0.005 0.004 0 .004 0.001 0 .082 0 Cr 0 0 0 0 0 0.001 Fe 3§ 0.253 0 ,396 Fe 2+ 0.752 0.753 0 .517 0.409 0.821 0.449 Mn 0.015 0 .026 0.011 0.008 0 0.005 Mg 3.168 3.088 3.098 1.415 4 .320 0.478 Zn 0 0 0 0 0 0.068 Li 0 .015 0.015 0 .002 0 0.001 Ca 0 .009 0.009 0.005 0 .006 0.003 0 Na 0 0 0 0 0 .104 0 K 0 0 0 0 1.870 0 Ba 0 .002 Total 14,450 14.400 14.000 4,003 15.8221 3 .000 Anions F 0 .012 0,008 0.087 OH 0,988 0 ,992 3.913 XFe 0 .192 0 .196 0.143 0 ,224 0 .160  0 ,484 Notes: All Fe measured as FeO. Fe 3§ calculated in sapphirine and spinel assuming stoichiometry and 14 and 3 cations, respectively. H20 was calculated assuming ideal (OH+F) contents. Totals corrected for F=O. b.d.=below detection. Electron microprobe analyses by M. G, Yates; ion microprobe analyses by N. Marquez. 1. Totals for biotite include 0.02 wt % Rb20 and 0,001 wt % SrO; 0.002 Rb per formula unit; Cs20<0.001 wt% from ion microprobe analyses. 2. Spinel analysis is a quantitative EDS analysis with normalization to 100 wt %; remainin~g analyses are WDS. XFe=Fe2+/(Fe2++Ms) SHORT COMMUNICATIONS 249 cordierite, sapphirine, spinel, apatite, monazite, zircon, and sericite. Sapphirine grains are 0.1-1 ram, the larger ones are cored by spinel. The cordierite is extensively altered, but the sericite appears to have formed from another mineral, possibly calcic plagioclase (microprobe analyses of some patches correspond to muscovite, others, to a phase rich in Ca, A1, and Si). The biotite schist at 221.5 m (15/221.5) contains minor K-feldspar, sillimanite and corundum in addition to the minerals in the schist at 152.7 m. However, the sericitic patches are absent and cordierite is largely fresh. Most sapphirine forms elongated symplectites with cordierite, perthitic K-feldspar, and fine sillimanite. A few grains (to 1.5 mm) of sapphirine in biotite may also be in this symplectite where the symplectite lies nearly perpendicular to the plane of the thin section. Sillimanite also forms prisms in cordierite and in biotite adjacent o sapphirine. Corundum forms grains less than 1 mm across in biotite and cordierite. At the University of Maine (UM), the silicate minerals in 15/154.2 were analysed with a wave- length-dispersive (WDS) MAC 400s electron microprobe (20 nA specimen current on quartz at 15 kV), whereas pinel in 15/154.2 was analysed with an energy-dispersive (EDS) Link AN 10000 system (Table 1). The Link system was also used to search for constituents with Z > 10; only those given in Table 1 were detected. Each mineral was analysed at one spot (kornerupine at two spots on one grain) within an area 2 mm across; the analysed spinel was located about 1.5 cm from this area. At the Institute of Experimental Mineralogy (IEM), minerals in all three samples were analysed with an EDS on a Camebax electron microprobe quipped with a Link detec- tor; a few minerals in 15/221.5 were analysed by EDS on the scanning electron microscope Tesla BS-301 with an Ortec detector (selected analyses are listed in Table 2). The IEM analyses have been normalised to a specified total. The tabu- lated data are averages (except spinel and K- feldspar) of analyses at several points on one or several grains. The EDS analyses of silicate minerals in 15/154.2 done at 1EM are in good agreement with the WDS analyses done at UM. The silicate minerals in 15/154.2 