My overarching research focus is on the use of state-of-the-art geochemical techniques for understanding the Earth system. This principally involves combining aspects of igneous petrology, volcanology and geochemistry to understand the architecture and dynamics of sub-volcanic magma systems. Much of my work couples novel geochemical analyses with numerical models or geophysical observations. By studying rocks and minerals that have been erupted at active and dormant volcanoes in the past, I aim to identify pre-eruptive signals that might aid volcano monitoring efforts in the future.
Earth Surface Research Laboratory
I am the Director of the Earth Surface Research Laboratory (ESRL) at Trinity College. This new facility hosts a range of equipment for bulk analysis of geological materials and is supported by dedicated technical staff. The ESRL is the main analytical facility for the Tellus geochemical survey – a national programme collecting compositional data on soils and sediments across Ireland, undertaken by Geological Survey Ireland. Research projects using the laboratory include diverse topics, ranging from sedimentology and climate change to igneous petrology and environmental radiochemistry.
Galápagos magma systems
The Galápagos Archipelago is one of the most volcanically active regions on Earth and provides an ideal natural laboratory for understanding magmatic processes. My research focuses on applying novel petrological techniques to understand the architecture and dynamics of crustal magma systems. I am interested in how these crustal processes impact the timing and style of volcanic activity at the Earth’s surface and, by comparing the magmatic systems that underlie different volcanic centres across the archipelago, I hope to determine how spatial variations in mantle conditions impact the dynamics of magma ascent and eruption. My work on Galápagos would not be possible without the support of the Galápagos National Park, the Charles Darwin Foundation and the Ecuadorian Geophysical Institute. Working with colleagues at these institutions, I aim to use my results to improve civil and wildlife protection in the archipelago.
Recent Galápagos projects have involved integrating petrological techniques (e.g. mineral and melt barometers) and geophysical information (e.g. seismicity and ground deformation) to construct detailed models of sub-volcanic magma systems. I have also been investigating how the trace element concentrations in erupted crystals can be used to characterise the compositional diversity of crustal melts.
Apatite as a magmatic volatile probe
The exsolution of volatile elements provides the driving force for volcanic eruptions. However, these elements are notoriously difficult to analyse using established petrological techniques, limiting our ability to understand their pre-eruptive behaviour. I have been working to establish the use of hydrous minerals (principally apatite) as a new magmatic volatile ‘probe’. This has involved developing analytical techniques (EPMA and SIMS) and building new thermodynamic models for interpreting magmatic apatite volatile concentrations. This research has provided exciting new insights into the triggering mechanisms for major volcanic eruptions and these advances have since been widely utilised by the community.
See more of my research at:
I am accepting applications from post-graduate students. Please contact me to discuss potential opportunities.
Emma Horn (University of Southampton, UK), PhD – Using mantle cumulates as an insight into explosive volcanic eruptions and a geochemical understanding of the magma chamber below Tenerife (co-supervisor).
Helen Gildersleeves (University of Cambridge, UK), MSci – The mechanisms of crystal-melt segregation and magma chamber assembly in large silicic volcanoes (supervisor).
Gus de Falbe (University of Cambridge, UK), MSci – Constructing a temporal record of magmatic sulphur behaviour before major explosive eruptions (supervisor).
Matt Gleeson (University of Oxford, UK), MSci – Constraining magma storage conditions of peralkaline volcanic centres: a case study on Aluto (co-supervisor).
Victoria Honour (University of Oxford, UK), MSci – Possible controls on Fe-Ti-P mineralisation in the Upper Zone of the Bushveld Complex (co-supervisor).
Fundamentals of Geochemistry (Starting Semester 1 2020)
Stock, M.J., Geist, D., Neave, D.A., Gleeson, M.L.M., Bernard, B., Howard, K.A., Buisman, I., and Maclennan, J., in review. ‘Cryptic evolved melts beneath monotonous basaltic shield volcanoes in the Galápagos Archipelago’. Earth and Planetary Science Letters.
Honour, V.C., Holness, M.B., and Stock, M.J., 2019. ‘The effect of cooling rate on immiscible silicate liquid microstructure: an example from the Palaeogene dykes of Northeast England’. Mineralogical Magazine, 83, 809-820.
