@article{fdi:010079015,
  title = {{K}aolinite dating from {A}crisol and {F}erralsol: {A} new key to understanding the landscape evolution in {NW} {A}mazonia ({B}razil)},
  author = {{M}athian, {M}. and {B}ueno, {G}. {T}. and {B}alan, {E}. and {F}ritsch, {E}mmanuel and {D}o {N}ascimento, {N}. {R}. and {S}elo, {M}. and {A}llard, {T}.},
  editor = {},
  language = {{ENG}},
  abstract = {{F}erralsols and {A}crisols are major types of soils of the {A}mazon basin observed on various landform units comprising plateau surfaces, incised hills at their edges and slopes. {T}he present study focuses on an {A}crisol developed on plateaus surfaces from northwest {A}mazonia and a {F}erralsol from the convex hills of the incised plateau edges. {L}ocal geomorphologic models of weathering covers suggest that {F}erralsols are younger than plateau {A}crisols but the absolute chronology of their formation is still lacking. {T}his type of information is however critical to understand the evolution of northwest {A}mazon {B}asin landscapes and to identify its link with major climatic and geomorphologic events. {I}n this article, kaolinite-rich samples from soils and saprolites belonging to a transect in the {S}ao {G}abriel da {C}achoeira region ({A}mazon state, {B}rasil) are investigated. {B}ased on their crystal-chemical characters, several types of kaolinites are identified. {U}sing a previously developed methodology based on electron paramagnetic resonance ({EPR}) spectroscopy, crystallization ages are proposed for these different kaolinites. {S}aprolite kaolinites are dated from 6 to 3.6 {M}a in the {A}crisol profile and display significantly more recent ages ( < 1 {M}a) in the {F}erralsol saprolite. {K}aolinite from solum (soils horizons above the {C} horizon) display ages ranging from 2.5 to 1 {M}a for both the {A}crisol and {F}erralsol. {T}hree distinct weathering stages are thus unraveled by kaolinite dating. {T}he {A}crisol saprolite displays the older weathering stage preserved in the investigated soil sequence. {I}t is followed by a single weathering stage leading to the formation of both soils. {T}hese two stages can be correlated to the formation of two paleosurfaces recognized at the scale of the {S}outh {A}merica subcontinent as the {M}iocene {V}ehlas and the {Q}uaternary {P}araguacu surfaces, indicating that the {C}uricuriari profiles evolved during periods favorable to tropical weathering surfaces development in {A}mazonia. {T}he last weathering stage corresponds to the saprolite formation in the {F}erralsol profile, which is still developing under the present {A}mazonian climate. {T}his still active, late weathering stage is tentatively related to the more significant drainage and relief dissection occurring on the plateau edges.},
  keywords = {{L}aterite ; {EPR} dating ; {K}aolinite ; {F}erralsol/{A}crisol transition ; {A}mazonia ; {BRESIL} ; {AMAZONIE}},
  booktitle = {},
  journal = {{G}eoderma},
  volume = {370},
  numero = {},
  pages = {art. 114354 [18 p.]},
  ISSN = {0016-7061},
  year = {2020},
  DOI = {10.1016/j.geoderma.2020.114354},
  URL = {https://www.documentation.ird.fr/hor/fdi:010079015},
}