were analysed at the same spots as the WDS with an ARL ion microprobe mass analyser at the Aerospace Corporation (method given in Grew et al., 1990b). Kornerupine in sample B.M. 1940,39 was analysed concurrently as an internal standard, resulting in the following values (in weight percent): Li20 0.20, BeO 0.035, B203 3.72, and F 0.66, in fair (BeO) to good agreement with the wet chemical and ion microprobe data reported by Grew et al. (1990b). Compared to the 31 kornerupine samples discussed by Grew et al. (1990b), the Kola kornerupine is poor in boron and fluorine and intermediate in Fe/Mg ratio. Total AI + B = 6.80-6.87 atoms per formula unit, which is at the upper limit for kornerupine associated with orthopyroxene. Idealised F-OH distribution between kornerupine and biotite, which is (F/ OH)Krn/(F/OH) BI = 0.36-0.54, overlaps the range of values for kornerupine associated with Ti-poor biotite. The relatively high Fe3+/Fe 2+ ratios calculated for sapphirine suggest that Fe 3+ could also be present in kornerupine, but we have no way to analyse for it. Orthopyroxene A1203 content is mostly 5.4- 6.9 wt.%, but locally reaches 8 wt.% (e.g. Table 1). The other minerals in 154.2 are relatively homogeneous, and, in general, the compositions tabulated in Table 2 are representative of the analysed points in this sample and in the other two samples. For example, in a second section of 15/154.2, biotite TiO2 and AlzO3 contents aver- age 0.73 and 17.79 wt.%, respectively, and sapphirine SiO2 and A1203 average 14.24 and 60.69 wt.%, respectively, although orthopyrox- ene (Xv~ = 0.21) and biotite (Xw = 0.14) are slightly more magnesian (cf. Table 2). On the other hand, sapphirine in 15/221.5 is hetero- geneous; some spots in the symplectite contain less than 60 wt.% AlzO3, the difference being made up by Fe or Cr. K-feldspar varies in Na20 and BaO contents. Comparison of the compositions from the three rocks shows that the most important difference is the extent of Tschermak substitution, (Mg,Fe)- SiAl_ z (Table 2). AI20 3 contents of sapphirine and biotite increase systematically from the least aluminous assemblage with orthopyroxene + kornerupine in 15/154.2 to the most aluminous assemblage with sillimanite + corundum in 15/ 221.5. Decrease in Fe2+/Mg ratio of this sequence is less marked. Temperatures calculated from coexisting bio- tite and orthopyroxene in 15/154.2 (Tables 1-2 and Konilov, unpublished data on a second section) are 693-749~ and 706-728~ (for pressures of 4--5 kbar) from the calibrations of Aranovich et al. (1988) and Sengupta et al. (1990), respectively. These estimates, although reason- able for granulite-facies metamorphism, are higher than the value of 670 + 20~ which Fonarev et al. (1989; in press) reported as the peak conditions for the region as a whole on the basis of several geothermometers. The Sholt-Yavr biotite schist has several 250 SHORT COMMUNICAT IONS Table 2. Electron microprobe analyses of minerals in sapphirine-bearing rocks from Sholt-Yavr, Kola Peninsula, USSR. Sapphirine Spinel Opx Biotite Cordierite K-feldspar 15/ 154.2 152.7 221.5 152.7 154.2 154.2 152.7 221.5 152.7 221.5 221.5 wt% SiO2 13.90 12.49 11.86 0 51.40 38.80 38.12 37.64 49.99 50.58 TiO2 0.02 0.02 0.02 0.05 0.04 0.83 1.23 1.06 0.03 0.02 A1203 59.92 62.40 64.78 64.11 6.28 17.53 18.72 