Fojtka hybrid granitoids - structural and lithological markers in the Krkonoše-Jizera Pluton

Geoscience Research Reports 47, 2014 (GRR for 2013), pages 120–125

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Abstract

Fojtka hybrid granitoids are represented by 20 km long belt of the irregular sheet-like bodies, autonomous blocks and swarms of the ellipsoidal microgranular mafic enclaves in the Krkonoše-Jizera Pluton. The shapes and composition of these bodies resemble the synmagmatic dykes, originally of basic composition which were intruded into liquid granitic magma. These basic intrusions were later intimately mingled and mixed with surrounding granite melt and modified into a miscellaneous series quartzmonzodiorite and more common granodiorite and monzogranite. Location of the Fojtka hybrid granitoids in the vicinity of the Liberec and Jizera granite gradational boundary support their function of the ribbons of the basic intrusions structuraly dividing the Krkonose-Jizera pluton into several subhorizontal layers.

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