Oct 1, 2019 · Recently acquired multibeam echosounder data from the shallowest part (26–53 m depth) of Spitsbergenbanken in the western Barents Sea reveal a variety of bedforms, including megaripples, sandwaves and sandbanks.

In the North Sea, they are found on portions of flat seabed or occur superimposed on larger dunes of generally 100–800 m wavelength with amplitudes up to 17 m, here referred to as sand waves [Terwindt, 1971; Passchier, 2004]. Bed forms occur as two-dimensional (2-D) and three-dimensional forms (3-D).

Dec 17, 2005 · Sand waves with superimposed megaripples are common observations in acoustic surveys of continental shelves, including the North Sea [Terwindt, 1971]; ripples are usually too small to be observed on multibeam and side-scan sonar records.

Two sites were selected in the North Sea: a coastal site (1770*1625m) in an area with shoreface-connected ridges with 14-18 m waterdepths 6-8 km offshore southwest of IJmuiden and a site...

Apr 1, 2004 · In the respective areas, megaripples crests are parallel and under a 20º angle to sandwave crests and vary little and strongly in appearance and orientation over the length of the sandwave.

Feb 11, 2025 · Megaripples (Bellec et al., 2019) are meters to several tens of meters long and can migrate quickly (about 0.5 meter per day). These mobile bedforms have a significant impact on sediment transport, but also on the necessity (and required depth) to bury cables in the seabed.

Apr 1, 2004 · Various types of megaripples on the North Sea shoreface and inner shelf were mapped with sonar and multibeam imaging (data reported herein and in Passchier & Kleinhans, this volume). The term...

Jan 9, 2025 · Due to the recent developments in offshore wind, unique data sets have become available for wind farms in the North Sea. These data sets consist of bathymetries of high resolution in space (0.5 m) and time (several tracks surveyed repeatedly within several months; see Figs. 1 and 2).

Wave megaripples, with N-S crest orientation, mostly occur on low lying areas, while bottom current megaripples occur on high and low areas. Two main crest orientations are observed: NW-SE (the most common) and NE-SW. The lunate/lingoid megaripples, with generally a NW-SE crest orientation, mostly occur around large sandwaves.

Aug 8, 2023 · Megaripples are current-generated seafloor bedforms of well-sorted sand or gravel and wavelengths over 1 m. In this aquatic eddy covariance study, we measured large rates of benthic primary production and respiration for a shallow-water sandy megaripple field exposed to strong tidally driven currents and intense sunlight.