Darwin-Bernissart meeting, Date: 2009/02/09 - 2009/02/13, Location: RBINS, Brussels

Publication date: 2009-01-01
Pages: 100 -

Tribute to Charles Darwin and Bernissart Iguanodons: New Perspectives on Vertebrate Evolution and Early Cretaceous Ecosystems

Author:

Yans, J
Andreu, B ; Baele, JM ; Cornet, C ; De Riqcles, A ; Dejax, J ; Dupuis, C ; Galbrun, B ; Gerards, T ; Gerrienne, P ; Godefroit, P ; Gomez, B ; Gosselin, R ; Leduc, T ; Petit, G ; Pons, D ; Preat, A ; Robaszynski, F ; Schnyder, J ; Smith, T ; Spagna, P ; Steurbaut, Etienne ; Taverne, L ; Tshibangu, JP ; Van Itterbeeck, Jimmy ; Vandycke, S ; Vanneste, C

Keywords:

Bernissart, natural pit, Wealden facies, Mons basin, boreholes

Abstract:

Three new boreholes have been drilled within and around the natural pit ("Cran") of Bernissart in 2002- 2003. They provided exceptional material used for a multidisciplinary research to improve our knowledge of the Iguanodons-bearing Wealden facies. The BER3 borehole reached 349.95 meters of Thanetian, Late Cretaceous, Early Cretaceous and Westphalian sediments. Below 8 meters of green sandy clays it cuts 67 meters of Late Cretaceous chalks and marls with local glauconites and cherts. The Albian and Cenomanian "meule" sediments lie between 75 and 265 meters. The Wealden facies trapped in the "Cran aux iguanodons" of Bernissart are recognised between 265 and 315 meters. The latter are laminated dark pyritic clays with mm-thick brown and white silty levels. The borehole ends within a breccia with Carboniferous blocks between 315 and 349.95 meters. Several topics were investigated such as palynolgy and determination of woody and plant-mesofossils fragments, to detail the age and paleoenvironments of the Iguanodons. The formation processes of the "Cran" were documented by multidisciplinary approach, i.e sedimentology of the lacustrine Wealden facies (including clay mineralogy, granulometry and magnetic susceptibility), characterization of the organic matter with Rock-eval, palynofacies, soluble alkane content, carbon isotope and structural analysis. Paleontological content was also studied by palaeohistology and diagenesis of the bone fragments, characterization of amber, preparations for diatoms and ostracods analyses (barren). Moreover, Wealden facies from IRSNB collection (historical searches of 1878-1881) and other sites in the Mons basin (Hautrage, Thieu, Baudour) were also investigated, notably for their content of numerous fishes and coprolites. In Hautrage and Baudour, we note the discovery of teeth of freshwater sharks and a shinbone of a juvenile sauropod. In Thieu the occurrence of dinoflagellate cysts suggests the marine influence for the Wealden facies in the Eastern part of the Mons basin.