Sulphides - Economically important geochemical messengers from the mantle

My project is aimed at understanding how a number of economically and geologically important chemical elements partition themselves between the silicates of the outer parts of the Earth and sulphides, minerals and liquids rich in sulphur. Although sulphur is not very abundant in the Earth, it has a powerful impact on the behaviour of a wide range of elements in Earth's crust and underlying mantle. For example, the majority of ore bodies rich in nickel, copper, gold and platinum are sulphides. Many of them are formed when sulphides separate from molten silicates in volcanic areas. A principal aim of my project is to experimentally reproduce the conditions under which sulphides separate and to determine how they extract the economically important elements from the host volcanic rocks. A second aim is to use my experimental results to determine whether or not a large mass of sulphide was extracted from the molten earth early in its history (4500 million years ago) and dissolved into the metallic core.
In order to study how elements are distributed into sulphide I perform experiments at high pressures and temperatures, typically 15000 atmospheres pressure and 1400 degrees C in a large hydraulic press. After treatment at high pressure and temperature, the samples (typically about 1x1x1 millimeters) are rapidly cooled to room temperature and pressure and examined using a range of microanalytical techniques. The latter enables me to resolve chemical composition on the scale of 10 microns (or 10 millionth's of a meter).

We know very little about the origin of our planet, how it has evolved through time and how it came to be suitable for life. The key questions about the evolution of the Earth involve its first hundred million years after the accretion and concern the potential collision with the large body - the Impactor (that formed the Moon) and the late-stage bombardment of the Earth by smaller bodies that added to the Earth's mantle up to 1% of its mass. Interestingly, although they are fundamental science questions of relevance to everyone, we lack sufficient data that would enable us to evaluate these hypotheses quantitatively.
Public interest in the evolution of our planet has never been higher, issues such as climate change, solar activity, missions to planets and life on Mars attract high levels of interest and publicity. This interest emphasises the value of research that can help us understand our planet better and the need for that research to be communicated to the public and potential users. Better understanding of how the planet works has significant impacts on people's lives, including potential tools for volcanic eruptions and earthquake prediction, preventive measures against environmental catastrophes and general improvement of the quality of life.
Apart from scientific benefits, data that this project will provide could be widely used by economic geologists in order to target potential sites for magmatic sulphide deposits and to assess the concentrations of valuable trace metals, such as the platinum group elements, which are used in automotive, agriculture, chemical, petroleum, electrical, electronic, dental, medical, and aerospace industries. My study of sulphide-silicate partitioning will enable quantification of the relationship between valuable metal depletions and the extent of sulphide precipitation. Given that the host rock for the ores is silicate, the ore metals depletions in the silicates are controlled by the amounts of sulphide generated. This will make it possible to quantify the economic potential of the deposit.
Dissemination of relevant research results can be done by engaging with interdisciplinary organisations (within the University of Oxford) such as the James Martin School for the 21st Century, which promotes interaction with policy groups, as well as the education of non-scientists of all ages. Routine dissemination of research output from the fellowship will include the publication of peer reviewed scientific papers as well as the presentation of research results at international conferences and smaller, more specialised meetings. Internally (within the University of Oxford) scientific outputs from the project will be used in the development of material for Departmental, Divisional and University Science Open Days and outreach efforts at the University of Oxford, aimed both at the local community and potential new students.
The University of Oxford has a highly effective press office, with one officer dedicated to the work of the mathematical, physical and life science division (which includes Earth Sciences). The Oxford science press officer also runs the Oxford Science Blog, which has a wide reach (including a Facebook presence) and aims to communicate to the public, via the Internet, current research outputs by University of Oxford researchers. The University of Oxford is now also part of i-Tunes U, with considerable potential for the dissemination of material to the global public in the form of downloads and podcasts.
The experimental petrology group in the university of Oxford has its own webpage, which includes not only its recent achievements, but scientific tools and calculators which could be used by members of the other universities. Currently, the link to this website comes second when "experimental petrology" is searched in Google. This provides a high level of the website daily attendance.