View in EDS

Sedimentary processes and cold-water coral mini-mounds at the Ferrol canyon head, NW Iberian margin.

Saved in:
Bibliographic Details
Title: Sedimentary processes and cold-water coral mini-mounds at the Ferrol canyon head, NW Iberian margin.
Authors: Collart, Tim1 tim.collart@ugent.be, Verreydt, Wencke1, Hernández-Molina, F. Javier1, Llave, Estefanía1, León, Ricardo1, Gómez-Ballesteros, María1, Pons-Branchu, Edwige1, Stewart, Heather1, Van Rooij, David1
Source: Progress in Oceanography. Dec2018, Vol. 169, p48-65. 18p.
Subjects: Deep-sea corals, Bottom water (Oceanography), Sedimentary basins, Marine sediments, Habitat destruction
Abstract: Highlights • Sedimentary processes in the Ferrol canyon head are affected by bottom currents. • Bottom currents result from MOW and internal tide interaction with the canyon head. • Relict CWC mini-mounds occur upslope from favourable conditions in the canyon head. • Pockmarks provided preferential colonization surfaces for CWC mini-mound initiation. • An early Holocene shift of the ENACW-MOW interface is proposed based on CWC mini-mounds. Abstract The western Iberian margin has a complex morphology controlled by both geological and oceanographic processes. Compared to the submarine canyons in the southern part of this margin (e.g. Nazaré and Setubal), the canyons in the northern part (e.g. Ferrol and A Coruña) have received little attention. This study maps the geomorphological features around the Ferrol canyon head and combines them with oceanographic observations to infer the sedimentary and oceanographic processes active in this area. Furthermore, the occurrence of a cold-water coral (CWC) mini-mound province near the canyon head and the Ortegal Spur pockmark field is investigated with regard to seepage processes, oceanographic conditions and anthropogenic impact. The Ferrol canyon head and outer Ortegal Spur are characterized by erosional (erosional and abraded surfaces, contourite channels and furrows), depositional (contourite drifts and sediment waves) and mixed (contourite terrace) features, indicating a dominant control of bottom currents on the sedimentary processes. Bottom currents are related to the interaction of the canyon head topography with both the Mediterranean Outflow Water (MOW) slope current and with M2 internal tides associated to the interface (pycnocline) between Eastern North Atlantic Central Water (ENACW) and MOW. Due to this interaction, the Ferrol canyon head is subject to active sediment resuspension and forms a potential source area for the intermediate nepheloid layers along the NW Iberian upper slope. The CWC mini-mounds (1.9–2.7 m high and 75–141 m in diameter) occur between 400 and 560 m depth. Seismic facies signatures indicative of fluid-flow and morphometric analysis implies that larger CWC mini-mounds adjacent to the pockmark field initiated by colonization of pre-existing pockmarks, while smaller more clustered mounds developed independently. The observed mini-mounds are relict features likely related to their position outside of the contemporary ENACW-MOW interface which favours CWC growth through (1) increased bottom currents, enhancing food supply and (2) the presence of a potential density envelope σ θ = 27.35–27.65 kg/m3, proposed to control coral larvae transport along the NE Atlantic margin. Alternatively, the lack of contemporary coral growth might be related to habitat destruction by bottom trawling. However, a preliminary age constraint reveals CWC growth occurred during the early Holocene, coeval to relict CWC mini-mounds near canyon heads on the Armorican margin. Their existence suggests a regional shift in the NE Atlantic density profile where the ENACW-MOW interface occurred up to 200 m above its contemporary position. [ABSTRACT FROM AUTHOR]
Copyright of Progress in Oceanography is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 133439561
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Sedimentary processes and cold-water coral mini-mounds at the Ferrol canyon head, NW Iberian margin.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Collart%2C+Tim%22">Collart, Tim</searchLink><relatesTo>1</relatesTo><i> tim.collart@ugent.be</i><br /><searchLink fieldCode="AR" term="%22Verreydt%2C+Wencke%22">Verreydt, Wencke</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Hernández-Molina%2C+F%2E+Javier%22">Hernández-Molina, F. Javier</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Llave%2C+Estefanía%22">Llave, Estefanía</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22León%2C+Ricardo%22">León, Ricardo</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Gómez-Ballesteros%2C+María%22">Gómez-Ballesteros, María</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Pons-Branchu%2C+Edwige%22">Pons-Branchu, Edwige</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Stewart%2C+Heather%22">Stewart, Heather</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Van+Rooij%2C+David%22">Van Rooij, David</searchLink><relatesTo>1</relatesTo>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Progress+in+Oceanography%22">Progress in Oceanography</searchLink>. Dec2018, Vol. 169, p48-65. 