Publications des scientifiques de l'IRD

Boussafir M., Sifeddine Abdelfettah, Jacob J., Foudi M., Cordeiro R. C., Albuquerque A. L. S., Abrao J. J., Turcq Bruno. (2012). Petrographical and geochemical study of modern lacustrine sedimentary organic matter (Lagoa do Caco, Maranao, Brazil) : relationship between early diagenesis, organic sedimentation and lacustrine filling. Organic Geochemistry, 47, p. 88-98. ISSN 0146-6380.

Titre du document
Petrographical and geochemical study of modern lacustrine sedimentary organic matter (Lagoa do Caco, Maranao, Brazil) : relationship between early diagenesis, organic sedimentation and lacustrine filling
Année de publication
2012
Type de document
Article référencé dans le Web of Science WOS:000304853300009
Auteurs
Boussafir M., Sifeddine Abdelfettah, Jacob J., Foudi M., Cordeiro R. C., Albuquerque A. L. S., Abrao J. J., Turcq Bruno
Source
Organic Geochemistry, 2012, 47, p. 88-98 ISSN 0146-6380
Lagoa do Caco is an equatorial lake in northeast Brazil, where the Inter-Tropical Convergence Zone (ITCZ) enters the South American continent, and so at a key position for deciphering Quaternary climatic variation. Preliminary results have shown that the sedimentary organic matter (OM) in the lake records the shifts in the ITCZ since the Last Glacial Maximum. The nature and fate of the OM have been determined by studying surface sediments and potential OM sources. We present here the results of organic petrographic and Rock-Eval pyrolysis assessments of the biological origin and preservation state of the OM in modern sediments from two deep transects of the lake. The results led us to understand how an oligotrophic lake has accumulated 6 m of OM-rich sediment during the last 20 kyr. Palaeoenvironmental studies have shown that the lake level fluctuated during this time. Our results explain the influence of lake bathymetric variation on early diagenesis and enable interpretation of the corresponding sedimentary OM record, which is dependent on the bathymetric variation.
Plan de classement
Géologie et formations superficielles [064]
Localisation
Fonds IRD [F B010055945]
Identifiant IRD
fdi:010055945
Contact