@article{fdi:010079746,
  title = {{F}ield observations and numerical models of a {P}leistocene-{H}olocene feeder dyke swarm associated with a fissure complex to the east of the {T}atara-{S}an {P}edro-{P}ellado complex, {S}outhern {V}olcanic {Z}one, {C}hile},
  author = {{R}uz, {J}. and {B}rowning, {J}. and {C}embrano, {J}. and {I}turrieta, {P}. and {G}erbault, {M}uriel and {S}ielfeld, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}agma is transported through the lithosphere as dykes which, during periods of unrest, may feed eruptions at the surface. {T}he propagation path of dykes is influenced by the crustal stress field and can be disturbed by crustal heterogeneities such as contrasting rock units or faults. {M}oreover, as dykes propagate, they themselves influence the surrounding stress field through processes of stress transfer, crustal deformation and seismic failure. {T}he result is the formation of arrested dykes, as well as contrasting strike and dip angles and dyke segmentation. {H}ere, we study the mechanisms of dyke injection and the role played in modifying the stress field and potential propagation paths of later dyke injections. {T}o do this we combine field data from an eroded and well-exposed shallow feeder dyke swarm with a suite of two-dimensional {FEM} numerical models. {W}e mapped 35 dyke segments over a similar to 1 km long dyke swarm exposed similar to 5 km to the {E}ast of {P}ellado {V}olcano, in the {T}atara-{S}an {P}edro-{P}ellado ({TSPP}) volcanic complex, {S}outhern {V}olcanic {Z}one of the {A}ndes. {D}etailed mapping of the swarm elucidates two preferential strike orientations, one similar to {N}80 degrees {E} and the other similar to {N}60 degrees {E}. {O}ur numerical models simulate both the {TSPP} volcanic complex and the studied dyke swarm as zones of either magmatic excess pressure or as a rigid inclusion. {T}he crustal segment hosting the volcanic complex and dykes is modelled using an elastic domain subjected to regional compression in select model cases. {M}odel outputs provide the stress and strain fields resulting from the different geometries and applied boundary loads. {T}he model results indicate that individual dyke injections can locally rotate the principal stresses such as to influence the range of orientations over which later dykes will form. {T}he orientation of sigma(1) at the dyke tip ranges over 60 degrees (+/- 30 degrees either side of the dyke tip) indicating that the strike orientation of later dykes will fall within this range. {T}he effect of adding a bulk regional compression is to locally increase the magnitude of favorably oriented tensile stresses in the bedrock but to reduce the range of sigma(1) orientations to 40 degrees (+/- 20 degrees). {T}his implies that under a far-field transpressive stress regime, as is common in {A}ndean settings, regional dyke swarms will tend to maintain their strike orientation parallel to the regional bulk stress. {T}hese results should be accounted for when studying periods of volcanic unrest in order to discern the location and orientation of potential fissure eruptions in active volcanic areas such as the {S}outhern {V}olcanic {Z}one of the {A}ndes.},
  keywords = {{D}yke propagation paths ; {S}outhern {V}olcanic {Z}one ; {N}umerical modelling ; {F}issure eruptions ; {A}rc volcanism ; {T}ranspressional convergence ; {CHILI} ; {ANDES} ; {TATARA} {SAN} {PEDRO} {PELLADO} {VOLCAN}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {404},
  numero = {},
  pages = {107033 [19 ]},
  ISSN = {0377-0273},
  year = {2020},
  DOI = {10.1016/j.jvolgeores.2020.107033},
  URL = {https://www.documentation.ird.fr/hor/fdi:010079746},
}