TY - JOUR A1 - Ferrero, Silvio A1 - Borghini, Alessia A1 - Wunder, Bernd A1 - Walle, Markus A1 - Günter, Christina A1 - Ziemann, Martin Andreas T1 - A treasure chest full of nanogranitoids BT - an archive to investigate crustal melting in the Bohemian Massif JF - Metamorphic Geology: Microscale to Mountain Belts N2 - The central European Bohemian Massif has undergone over two centuries of scientific investigation which has made it a pivotal area for the development and testing of modern geological theories. The discovery of melt inclusions in high-grade rocks, either crystallized as nanogranitoids or as glassy inclusions, prompted the re-evaluation of the area with an ‘inclusionist’ eye. Melt inclusions have been identified in a wide range of rocks, including felsic/perpotassic granulites, migmatites, eclogites and garnet clinopyroxenites, all the result of melting events albeit over a wide range of pressure/temperature conditions (800–1000°C/0.5–5 GPa). This contribution provides an overview of such inclusions and discusses the qualitative and quantitative constraints they provide for melting processes, and the nature of melts and fluids involved in these processes. In particular, data on trace-element signatures of melt inclusions trapped at mantle depths are presented and discussed. Moreover, experimental re-homogenization of nanogranitoids provided microstructural criteria allowing assessment of the conditions at which melt and host are mutually stable during melting. Overall this work aims to provide guidelines and suggestions for petrologists wishing to explore the fascinating field of melt inclusions in metamorphic terranes worldwide, based on the newest discoveries from the still-enigmatic Bohemian Massif. Y1 - 2018 SN - 978-1-78620-400-4 U6 - https://doi.org/10.1144/SP478.19 SN - 0305-8719 VL - 478 SP - 13 EP - 38 PB - Geological Soc Publishing House CY - Bath ER - TY - JOUR A1 - Borghini, Alessia A1 - Ferrero, Silvio A1 - Wunder, Bernd A1 - Laurent, Oscar A1 - Ziemann, Martin Andreas T1 - Granitoid melt inclusions in orogenic peridotite and the origin of garnet clinopyroxenite JF - Geology N2 - Granitic melt inclusions were found in layers of garnet clinopyroxenites from orogenic peridotites hosted in high-pressure felsic granulites of the Granulitgebirge, central Europe. The inclusions are both glassy and crystallized, and occur as clusters in the garnet. Microstructural features suggest that the inclusions formed while garnet was growing as a peritectic phase, likely alongside clinopyroxene. The chemistry of the melt, in particular its trace element signature, shows a crustal contribution, probably due to the involvement of phengite in the melt-producing reaction, most likely in the presence of a fluid. The presence of a granitoid melt in mantle rocks may be the result of localized melting of a phengite-bearing protolith either already present in the peridotites or, more likely, within the local deeply subducted crustal units. In the latter case, the melt would have infiltrated the peridotites and generated pyroxenite via metasomatism. In either case, the presence of granitoid inclusions in orogenic peridotite provides direct evidence for a genetic connection between a high-pressure crustal melt and garnet pyroxenites. The in situ characterization of these remnants of natural melt provides direct quantitative constraints on (one of) the agents responsible for the interaction between crust and mantle. Y1 - 2018 U6 - https://doi.org/10.1130/G45316.1 SN - 0091-7613 SN - 1943-2682 VL - 46 IS - 11 SP - 1007 EP - 1010 PB - American Institute of Physics CY - Boulder ER -