New Data on the Age (U-Pb, Sm-Nd) of Garnetites from Salma Eclogites of the Belomorian Mobile Belt

摘要

The origin of garnetites, which are quite abundant in high-pressure metamorphic complexes, is still debatable. The idea about primary magmatic differentiation of basites to Fe-Ti (garnetite protolith) and Mg (protolith of metabasite complimentary to garnetite) parts is the most popular [1 and others]. There are assumptions about the formation of garnetite as a result of metamorphic differentiation from active infiltration of fluid [2] and metasomatism with the formation of a metasomatic column [3].