19.44 34.45 34.10 Cr203 0.02 0.05 0.04 0 0.02 0.05 0.03 0.02 0.01 FeO 7.85 6.93 5.12 16.18 14.07 6.73 6.93 6.05 2.02 1.77 MnO 0.15 0.11 0.15 0.20 0.36 0.04 0.06 0.04 0.08 0.09 MgO 17.74 17.83 17.74 17.13 27.34 20.85 20.26 20.10 13.26 12.99 CaO 0.08 0.03 0.03 0.05 0.15 0.02 0.04 0.09 0.08 0.04 Na20 0.28 0.11 0.16 0.72 0.32 0.30 0.31 0.36 K20 0.03 0.03 0.10 0.03 0.04 9.88 9.59 10.25 0.07 0.04 Other 1.551 64.75 0.16 19.05 0.09 0.19 1.27 13.86 0.632 Total 100.00 100.00 100.00 100.00 100.00 95.00 95.00 95.01 100.00 100.00 100.00 Formulae O 20 20 20 4 6 22 22 22 18 18 8 Si 1.652 1.475 1.394 0 1.844 5.571 5.465 5.403 4.928 4.980 [4IA1 4.348 4.525 4.606 1.955 0.156 2.429 2.535 2.597 4.002 3.957 [6]A1 4.046 4.158 4.366 0.109 0.537 0.628 0.692 Ti 0.002 0.002 0.002 0.001 0.001 0.090 0.133 0.114 0.002 0.001 Cr 0.002 0.005 0.004 0.002 0.006 0.003 0.002 0.001 Fe 3+ 0.296 0.356 0.232 0.044 Fe 2§ 0.485 0.328 0.271 0.306 0.422 0.808 0.831 0.726 0.167 0.146 Mn 0.015 0.011 0.015 0.004 0.011 0.005 0.007 0.005 0.007 0.008 Mg 3.144 3.138 3.108 0.661 1.462 4.463 4.330 4.301 1.949 1.907 Ca 0.010 0.004 0.004 0.006 0.003 0.006 0.014 0.008 0.004 Na 0.023 0.084 0.086 0.069 K 0.002 1.810 1.754 1.877 0.009 0.005 Other 0.0301 -- Total 14.000 14.002 14.001 3.000 4.035 15.802 15.695 15.818 11.070 11.077 XFe 0.134 0.095 0.080 0.316 0.224 0.153 0.161 0.144 0.079 0.071 2.976 1.032 0.006 0.003 0.009 0.113 0.813 0.0112 4.964 Note: All Fe measured as FeO. Analyses normalized to t00 wt% for all minerals except biotite, normalization is 95%. Fe3+/Fe 2§ ratio calculated from stoichiometry, assuming cations total 14 in 3 in spinel. Na and K contents of sapphirine and spinel and Ca in spinel are assumed to be Analyses by A. N. Konilov. 1. ZnO and Zn. 2. BaO and Ba. XFe=Fe2+/(Fe2++Ms) features in common with sil ica-undersaturated, kornerupine-bearing rocks elsewhere; for ex- ample, kornerupine overgrowths on sapphirine are characteristic of similar rocks from the Namaqualand complex in South Africa (Waters and Moore,  1985) and the Usmun River, Aldan shield, Russia (Grew et al., 1989, 1991). Forma- tion of these overgrowths in the Namaqualand rocks was attributed to introduction of fluids, whereas its formation in the Aldan rocks was attributed to partial melting and breakdown of tourmaline. The Sholt-Yavr kornerupine could be associated with the metasomatic reworking that Fonarev et al. (1989) inferred had accom- panied the high-grade metamorphism. In this case, a much simplified reaction for kornerupine formation with introduction of aqueous fluids could be: for which sapphirine, negligible. 7(Mg,Fe)SiO3 (in orthopyroxene) + 0.15B203 + 0.5H20 (in fluid) = (Mg,Fe)3.7A16.6B0.3Si3.7021(OH)(kornerupine) + 3.3(Mg,Fe)SiAI_2 The kornerupine composition has been simpli- fied from the analyses, in which (Mg + Fe + Mn) > Si (Table 1). Thus an SiO2-poor phase such as sapphirine would also be needed as a reactant to balance the equation. (Mg,Fe)SiAI_2 represents the Tschermak substitution and implies a shift to less aluminous compositions in orthopyroxene, sapphirine, and biotite. Waters (1986) proposed an analogous equation for sapphirine formation from cordierite and spinel, which accompanied a shift to less aluminous compositions in phlogo- pite. This shift need not have been large because kornerupine is so much less abundant than