Vukmanovic, Z., Holness, M.B., Stock, M.J., and Roberts, R.J., 2019. ‘The creation and evolution of crystal mush in Upper Zone of the Rustenburg Layered Suite, Bushveld Complex, South Africa’. Journal of Petrology, egz038.
Bernard, B., Stock, M.J., Coppola, D., Hidalgo, S., Bagnardi, M., Gibson, S.A., Hernandez, S., Ramón, P., and Gleeson, M.L.M., 2019. ‘Chronology and phenomenology of the 1982 and 2015 Wolf volcano eruptions, Galápagos Archipelago’. Journal of Volcanology and Geothermal Research, 374, 26-38.
Woods, A.W., and Stock, M.J., 2019. ‘Some fluid mechanical constraints on crystallisation and recharge within sills’. Philosophical Transactions of the Royal Society A, 377.
Holness, M.B., Stock, M.J., and Geist, D., 2019. ‘Magma chambers vs mush zones: constraining the architecture of sub-volcanic plumbing systems from microstructural analysis of crystalline enclaves’. Philosophical Transactions of the Royal Society A, 377.
Campbell, L.S., Giordano, G., Stock, M.J., Langella, A., Bish, D.L., and Gatta, G.D., 2019. ‘Reconstruction of residual melts from the zeolitized explosive products of alkaline-mafic volcanoes’. American Mineralogist, 104, 2-16.
Stock, M.J., Bagnardi, M., Neave, D.A., Maclennan, J., Bernard, B., Buisman, I., Gleeson, M.L.M., and Geist, D., 2018. ‘Integrated petrological and geophysical constraints on magma system architecture in the western Galápagos Archipelago: insights from Wolf volcano’. Geochemistry, Geophysics, Geosystems, 19, 4722– 4743.
Astbury, R.L., Petrelli, M., Ubide, T., Stock, M.J., Arienzo, I., D’Antonio, M., and Perugini, D., 2018. ‘Tracking plumbing system dynamics at the Campi Flegrei caldera, Italy: High-resolution trace element mapping of the Astroni crystal cargo’. Lithos, 318, 464-477.
Stock, M.J., Humphreys, M.C.S., Smith, V.C., Pyle, D.M., and Isaia, R., 2018. ‘Tracking crustal-scale volatile behaviour in sub-volcanic plumbing systems: insights into pre-eruptive processes at Campi Flegrei, Italy’. Journal of Petrology, 59, 2463–2492.
Gleeson, M.L.M., Stock M.J., Pyle, D.M., Mather, T.A., Hutchinson, W., Yirgu, G., and Wade, J., 2017. ‘Constraining magma storage conditions at a restless volcano in the Main Ethiopian Rift using phase equilibria models’. Journal of Volcanology and Geothermal Research, 337, 44-61.
Stock, M.J., Humphreys, M.C.S., Smith, V.C., Isaia, R., and Pyle, D.M., 2016. ‘Late-stage volatile saturation as a potential trigger for explosive volcanic eruptions’. Nature Geoscience, 9, 249-254.
Scott, J.A.J., Humphreys, M.C.S., Mather, T.A., Pyle, D.M., and Stock, M.J., 2015. ‘Insights into the behaviour of S, F, and Cl at Santiaguito Volcano, Guatemala, from apatite and glass’. Lithos, 232, 375-394.
Stock, M.J., Humphreys, M.C.S., Smith, V.C., Johnson, R.D., Pyle, D.M., and EIMF, 2015. ‘New constraints on electron-beam induced halogen migration in apatite’. American Mineralogist, 100, 281-293.
James, R.H., Green, D.R.H., Stock, M.J., Alker, B.J., Banerjee, N.R., Cole, C., German, C.R., Huvenne, V.A.I., Powell, A.M., and Connelly, D.P., 2014. ‘Composition of hydrothermal fluids and mineralogy of associated chimney material on the East Scotia Ridge back-arc spreading centre’. Geochimica et Cosmochimica Acta, 139, 47-71.
Chew, D.M., Donelick, R.A., Donelick, M.B., Kamber, B.S., and Stock, M.J., 2013. ‘Apatite chlorine concentration measurements by LA-ICP-MS’. Geostandards and Geoanalytical Research, 38, 23-35.
Stock, M.J., Taylor, R.N., and Gernon, T.M., 2012. ‘Triggering of major eruptions recorded by actively forming cumulates’. Scientific Reports, 2, 731.