Les iguanodons de Bernissart: leur évolution diagénétique et les processus de dégradation
type: CreativeWork
description: About thirty complete articulated skeletons of iguanodons have been excavated from Bernissart. This unique collection is conserved at the RBINS. The bones excavated were the object of diverse physical and chemical treatments to protect them from their degradation. These bones were not the object of detailed mineralogical analyses allowing to understand either diagenetic mechanisms involved or to understand the specific mechanisms of their change. This work thus aims at filling this lack. It integrates petrographic (POM, SEM), mineralogical (DRX, Raman Spectroscopy) and chemical (EDS, X-ray fluorescence, microprobe) techniques. By these methods, 30 different minerals were identified. The diagenesis of Iguanodon bones is the result of cumulative physical, chemical and biological processes that will modify the original chemical and/or structural properties of this organic object. Bone diagenesis is a complex process that includes the degradation of organic matter, the dissolution and recrystallization of bone apatite, the enrichment in trace elements, the precipitation of new minerals in the bone cavities (permineralisation), the fracturation process. A plan is proposed positioning in a relative timescale minerals formed during 3 diagenetic stages and the degradation processes engaged following the bones exhumation. During burial variable recrystallisation took place: the slightly crystallized carbonated hydroxylapatite (the mineral phase of fresh bone tissue) was replaced by well crystallized carbonated fluorapatite currently present in the Iguanodon bones. Whereas some minerals infiltrated in the bone during cavity filling by the sediment (“mainly” quartz, “argillaceous” phyllosilicates), others are authigenic and precipitated in the cavities during burial (pyrite, barite, sphalerite, celestine, iron oxi-hydroxides, authigenic apatite, calcium sulfate and to a lesser extent vivianite). Pyrite is the most abundant authigenic mineral in the Iguanodon fossil bones. It o…
abstract: About thirty complete articulated skeletons of iguanodons have been excavated from Bernissart. This unique collection is conserved at the RBINS. The bones excavated were the object of diverse physical and chemical treatments to protect them from their degradation. These bones were not the object of detailed mineralogical analyses allowing to understand either diagenetic mechanisms involved or to understand the specific mechanisms of their change. This work thus aims at filling this lack. It integrates petrographic (POM, SEM), mineralogical (DRX, Raman Spectroscopy) and chemical (EDS, X-ray fluorescence, microprobe) techniques. By these methods, 30 different minerals were identified. The diagenesis of Iguanodon bones is the result of cumulative physical, chemical and biological processes that will modify the original chemical and/or structural properties of this organic object. Bone diagenesis is a complex process that includes the degradation of organic matter, the dissolution and recrystallization of bone apatite, the enrichment in trace elements, the precipitation of new minerals in the bone cavities (permineralisation), the fracturation process. A plan is proposed positioning in a relative timescale minerals formed during 3 diagenetic stages and the degradation processes engaged following the bones exhumation. During burial variable recrystallisation took place: the slightly crystallized carbonated hydroxylapatite (the mineral phase of fresh bone tissue) was replaced by well crystallized carbonated fluorapatite currently present in the Iguanodon bones. Whereas some minerals infiltrated in the bone during cavity filling by the sediment (“mainly” quartz, “argillaceous” phyllosilicates), others are authigenic and precipitated in the cavities during burial (pyrite, barite, sphalerite, celestine, iron oxi-hydroxides, authigenic apatite, calcium sulfate and to a lesser extent vivianite). Pyrite is the most abundant authigenic mineral in the Iguanodon fossil bones. It o…
author: Leduc, Thierry
language: fr
keywords: iguanodon, diagenesis, oxidation, pyrite, sulphate, fracturing, conservation, Physical, chemical, mathematical & earth Sciences, Earth sciences & physical geography, Physique, chimie, mathématiques & sciences de la terre, Sciences de la terre & géographie physique
license: http://purl.org/coar/access_right/c_abf2
date published: 2012-09-25
date modified: 2026-07-24T02:49:20Z
provider: Université de Liège
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: ULiège - Université de Liège