Profile of sediment echo sounding with links to ParaSound data files and swath sonar multibeam bathymetry during METEOR cruise M70/2b

Two highly active mud volcanoes located in 990-1,265 m water depths were mapped on the northern Egyptian continental slope during the BIONIL expedition of R/V Meteor in October 2006. High-resolution swath bathymetry and backscatter imagery were acquired with an autonomous underwater vehicle (AUV)-mounted multibeam echosounder, operating at a frequency of 200 kHz. Data allowed for the construction of ~1 m pixel bathymetry and backscatter maps. The newly produced maps provide details of the seabed morphology and texture, and insights into the formation of the two mud volcanoes. They also contain key indicators on the distribution of seepage and its tectonic control. The acquisition of high-resolution seafloor bathymetry and acoustic imagery maps with an AUV-mounted multibeam echosounder fills the gap in spatial scale between conventional multibeam data collected from a surface vessel and in situ video observations made from a manned submersible or a remotely operating vehicle.

Multibeam bathymetry of Timmiarmiut and Skjoldungen-Fjord, Southeast-Greenland

During an expedition with the topsail-schooner ACTIV in July 2014, parts of the Timmiarmiut-Fjord and nearly the entire Skjoldungen-Fjord in Southeast-Greenland have been mapped using a temporarily installed Seabeam-1050 multibeam echosounder. In addition, at 11 positions in the fjords, depth profiles of temperature, conductivity, salinity and sound velocity have been measured with a CTD.

Gridded bathymetry from multibeam echosounder HS-DS2 data of the cruise M51/4 (2001)

Bathymetry based on data recorded during M51-4 between 13.12.2001 and 28.12.2001 in the Black Sea. The purpose of the present-study was to sample sediments and the water columns of the nw/sw Black Sea and the E Marmara Sea to study a) a high resolution sediment records of Holocene climate, b) biogeochemical associated with deep anaerobic methane oxidation, and c) element cycling in the stratified water column. Bathymetric data (hydrosweep + parasound) was primarily used to choose appropriate sites for coring of undisturbed sediments. Samples were taken for future analyses of abundance and activity of bacteria, geochemistry and dating.

Gridded bathymetry from multibeam echosounder ELAC BottomChart MkII data of the cruise POS317/4 (2004)

Bathymetry based on data recorded during POS317-4 between 16.10.2004 and 04.11.2004. This cruise focused on methane seeps off Georgia and Turkey. Different geological settings were studied by using pressurized sampling techniques and remotely operated vehicles (ROVs).

Multibeam and seismic survey, physical oceanography, and sea-bottom videos from the Bay of Biscay

We report the northernmost and deepest known occurrence of deep-water pycnodontine oysters, based on two surveys along the French Atlantic continental margin to the La Chapelle continental slope (2006) and the Guilvinec Canyon (2008). The combined use of multibeam bathymetry, seismic profiling, CTD casts and a remotely operated vehicle (ROV) made it possible to describe the physical habitat and to assess the oceanographic control for the recently described species Neopycnodonte zibrowii. These oysters have been observed in vivo in depths from 540 to 846 m, colonizing overhanging banks or escarpments protruding from steep canyon flanks. Especially in the Bay of Biscay, such physical habitats may only be observed within canyons, where they are created by both long-term turbiditic and contouritic processes. Frequent observations of sand ripples on the seabed indicate the presence of a steady, but enhanced bottom current of about 40 cm/s. The occurrence of oysters also coincides with the interface between the Eastern North Atlantic Water and the Mediterranean Outflow Water. A combination of this water mass mixing, internal tide generation and a strong primary surface productivity may generate an enhanced nutrient flux, which is funnelled through the canyon. When the ideal environmental conditions are met, up to 100 individuals per m² may be observed. These deep-water oysters require a vertical habitat, which is often incompatible with the requirements of other sessile organisms, and are only sparsely distributed along the continental margins. The discovery of these giant oyster banks illustrates the rich biodiversity of deep-sea canyons and their underestimation as true ecosystem hotspots.