Mineral deposits can be described in terms of their mineral systems, i.e., fluid source, migration pathway, and trap. Source regions are difficult to recognize in seismic images. Many orebodies lie on or adjacent to major fault systems, suggesting that the faults acted as fluid migration pathways through the crust. Large faults often have broad internal zones of deformation fabric, which is anisotropic. This, coupled with the metasomatic effects of fluids moving along faults while they are active, can make the faults seismically reflective. For example, major gold deposits in the Archaean Eastern Goldfields province of Western Australia lie in the hanging‐wall block of regional‐scale faults that differ from other nearby faults by being highly reflective and penetrating to greater depths in the lower crust. Coupled thermal, mechanical, and fluid‐flow modeling supports the theory that these faults were fluid migration pathways from the lower to the upper crust. Strong reflections are also recorded from two deeply penetrating faults in the Proterozoic Mt. Isa province in northeastern Australia. Both are closely related spatially to copper and copper‐gold deposits. One, the Adelheid fault, is also adjacent to the large Mt. Isa silver‐lead‐zinc deposit. In contrast, other deeply penetrating faults that are not intrinsically reflective but are mapped in the seismic section on the basis of truncating reflections have no known mineralization. Regional seismic profiles can therefore be applied in the precompetitive area selection stage of exploration. Applying seismic techniques at the orebody scale can be difficult. Orebodies often have complex shapes and reflecting surfaces that are small compared to the diameter of the Fresnel zone for practical seismic frequencies. However, if the structures and alteration haloes around the orebodies themselves, seismic techniques may be more successful. Strong bedding‐parallel reflections were observed from the region of alteration around the Mt. Isa silver‐lead‐zinc orebodies using high‐resolution profiling. In addition, a profile in Tasmania imaged an internally nonreflective bulge within the Que Hellyer volcanics, suggesting a good location to explore for a volcanic hosted massive sulfide deposit. These case studies provide a pointer to how seismic techniques could be applied during mineral exploration, especially at depths greater than those being explored with other techniques.

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A new compilation of magnetic data over onshore and offshore Tasmania plus existing geological mapping and gravity data has provided the basis for the production of a map illustrating the geometric distribution of the main basement units that comprise Tasmania Significant items of the new interpretation map include the delineation of the widespread sub-surface granite occurrences in Tasmania, identification of more extensive occurrences of Proterozoic rocks than previously known, mapping of the extent of the Dundas Trough and extensive northwestern and southeastern continuations of the Beaconsfield ultramafics, definition of the areal distribution of Mesozoic sedimentary basins and the control of Proterozoic lineaments, in particular the Arthur Lineament, on the development of the Mesozoic basins. The use of filtering techniques to suppress the magnetic effects of shallow magnetic sources proved particularly valuable for mapping deeper structures obscured by basalt flows and dolerite dykes and sills.

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