Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Poseidon	POS442	31.10.2012 - 09.11.2012		Mediterranean Sea

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Petersen Sven	Helmholtz Centre for Ocean Research Kiel (GEOMAR)	Messina	Messina

Ziel der Reise / Objectives of Cruise:

During cruise P442 we investigated the local geological setting of a known hydrothermal deposit (Palinuro Volcanic Complex) in the Tyrrhenian Sea in high-resolution using the capabilities of the autonomous underwater vehicle (AUV) "ABYSS" from GEOMAR. October 31st 2012 RV Poseidon is leaving port at 18:00 and heading for the Palinuro volcanic complex. November 01st 2012 Arriving in the working area at 08:00 but wind and waves are too high to deploy the AUV. Since weather forecast sees improvement towards the evening, we wait. At 16:00 scientific work starts with the deployment and calibration of transponders (station 468) near the western summit of Palinuro volcanic complex, where known massive sulfide occurrences exist. November 02nd 2012 In the morning the AUV is launched for its first mission (station 469AUV), a multibeam survey using the Reson Seabat 7125 with a 200kHz setting and the magnetometer. The mission is flown at an altitude of 100m above bottom. The AUV is working fine during the entire day. November 03rd 2012 Mission ends shortly before 01:00 LT when the AUV surfaces. The instrument is later recovered in daylight for charging the batteries. The second dive is planned with two consecutive missions over the summit crater hosting the mineralization. The first part of the mission is a mutlibeam survey using the 400 kHz setting and flying closer to the bottom (40m altitude) followed by a sidescan sonar survey (210 kHz, range 400m) following the same track. The AUV is launched at 19:49 LT and the mission (station 470AUV) started shortly thereafter. Early in the mission a reset of the vehicle ends the station. Remainder of the day is used for identifying the problem. November 04th 2012 The next station (station 471) is a repetition of that from the previos day with the 400 kHz multibeam. The vehicle is launched at 10:14 LT and the mission started shortly thereafter. The vehicle performed well and was recovered at 15:39. The next dive (station 472AUV) was launched at 20:03 LT and repeated the sidescan sonar mission from the previous day. The mission lasted until the next morning. November 05th 2012 The AUV was recovered in the morning and reconfigured during the day for the next mission. Poseidon performed a multibeam survey (station 473) during the day of the shallowest part of the Palinuro volcanic complex. Increasing wind and swell in the afternoon and evening did not allow for deployment of the AUV. Waiting on weather until the next morning. November 06th 2012 The AUV was deployed in subbottom profiling configuration at 07:28 LT (station 474AUV). The trimming was incorrect at the beginning and the AUV had to be recovered. The relaunch started at 08:10 LT. Mission was slightly short to a vehicle reset. Vehicle was recovered 13:29. Subbottom data was collected but no magnetic data. The evening was spent with changing from the SBP configuration to the photo configuration. November 07th 2012 The next mission (station 475AUV) was deployed at 08:12 LT in order to take photographic images from various areas on the summit. The mission went fine, however, photos were only taken during the first part of the survey, while magnetic data was collected during the entire mission. After changing back to the multibeam configuration during the afternoon, the AUV was deployed a last time in the evening (19:50 LT, station 476AUV) collecting 400 kHz echosounding data adjacent to the previous dive areas. During the dive an oil leak was progressively becoming more severe, so that the dive had to be terminated after midnight. November 08th 2012 The AUV was left at the surface until it could be recovered at daybrake. Shortly thereafter the transponders were released (stations 477 and 478) and RV Poseidon started the journey back to Messina with a short top next to Stromboli. November 09th 2012 Poseidon reached the pilot station at 08:45 LT and docked in Messina at 09:11 LT.

Messungen / Measurements