Pleistocene calcareous macro-and-microfossils from the southernmost tip of South America as environmental proxies during the last interglacial period

Macro-and-microfossils, including molluscs, cirripeds, echinoids, foraminifers and ostracods area significant component of a Pleistocene marine unit located along the southern coast of the BeagleChannel, on Navarino Island, Chile. This paleontological record represents the richest and most diversemac...

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Detalles Bibliográficos
Autores: Gordillo, Sandra, Cusminsky, Gabriela Catalina, Bernasconi, Emiliana, Ponce, Juan Federico, Rabassa, Jorge Oscar, Pino, Mario
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/129616
Acceso en línea:http://hdl.handle.net/11336/129616
Access Level:acceso abierto
Palabra clave:Pleistocene
Southernmost South America
Marine Mollusks
Last Interglacial
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descripción
Sumario:Macro-and-microfossils, including molluscs, cirripeds, echinoids, foraminifers and ostracods area significant component of a Pleistocene marine unit located along the southern coast of the BeagleChannel, on Navarino Island, Chile. This paleontological record represents the richest and most diversemacro-and-micro assemblage recovered from Pleistocene southern South America. In total, 97 taxa wereidentified: 34 molluscs, 57 foraminifers, and 6 ostracods. They comprise a mixture of specimensinhabiting shallow marine environments characterized by strong bottom currents and belonging todifferent local communities associated with the spatial heterogeneity in this basin. The taxonomiccomposition of this paleofauna shows remarkable similarities with present-day fauna, indicating thatboth groups developed under similar environmental conditions. However, slight different climaticconditions at the age of deposition cannot be ruled out. As well, an ecosystem transition towards a trulymarine environment with high number of taxa was recognized. Finally, a Hiatella-cirriped assemblagedeserves special attention since the polymorphic shell of fossil and living Hiatella is used as a paleo-environmental tool. In this regard, the small size of Hiatella in the studied marine unit is best related toits mode of life as a nestler within empty tests of barnacles, which apparently served as microenvi-ronments for this species. Nevertheless, more geochemical data on living and fossil Hiatella shells fromthe Beagle Channel will be necessary to test the suitability of using this species to evaluate paleo-temperatures and other sea water variations during the Quaternary.