Multi-batch, incremental assembly of a dynamic magma chamber: the case of the Peninsula pluton granite (Cape Granite Suite, South Africa)

摘要: The S-type Peninsula Pluton (South Africa) exhibits substantial compositional variability and hosts a large variety of mafic felsic magmatic enclaves with contrasting textures compositions. Moreover, the pluton is characterized by mechanical concentrations K-feldspar megacrysts, cordierite biotite, generating complex array structures including schlieren, pipes, spectacular sheeted structures. Chemical evidence indicates that constructed incrementally rapid emplacement numerous magma pulses. Field, textural data suggest form local flow at level highly viscous crystal-rich magmas (i.e. crystallinity up to 50 vol.%) through mushes assembled from older batches. At time arrival relatively late batches, some areas within had achieved crystal fractions allowed material act as solid, whilst maintaining enough melt prevent formation sharp intrusional contacts. Magmatic represent “snapshots” processes operate in multiphase their genesis due thermal instabilities chamber are triggered pulses new derived melting compositionally variable metasedimentary source.