Data/hora: 26/07/2024 22:41:47

Provedor de dados: 	Institutional Archive of Ifreme (ArchiMer)	
País: 	France	
Título: 	Hydrodynamic behaviour of Nummulites: implications for depositional models	
Autores: 	Jorry, Stephan; Hasler, Ca; Davaud, E.	
Data: 	2006-05	
Ano: 	2006	
Palavras-chave: 	Carbonates; Eocene; Large benthic foraminifera; Test density; Taphocoenosis.	
Resumo: 	Large benthic foraminifers are considered to be good indicators of shallow marine carbonate environments in fossil series. Over the last 50 years, the palaeoenvironment of Tertiary Nummulites accumulations has been a matter of debate, particularly because of difficulties in interpreting these deposits, and in this way, the absence of analogues in present-day seas does not help. The aim of this paper is to insight the different ways Nummulites tests and clasts may accumulate according to their hydrodynamic behaviour. Based on experimental measurements and on SEM observations, it appears that the high primary skeletal porosity of Nummulites made them easily transportable. The calculated threshold shear velocities confirm that large-sized Nummulites can be moved by weak wave-driven currents. This peculiar hydrodynamic behaviour of Nummulites could explain the diversity of depositional models. Depending on local hydrodynamic conditions, autochthonous Nummulites deposits can be preserved as in situ winnowed bioaccumulations or be accumulated offshore, onshore or alongshore, away from the original biotope.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/00085/19597/17234.pdf

DOI:10.1007/s10347-005-0035-z	
Editor: 	Springer	
Relação: 	http://archimer.ifremer.fr/doc/00085/19597/	
Formato: 	application/pdf	
Fonte: 	Facies (0172-9179) (Springer), 2006-05 , Vol. 52 , N. 2 , P. 221-235	
Fonte: 	Springer-Verlag 2005