Sean Whitley

Biography

I graduated from Keele University in 2015 with a First Class honours in MGeoscience. My third year dissertation introduced me to using geochemical analysis to understand the evolution of the Borrowdale volcanics of the English Lake District, which led to my undergraduate Masters thesis where I used geochemistry and multiple quantitative modelling techniques to constrain the geochemical evolution of Furnas Volcano in the Azorean plateau. These works won multiple awards and confirmed that further research is the direction I wish to continue in.

I subsequently continued my studies at Keele University in 2015, starting a PhD entitled “Xenoliths as tracers of magmatic and intra-crustal processes at subduction zone volcanoes”. This project aims to use petrological, geochemical, SEM, microthermometric and quantitative modelling techniques to investigate magmatic and intra-crustal processes occurring in subduction zones, with primary focus on the Aeolian (Italy), Hellenic (Greece) and Sunda (Indonesia) arcs.

Awards

• 2015: NSGGA John Myers Award. Runner up best Masters Project
• 2014: NSGGA John Myers Award. Best undergraduate dissertation
• 2013: Petroleum Exploration Society of Great Britain Young Persons (PESGB YP) Undergraduate Mapping Sponsorship

Affiliations

The Mineralogical Society of Great Britain and Ireland

Research and scholarship

Project:

Xenoliths as tracers of magmatic and intra-crustal processes at subduction zone volcanoes

Supervisors: Dr Ralf Halama (lead supervisor), Dr Ralf Gertisser.

 Xenoliths (ancient Greek: “foreign rocks”) are fragments of older, pre-existing rocks brought up from great depths to the Earth’s surface by volcanic eruptions. They are often found as inclusions in volcanic rocks and can provide crucial information about magma generation processes, magma storage conditions, crustal structure and magma-crust interaction. In addition, xenoliths hold important clues to understand how volcanoes work and what processes determine their eruptive behaviour, ultimately contributing to a better evaluation of associated volcanic hazards.

Despite their significance, few studies have used xenoliths to address these important and timely scientific issues. This cutting-edge project sets out to fill this gap by focusing on two types of xenoliths common in the eruptive products of subduction zone volcanoes:

1.) Plutonic (cumulate) xenoliths: They record the evolution of magma during transfer from the mantle through the crust and provide constraints on the architecture of volcanic magma plumbing systems (e.g. Beard, 1986; Stamper et al., 2014).

2.) Crustal xenoliths: They represent snapshots of reactions between magma and crustal rocks at various depth allowing insights into the crustal structure of volcanic arcs and processes of magma-crust interaction (e.g. Chadwick et al., 2007; Markl, 2005).

The project will concentrate on xenolith-bearing samples from the Aeolian arc (Italy), the Hellenic arc (Greece) and the Sunda arc (Indonesia) that comprise a great diversity in terms of rock types and compositions. Petrographic, Scanning Electron Microscopy (SEM), ICP-MS, electron microprobe and fluid inclusion analyses will be carried out to determine textural/compositional constraints and pressure-temperature conditions of formation. These data will be used for quantitative modelling of magmatic and intra-crustal processes and conditions.

References

Beard, J.S. (1986): Geology 14: 848-851; Chadwick, J.P., et al. (2007): Journal of Petrology 48: 1793-1812; Markl, G. (2005): Contributions to Mineralogy and Petrology 149: 196-215; Stamper, C.C., et al. (2014): Journal of Petrology 55: 1353-1387.