JC010: Mud volcanoes and submarine canyons


 JC10



Cruise diary


Day 4: Sunday 24 June 2007
Position: 39°34.3N 10°18.11.6W (Google Earth reference: 39 34’3”N 10 18’11”W)
Weather: Sunny with light cloud


Tina writes:

"One of my first questions when joining the ship was a somewhat panic-stricken “but how will I know when we stop?”.  It might sound a silly question, after all you can see when we are moving and when we are not, but this is a BIG ship and I’m not always looking out of a porthole or doing something up on deck and if there is one thing this ship is hot on, it's being where you should be at the correct time.  So when I was told to ‘go to the ROV room when the ship stops’ I was worried.

Being where you should be at the right time is crucial to the expedition, it can take hours to deploy (put in the right place) one piece of equipment and the ship can only deploy one thing at one time.  If you had two pieces of equipment out, trailing many kilometres of cable, you could get some really serious knots.

So at the start of a specific location a list of the items that should be deployed, in the correct order, is stuck on the notice board. Today the list read:

Megacore
Bathysnap
Megacore
ROV

1. Make PixelFly mosaic of sand dune at WP89
2. Collect one small box core from dune
3. Make PixelFly mosaic of xenophyophore at WP44
4. Collect 1 small and 2 large boxcores containing xenos
5. Find DOSOL Lander

 

Everyone else knew what it meant.  I spent most of today working it out! (I am writing a guide to what each one is which I will post shortly). 

Deploying the equipment tells you what is going down BUT not what experiment is on the equipment, and there might be two or three people’s experiments being carried out.  Usually you can figure it out quite quickly.  To have an experiment carried out on board can take YEARS of preparation so when a scientist has his or her experiment under water they keep a careful eye on what is going on.

As regards my concern about knowing when the ship stopped, I was told ‘you will just feel the difference’ - and you can! Somehow the whole motion of the ship changes.  I can be in the lab in the centre of the ship without a porthole in sight and the instant the ship stops you can feel it.  At that point you know it is action stations..." 


Richard writes:

"Today I was able to start working on my first cores. These had been taken at a depth of 3500m in the early morning and were back at the surface by lunchtime. I was really looking forward to working with the cores as I have read and heard so much about them since becoming involved in the whole Classroom@Sea project. 

When the cores first came on deck, the scientists took some measurements and lots and lots of pictures. Although it is strange to see some of the greatest minds of their generation taking photographs of what most people would call mud, their enthusiasm really does rub off on you and you become totally immersed in what is happening.

I first helped George to cut some cores so Kostas can perform some chemical analyses on them when they are returned to Liverpool University. Simply put, this will involve him checking the amounts, and nature, of carbon within the sample in order to understand more about carbon cycles within the deep sea.

Next I had a chat with Andy Gooday about some Xenophyophores (pronounced Zeenofyofores - one is pictured to lthe left) that he had extracted from the core samples. Andy told me that, although first described in 1884, this particular type of Xenophyophore had never been found as a whole organism until this cruise. It was extremely exciting to me, someone who had never heard of Xenophyophores before, to find this out, but as you can imagine Andy, who is somewhat of an authority on these creatures (in the past he has discovered new species of them!), was over the moon!

Why is Andy so interested in Xenophyophores? I decided to find out a little more… You may have already read about them in Virginia’s blog from 11 June, but here is a little more. Any organism that is made of just one cell (eg an amoeba) has to be pretty small to survive. This is because they work mostly by receiving and excreting substances by diffusion. If the cell is too big this can not happen quickly enough so the organism will either die because it does not get enough of something (eg oxygen) or cannot get rid of enough waste products and so is poisoned. Xenophyphores have a test (a shell like structure) surrounding them and inside they have very long branching strands of protoplasm to increase the surface area to volume ratio. The type Andy was concentrating on today was the species Aschemonella raumuliformis, which almost look like small tangles of bushes. Other types look like small (although when I say small, we are talking up to 15cm in diameter!) human brains, and have many folds and ridges. Andy thinks that these different shapes may help the different types of Xenophyphore to feed as they appear to be suspension feeders. One important thing Andy has to consider when working with these organisms is temperature. Can you work out what temperature he has to keep them at and why?

I also helped Teresa to process some cores. She is continuing with some unfinished work looking at the distribution of macrofauna (‘fauna’ means ‘animal life’ and ‘macro’ refers to the size. Why don’t you try to find out what size this is?). Before they are sieved, the samples are cut according to depth: 0-1cm, 1-3cm, 3-5cm, 5-10cm, 10-15cm and 15-25cm. The samples were then homogenised by, Suzie and I. Although this sounds incredibly difficult, it really means that we were stirring buckets of muddy water with our hands, getting them dirty at last! After they are homogenised, the samples are then sieved through two different sieves, one of 500µm (micrometer, 1000th of a millimetre) mesh and one of 300µm mesh. This traps the organisms Teresa will study.

Anyway, three hours after my shift has finished Teresa has had enough of me and sends me to bed. Happy to have got my hands dirty at last!

Richard getting his hands dirty

Intact specimens of the xenophyophore Aschemonella



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