FindAPhD Weekly PhD Newsletter | JOIN NOW FindAPhD Weekly PhD Newsletter | JOIN NOW

This project is no longer listed on and may not be available.

Click here to search for PhD studentship opportunities
  Dr David Neave, Dr M Hartley, Dr M Polacci, Dr R Tartese  Applications accepted all year round  Self-Funded PhD Students Only

About the Project

Active volcanoes in areas of robust magmatism like mid-ocean ridges and volcanic arcs are increasingly thought to be fed from geometrically complex magma plumbing systems that extend through much of the Earth’s crust. These plumbing systems are typically considered to be dominated by solids that form coherent crystal mushes, through which melts and exsolved volatiles can percolate and sometimes coalesce to form ephemeral melt-rich bodies. However, reconstructing the structure and chemistry of crystal mushes is challenging because petrologists are typically limited to looking at either volcanic rocks in which mush textures are lost through syn-eruptive crystal disaggregation or plutonic rocks in which primary textures are modified during slow cooling. Despite recent advances in our understanding, the nature of crystal mushes beneath active volcanoes thus remains highly uncertain, which has diverse implications for understanding crustal accretion processed and the behaviour of magma plumbing systems before and during eruptions.

The main aim of this project is to reconstruct the history of an Icelandic mush zone in a region of active volcanism. By systematically investigating the textures and chemistry of large (≥10 cm) cognate xenoliths erupted in the Eastern Volcanic Zone of Iceland it will be possible to constrain both how active mushes form and respond to magmatic processes in the runup to eruption. The extensive preservation of mush textures in these xenoliths will help bridge volcanic and plutonic perspectives of crystal mush complexity and architecture, providing vital new insights into active magmatic systems.

Key activities in the project will be using scanning electron microscopy, electron probe microanalysis and laser-ablation mass spectrometry to quantitatively map crystal textures and compositions across a large number of xenoliths. This will allow variations in mush structure and mineralogy to be constrained and interpreted in terms of mush formation and disaggregation processes. Subject to the applicant’s interest, 3D xenolith textures could be investigated using X-ray computed microtomography and the timescales of mush formation and disaggregation investigated using diffusion chronometry. Although sufficient material to start this project is already in Manchester, further fieldwork will hopefully also be possible.

To make an application please do so here - 

Please then search and select PhD Earth Science (academic programme) and PhD Planetary Science (academic plan)

Funding Notes

This is a self funded project.
Please see funding opportunities here -


Hansen, H. & Grönvold, K. (2000). Plagioclase ultraphyric basalts in Iceland: The mush of the rift. Journal of Volcanology and Geothermal Research 98, 1–32.
Neave, D. A., Maclennan, J., Hartley, M. E., Edmonds, M. & Thordarson, T. (2014). Crystal storage and transfer in basaltic systems: the Skuggafjöll eruption, Iceland. Journal of Petrology 55, 2311–2346.
Cashman, K. V., Sparks, R. S. J. & Blundy, J. D. (2017). Vertically extensive and unstable magmatic systems: A unified view of igneous processes. Science 355, eaag3055.
Holness, M. B., Stock, M. J. & Geist, D. (2019). Magma chambers versus mush zones: constraining the architecture of sub-volcanic plumbing systems from microstructural analysis of crystalline enclaves. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, 20180006.

How good is research at The University of Manchester in Earth Systems and Environmental Sciences?

Research output data provided by the Research Excellence Framework (REF)

Click here to see the results for all UK universities
Search Suggestions
Search suggestions

Based on your current searches we recommend the following search filters.

PhD saved successfully
View saved PhDs