MARSITECRUISE
Type | Oceanographic cruise |
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Ship | Pourquoi pas ? |
Ship owner | Ifremer |
Dates | 29/10/2014 - 16/11/2014 |
Chief scientist(s) | GELI Louis , RUFFINE Livio , HENRY Pierre , CAGATAY Namik |
GEO-OCEAN - UMR 6538 Univ. Brest, CNRS, Ifremer, Univ. Bretagne Sud Place Nicolas Copernic 29280 Plouzané |
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DOI | 10.17600/14000500 |
Objective | The cruise objective is to better understand the behaviour of the submerged section of the North Anatolian fault in the Marmara Sea. During the first leg (from 28/10 to 1/11), 10 acoustic geodesic stations were deployed on the seabed to directly measure the movement of the fault south of Istanbul: 4 stations for the IUEM European institute of marine studies UMR Ocean domains joint research unit; 6 Geomar stations. Inspection visits will be made every six months over 5 years, with Turkish seagoing facilities. During the second leg of the cruise (from 2/11 to 13/11), the ROV VICTOR-6000 was deployed to take samples (interstitial waters, gas, brines) and in situ measurements aiming to understand the processes of fluid migration along faults. 5 ROV dives (for a total of 148.4 hours) made it possible to acquire 18 gas samples, 28 RAMAN spectroscopy measurements and 41 measurements of gas current flow rates, using 35 interface core samplers and 2 core cutters for geomicrobiology, 7 titanium syringes to study rare gases. 12 Calypso long sediment cores were taken to analyze deep interstitial fluids, as well as 8 CTD casts for geochemical assessment of plumes detected by acoustics. Lastly, an acoustic bubble detector (BOB) and two ocean-bottom seismometers were accurately deployed by the ROV, to study the natural methane degassing phenomenon at the sea floor. The third leg (from 13 to 16 November) had a dual objective: i) acquire sediment cores in key sites for paleoseismicity studies aiming to specify the rate of recurrence of earthquakes; ii) recover Ifremer's and INGV's instruments which had been deployed during previous operations performed in the framework of the MARSITE programme. |