SHORT COMMUNICATIONS sapphirine, phlogopite, and orthopyroxene in the Sholt-Yavr rock. Boron could have been intro- duced with the aqueous fluid. However, a more likely source is sapphirine, which contains enough B20 3 for kornerupine to form given the abun- dance of sapphirine relative to kornerupine. Acknowledgements. Financial support from the U.S. National Science Foundation Grant DPP-8815863 to the University of Maine is acknowledged. We thank V. I. Fonarev and K. Kh. Avakyan for their assistance and P. C. Grew for comments on an earlier draft. References Aranovich, L. Ya., Lavrent'yeva, I. V., and Kosya- kova, N, A. (1988) Geokhimiya, no. 5, 668-76 (in Russian). Avakyan, K. Kh. and Buyakayte, M. I. (1991) Izvest. Akad. nauk SSSR., Ser. geol., in press (in Russian). - - - -and  Lyapunov, S. M. (1991) Geokhimiya, no. 5,635-41 (in Russian). Fonarev, V. I., Konilov, A. N., Grafchikov, A. A., and Avakyan, K. Kh. (1989) In The crystalline crust in space and time. Metamorphic and hydrothermal processes (V. A. Zharikov and V. I. Fonarev, eds) pp. 29-44, Moscow, Nauka (in Russian with English abstract). (in press) Europ. J. Mineral. Grew, E. S., Yates, M., Marquez, N., Beryozkin, V. I., and Kitsul, V. I. (1989) Dokl. Akad. Nauk SSSR, 3119, 423-8 (in Russian). 251 Litvinenko, A. K. and Pertsev, N. N. (1990a) Episodes, 13, 270-4. - -Chernosky ,  J. V., Werding, G., Abraham, K., Marquez, N., and Hinthorne, J. R. (1990b) J. Petrol., 31, 1025-70. - -Yates ,  M. G., Beryozkin, V. I. and Kitsul, V. I. (1991) Geol. Geofiz., no. 5, 78-87, and no. 7, 99-116 (in Russian). Kitsul, V. I., Brovkin, A. A., Lutts, B. G., Parinova, Z. F., and Kuznetsova, I. K. (1972) Dokl. Akad. Nauk SSSR, 21}6, 1190-3 (in Russian). Kuryleva, N. A. (1960) Zap. Vses. Mineral. Obschch., 2nd Ser. 89, 711-3 (in Russian). Levitskiy, V. I., Terekhov, Ye. N., Medvedeva, T. I., Bogdanova, G. V., Sapozhnikov, A. N., and Guni- cheva, T. N. (1988) Dokl. Akad. Nauk SSSR, 302, 679-83 (in Russian). - - - -Sapozh inkov ,  A. N., and Khaltuyeva, V. K. (1990) Mineral. Zhurn., 12, no. 5, 58-68 (in Russian). Nalivkina, E. B. (1959) Mineral. Sbornik L'vovsk. Geol. Obshch., 13, 158-77 (in Russian). Rusanov, M. S., and Suslova, S. N. (1984) In The Superdeep Well of the Kola Peninsula (Ye. A. Kozlovsky, ed.), pp. 17-39, Berlin Heidelberg, New York, Springer-Verlag. Sengupta, P., Dasgupta, S., Bhattacharya, P. K., and Mukherjee, M. (1990) J. metamorphic Geol., 8, 191-7. Waters, D. J. (1986) J. Petrol., 27,541-65. and Moore, J. M. (1985) Contrib. Mineral. Petrol., 91,369-82. [Manuscript received 8July 1991: revised 27 August 1991] (~ Copyright he Mineralogical Society KEYWORDS: kornerupine, sapphirine, orthopyroxene, biotite, spinel, Kola Peninsula, Russia. Department of  Geological Sciences, EDWARD S. GREW University of Maine, MARTIN G. YATES Orono, Maine 04469, U.S.A. Institute of Experimental Mineralogy A.N.  KONILOV of the Russian Academy of  Sciences, 14232 Chernogolovka, Moscow district, Russia Aerospace Corporation, NICHOLAS MARQUEZ Los Angeles, California 90009, U.S.A. 

Kornerupine from the Archean Kola Series at Sholt-Yavr, Kola Peninsula, Russia

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Kornerupine from the Archean Kola Series at Sholt-Yavr, Kola Peninsula, Russia

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