A fruitful dive

Close up of Bathymodiolus azoricus mussels colonising the Eiffel Tower hydrothermal edifice. Photo Victor

This morning, a new twist in the cruise’s weather saga: the weather conditions will prevent us from recovering Victor. Gee, didn’t we already write that yesterday?

The OBT, ocean bottom tiltmeter), a new autonomous instrument, was deployed near SEAMON west. This primarily geophysical monitoring node is now supplemented with very precise measurements of seafloor tilt. Then Victor travelled toward the Eiffel Tower vent to finish installing SMOOVE (Smart Ocean Observatory Video Equipment), the new name of the camera on the ecological monitoring module TEMPO. The tests were reassuring.

Victor then moved on to the Montségur vent site 50 m south of the Eiffel Tower. There, the ROV set up the particle trap and an ADCP/CTD current meter. Several organisms (deep-sea mussels, shrimp, crab, polychaete worms, etc.) were sampled using a suction sampler. As the dive had been prolonged, the extra time was used to carry out a thorough video reconnaissance of the Eiffel Tower vent. This operation began in 2000 and is used to monitor the temporal changes on the edifice, in the active zones and in faunal distribution.

The decision to recover Victor was made at 1500, after a 44 hr dive!

The ocean bottom tiltmeter (in the back of the picture) was deployed very close to the SEAMON observatory node (in the foreground). Photo Victor

The particule trap on the Montségur hydrothermal site. Photo Victor

Smoker on the Eiffel Tower sulphide edifice. Photo Victor

Sampling with the faunal suction sampler. Photo Victor

Recovery of a lost temperature probe. Photo Victor