Statistical and numerical analysis of dike sequences

Dike intrusions play a fundamental role in magma transport and crustal accretion at divergent plate boundaries, where extension is accommodated through episodic sequences of magmatic intrusions, faults and fissures. However, the physical mechanisms controlling dike volumes, propagation patterns, and the evolution of these sequences remain poorly understood. This thesis investigates the scaling properties of dike sequences and explores the underlying physical processes through complementary statistical and numerical approaches. My statistical analysis extends previous work by incorporating a substantially larger dataset of dike volumes from both central volcanic edifices and divergent plate boundaries. Power-law distributions provide a good fit to the volume distributions of both settings, while differences in the fitted parameters indicate distinct statistical characteristics. The combined dataset also exhibits a bimodal distribution, suggesting that different volcano-tectonic conditions may influence dike volume distributions. To investigate the physical mechanisms responsible for these observations, I developed a numerical model to simulate dike propagation and emplacement, building on previous works. The model was applied to observed dike sequences, including Krafla (1975--1984) and Svartsengi (2023--2025). I used this model to investigate the conditions favoring sequences as opposed to single-dike episodes. The simulations reproduce the overall behaviour and emplacement positions of the modelled sequences, particularly for the initial and largest intrusions, although limitations in the representation of stress distribution and dike opening affect the results. Overall, this work highlights the potential of integrating statistical analysis and numerical modelling to investigate the controls on dike emplacement. The results suggest that stress conditions, magma supply, and the volcano-tectonic setting all contribute to the evolution of dike sequences.