Pods of granulite facies dioritic gneiss in the Pembroke Valley,
Milford Sound, New Zealand, preserve peritectic garnet
surrounded by trondhjemitic leucosome and vein networks, that
are evidence of high-P partial melting. Garnet-bearing
trondhjemitic veins extend into host gabbroic gneiss, where they
are spatially linked with the recrystallization of comparatively
low-P two-pyroxene-hornblende granulite to fine-grained high-P
garnet granulite assemblages in garnet reaction zones. New data
acquired using a Laser Ablation Inductively Coupled Plasma Mass
Spectrometer (LA-ICPMS) for minerals in various textural
settings indicate differences in the partitioning of trace
elements in the transition of the two rock types to garnet
granulite, mostly due to the presence or absence of
clinozoisite. Garnet in the garnet reaction zone (gabbroic
gneiss) has a distinct trace element pattern, inherited from
reactant gabbroic gneiss hornblende. Peritectic garnet in the
dioritic gneiss and garnet in trondhjemitic veins from th