Secondary flow in contour currents controls the formation of moat-drift contourite systems

Ocean currents control seafloor morphology and the transport of sediments, organic carbon, nutrients, and pollutants in deep-water environments. A better connection between sedimentary deposits formed by bottom currents (contourites) and hydrodynamics is necessary to improve reconstructions of paleo...

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Detalles Bibliográficos
Autores: Wilckens, Henriette, Eggenhuisen, Joris T., Adema, Pelle H., Hernández-Molina, Francisco J., Jacinto, Ricardo Silva, Miramontes, Elda
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/346270
Acceso en línea:http://hdl.handle.net/10261/346270
Access Level:acceso abierto
Palabra clave:Contourite
Hydrodynamics
Nutrient
Organic carbon
Paleocurrent
Seafloor
Secondary flow
Sediment transport
Descripción
Sumario:Ocean currents control seafloor morphology and the transport of sediments, organic carbon, nutrients, and pollutants in deep-water environments. A better connection between sedimentary deposits formed by bottom currents (contourites) and hydrodynamics is necessary to improve reconstructions of paleocurrent and sediment transport pathways. Here we use physical modeling in a three-dimensional flume tank to analyse the morphology and hydrodynamics of a self-emerging contourite system. The sedimentary features that developed on a flat surface parallel to a slope are an elongated depression (moat) and an associated sediment accumulation (drift). The moat-drift system can only form in the presence of a secondary flow near the seafloor that transports sediment from the slope toward the drift. The secondary flow increases with higher speeds and steeper slopes, leading to steeper adjacent drifts. This study shows how bottom currents shape the morphology of the moat-drift system and highlights their potential to estimate paleo-ocean current strength.