if the quartz is re-crystallizing during anatexis, maybe it can trap anatectic melt. But I would expect it to be more a reactant than a product during partial melting...
So far, we have defined as nanogranites only crystallized melt inclusions whcih originally contained anatectic melt (see Ferrero et al., 2012, Cesare et al., 2009; Bartoli et al., 2013 on Geology). So, you have to state 1) the rock under investigation is actually a migmatite, then 2) that the host phase is likely to be a peritectic phase.
nanogranites have been reported only in garnet and ilmenite. we expect to find them as well in spinel, since it is a pretty strong mineral.
Thank you Silvio. Yes, Spinel is sometimes a pertitectic mineral in aluminous metamorphic rocks. Cordierite, like garnet (or both) are pertitectic minerals during partial melting of appropriate metamorphic rocks (magnesian pelites). But, i don't know if Crd is known as a fluid inclusion host (I'm not a specialist).
of course quartz is more "famous", however if you are interested in the topic you can take a look at "Cesare, B., Maineri, C., Baron Toaldo, A., Pedron, D. & Acosta–Vigil, A., 2007. Immiscibility between carbonic fluids and granitic melts during crustal anatexis: a fluid and melt inclusion study in the enclaves of the Neogene Volcanic Province of SE Spain. Chemical Geology, 237, 433–449". There cordierite may contain both melt and fluid inclusions.
Thank you Silvio and Driouch! In some of my studied migmatitic rocks, cordierite is a production of biotite breakdown, because during appearence of cordierite, biotite consumed and cordierite and orthoclase appear, meanwhile anatectic leucosomes develop in rocks. I am very interested to examine if nanogranite inclusions present in these rocks.
- Badges
- Science method