@article{fdi:010092186,
  title = {{I}nvestigating the velocity of magmatic intrusions and its relation with rock fracture toughness : insights from laboratory experiments and numerical models},
  author = {{G}aete, {A}. and {M}accaferri, {F}. and {F}urst, {S}. and {P}inel, {V}irginie},
  editor = {},
  language = {{ENG}},
  abstract = {{A} key question for those who study magmatic and volcanic processes is: '{H}ow fast can a magmatic intrusion travel?' {O}bservations and models indicate ranges between 10-2 and 1 m s-1 depending on several parameters, including magma buoyancy (or driving pressure), viscosity and rock fracture toughness ({K}c). {H}owever, {K}c values are difficult to constrain, as effective values inferred from large magmatic intrusions may be 2-3 orders of magnitude larger than measured values from small laboratory samples. {T}his can be attributed to non-elastic processes that dissipate energy at different rates, depending on factors such as the fracture dimension and fracture propagation velocity. {H}ere, we aim to investigate this aspect and provide a scheme for estimating effective fracture toughness values ({K}eff) by considering fluid-filled fracture processes across different ranges of propagation velocities. {T}o do so, we combine (i) analogue laboratory experiments involving the propagation of oil- and air-filled cracks within a solidified gelatin block, with (ii) numerical simulations, reproducing the crack shape and velocity and providing an estimate of the energy dissipated by the fluid flow between the crack walls. {W}e show that even at the scale of our experiments, {K}eff values exhibit significant variations spanning over an order of magnitude. {O}ver the velocity ranges relative to our two sets of experiments, we identify two empirical relations for an effective, velocity-dependent fracture energy (triangle {E}f (v)), showing that when such an empirical relation is implemented into the numerical model, it improves the prediction of velocities and velocity variations. {F}ollowing a similar procedure and building empirical relations for triangle {E}f (v) or {K}eff(v) at the scale of magmatic intrusions would improve predictions on dyke propagation velocities in the crust. {I}n order to do so, a considerable amount of observations on the geometry and propagation velocity of magmatic dykes should be gathered.},
  keywords = {{F}racture and flow ; {N}umerical modelling ; {E}xperimental volcanism ; {P}hysics of magma and magma bodies},
  booktitle = {},
  journal = {{G}eophysical {J}ournal {I}nternational},
  volume = {240},
  numero = {1},
  pages = {638--651},
  ISSN = {0956-540{X}},
  year = {2024},
  DOI = {10.1093/gji/ggae396},
  URL = {https://www.documentation.ird.fr/hor/fdi:010092186},
}