Episodic construction of the Tatra granitoid intrusion (Central Western Carpathians, Poland/Slovakia): consequences for the geodynamics of Variscan collision and Rheic Ocean closure

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• 作者：Aleksandra Gawęda ; Jolanta Burda ; Urs Klötzli…
• 刊名：International Journal of Earth Sciences
• 出版年：2016
• 出版时间：June 2016
• 年：2016
• 卷：105
• 期：4
• 页码：1153-1174
• 全文大小：3,580 KB
• 刊物类别：Earth and Environmental Science
• 刊物主题：Earth sciences
  Geology
  Geophysics and Geodesy
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1437-3262
• 卷排序：105

文摘

The Tatra granitoid pluton (Central Western Carpathians, Poland/Slovakia) is an example of composite polygenetic intrusion, comprising many magmatic pulses varying compositionally from diorite to granite. The U–Pb LA-MC-ICP-MS zircon dating of successive magma batches indicates the presence of magmatic episodes at 370–368, 365, 360, 355 and 350–340 Ma, all together covering a time span of 30 Ma of magmatic activity. The partial resorption and recycling of former granitoid material (“petrological cannibalism”) was a result of the incremental growth of the pluton and temperature in the range of 750–850 °C. The long-lasting granitoid magmatism was connected to the prolonged subduction of oceanic crust and collision of the Proto-Carpathian Terrane with a volcanic arc and finally with Laurussia, closing the Rheic Ocean. The differences in granitoid composition are the results of different depths of crustal melting. More felsic magmas were generated in the outer zone of the volcanic arc, whilst more mafic magmas were formed in the inner part of the supra-subduction zone. The source rocks of the granitoid magmas covered the compositional range of metapelite–amphibolite and were from both lower and upper crust. The presence of the inherited zircon cores suggests that the collision and granitoid magmatism involved crust of Cadomian consolidation age (c. 530 and 518 Ma) forming the Proto-Carpathian Terrane, crust of Avalonian affinity (462, 426 Ma) and melted metasedimentary rocks of volcanic arc provenance.KeywordsGranitoidMagmatic pulsesVariscan orogenyProto-Carpathian Terrane