Skip to Main content Skip to Navigation
Theses

Etude géochimique des sédiments du lac de Cadagno et de la cinétique de déshydratation des stérols

Abstract : The goal of this work is to study from a geochemical point of view contemporary sediments from alpine lake Cadagno and kinetics of sterols dehydration in such an environment. Optical microscope inspection of cores sections and GC-MS analysis of biomarkers such as n-alkanes, pristane, phytane, hopanoids and steroids are used to precise conditions of lacustrine sediment deposition. Variations in sedimentation rate combined with natural events such as avalanches can well explain TOC profile measurements. Furthermore, the kinetic study shows that the selective dehydration mechanisms of sterols are controlled by bacteria and not physico-chemical processes, results which have, in a larger extent, important consequences for the geochemical study of ancient sediments. Analysis of samples of this kind dating of Middle Miocen and originated from the Monterey Formation (California, USA) allowed as well within the scope of this work to identify a new class of potential biomarkers: the 4,14-dimethylsterans.
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00214292
Contributor : Yvan Finck <>
Submitted on : Wednesday, January 23, 2008 - 8:54:22 PM
Last modification on : Wednesday, August 14, 2019 - 10:18:16 AM
Long-term archiving on: : Thursday, April 15, 2010 - 1:43:54 AM

Identifiers

  • HAL Id : tel-00214292, version 1

Citation

Yvan Finck. Etude géochimique des sédiments du lac de Cadagno et de la cinétique de déshydratation des stérols. Géochimie. University of Geneva, 2003. Français. ⟨tel-00214292⟩

Share

Metrics

Record views

308

Files downloads

1617