18p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Deep-sea+corals%22">Deep-sea corals</searchLink><br /><searchLink fieldCode="DE" term="%22Bottom+water+%28Oceanography%29%22">Bottom water (Oceanography)</searchLink><br /><searchLink fieldCode="DE" term="%22Sedimentary+basins%22">Sedimentary basins</searchLink><br /><searchLink fieldCode="DE" term="%22Marine+sediments%22">Marine sediments</searchLink><br /><searchLink fieldCode="DE" term="%22Habitat+destruction%22">Habitat destruction</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Highlights • Sedimentary processes in the Ferrol canyon head are affected by bottom currents. • Bottom currents result from MOW and internal tide interaction with the canyon head. • Relict CWC mini-mounds occur upslope from favourable conditions in the canyon head. • Pockmarks provided preferential colonization surfaces for CWC mini-mound initiation. • An early Holocene shift of the ENACW-MOW interface is proposed based on CWC mini-mounds. Abstract The western Iberian margin has a complex morphology controlled by both geological and oceanographic processes. Compared to the submarine canyons in the southern part of this margin (e.g. Nazaré and Setubal), the canyons in the northern part (e.g. Ferrol and A Coruña) have received little attention. This study maps the geomorphological features around the Ferrol canyon head and combines them with oceanographic observations to infer the sedimentary and oceanographic processes active in this area. Furthermore, the occurrence of a cold-water coral (CWC) mini-mound province near the canyon head and the Ortegal Spur pockmark field is investigated with regard to seepage processes, oceanographic conditions and anthropogenic impact. The Ferrol canyon head and outer Ortegal Spur are characterized by erosional (erosional and abraded surfaces, contourite channels and furrows), depositional (contourite drifts and sediment waves) and mixed (contourite terrace) features, indicating a dominant control of bottom currents on the sedimentary processes. Bottom currents are related to the interaction of the canyon head topography with both the Mediterranean Outflow Water (MOW) slope current and with M2 internal tides associated to the interface (pycnocline) between Eastern North Atlantic Central Water (ENACW) and MOW. Due to this interaction, the Ferrol canyon head is subject to active sediment resuspension and forms a potential source area for the intermediate nepheloid layers along the NW Iberian upper slope. The CWC mini-mounds (1.9–2.7 m high and 75–141 m in diameter) occur between 400 and 560 m depth. Seismic facies signatures indicative of fluid-flow and morphometric analysis implies that larger CWC mini-mounds adjacent to the pockmark field initiated by colonization of pre-existing pockmarks, while smaller more clustered mounds developed independently. The observed mini-mounds are relict features likely related to their position outside of the contemporary ENACW-MOW interface which favours CWC growth through (1) increased bottom currents, enhancing food supply and (2) the presence of a potential density envelope σ θ = 27.35–27.65 kg/m3, proposed to control coral larvae transport along the NE Atlantic margin. Alternatively, the lack of contemporary coral growth might be related to habitat destruction by bottom trawling. However, a preliminary age constraint reveals CWC growth occurred during the early Holocene, coeval to relict CWC mini-mounds near canyon heads on the Armorican margin. Their existence suggests a regional shift in the NE Atlantic density profile where the ENACW-MOW interface occurred up to 200 m above its contemporary position. [ABSTRACT FROM AUTHOR]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Progress in Oceanography is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=133439561
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.pocean.2018.02.027
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 18
        StartPage: 48
    Subjects:
      – SubjectFull: Deep-sea corals
        Type: general
      – SubjectFull: Bottom water (Oceanography)
        Type: general
      – SubjectFull: Sedimentary basins
        Type: general
      – SubjectFull: Marine sediments
        Type: general
      – SubjectFull: Habitat destruction
        Type: general
    Titles:
      – TitleFull: Sedimentary processes and cold-water coral mini-mounds at the Ferrol canyon head, NW Iberian margin.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Collart, Tim
      – PersonEntity:
          Name:
            NameFull: Verreydt, Wencke
      – PersonEntity:
          Name:
            NameFull: Hernández-Molina, F. Javier
      – PersonEntity:
          Name:
            NameFull: Llave, Estefanía
      – PersonEntity:
          Name:
            NameFull: León, Ricardo
      – PersonEntity:
          Name:
            NameFull: Gómez-Ballesteros, María
      – PersonEntity:
          Name:
            NameFull: Pons-Branchu, Edwige
      – PersonEntity:
          Name:
            NameFull: Stewart, Heather
      – PersonEntity:
          Name:
            NameFull: Van Rooij, David
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 12
              Text: Dec2018
              Type: published
              Y: 2018
          Identifiers:
            – Type: issn-print
              Value: 00796611
          Numbering:
            – Type: volume
              Value: 169
          Titles:
            – TitleFull: Progress in Oceanography
              Type: main
ResultId 1