@article{fdi:010040665,
  title = {{I}nheritance vs. neoformation of kaolinite during lateritic soil formation : {A} case study in the middle {A}mazon basin},
  author = {{B}alan, {E}tienne and {F}ritsch, {E}mmanuel and {A}llard, {T}. and {C}alas, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he tropical weathering of sedimentary kaolin deposits from the plateaux surrounding {M}anaus ({A}lter do {C}hao formation, {A}mazon basin, {B}razil) leads to the in situ formation of thick kaolinitic soils. {T}he structural changes of kaolinite have been investigated quantitatively by infrared spectroscopy and electron paramagnetic resonance. {B}oth techniques consistently show that each sample contains two types of kaolinite in various proportions. {T}he progressive decrease in kaolinite order from the bottom to the top of the profile results from the gradual replacement of an old population of well-ordered kaolinite, typical of the underlying sedimentary kaolin, by a more recent generation of poorly ordered soil kaolinite. {T}he vertical pattern of kaolinite replacement differs from that of the transformation of {F}e oxides and oxyhydroxides previously observed in the same profile. {T}he inherited fraction of well-ordered kaolinite ranges from 60% at a depth of 9 in to 30% in the upper levels of the soil. {T}he persistence of sedimentary kaolinite in the upper horizons suggests that the rate of kaolinite transformation is relatively slow at the time scale of lateritic soil formation. {K}aolinite inheritance unlocks the lateritic record of past weathering conditions.},
  keywords = {disorder ; {EPR} ; infrared ; kaolinite ; laterite},
  booktitle = {},
  journal = {{C}lays and {C}lay {M}inerals},
  volume = {55},
  numero = {3},
  pages = {253--259},
  ISSN = {0009-8604},
  year = {2007},
  DOI = {10.1346/{CCMN}.2007.0550303},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040665},
}