Deutsches Ozeanographisches
Datenzentrum Inventur der Heincke-Reise HE413 (DOD-Ref-No.20140147)
Inventory of Heincke Cruise HE413 (DOD-Ref-No.20140147)

Plattform
Platform
Reise-Nr.
Cruise-No.
Zeitraum
Period
Projekt
Project
Arbeitsgebiet
Working area
Heincke HE413 13.01.2014 - 19.01.2014   North Sea  

Fahrtleiter
Chief Scientist
Institut
Institute
Auslaufhafen
Port of departure
Einlaufhafen
Port of return
Stationskarte
Station map
Schiffsroute
Trackchart
Romer Miriam Universitat Bremen, Zentrum fur Marine Umweltwissenschaften Bremerhaven Bremerhaven   

Ziel der Reise / Objectives of Cruise:

The cruise aimed to map the distribution of gas emissions to the water column and investigate seepage related processes in the study area. Since the study area is located in shallow water <50 m, gas bubble emissions to the water column are also a potential source to atmospheric methane concentrations. We planned to employ a wide array of ship- and AUV-borne acoustic and optical methods to map the seafloor, seepage related features, and bubble emissions. A novel AUV for automatic bubble detection and sampling should be tested and calibrated during the cruise. This tool will allow for efficient, unsupervised seepage detection and sampling within large areas in future. The cruise should contribute to a better understanding of seepage distributions and processes in the study area in the southern North Sea. The cruise started in Bremerhaven on Monday, 13 of January, and after a transit of ~20 hours to the working area in the Netherlands sector B13, the station work began Tuesday morning, 14 of January. In total, 35 stations were conducted during the five working days until Saturday, 18 of January. Seafloor, subbottom and water column mapping using ship-mounted hydroacoustic systems were performed during 14 surveys, which were mainly done during night times. The AUV was deployed three times, whereas with each dive a different sonar or video system (multibeam, sidescan sonar and imaging sonar) was mounted for testing. A transect of nine stations in E-W direction over the main gas seep area was sampled with CTD deployments. The water samples taken were analyzed for their composition of light hydrocarbons and microbial methane consumption. In addition, an underwater mass spectrometer (UWMS) was deployed twice at the main cluster of gas flares to analyze the methane concentration in different water depth over the entire seep area. After leaving the working area and a transit of more than 26 hours against the waves, we arrived in Bremerhaven on Sunday afternoon, 19 of January. The cruise was planned to last until Wednesday, 22 of January, but had to be cancelled earlier due to an upcoming storm prohibiting further deployments or useful mapping. However, during the five days in the working area several calm periods and waves of maximum 3.5 meters height allowed for the deployments of our large equipment and good hydroacoustic data during mapping. Therefore, the entire planned program could be realized within these five days. In summary, the cruise was very successful and many data of high quality was collected, which will be analyzed subsequently.

Messungen / Measurements

Institut
Institute
Wissenschaftler
Scientist
Anzahl
Number
Einheit
Unit
Typ der Messungen
Type of measurements
Kommentar
Comments
Daten im DOD
Data in DOD
MARUM Korber Jan-Hendrik 3 diving(s) G72
Geophysical measurements made at depth (below near surface and above seafloor)
AUV dives with different sonar systems mounted. no
MARUM Romer Miriam 14 survey G74
Multi-beam echosounding
. no
MARUM Mau Susan 14 deployment H10
CTD-Stations
. no
AWI Gentz Torben 2 deployment H33
Other dissolved gases
Measurements of dissolved methane concentrations in the water column using the underwater mass spectrometer towed from the vessel. no
9.11.2019