@article{fdi:010077945,
  title = {{M}odelling the riverine delta {L}i-7 variability throughout the {A}mazon {B}asin},
  author = {{M}affre, {P}. and {G}odderis, {Y}. and {V}igier, {N}. and {M}oquet, {J}. {S}. and {C}arretier, {S}{\'e}bastien},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he present study investigates the processes controlling the elementary and isotopic cycle of the lithium over the {A}mazon basin. {A} numerical model is developed to simulate two major processes that have been proposed as key controls of the river lithium isotopic composition: weathering reactions inside the regolith, accounting for secondary phase formation, and interactions between riverine water and secondary phases in floodplain. {B}oth processes generate fractionation of lithium isotopes ("batch" fractionation and "{R}ayleigh" distillation respectively) that potentially control the riverine isotopic composition of the {A}mazon and its tributaries. {A} study of the model parameters shows that two different regimes are impacting the lithium isotopic composition of the rivers within the {A}mazon catchment. {I}n the {S}outh ({M}adeira and its tributaries), the lithium isotopic signature of river waters can be explained by lithium release and fractionation during weathering reactions in the regolith, followed by "{R}ayleigh distillation" in the floodplain increasing progressively the lithium isotopic composition, in agreement with a previously published hypothesis. {I}n contrast, the lithium isotopic composition of rivers located in the northern part of the {A}mazon watershed ({S}olimoes and tributaries) cannot be simulated by the model assuming the same processes than in the southern part. {M}odel optimization suggests than the nature of the material being eroded and weathered is important. {I}n the {N}orth, fresh source rocks of volcanic origin releases large amount of {L}i and promotes rapid smectite precipitation, allowing the riverine delta {L}i-7 to rise before flowing through floodplains. {T}his result suggests that the environments able to generate high riverine delta {L}i-7 (higher than 25 parts per thousand) are complex and not firmly identified yet.},
  keywords = {{L}ithium isotopes ; {W}eathering ; {A}mazon ; {M}odel ; {AMAZONE} {BASSIN}},
  booktitle = {},
  journal = {{C}hemical {G}eology},
  volume = {532},
  numero = {},
  pages = {119336 [17 ]},
  ISSN = {0009-2541},
  year = {2020},
  DOI = {10.1016/j.chemgeo.2019.119336},
  URL = {https://www.documentation.ird.fr/hor/fdi:010077945},
}