23-25 September 2013
GEOMAR East shore
Europe/Berlin timezone
Home > Timetable > Session details > Contribution details
PDF | XML | iCal

On the origin of submarine mass movements on the continental slope offshore Lofoten, northern Norway - a multi-disciplinary approach

Presented by Mrs. Nicole Jeanne BAETEN on 23 Sep 2013 from 17:15 to 19:15
Type: Poster presentation
Session: Poster session

Content

Different styles of smaller-scale mass movements characterise the continental slope offshore Lofoten, northern Norway. We use a multi-disciplinary approach to evaluate their origin as well as the present-day stability of the area, by combining morphological, sedimentological, geotechnical and geophysical data, complemented with slope stability modelling. The mass movements occur in water depths between 1100 and 2500 m and have volumes of 0.06-8.7 cubic kilometers. The instabilities are interpreted as translational slides involving spreading and multi-phase retrogression and have glide planes between 12.5-130 mbsf. Data from a sediment core shows that the shallowest style of mass movement (12.5 mbsf) was initiated within contouritic sediments characterized by high sensitivities and water contents. These sediments overlie a plumite interval characterized by dilative behaviour with pore pressure decrease with increasing shear strain and high undrained shear strength. The interface between these units acted as the basal glide plane, with deformation of the overlying sediments during slab spreading. Numerical modelling shows that the present-day continental slope is essentially stable, and allows reconstruction of the instability process initiated by an external trigger. The mass movement are probably triggered by undercutting and removal of support at the foot of the slope due to larger-scale mass movements that have occurred immediately south of the study area, including the Trænadjupet or Nyk Slides.

Place

Location: GEOMAR East shore
Address: Wischhofstr. 1-3 / D-24148 Kiel
Room: Lithothek

Primary authors

More

Co-authors

More