Mineral physics of icy planetary bodies

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The outer solar system contains a large number of ice-rich objects, ranging in size from a few km to a few thousand km across; the latter includes the Jovian satellites Ganymede and Callisto and the Saturnian moon Titan, each of which are larger than the planet Mercury. It has been recognised for many decades that the 'ice' portion of these large icy bodies will have inherited additional volatile and non-volatile constituents from their 'dirty snowball' accretionary precursors and will also have undergone substantial hydrothermal processing during core differentiation. The result of this is that the 'ice' layers will contain a range of hydrate compounds as 'rock-forming minerals'. However, it is only in the last 20 years that experimental and computational mineral physics methods have provided the tools to determine the behaviour of these materials under the relevant conditions of pressure and temperature (0 < P < 5 GPa, 100 < T < 400 K). Such work is essential to ensure an accurate basis for structural and evolutionary modelling, which in turn provides the means of interpreting observational data from remote and in situ planetary exploration.The aim of this studentship is to address long-standing problems in the structure and properties of high-pressure hydrate minerals, synthesising and recovering high-P polymorphs or dissociation products of materials such as meridianiite (MgSO4.11H2O), mirabilite (Na2SO4.10H2O), ammonia dihydrate (NH3.2H2O) and various sulfuric acid hydrates (H2SO4.nH2O).