@article{fdi:010061256,
  title = {{A} double seismic zone in the subducting {J}uan {F}ernandez {R}idge of the {N}azca {P}late (32 degrees {S}), central {C}hile},
  author = {{M}arot, {M}. and {M}onfret, {T}ony and {P}ardo, {M}. and {R}analli, {G}. and {N}olet, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he region of central {C}hile offers a unique opportunity to study the links between the subducting {J}uan {F}ernandez {R}idge, the flat slab, the double seismic zone ({DSZ}), and the absence of modern volcanism. {H}ere we report the presence and characteristics of the first observed {DSZ} within the intermediate-depth {N}azca slab using two temporary seismic catalogs ({O}valle 1999 and {C}hile {A}rgentina {S}eismological {M}easurement {E}xperiment). {T}he lower plane of seismicity ({LP}) is located 20-25km below the upper plane, begins at 50km depth, and merges with the lower plane at 120km depth, where the slab becomes horizontal. {F}ocal mechanism analysis and stress tensor calculations indicate that the slab's state of stress is dominantly controlled by plate convergence and overriding crust thickness: {A}bove 60-70km depth, the slab is in horizontal compression, and below, it is in horizontal extension, parallel to plate convergence, which can be accounted for by vertical loading of the overriding lithosphere. {F}ocal mechanisms below 60-70km depth are strongly correlated with offshore outer rise bend faults, suggesting the reactivation of preexisting faults below this depth. {T}he large interplane distances for all {N}azca {DSZ}s can be related to the slab's unusually cold thermal structure with respect to its age. {S}ince {LP}s globally seem to mimic mantle mineral dehydration paths, we suggest that fluid migration and dehydration embrittlement provide the mechanism necessary to weaken the rock and that the stress field determines the direction of rupture.},
  keywords = {{N}azca subducting slab ; central {C}hile ; double seismic zones ; focal mechanisms ; stress tensor ; {CHILI}},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch. {S}olid {E}arth},
  volume = {118},
  numero = {7},
  pages = {3462--3475},
  ISSN = {2169-9313},
  year = {2013},
  DOI = {10.1002/jgrb.50240},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061256},
}