Description: Agadir Canyon is one of the largest submarine canyons in the World, supplying giant submarine sediment gravity flows to the Agadir Basin and the wider Moroccan Turbidite System. While the Moroccan Turbidite System is extremely well investigated, almost no data from the source region, i.e. the Agadir Canyon, are available. Understanding why some submarine landslides remain as coherent blocks of sediment throughout their passage downslope, while others mix and disintegrate almost immediately after initial failure, is a major scientific challenge, which was addressed in the Agadir Canyon source region during Cruise MSM32. We collected ~ 1500 km of seismic 2D-lines in combination with a dense net of hydroacoustic data. About 1000 km2 of sea floor were imaged during three deployments of TOBI (deep-towed sidescan sonar operated by the National Oceanography Centre Southampton). A total of 186 m of gravity cores and several giant box cores were recovered at more than 50 stations. CTD casts were collected at nine stations including one 13 hour Yo-yo CTD. The new data show that Agadir canyon is the source area of the world's largest submarine sediment flow, which occurred about 60,000 years ago. Up to 160 km3 of sediment was transported to the deep ocean in a single catastrophic event. For the first time, sediment flows of this scale have been tracked along their entire flow pathway. A major landslide area was identified south of Agadir Canyon. Landslide material enters Agadir canyon in about 2500 m water depth; the material is transported as debrite for at least another 200 km down the canyon. Initial data suggest that the last major slide from this source entered Agadir canyon at least 130,000 years ago. Living deep-water corals were recovered from a large mound field north of Agadir canyon. To our knowledge, these are the first living cold water corals recovered off the coast of Morocco (except for the Gulf of Cadiz). They represent an important link between the known cold-water coral provinces off Mauritania and in the Gulf of Cádiz.

Description: The cruise AL527 took place in the Western Baltic Sea in the period 6. – 14.09.2019. The cruise was carried out as a marine geophysical field course of Kiel University, supported by BONUS ECOMAP project. Starting and ending point of the cruise was Kiel. One stopover in Kiel took place during the cruise due to an exchange of parts of the scientific party (10.09.2019). The main aim of the cruise was to introduce marine geophysical acquisition to the students including hands-on experience in collecting marine geophysical data. This approach also included a first processing and interpretation of the data as well as the presentation of the first results. Two areas in the Western Baltic Sea were the main working areas of AL527. The first survey area was at Boknis Eck, a part of the Eckernförde Bay. The main objective in this area was to search for an underwater observatory from the Coastal Observing System for Northern and Arctic Seas Project (COSYNA), which was operated by GEOMAR and disappeared end of August 2019. For this purpose, a survey with a bathymetric multibeam system from the ”Marine Geophysics and Hydroacoustics” working group (Kiel University) was carried out. Furthermore, an underwater camera system was used for visual inspections. The second survey area was in the Mecklenburger Bay. The main objective was a pre-investigation of a buried beach for an upcoming cruise within the EU-funded project ACT-SENSE. Therefore, 2D reflections seismic, sediment echo sounder, and multibeam data were acquired. Additionally, 7 gravity cores were taken for ground trothing and sampling of the buried beach. In order to analyze major tectonic structures in the Fehmarn Belt and the Mecklenburger Bay, 12 additional seismic profiles were collected when transiting between the survey areas. Our investigations showed that a buried beach is located in the Mecklenburger Bay beneath a layer of mud. The sand deposits have an estimated variable thickness between 1m and 9m in the survey area. The top of the beach was successfully sampled with several gravity cores. Further investigations of these cores, together with the geophysical data, will be take place in the frame of the ACT-SENSE project. In the acquired bathymetric dataset from Boknis Eck some conspicuous zones could be identified, where possibly remaining parts of the missing underwater observatory are located. Unfortunately, it was not possible to validate these zones by the used underwater camera. These zones should be investigated by divers in the near future, for a reliable validation.

Description: The cruise AL542 took place in the Western Baltic Sea in the period 14. – 21.08.2020. The cruise was carried out as a marine geophysical field course of Kiel University. Starting and ending point of the cruise was Kiel. One stopover in Kiel took place during the cruise due to an exchange of parts of the scientific party (18.08.2020). The main aim of the cruise was to introduce marine geophysical acquisition to the students including hands-on experience in collecting marine geophysical data. This approach also included a first processing and interpretation of the data as well as the presentation of the first results. The main survey area of the first leg of the cruise AL 542 was the Bay of Mecklenburg. In the eastern part of the bay seismic and acoustic data were collected with the aim to identify historical coastlines and buried glacial structures. Further, the central part of the bay was mapped with the multibeam echosounder to find the Blinkerhügel, a small mound with reported accumulation of manganese nodules, investigated in 2002 by Hlawatsch et al. The Blinkerhügel was clearly identified as an outcropping ground moraine. Seafloor samples at eight locations were collected with a grab from the area of the Blinkerhügel. At one location stones with manganese crusts were successfully retrieved. The four survey areas of the second leg of the cruise were Mittelgrund, Noer and Damp which are located in the Eckernförde Bay and an area near Fehmarn which is located in the northwest of the island in the Fehmarn Sund. In the region Mittelgrund in the Eckernförde Bay a wellknown, developing pockmark field was surveyed with hydroacoustic and seismic methods. Furthermore, a known pockmark near Noer was surveyed with hydroacoustic methods. From the third survey area Damp Laminaria agitate algae have been reported. The aim in this area was to check, if it is possible to detect the algae with the hydroacoustic systems. Additionally, some video transects and seafloor samples were gathered for ground truthing in this region. In the survey area near Fehmarn a dynamic dune field was surveyed with hydroacoustic methods. This dune field is surveyed every year to document changes in the submarine environment.

Description: Summary The continental margins of southern Italy are located along converging plate boundaries, which are affected by intense seismicity and volcanic activity. Most of the coastal areas experienced severe earthquakes, landslides, and tsunamis in historical and/or modern times. The most prominent example is the Messina earthquake of Dec. 28, 1908 (Ms=7.3; 80,000 casualties), which was characterized by the worst tsunami Italy experienced in the historical time (~2000 casualties). It is, however, still unclear, whether this tsunami was triggered by a sudden vertical movement along a major fault during the earthquake or as a result of a giant marine slide initiated by the earthquake. The recurrence rates of major landslides and therefore the risk associated with landslides is also unknown. Based on detailed bathymetric data sets collected by Italian colleagues in the frame of the MaGIC Project (Marine Geohazards along the Italian Coast), we collected seismic data (2D and 3D) and gravity cores in three working areas (The Messina Straits, off Eastern Sicily, the Gioia Basin). A dense grid of new 2D-seismic data in the Messina Straits will allow to map fault patterns in great detail. One interesting outcome in this context is the identification of a set of normal faults striking in an EW-direction, which is almost perpendicular to the previously postulated faults. This EW-striking faults seem to be active. The area off eastern Sicily is characterized by numerous landslides and a complex deformation pattern. A 3D-seismic data set has been collected during the cruise using the so called P-cable in order to investigate these deformation patterns in detail. The new data will be the basis for a risk assessment in the working areas.