I currently have responsibility for the Experimental Petrology Facility and the MicroFTIR Laboratory and have been involved in developing new apparatus and analytical techniques within the BEEST group at Bristol. My geological interests are many, but the majority of experimental work has been related to the behaviour of volatile components in igneous systems. This ranges from storage and release of volatiles during melting in the mantle, right through to explosive exsolution of gas at volcanic centers. General themes have included;
Noble gas partitioning into melts during mantle melting, the relationships between radiogenic parents, daughter products and the way the Earth has degassed through time (one- versus two-layered mantle).
Mechanisms of water storage in mantle minerals and extraction during melting.
The effect of melt chemistry on volatile solubility mechanisms for Water, CO2, N2, and Noble gases (and more recently Halogens and S).
The compositional controls on carbonate-silicate immiscibility in the petrogenesis of carbonatite magmas.
Much of this work has utilized experimental observations to develop very generic theoretical models, but more recent studies with students have drawn on his broad background to investigate more specific geological problems, currently involving;
Kimberlite eruption mechanisms; explosive vs passive emplacement.
The transfer of lithophile elements by fluids released from igneous intrusions.
The subduction of volatile components via pelagic sediment
The effect of volatiles on solid phases relations in sub-volcanic magma chambers and the consequences of decompression as magmas ascend (current case studies include; Mt St Helens; Various islands in the Lesser Antilles; Uturuncu in Bolivia, The 1815 eruption of Tambora, Indonesia; Nea Kameni, Santorini; Stromboli, Italy; Erta Ale and Dabbahu, Ethiopia)