Regionally metamorphosed carbonatite-like marbles from the varied group, moldanubian unit, bohemian massif, czech republic, and theiry Mo-Nb-REE mineralization

摘要

Unusual carbonatite-like marbles with Mo-Th-Nb-REE mineralization occur in the amphibolite facies metamorphic rocks at Blizna (Varied Group of Moldanubian Unit, Bohemian Massif). The geological position, mineralogy, mineral- and whole-rock geochemistry, as well as the isotopic composition of the host rocks shed light onto the origin of the mineralization. The carbonates were deposited in a shallow marine lagoonal environment (as indicated by the associated evaporites) and locally contained a large proportion of volcano-detritic material derived from contemporaneous alkaline (carbonatite-like) volcanism. Subsequently the whole assemblage was metamorphosed to produce the observed mineral paragenesis.