Steady and transient flows around banks located near a shelf edge

Gjevik, B.; Moe, Halvard

doi:10.1016/0278-4343(94)90055-8

Cited by 15 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Between these two water bodies is a third narrow layer called the Norwegian Sea Arctic Intermediate Water (Blindheim, 1990). Winds and air pressure modi¢es the Norwegian Atlantic Current o¡ the coast while tidal currents dominate near the coast and inside the fjords (Gjevik & Moe, 1994). It covers the heavier Atlantic Water as a wedge which is thickest near the coast.…”

Section: Hydrographymentioning

confidence: 99%

“…Current directions and velocities are controlled both by the Norwegian Atlantic Current and by the semi-diurnal tidal current. Winds and air pressure modi¢es the Norwegian Atlantic Current o¡ the coast while tidal currents dominate near the coast and inside the fjords (Gjevik & Moe, 1994). Ridges, breaks and sounds locally increase the current velocity near the bottom.…”

Section: Hydrographymentioning

confidence: 99%

See 1 more Smart Citation

Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics

et al. 2001

View full text Add to dashboard Cite

This paper presents results on the distribution, abundance, and size of Lophelia pertusa coral reefs in mid-Norway (62830 H^6 5830 H N) as compiled from own investigations, earlier scienti¢c reports, reports from ¢shery surveys and ¢shermen. Detailed bathymetrical mapping covering an area of $ 600 km 2 along the Halten gas-pipeline, and two nearby areas across the shelf revealed 70 Lophelia reefs. In general, the reefs occurred close to breaks and escarpments. High densities of up to nine reefs per km 2 were found in areas with a rugged seabed topography and with a slope 40.68. These seabed features have probably positive in£uence on the transport and concentration of food particles and thus control the local distribution of Lophelia. The area covered by individual reefs varied between 1230 m 2 and 37,310 m 2 with a mean of 5628 m 2 . The height of the reefs was positively correlated with the area. Reefs 510,000 m 2 had a circular outline, while larger reefs were elongate, aligned parallel to the depth contours. Along the pipeline the average density of Lophelia reefs was 0.09 km 72 which indicates that the total number of reefs is $ 6300, covering $ 35 km 2 within the whole study area.

show abstract

Section: Hydrographymentioning

confidence: 99%

Section: Hydrographymentioning

confidence: 99%

Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics

et al. 2001

View full text Add to dashboard Cite

show abstract

“…Erosion by contour currents is normally associated with increased bathymetry gradients. The profile with detailed interpretation of such features shown by Brekke [2000] is also located at the transition between the Vøring and the Møre basins, an area which even today is associated with steep bathymetry and pronounced contour current activity [Gjevik and Moe, 1994]. In this discussion of using Miocene erosion and/or nondeposition as a paleowater depth indicator, also the Trøndelag Platform can be used as an example.…”

Section: Alternative Modelsmentioning

confidence: 99%

Differential loading by prograding sedimentary wedges on continental margins: An arch‐forming mechanism

et al. 2003

View full text Add to dashboard Cite

[1] Rapid deposition of prograding sedimentary wedges on continental margins will cause excess pore pressure, fluid flow, and compaction as they load the substratum. They may also cause faulting and structural deformation in the sedimentary succession below and in front of the load. Large depositional units are in addition associated with pronounced isostatic subsidence. The magnitude and effects each component has on the basin as a whole is often debated. To address this problem, we use a quantitative approach with a coupled hydromechanical mathematical model based on linear isotropic elasticity. The equations are solved by the finite element method (FEM). In the modeling, a wedgeshaped load emplaced successively over a period of 1.5 Myr is used to simulate the progradation of a thick sedimentary wedge. Results show that the differential load generates excess pressure below the prograding depocenter with lateral fluid flow in front and a tail of draining pore pressure behind. The sediments are pushed downward and laterally in front of the wedge and vertical and horizontal compressional and shear stresses are generated below the wedge. The formation of the Helland Hansen Arch, located in the Vøring Basin off mid-Norway, is genetically associated with differential loading. Our results indicate that the whole eastern flank of the arch is a result of differential loading, whereas the western flank is mainly related to thermal subsidence since Paleogene times. Thus, alternative explanations like intraplate stress seem to be irrelevant as a genetic mechanism.

show abstract

“…the Maelstrom region (Gjevik et al 1997)) are formed in these regions. In addition, in coastal areas, the existence of shallow banks and headlands can significantly influence the tidal flows (Gjevik and Moe 1994), and as shown by Orre et al (2006), this has an appreciable effect upon particle dispersion which has implications in pollution studies. Again these problems suggest the need for enhanced resolution in regions of rapidly changing topography.…”

Section: Introductionmentioning

confidence: 98%

Modelling the influence of small-scale effects upon the larger scale: an oceanographic challenge

2010

View full text Add to dashboard Cite

The problem of resolving or parameterising small-scale processes in oceanographic models and the extent to which small-scale effects influence the large scale are briefly discussed and illustrated for a number of cases. For tides and surges in near-shore regions, the advantages of using a graded mesh to resolve coastal and estuarine small-scale features are demonstrated in terms of a west coast of Britain unstructured mesh model. The effect of mesh resolution upon the accuracy of the overall solution is illustrated in terms of a finite element model of the Irish Sea and Mersey estuary. For baroclinic motion at high Froude number, the effect of resolving small-scale topography within a non-hydrostatic model is illustrated in terms of tidally induced mixing at a single sill, or two closely spaced sills. The question of how to parameterise small-scale nonlinear interaction processes that lead to significant mixing, in a form suitable for coarser grid hydrostatic models, is briefly considered. In addition, the importance of topographically induced mixing that occurs in the oceanic lateral boundary layer, namely, the shelf edge upon the large-scale ocean circulation is discussed together with the implications for coarse grid oceanic climate models. The use of unstructured grids in these models to enhance resolution in shelf-edge regions in a similar manner to that used in storm surge models to enhance near coastal resolution is suggested as a suitable "way forward" in large-scale ocean circulation modelling.

show abstract

Steady and transient flows around banks located near a shelf edge

Cited by 15 publications

References 13 publications

Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics

Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics

Differential loading by prograding sedimentary wedges on continental margins: An arch‐forming mechanism

Modelling the influence of small-scale effects upon the larger scale: an oceanographic challenge

Contact Info

Product

Resources

About