- 1CNR-ISSMC, Faenza, Italy (emilycharlotte.bamber@issmc.cnr.it)
- 2School of Science and Technology, Geology Division, University of Camerino, Camerino, Italy
- 3Istituto Nazionale di Geofisica e Vulcanologia - Osservatorio Etneo, Sezione di Catania, Catania, Italy
- 4Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
- 5Department of Medical Physics and Biomedical Engineering, University College London, London, UK
- 6Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
- 7Department of Materials, Slovenian National Building and Civil Engineering Institute (ZAG), Ljubljana, Slovenia
- 8Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, Pisa, Italy
- 9Department of Materials, The University of Manchester, Manchester, UK
- 10School of Engineering, The University of Liverpool, Liverpool, UK
- 11School of Earth Sciences, University of Bristol, Bristol, UK
- 12Department of Earth Sciences, University of Turin, Turin, Italy
- 13Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany
The explosivity of a volcanic eruption is controlled by several interdependent processes during magma ascent, such as crystallisation, gas exsolution and outgassing. Syn-eruptive crystallisation can increase the potential of magma fragmentation. Whilst the degree of coupling between the gas and melt phases during ascent can influence eruptive style. Quantitative textural analysis of vesicles and crystals in erupted products can provide insight into syn-eruptive conduit processes and the conditions leading to magma fragmentation. Synchrotron-based imaging techniques such as X-ray computed micro-tomography can provide information on vesicle and crystal size, shape and their spatial distribution in 3D. Furthermore, X-ray ptychography, an X-ray microscopy technique with nanoscale resolution, can be used to expand this 3D textural analysis to nanoscale crystals in volcanic rocks.
Here, we present a 3D reconstruction and quantification of vesicle and crystal textures in pyroclasts of the Masaya Triple Layer eruption, a highly explosive Plinian eruption of Masaya caldera, Nicaragua. Images and observations of vesicle textures at the micro-scale were acquired using X-ray computed micro-tomography and used to reconstruct the geometrical properties of the connected pore network, including connectivity, tortuosity and the throat-pore size ratio. X-ray ptychography was used to perform a 3D textural analysis of nanoscale crystals within the groundmass of clasts. These data were used to reconstruct conduit processes and evaluate the impact of syn-eruptive crystallisation, vesiculation and outgassing on magma rheology and fragmentation. Our results provide insight into the driving mechanisms of highly explosive, basaltic Plinian activity, and also highlight the potential of using multi-scale 3D imaging techniques to analyse textural features in pyroclasts and investigate controls on eruptive style.
How to cite: Bamber, E. C., Arzilli, F., La Spina, G., Polacci, M., Cipiccia, S., Batey, D. J., Mancini, L., de' Michieli Vitturi, M., Gholinia, A., Bagshaw, H., Di Genova, D., Brooker, R., Andronico, D., Corsaro, R. A., Giordano, D., Valdivia, P., and Burton, M. R.: 3D micro and nano-scale imaging of bubbles and crystals in volcanic rocks: Implications for magma rheology and ascent dynamics of highly explosive basaltic eruptions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12553, https://doi.org/10.5194/egusphere-egu25-12553, 2025.
