Generation, transportation and emplacement of postand anorogenic magmas in the Fennoscandian shield
To receive detailed information about the history coarse porphyritic ganites from different tectonic setting (post- and anorogenic), mineral inclusions in quartz and K-feldsparmegacrysts were studied. The result of the project was that the megacrysts were formed in mid-crustal magmachambers some 30 Ma before the emplacement of the granites in the upper crust. Anorogenic granites are known to represent crystallization in reduced environments (low Mg# of the mafic silicates). However, the mineral chemistry of mafic silicates in K-feldspar megacrysts is in contrast to this. The minerals have high Mg# and are enriched in Ba and Sr - typical features for post-orogenic granites. We thus don't rule out the possibility that there may be a petrogenetic connection between post- and anorogenic granites.