Cool early Albian climates; new data from Argentina

Previous studies on the stable isotope geochemistry of dimitobelid belemnites from Antarctica and Australia indicated cool climatic conditions during the early Albian in the shelf seas around the Gondwanan margin. In this paper new analyses from diagenetically unaltered specimens of Dimitobelus cf....

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Detalhes bibliográficos
Autores: Pirrie, D., Marshall, J. D., Doyle, P., Riccardi, Alberto Carlos
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/99795
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/99795
Access Level:acceso abierto
Palavra-chave:Ciencias Naturales
Albian
Palaeoclimates
Argentina
Dimitobelid belemnites
Descrição
Resumo:Previous studies on the stable isotope geochemistry of dimitobelid belemnites from Antarctica and Australia indicated cool climatic conditions during the early Albian in the shelf seas around the Gondwanan margin. In this paper new analyses from diagenetically unaltered specimens of Dimitobelus cf. stimulus from early Albian deposits of the Rio Mayer Formation of Lago San Martin, southern Argentina are presented. Oxygen isotope values for diagenetically least altered samples give values ranging between d18O C0.07 and C0.96 vPDB, which equate to a mean palaeotemperature of 9.5 (C (assuming dw of 1.2& SMOW). These data are consistent with a model of cool early Albian shelf seas in the Southern Hemisphere.