Workshop "Marginal plateaus"
Workshop "Marginal plateaus : from magmatic divergent margins to transform margins, and from the continental shelf to the pelagic and contouritic setting"
Grenoble (France) - November 28-29th, 2017
magmatic divergent margins, transform margins, post-rift subsidence, contourites
Marginal plateaus can be defined in the submarine morphology as flat (sub-horizontal) but deep (deeper than the shelf break) domains within the continental slope (Mercier de Lépinay et al., 2016). They occur in all passive margins, but are mainly located at the junction between diachroneous ocean basins.
These structures were classically considered as remnants of rifted margins, underlain by a thinned continental crust. However, they appear closely related to magmatic rifted margins and Seaward Dipping Reflectors. They are also systematically bounded by a transform margin. Forming prominent salients along the continental margin, they influence the deep-sea circulation, leading to contouritic sedimentation.
Both the polyphased tectonic and subsidence evolution, and the sedimentary setting controlled by deep currents, make the marginal plateaus a specific target for continental margin understanding and hydrocarbon exploration.
Based on recent data acquisition (e.g. Demerara plateau offshore French Guiana and Suriname), the aims of the workshop are to compare the numerous marginal plateaus in the world, and to bring together specialists from different Earth science fields, in order to investigate :
- The nature of the basement (thinned continental crust, magmatic crust) and how it was deformed or emplaced,
- The relationships between marginal plateaus, hot spots and magmatic divergent margins,
- The structure of transform margins that are associated with marginal plateaus,
- The control of inherited structures on the polyphased evolution of those domains,
- The evolution of subsidence (and uplift), from the initial magmatic rifting to the secondary rift stage and transform opening, and, finally, to the post-rift sag stage,
- The influence of the topography of marginal plateaus on the local and global circulation of intermediate and deep oceanic waters,
- The specific sedimentary systems that develop in those deep-current dominated settings.
► Keynote speakers
- Lies Loncke – University Perpignan, France : Marginal plateaus : definition and scientific challenges
- Walter Roest – IFREMER, Brest, France : An overview of the scientific exploration of the Demerara plateau
- Asbjorn Breivik – University of Oslo, Norway : Why is the Vøring Plateau a plateau ?
- Gavin Elliott – Lukoil, United Kingdom : An overview of the Hatton-Rockall plateau
- Dave McCarthy – British Geological Survey, Edinbourgh, United Kingdom : The Falkland plateau
- Arne Døssing – Technical University of Denmark : The Alpha ridge
- Scott Bryan – Queensland University, Brisbane, Australia : Large ignous provinces, continental break-up and marginal plateaus
- Christophe Basile – University Grenoble-Alpes, France :Transform margins along marginal plateaus
- Javier Hernandez-Molina – Royal Holloway University, London, United Kingdom : Contourite terraces vs marginal platforms : conceptual implications
We welcome contributions on all topics related to marginal plateaus, either based on case studies, on synthetic studies or on modelisation. If you want to make a presentation (likely oral, but posters are also welcomed) or just attend, please send an email to christophe.basile univ-grenoble-alpes.fr
- September the 22th to propose a presentation (oral or poster)
- October the 6th to send an abstract
- October the 27th to attend the meeting without presentation
► Practical information
The workshop will be held in english
Location and date : Grenoble (France), November 28-29th 2017
No fees, but pre-registration is mandatory
Mail : christophe.basile univ-grenoble-alpes.fr
Tel : +334 76 51 40 69
Adress : ISTerre, 1381 rue de la Piscine
38400 St Martin d’Hères – France
►The organization committee
Christophe Basile (ISTerre, Université Grenoble-Alpes)
Lies Loncke (CEPHREM, University Perpignan)
Walter Roest (IFREMER, Brest)
David Graindorge (University Brest)