BobGeo 2009. Day 3 – early results

Another fine morning with clear skies. However, with the Pourquoi pas? sailing at around 8 knots the wind felt quite strong and was very bracing as I stood on the front deck of level seven looking for the dolphins.

They did appear but because of the strong wind and the sun shining on the LCD display of the video camera I only managed to get one or two short clips. In the early morning, before I was up the corer, box sediment grab and scampi were recovered. The core was not as long as had been hoped for, the sediment grab did collect some sandy sediment and Scampi returned with images.

The first samples came back this morning, sediment and images so, it was straight down to the Level 3 deck to see what there was. Unfortunately the first deployment of the big corer (Carottier) only manage to go down 1 or 2 metres before hitting rock and had to be brought back up.

Nereis - Ragworm

The box sediment grab contained around 20 kilos or so of sandy sediment. People were soon showing me the small bits of coral and the little crab that was running around. There was also some small worms to be seen which to me looked very similar to a nereis (ragworm).

Alexis Khripounoff, Sophie Arnaud and Brigitte Guillaumont (below) were there taking sample cores to examine the sediment more closely in order to see what kind of fauna they could find.

As far as I know nothing too exciting was found but they did find bits and pieces of coral. Maybe the next time will provide something more substantial.

The SCAMPI was also in operation and brought back some digital images of the seafloor. There was not to much to see apart from one or two small fish, small starfishes and the occasional small bits of coral. I have been promised that there will better to come, so watch this space.

Most of my afternoon was spent in the ‘Scientific lab’ trying to learn the differences between Chirp, Seismic profiling. Both use sound which is directed towards the sea floor and it bounces back like an echo off each of the interfaces that it meets on the way down through the sediment. They work using different frequencies of sound and the one people call the Sismique (seismic) uses a much lower frequency than the Chirp and can travel through rock, whereas the Chirp bounces back of the rock. A simple way to understand the different frequencies is to think about standing outside a building where a rock band is playing . From outside all you can really hear are the sounds of a bass guitar (low frequency sound) and maybe a bass drum which travel through the walls (Seismic). It is not until you enter the dance hall that you can then start to hear the other guitars and the singer who are all making sounds at a higher frequency, (Chirp) with their sounds not being able to penetrate the walls and bouncing back into the room

Today was also very frustrating as I tried to edit some of the video clips. The software that came with the camera as far as I could see is only able to trim the clips and not join them together. I did manage to download some other video editors which was very time consuming and even more annoying when they did not work either. So it seems that for the time being I will not be able to post any clips on our YouTube account. Therefore in the meantime here are some photographs from the last couple of days.

Sunrise over the Bay of Biscay

Looking out to sea over the bow of the Pourquoi pas?

Looking up to the Bridge from the level 3 rear deck

The stern showing the large A frame which is capable of lifting 55 tonnes and is used for launching a submersible and also some of the smaller bits of equipment.

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