MoccoMeBo Climate-driven development of Moroccan cold-water coral mounds revealed by MeBo-drilling: Atlantic vs. Mediterranean settings - Cruise MSM36 - February 18 - March 17, 2014 - Malaga (Spain) - Las Palmas (Spain) (English)

Cold-water corals (CWC) are the engineers of one of the most important ecosystems of the bathyal zone. Sea floor structures largely constructed by these organisms, usually termed cold-water coral mounds and ridges, are widely distributed along the Moroccan Atlantic margin (MAM) as well as along the Moroccan Mediterranean margin (MMM). During expedition MSM36 with R/V MARIA S. MERIAN several of these CWC mounds with heights of 10-90 m have been drilled with the Bremen Sea Floor Drill Rig MeBo. With the eleven successful MeBo drillings yielding a total of 382 m sedimentary record (a) two mounds have been fully penetrated, (b) from six mounds very long records (up to 70 m) were retrieved, and (c) three off-mound drillings provided undisturbed paleoceanographic records to frame the paleo-environmental history driving CWC development. The material collected will contribute to address the major objective of this cruise to gain detailed insight into the initiation and development of the Moroccan coral mounds, which for periods older than ~30,000 yrs BP are largely unknown so far. Regarding the occurrence of CWC at both sites of the Strait of Gibraltar a kind of "seesaw" pattern has been observed for the last glacial-interglacial cycle. Whereas along the MAM CWC growth was most pronounced during the last glacial and terminated with the onset of the Holocene, along the MMM CWC only started to (re-)colonize the area at ~14,000 yrs BP. The newly obtained long records from both sites will test whether the observed Gibraltar seesaw pattern is a consistent feature that was also persistent further back in time. Such knowledge will contribute to a better assessment of the ultimate climatic link driving the forcing factors that control the occurrence and long-term development of CWC.