SROVNÁNÍ CHEMISMU TŘEBÍČSKÉHO DURBACHITU A JINÝCH DURBACHITŮ

Petr Sulovsky

Abstrakt

The Třebíč massif, composed mostly of ultrapotassic igneous rocks known as durbachites (melanogranite to melanosyenite), is the third most radioactive batholith in Czechia. The heavy mineral concentrates panned from bottom sediments of streams flowing across the massif, however, do not show a corresponding regional anomaly. The paper presents results of the first year research project focused on the explanation of this discrepancy. Based on large-scale sampling (117 samples taken at 49 sites), the distribution of U and Th follows the blocky pattern revealed by Bubeníček in 1968. The bulk rock chemistry of Třebíč durbachites confirmed their close similarity with other ultrapotassic rocks of the world and the "mixed" nature of their magma (matle / crustal sources). Both major and trace element concentrations indicate their association with collisional (syn- and post-) tectonic settings.

Bibliografická citace

Sulovsky, P. (2016). SROVNÁNÍ CHEMISMU TŘEBÍČSKÉHO DURBACHITU A JINÝCH DURBACHITŮ. Geologické výzkumy na Moravě a ve Slezsku, 7. Získáno z https://journals.muni.cz/gvms/article/view/5124

Klíčová slova

durbachite; radioactivity; trace elements; ultrapotassic rocks; Třebíč massif

Plný Text:

Reference

Zobrazit literaturu Skrýt literaturu

Batchelor, R. A. - Bowden, P. (1985): Petrogenetic interpretation of granitoid rock series using multicationic parameters. - Chemical Geology, 48, 43-55.

Bevins, R. E. - Kokelaar, B. P. - Dunkley, P. N. (1984): Petrology and geochemistry of lower to middle Ordovician igneous Wales: a volcanic arc to marginaal basin transition. - Proc. Geol. Ass., 95, 337-347.

Boynton, W. V. (1984): Geochemistry of rare earth elements: meteorite studies. In: Henderson P. (ed.): Rare element geochemistry. - Elsevier, 63 - 114.

Bubeníček, J. (1968): Distribuce některých stopových prvků v třebíčském masívu. - Čas. Mineral. Geol., 13, 285-299.

Foley, S. F. - Venturelli, G. - Green, D. H. - Toscani, L. (1987): The ultrapotassic rocks: characteristics, classification, and constraints for petrographic models. - Earth-Sci. Rev., 24, 81-134.

Foley, S. F. (1992): Petrological characterisation of the source components of potassic magmas: geochemical and experimental constraints. - Lithis, 28, 187-204.

Gerdes, A. (1997): Geochemische und thermische Modelle zur Frage der spatoregenen Granitgneise am Beispiel des Sudbohmischen Batholiths: Basaltisches Underplating oder Krustenstapelung? - PhD disertace, Gottingen 1997.

Goliáš, V. (1995): Radioaktivní akcesorické minerály třebíčského masívu. - Bull. min.-petr. odd. NM v Praze, 3, 56-60.

Holub, F. V. (1997): Ultrapotassic plutonic rocks of the durbachite series in the Bohemian Massif: Petrology, geochemistry and petrogenetic interpretation. - Sbor. geol. věd, ser. Loisková geologie, mineralogie, 31, 5-25.

Houzar, S. - Novák, M. (1998): Fluorine-enriched rocks on exocontact of the Třebíč Durbachite Massif: evidence from underlying chondrodite marbles. - Acta Univ. Carol., (Abstract Vol. conf. POCEEL), 42:2, 267. Praha.

Janoušek, V. - Bowes, D. R. - Rogers, G. - Farrow, C. M. - Jelínek, E. (2000 - in press): Modelling diverse processes in the petrogenesis of a composite batholith: the Central Bohemian Pluton, Central European Hercynides. - Jour. Petrol., 41 (4).

Miller, C. - Schuster, R. - Klötzli, U. - Frank, W. - Purtscheller, F. (1999): Post-collisional and ultrapotassic magmatism in SW Tibet: Geochemical and Sr-Nd-Pb-O isotopic constraints for mantle source characteristic and petrogenesis. - Jour. Petrol., 40(9), 1399-1424.

Pearce, J. A. (1982): Trace element characteristics of lavas from destructive plate boundaries. In: Thorpe R.R. (ed.), Andesites. - Wiley, Chichester, 525-548.

Pearce, J. A. - Harris, N. B. W. - Tindle, A. G. (1984): Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. - Journal of Petrology, 25, 956-983.

Schaltegger, U. - Gnos, E. - Kupfer, T. - Labhart, T. P. (1991): Geochemistry and tectonic significance of Late Hercynian potassic and ultrapotassic magmatism in the Aar Massif (Central Alps). - Schweiz. Mineral. Petrogr. Petrogr. Mitt. 71, 391 - 403, 1991.