• journal_title：Journal of the Geological Society
• Contributor：L. Tajčmanová ; I. Soejono ; J. Konopásek ; J. Košler ; U. Klötzli
• Publisher：Geological Society of London
• Date：2010-
• Format：text/html
• Language：en
• Identifier：10.1144/0016-76492009-086
• journal_abbrev：Journal of the Geological Society
• issn：0016-7649
• volume：167
• issue：2
• firstpage：329
• section：Research Article

At the northeastern edge of the Moldanubian Zone, a large body of felsic to intermediate granulite with relics of high-pressure mineral assemblage is exposed within medium-grade paragneisses, micaschists and metagranites. A polyphase tectonic evolution in the study area resulted in three deformation phases (D₁–D₃). Peak metamorphic conditions (860–1000 °C and 16 kbar) in granulites are interpreted as reflecting an early stage of the high-grade evolution of the orogenic lower crust. These conditions were followed by exhumation of the orogenic lower crustal block to mid-crustal levels (6–8 kbar). In contrast to this, the study of metamorphic conditions in the surrounding micaschists (660 °C and 8 kbar) shows that these rocks never experienced pressures and temperatures of the orogenic lower crust. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb dating of zircon from the granulite yielded a concordia age of 354 ± 7 Ma, whereas the conventional isotope dilution thermal ionization mass spectrometry (ID-TIMS) and LA-ICP-MS dating of xenotime gave identical concordia ages of 336.2 ± 1.2 and 339 ± 3 Ma, respectively. Combination of new structural and petrological results with LA-ICP-MS zircon and xenotime dating leads to development of a well-constrained exhumation model and brings new insights into the behaviour of lower crustal rocks during orogenesis.