ALBERT

Description: Multibeam echosounder (MBES) data recorded during RV POSEIDON cruise POS498 between 18.04.2016 and 01.05.2016 off the south coast of Turkey in the Anaximander Mountains. The cruise aimed to recover observatories with the help of the Remotely Operated Vehicle (ROV) MARUM‐SQUID 2000, while the second main objective of the cruise was to recover sediments to study the thermal structure as well as the temporal evolution of the mud volcanoes. CI Citation: Paul Wintersteller (seafloor-imaging@marum.de) as responsible party for bathymetry raw data ingest and approval. Description of the data source: During the RV POSEIDON cruise POS498 the ELAC SB3050 multibeam echo sounder with a nominal sounding frequency of 50 kHz was utilized. 384 beams with a 1.5°(TX)/2°(RX) footprint are formed for each ping while the seafloor is detected using amplitude and phase information for each beam sounding. For further information consult http://www.mdsys.co.kr/down/ELAC/SB_3050.pdf. During POS498 the swath angle was set mostly between 90 and 70° with a survey speed of 6 knots. The ELAC SB3050 worked reliable in spite of working at the lower end of its depth range. Problems during the acquisition only occurred during bad weather conditions and a malfunction of the integrated navigation system (F180 unit) by which the heading of the ship in the data diverged from the true heading, which resulted in misplaced beams. Responsible person for hydroacoustic during this cruise / PI: David Voelker (dvoelker@marum.de). Chief Scientist: H. Sahling (hsahling@marum.de) CR: http://oceanrep.geomar.de/33307/ CSR: http://www.bsh.de/aktdat/dod/fahrtergebnis/2016/20160082.htm A special thanks goes to the watch keeper during POS498: Markus Loher