This volume is a field guide to the base of the Bega Batholith. The field guide describes a trip to examine granite plutons, layered mafic complexes and related country rocks. These rocks are slightly younger (~422 Ma) than those at Cooma (~435 Ma), ~70 km to west. At Cooma we can view some classic metamorphic rocks with well-developed structures and obvious migmatitic leucosomes. In contrast, the structures and rocktypes observed on this trip are unusual. The granite is a classic granodiorite but the migmatites are schlieren migmatites and are quite distinct from the classic layered migmatites (metatexites) which are common in high-temperature metamorphic complexes around the world.

Many of the magmatic structures and features observed over the two days are comparable to sedimentary structures so much of the trip will be focused on identification and interpretation of these structures and how the recognition of these features influences our view of mechanisms of pluton construction. In turn, we can discuss the role that plutons can play as a significant tectonic indicator, just like classic structures such as folds and faults