Charakterystyka morfologiczna i geochemiczna kryształów cyrkonu z migmatytu ze Smreczyńskiego Wierchu (Tatry Zachodnie)

• Autorzy: Burda J.

Warianty tytułu

EN

Morphological and geochemical characteristics of zircon crystals from Smreczyński Wierch migmatite (Western Tatra Mts.)

• Języki publikacji: PL

Abstrakty

EN

In the Polish part of the metamorphic envelope of the granitoid Rohače pluton, migmatites are the predominant component. Migmatisation took place in the amphibolite facies conditions (T = 690–780C ; P =7.5–11 kbar). To observe the response of zircon crystals to the melt formation, zircon from the anatectic group of migmatites was investigated (both from leucosome and mesosome of stromatitic migmatite). Different generations of zircon present in leuco- and mesosome reflect different geological processes acting during the rock formation. Zircon from leucosome represent mainly the euhedral varieties, with two typological maxima: S_1-2 (I generation) and S_21-22 (II generation). Zircon from mesosome represents the anhedral varieties with one maximum at S₁ (I gen-eration). In CL images the first generation (S_1-2) comprises an inherited core surrounded by younger metamorphic and magmatic rims. The microchemical analyses showed that the inherited cores have higher Zr/Hf ratios than the overgrowing rims. The second genera-tion (S_21-22) revealed only oscillatory zonation. The zones with strong luminescence are characterized by a decrease of Hf and U con-tent. Zircon showing polyphase internal structure might represent a component of mesosome which survived the dissolution in granitic melt, while zircon with oscillatory zonation might have crystallized from anatectic melt.

Słowa kluczowe

PL

kryształ cyrkonu; katodoluminescencja; migmatytyzacja

EN

zircon morphology; cathodoluminescence; migmatites; Tatra Mts.

• Wydawca: Państwowy Instytut Geologiczny - Państwowy Instytut Badawczy
• Czasopismo: Przegląd Geologiczny
• Rocznik: 2005
• Tom: Vol. 53, nr 2
• Strony: 127--133
• Opis fizyczny: Bibliogr. 18 poz., rys., tab., wykr.

Twórcy

autor

Burda J.

• Wydział Nauk o Ziemi, Uniwersytet Śląski, ul. Będzińska 60, 41-200 Sosnowiec

Bibliografia

• 1. BAC-MOSZASZWILI M. 1996 - Podnoszenie masywu Tatr w trzecio- i czwartorzędzie. [W:] Mater. I Ogólnopol. Konf., Zakopane 6-9.10.1995: 68-71.
• 2. BENISEK A. & FINGER F. 1993 - Factors controlling the development of prism faces in granite zircons: a microprobe study. Contrib. Mineral. Petrol., 114: 441-451.
• 3. BROSKA I. 2000 - Accesory mineral phases as a petrologic tool of the West Carpathian granite typology. Polskie Towarzystwo Miner. Pr. Spec., 17: 125-127.
• 4. BURDA J. & GAWĘDA A. 1997 - Mass-balance calculations in migmatites from the Upper Kościeliska Valley (The Western Tatra Mts., S Poland). Miner. Pol., 28: 53- 68.
• 5. BURDA J. & GAWĘDA A. 1999 - Petrogeneza migmatytów z górnej części Doliny Kościeliskiej w Tatrach Zachodnich. Arch. Miner., 52: 163-194.
• 6. GAWĘDA A., KOZŁOWSKI K. & PIOTROWSKA K. 1998 - Tectonic development of the crystalline basement of the Polish part of the Western Tatra Mts. Acta Universitatis Carolinae - Geologica, 42: 252-253.
• 7. GAWĘDA A., KOZŁOWSKI K. & PIOTROWSKA K. 2000 - Early Variscan collision and generation of leucogranite melts in the Western Tatra Mountains (S Poland, W Carpathians). Jour. Czech. Geol. Soc., Abstr., 45: 230.
• 8. GUPTA L. N. & JOHANNES W. 1985 - Effect of metamorphism and partial melting of host rocks on zircons. Jour. Metam. Geol., 3: 311-323.
• 9. HANCHAR J.M. & MILLER C.F. 1993 - Zircon zonation patterns as revealed by cathodoluminescence and backscattered electron images: Implication for interpretation of complex crustal histories. Chem. Geol., 110: 1-13.
• 10. KOHUT M. & JANAK M. 1994 - Granitoids of the Tatra Mts., Western Carpathians: Field relations and petrogenetic implications. Geol. Carpath., 45: 301-311.
• 11. KOZ£OWSKI K. & GAWĘDA A. 1999 - Prewaryscyjska ewolucja metamorficzna kompleksu krystalicznego polskiej części Tatr Zachodnich. Pr. Uniw. Sl., Sosnowiec: 91-99.
• 12. NEMCHIN A.A., GIANNINI L.M., BODORKOS S. & OLIVER N.H.S. 2001 - Ostwald ripening as a possible mechanism for zircon overgrowth formation during anatexis: Theoretical constraints, a numerical model, and its application to pelitic migmatites of the Tickalara Metamorphics, northwestern Australia. Geochimica et Cosmochimica Acta 65/16: 2771-2787.
• 13. POLLER U., JANAK M., KOHUT M. & TODT W. 2000 - Early Variscan magmatism in the Western Carpathians: U-Pb zircon data from granitoids and orthogneisses of the Tatra Mountains (Slovakia). Inter. Jour. Earth Sc., 89: 336-349.
• 14. PUPIN J. P. 1980 - Zircon and granite petrology. Contribution to Mineralogy and Petrology, 73: 207-220.
• 15. RUBATTO D. & GEBAUER D. 2000 - Use of cathodoluminescence for U-Pb zircon dating by ion microprobe: some examples from the Western Alps. [W:] Pagel M., Barbin V., Blanc P., Ohnenstetter D. (ed.), Cathodoluminescence in geosciences: 373-400.
• 16. SCHALTEGGER U., FANNING C.M., GÜNTER D., MAURIN J.C., SCHULMANN K. & GEBAUER D. 1999 - Growth, annealing and recrystallization of zircon and preservation of monazite in high-grade metamorphism: conventional and in-situ U-Pb isotope, cathodolumine- scence and microchemical evidence. Contrib. Miner. Petrol., 134: 186-201.
• 17. VAVRA G., SCHMID R. & GEBAUER D. 1999 - Internal morphology, habit and U-Th-Pb microanalysis of amphibolite-to-granulite facies zircons: geochronology of the Ivrea Zone (Southern Alps) 134: 380-404.
• 18. VILLASECA C., MARTIN ROMERA C., DE LA ROSA J. & BARBERO L. 2003 - Residence and redistribution of REE, Y, Zr, Th and U during granulite-facies metamorphism: behaviour of accessory and major phases in peraluminous granulites of central Spain. Chem. Geol., 200: 293-323.