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We are seeking a high quality student to apply for an International Research Scholarship at Monash University. ‘Pressure Solution’ is one of the most fundamental phenomenon occurring in the Earth. It has been implicated in the slip frequency of earthquakes, diagenesis, lithification, cleavage formation, the liberation and accumulation of gold in quartz veins and the generation of stylolites. The physics underlying pressure solution may possibly have implications for the majority of metamorphic and hydothermal alteration reactions through the coupled dissolution-replacement mechanism. Historically, pressure solution has been attributed to high inter-grain contact stresses reducing the chemical potential energy for the dissolution reaction. However, recent experiments have identified an ‘electrochemical-like’ mechanism of pressure solution that sheds light upon the importance of mineral dissimilarity in the pressure solution process. Specifically, these experiments demonstrated that the enhancement of the silica dissolution rate was much higher than can be attributed to a purely ‘pressure’ effect (experiments were run at just 2-3 atms of contact pressure). The observed enhanced silica dissolution rates appear to be driven by the strength (and orientation) of an interfacial electric field which naturally develops when two dissimilarly charged surfaces are pressed together. This project will both investigate natural examples of pressure solution such as stylolites, and use the field observations to unravel the fundamental physics of the process by performing electrochemical pressure solution experiments with a newly developed Atomic Force Microscope (AFM) system. The nano-scale resolution and ability to generate pressures in the GPa regime permits this system to replicate ‘real-world’ conditions and observe dissolution processes occurring on geological time-scales. The student will get to design and lead experiments to investigate the impact of fluid chemistry, pH, mineralogy and contact pressure. This is a collaborative project between Monash and Deakin universities, in the vibrant and cosmopolitan city of Melbourne. Monash consistently ranks as one of Australia's top G8 universities. In order to be considered competitive the student must have a first class Honours qualification from a well-recognised university, or a Masters qualification with 1-2 publications in internationally recognised journals. Respond directly to [log in to unmask] and NOT this list. Regards, Steven Micklethwaite (School of Earth, Atmosphere and Environment) Wren Greene (Institute for Frontier Materials, Deakin University) ######################################################################## To unsubscribe from the GEO-TECTONICS list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=GEO-TECTONICS&A=1