ISSN

print 2570-7337
online 2570-7345

Retrográdně metamorfovaný eklogit od Čejkova u Nového Rychnova (Moldanubikum, Česká republika)

Retrogradely metamorphosed eklogite from Čejkov near Nový Rychnov (Moldanubian Zone, Czech Republic)


Klíčová slova

Abstrakt

Two types of retrograde metamorphosed eclogite from Čejkov were investigated. The first type is pyroxene-bearing amphibolite with pseudomorphs after garnet (Ca-amphibole, clinopyroxene, plagioclase, orthopyroxene) without a visible structure of the original eclogite. The second type is retrograde metamorphosed eclogite with Ca and Fe-Mg-Mn-Li-amphibole, garnet, plagioclase, clinopyroxene and orthopyroxene that contain abundant clinopyroxene-plagioclase and orthopyroxene-plagioclase symplectites after omphacite (up to c. 75 vol. %). The symplectite rims garnet grains (pseudomorphs after garnet) and it is a common feature in  both rock types representing changes from eclogite to  amphibolite-granulite facies conditions.

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