- Lancaster University, Lancaster Environment Centre, Lancaster, United Kingdom of Great Britain – England, Scotland, Wales (a.p.mitchell@lancaster.ac.uk)
Volcano deformation can be a key signal of volcanic unrest and often precedes an eruption. Understanding the relationship between magmatic intrusions and subsequent deformation is crucial for predicting temporal and spatial eruption patterns and thus reducing the impacts of volcanic hazards by enhancing preparedness.
Laboratory analogue models enable the direct study of model volcano subsurface changes. A 2D experimental approach enables subsurface intrusions to be tracked through time and directly compared to the surface displacements. In this study, golden syrup, a viscous fluid, was injected as a magma analogue into a cone-shaped granular material representing an analogue edifice. Images were taken to capture the time-series evolution of the intrusions and associated deformation. The relationship between subsurface intrusions and subsequent surface deformation was investigated by analysing the frame-by-frame pixel displacements using Particle Image Velocimetry (PIV).
Initial findings indicated that the internal compaction of granular material accommodated the radial deformation resulting from the intrusions. Transitions to surface displacement correlated with increased strain rate from the intrusions. Material cohesion influenced material compaction; injections into high cohesion material produced surface deformation when the intrusion approached near-surface regions, compared to injections into low cohesion material (that produced surface deformation when the intrusion was deeper). These findings highlight the role of material (host rock) strength in accommodating deformation via compaction.
In the experiments, an “eruption” occurred when the golden syrup breached the surface of the analogue edifice, and this terminated the experiment. The extrusion location was consistent for each experiment and occurred along the edges of the deforming section at the surface. This finding may improve our ability to locate eruption locations based on surface deformation patterns, enhancing preparedness for deforming volcanoes and their potential eruption location.
How to cite: Mitchell, A., Lane, S., Gilbert, J., Tuffen, H., and James, M.: Analogue Modelling of Intrusion Dynamics in Relation to Internal and Surface Deformation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10571, https://doi.org/10.5194/egusphere-egu25-10571, 2025.
