Stop 5 - Base of the Kameruka Pluton

This stop represents the same structural level as in the lower Wog Wog River (Day1 -Stop 2), where the sheeted nature of the Kameruka pluton is evident. A notable difference is the lack of abundant diatexite and granitic sheets. The basal contact is characterised by a narrow (15m wide) zone of leucocome-poor schlieren migmatites, some of which have hybridised with the granite. Hybridisation is characterised by the dispersal of Kameruka granodiorite xenocrysts throughout a finer grained diatexitic leucosome. Much of the structure of the migmatite is preserved within the hybrid zone with boudins of metasediment aligned parallel to flow-layering in the granite, defined by the crystal alignment of tabular plagioclase. This boudinage and crystal alignment suggests that hybridisation is shear related, as it is in the lower Wog Wog River. The paucity of leucosome at this location is considered to be significant. The presence of K-feldspar megacrysts in the diatexites indicates that much more leucosome must have been present to effectively hybridise and be dispersed throughout the migmatite. Thus, this zone possibly represents a site where leucosome has been removed from the migmatite, facilitated by compressive deformation during shearing. Migration of such leucosome material to higher levels could be represented by the diatexites that cut metatexites in shear zones or as accumulations in the axial planes of open folds (these are local F4 folds as discussed on Day 1).