Once subducted oceanic crustal material has been processed in the subduction zone environment, it is likely subducted into the deeper, convecting mantle as eclogite, the high-pressure form of basalt. Eventually this material may be incorporated into the mantle source regions of some erupted magmas. For example the geochemistry of some oceanic island basalts has been interpreted to suggest that discrete bodies of eclogite or pyroxenite in peridotite-dominated mantle, partially melted at high pressures and contributed to the lavas that erupted at the surface.

The recycling of elements through convergent plate boundaries strongly influences the chemical differentiation of Earth. It is widely accepted that hydrous fluid sourced from dehydrating subducting crust promotes melting in the mantle wedge and the formation of arc magmas.

Australia is wonderfully rich in mineral resources (Fe, coal, gas, gold, etc) that are so vital to our economy, and at the same time worryingly scarce in other resources vital to our welfare (groundwater). The projects outlined below use field observations, experimental data and modelling to determine the physical and chemical processes ultimately controlling the formation and management of the resources available to our nation.

Internal motions in the mantle are fundamental drivers of crustal geology and the evolution of the planet.  The mantle flows by convection, which is driven by sinking tectonic plates and rising mantle plumes.  Research topics include detailed numerical and laboratory modelling of mantle convection, including subduction and plumes, and the thermal and geochemical evolution of the mantle.  The work complements work in geochronology and geochemistry, seismology, tectonics and subduction zones.  It is also relevant to hazards from earthquakes and tsunamis.

Research in mathematical and computational geophysics is primarily focused on development of new data analysis techniques and their application across the Earth Sciences. For example the ability to extract reliable information on Earth structure from seismic data, e.g. travel times or digital waveforms, or other classes of data, depends on methods of inverse theory. Fully non-linear (stochastic) inversion methods can provide valuable insight into the character of the solution. This work has application across the Earth Sciences and particularly in the area of seismic imaging of the Earth interior.

Work in seismology and Mathematical Geophysics covers a variety of studies using wave propagation processes to study the nature of the Earth. The many strands of the research combine field observations, computer modelling, inversion and extensive data analysis to exploit the favourable location of Australia for seismic studies.