@article{fdi:010066974,
  title = {{A}n alternative model for the formation of hydrous {M}g/{N}i layer silicates ('deweylite'/'garnierite') in faulted peridotites of {N}ew {C}aledonia: {I}. {T}exture and mineralogy of a paragenetic succession of silicate infillings},
  author = {{F}ritsch, {E}mmanuel and {J}uillot, {F}arid and {D}ublet, {G}. and {F}onteneau, {L}ionel and {F}andeur, {D}. and {M}artin, {E}. and {C}aner, {L}. and {A}uzende, {A}. {L}. and {G}rauby, {O}. and {B}eaufort, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{D}etailed textural and mineralogical investigations carried out in mineralized veins of the {N}ew {C}aledonian peridotites reveal three major periods of infilling and alteration closely linked to post-obduction tectonic activity. {T}he first two periods of infillings are related to the alteration of hydrothermal serpentines, mostly found in the thick serpentine network of the peridotites, into fine-grained serpentine-like residues and newly formed talc-like minerals of weak but variable swelling capacity. {T}he alteration of serpentine into talc-like minerals is limited during the first period of infilling and almost completed during the second one. {I}n some fault zones of the {N}ew {C}aledonian peridotites, talc-like minerals are replaced by sepiolite. {S}uch alterations are reported in both the {N}i-free and {N}i-rich zones of the infillings (i.e. in the white 'deweylite' and greenish 'garnierite' of the fault zones, respectively). {T}hey led to the individualization of the hydrous {M}g/{N}i silicate ore, which is nowadays found in fractures of the saprock and saprolite units of thick lateritic profiles. {T}he third and last period of infilling is assigned to the accumulation of silica and crystallization of quartz. {T}his succession of clay minerals (serpentine-like and talc-like minerals, sepiolite) and quartz in the infillings is interpreted as the result of sequential exportation of {M}g and redistribution of {N}i along the reactivated faults, generating periods of increasing {S}i activity in solutions. {I}n this paragenetic model, the meteoric water infiltrating repeatedly the permeable network created by post-obduction tectonic activity would have interacted with a low-temperature hydrothermal field following the exhumation and cooling of the ophiolite nappe. {I}n the less permeable parts of the fault network, restricted leaching conditions would have generated greater alkalinity in solutions and therefore favored the crystallization of sepiolite instead of finely divided talc-like minerals.},
  keywords = {{F}aulted peridotites ; serpentines ; {N}i-laterites ; hydrous {M}g/{N}i layer ; silicates (deweylite and garnierite) ; serpentine-like and talc-like ; minerals ; sepiolite ; {NOUVELLE} {CALEDONIE}},
  booktitle = {},
  journal = {{E}uropean {J}ournal of {M}ineralogy},
  volume = {28},
  numero = {2},
  pages = {295--311},
  ISSN = {0935-1221},
  year = {2016},
  DOI = {10.1127/ejm/2015/0027-2503},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066974},
}