Productividad y oxigenación en la cuenca de panamá, pacífico colombiano, durante el pleistoceno tardío-holoceno: el registro de los foraminíferos bentónicos

Benthonic Foraminifera in the and gt; 150 µm size-fraction were analysed from the uppermost 2 m of Cores ODP677B (1.202oN-83.737oW) and TR163-38 (1.337oS-81.583oW) from the Panamá Basin, Colombian Pacific. A large seasonality in the organic carbon flux to the seafloor is suggested for Core ODP677B,...

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Autores:
Betancur, María Julliet
Martínez, Ignacio
Tipo de recurso:
Article of journal
Fecha de publicación:
2001
Institución:
Universidad Nacional de Colombia
Repositorio:
Universidad Nacional de Colombia
Idioma:
spa
OAI Identifier:
oai:repositorio.unal.edu.co:unal/42094
Acceso en línea:
https://repositorio.unal.edu.co/handle/unal/42094
http://bdigital.unal.edu.co/32191/
Palabra clave:
Geología
Ciencias de la tierra
Geociencias
Paleoceanografía
Cuaternario
Oceano Pacífico Oriental
Foraminíferos bentónicos
Oxigenación
Sistemas de surgencia
Geología
Ciencias de la tierra
Geociencias
Paleoceanography
Quaternary
Eastern Pacífic Ocean
Benthonic Foraminifera
oxygenation
upwelling systems
Rights
openAccess
License
Atribución-NoComercial 4.0 Internacional
Description
Summary:Benthonic Foraminifera in the and gt; 150 µm size-fraction were analysed from the uppermost 2 m of Cores ODP677B (1.202oN-83.737oW) and TR163-38 (1.337oS-81.583oW) from the Panamá Basin, Colombian Pacific. A large seasonality in the organic carbon flux to the seafloor is suggested for Core ODP677B, -located in the mesotrophic central Panamá Basin-, for the last 30ka. Maximum values are recorded at 10.5 y 21 ka y 25.5 Y 30.5ka. Seasonality in the organic carbon flux to the seafloor is low and homogeneous for Core TR 163-38, -located in the southern eutrophic region of the Panamá Basinexcept for dysoxic-anoxic conditions between 10.5 and 18ka (the deglaciation) when productivity was intensified. These cores do respond to a productivity latitudinal gradient with similar or lower values in the north (Core ODP677B) than today's for the last glacial. Past productivity was larger during deglaciation south of the equator (Core TR163-38). Possible mechanisms to explain these trends are: (1)intensification of the Equatorial Divergence and Peruvian upwelling systems, (2) a more efficient utilization of nutrients, (3) variations in the chemical composition of upwelling waters, and (4) migration of the Equatorial Divergence.