@inproceedings{fdi:010063880,
  title = {{T}ransient hydrothermal corrugations within mineralized ultramafic laterites},
  author = {{G}uillou-{F}rottier, {L}. and {B}eauvais, {A}nicet and {B}ailly, {L}. and {W}yns, {R}. and {A}ug{\'e}, {T}. and {A}udion, {A}.{S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}ineralization processes in ultramafic laterites are partly controlled by fluid flow regimes in these porous and permeable systems. {D}uring weathering of ultramafic rocks, exothermic chemical reactions, such as hydration of olivine, may generate shallow subsurface (< 200 m) temperatures of several tens of °{C}. {T}he reaction-induced fracturing leads to further reactions and increases the permeability. {F}or more than 20 {M}yr, the peridotite massifs of {N}ew {C}aledonia have undergone intense weathering, and the observable undulations along the weathering front, attest to a corrugated bedrock topography. {C}ombined together, the excess heat (up to 70-90°{C}) and high permeability (10^-14 to 9 10^-13 m²) might have potentially triggered hydrothermal convection, as confirmed by {R}ayleigh number estimates. {T}his was numerically modeled by accounting for temperature-dependent fluid properties, and for time-dependent and spatially varying parameters simulating the deepening of the weathering front. {M}odeling the transient evolution of the thermal and flow velocity fields over 10 {M}yr reveals that hydrothermal convection can develop in the {N}ew {C}aledonian laterites, even on sloped surfaces where topography-driven flow prevails. {C}onvective cells develop above the weathering front, and the models reveal two-dimensional corrugations below which weathering is no longer efficient.},
  keywords = {{LATERITE} ; {MINERALISATION} ; {HYDROGEOLOGIE} ; {CYCLE} {BIOGEOCHIMIQUE} ; {ROCHE} {ULTRAMAFIQUE} ; {CONVECTION} {HYDROTHERMALE} ; {NOUVELLE} {CALEDONIE}},
  numero = {},
  pages = {4},
  booktitle = {{R}essources min{\'e}rales dans un monde durable},
  year = {2015},
  URL = {https://www.documentation.ird.fr/hor/fdi:010063880},
}