Foraminiferal paleodiversity and paleoenvironments at the NE coastal plain of Buenos Aires province (Argentina) during the Mid-Holocene sea level highstand

In this investigation, we carried out a Mid-Holocene paleoenvironmental reconstruction based on fossilized benthic foraminifera, retrieved from sedimentary deposits located in Bahía Samborombón coastal plain. A total of 38 species, grouped into 19 genera, were identified. The assemblage, constituted...

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Detalles Bibliográficos
Autores: Ballesteros Prada, Angélica María, Luengo, Mariel Samanta, Vilanova, Isabel, Fucks, Enrique Eduardo, Bernasconi, Emiliana
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/132928
Acceso en línea:http://hdl.handle.net/11336/132928
Access Level:acceso abierto
Palabra clave:BENTHIC FORAMINIFERA
MID-HOLOCENE
PALEOENVIRONMENTAL CHANGES
SEA LEVEL HIGHSTAND
https://purl.org/becyt/ford/1.7
https://purl.org/becyt/ford/1
Descripción
Sumario:In this investigation, we carried out a Mid-Holocene paleoenvironmental reconstruction based on fossilized benthic foraminifera, retrieved from sedimentary deposits located in Bahía Samborombón coastal plain. A total of 38 species, grouped into 19 genera, were identified. The assemblage, constituted mainly by Buccella peruviana (d’Orbigny), Cribroelphidium poeyanum (d’Orbigny), Ammonia parkinsoniana (d’Orbigny) and Ammonia tepida (Cushman), indicate predominantly abnormal marine conditions, characterized by low oxygen levels between ca. 6880–6640 and 5600–5430 yrs cal. BP. During this interval, a quantitative analysis carried out on the assemblages as well as indexes suggest found three different paleoenvironments. The first one, occurring ca. 6880–6640 yrs cal. BP, was a brackish environment with low oxygenation levels and low bottom energy. Then, ca. 6500–6250 yrs cal. BP, an environment with more marine influence, increased oxygen levels and higher energy prevailed. This higher oxygenation could be related to the flow of seawater into the area during the Mid-Holocene sea-level highstand. The third paleoenvironment developed ca. 5590–5430 yrs cal. BP, was under a gradual transition back to a brackish environment with low oxygen levels as well as low energy.