-Meta-sediments in the Larsemann Hills that preserve a coherent stratigraphy, form a cover sequence deposited upon basement of mafic-felsic granulite. Their outcrop pattern defines a 10 kilometre wide east-west trending synclinal trough structure in which basement-cover contacts differ in the north and the south, suggesting tectonic interleaving during a prograde, D p thickening event. Subsequent conditions reached low-medium pressure granulite grade, and structures can be divided into two groups, D 2 and D 3 , each defined by a unique lineation direction and shear sense. D 2 structures which are associated with the dominant gneissic foliation in much of the Larsemann Hills, contain a moderately east-plunging lineation indicative of west-directed thrusting. D 2 comprises a colinear fold sequence that evolved from early intrafolial folds to late upright folds. D 3 structures are associated with a high-strain zone, to the south of the Larsemann Hills, where S 3 is the dominant gneissic layering and folds sequences resemble D 2 folding. Outside the D 3 high-strain zone occurs a low-strain D 3 window, preserving low-strain D 3 structures (minor shear bands and upright folds) that partly re-orient D 2 structures. All structures are truncated by a series of planar pegmatites and parallel D 4 mylonite zones, recording extensional dextral displacements. D 2 assemblages include coexisting garnet-orthopyroxene pairs recording peak conditions of 7 kbar and ~ 780 °C. Subsequent retrograde decompression textures partly evolved during both D 2 and D 3 when conditions of ~ 4-5 kbar and ~ 750 °C were attained. This is followed by D 4 shear zones which formed around 3 kbar and ~ 550 °C.It is tempting to combine D,,^ structures in one tectonic cycle involving prograde thrusting and thickening followed by retrograde extension and uplift. The available geochronological data, however, present a number of interpretations. For example, D 2 was possibly associated with a clockwise P-T path at medium pressures around ~ 1000 Ma, by correlation with similar structures developed in the Rauer Group, whilst D 3 and D 4 events occurred in response to extension and heating at low pressures at ~ 550 Ma, associated with the emplacement of numerous granitoid bodies. Thus, decompression textures typical for the Larsemann Hills granulites maybe the combined effect of two separate events.

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The presence of polyphase shear zones transected by several suites of dolerite dykes in Archaean basement of the Vestfold Hills, East Antarctica, allows a detailed reconstruction of the local structural evolution. Archaean and early Proterozoic deformation at granulite facies conditions was followed by two phases of dolerite intrusion and mylonite generation in strike-slip zones at amphibolite facies conditions. A subsequent middle Proterozoic phase of brittle normal faulting led to the development of pseudotachylite, predating intrusion of the major swarm of dolerite dykes around 1250 Ma. During the later stages and following this event, pseudotachylite veins were reactivated as ductile, mylonitic thrusts under prograde conditions, culminating in amphibolite facies metamorphism around 1000–1100 Ma. This is possibly part of a large-scale tectonic event during which the Vestfold block was overthrust from the south. In a final phase of strike-slip deformation, several pulses of pseudotachylite-generating brittle faulting alternated with ductile reactivation of pseudotachylite.

The structural geology and tectonic setting of hydrothermal gold deposits are paramount in understanding their genesis, and for their exploration. Strong structural control on mineralization is one of the defining features of these deposits, and arises because the permeabilities of crustal rocks are too low to allow the formation of hydrothermal deposits on realistic time scales unless rocks are deformed. Deformation zones and networks of deformation zones are the fundamental structures that control mineralization. Systematically analyzing deposit geometry, kinematics and dynamics leads to the most thorough comprehension of a deposit. Geometrical analysis relates ore body shape to controlling structures, and networks of deformation zones can be analyzed using topology to understand their connectivity and mineralizing potential. Kinematic analysis determines the location of permeability creation and mineralization. New views of shear zone kinematics allow for variable ratios of pure to simple shear, which change likely directions of mineralization. Multiple orientations of mineralized deformation zones may form simultaneously and symmetrically about the principal strain axes. Dynamic analysis is necessary for a mechanical understanding of deformation, fluid flow and mineralization, and can be achieved through numerical modeling. The relationship between deformation (kinematics) and stress (dynamics) constitutes the rheology: rheological contrasts are critical for the localization of many deposits. Numerous gold deposits, especially the largest, have evidence for multiple mineralizing events that may be separated by tens to hundreds of millions of years. In these cases, reactivation of structures is common, and a range of orientations of pre-existing structures are predicted to be reactivated, given that they are weaker than intact rock. Physical and chemical processes of mineralization can be integrated using a nonequilibrium thermodynamics approach.Hydrothermal gold deposits form in contractional, strike-slip and extensional tectonic settings.However there may be great variation in the spatial scale over which the tectonic setting applies, and tectonic settings may also change on rapid time scales, so that it is inadvisable to infer local tectonics from deposit-scale patterns, and visa versa. It is essential to place mineralizing events within a complete geological history in order to distinguish pre-and post-mineralizing structures from syn-mineralization deformation features.