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Cruise diary
Saturday 26th July 2003
Dave writes...
"Well, the weather held off long enough for us to bring up one more dredge. So you have been spared the lecture on the monsoon… for now anyway. The dredge was sent into a canyon formed by a transform fault system (oblique to the spreading direction), in the hope of finding any evidence of volcanic activity which might indicate ridge spreading. If there is any volcanic material it would provide evidence that there is a shear stress that is pulling the plates apart and oblique to one another. If we had it would have been one of the first successful hits on this sort of landform (very exciting). We didn’t get any volcanics, the canyon was just full of muddy sediment.
Both Tina and I slept over by 5 and 10 mins respectively, on the plus side it takes less than 2mins to be up and on station. I was woken by my alarm 20mins early but turned it off as I was on sleep auto pilot. I don’t know what Tina’s excuse was, I think she’s just lazy (hehehe, I wonder what kind of rebuke I will receive).
I have received a question from our base in Southampton - it reads:
"How many dredges do you have on board and have you ever lost any?"
The answer is six, we have not lost any yet, however it does happen quite frequently hence why we have six on board. The dredges have two safety pins one which has a yield strength 3.25 tonnes and the other 5 tonnes. The 5 tonne pin is actually a 7 tonne pin that has been cored so as to weaken it sufficiently, so I’m told. They break when the dredge hits a rock outcrop and gets stuck, in order to prevent the ship being dragged back. We have a gauge in the science lab that lets us know how much stress the dredge is under so we know; a, when the dredge gets a nibble on the rocks and b, if the pins are nearing failure. I suppose it is quite cool to be uncovering new rocks, etc that no one has ever seen before, but the feeling soon wears off. However I’m looking forward to getting the results back from the geochemistry because that is when you uncover the real mysteries, but you also create some mysteries.
Bram has reported to me that at night time you can see bioluminescent algae in the sea, which look like little white dots and that if you look hard enough it looks like warp-speed from star trek. He has had sleep deprivation and had been drinking at the time, it could explain a lot. I will however let you draw your own conclusions. I will report back if I can see them.
Oh how I laughed today when I saw Sophie after she had been sunbathing peacefully at the bow, when all of a sudden a huge wave crashed over the side and soaked her top to bottom, she did not look amused. I on the other hand did..."
Tina writes...
"Well, I did turn up in my pink pjs for my shift (5 minutes late). Dave was about 15 minutes late, and took some time to wake with the phone. They were dredging overnight, so the ship was quite steady and I slept very nicely. This morning’s dredge came up on our shift, and had a bucket of mud attached (no rocks). So we know there isn’t any fresh rock to be sampled (Rex and Bram had a theory that there was a micro-rift spreading across a valley floor that we might be able to find). Sophie also sent down a net to sample any possible organisms (this would likely have been shrimp larva if there was a hydrothermal vent nearby). The good news is that the net came back, but sadly came back empty. This was because the frame broke, fortunately Rhys is going to make a new frame that won’t collapse and Bob is doing the needlework.
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Sophie: Netmaster |
Me: a short walk before another full english breakfast
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There were a couple of nice big waves that washed over the stern as we were on deck, making sure we were all soaked (even though this time Rex had waterproof trousers on). Dave was first to fill his boots, as a wave seemed actually directed at him personally. Then we all got the big two waves, complete with spray. You can tell when the sea seems to be building up to something, when the ship starts lifting higher and higher and then goes back down. The stern of the deck is non-slip, so we just brace ourselves until the ship steadies and then get back to what we were doing.
Geraint foolishly comes to the main lab with his first coffee of the day. The last two days this has been perfect timing to help me change the ping echo sounder back to read the bottom of the sea floor (changing from reading the ping that we attach to the cable 150m above the dredge, to read where the dredge is). There are a few adjustments to be made on the echo sounder, but the EA500 manual is a complex book for a novice, so it’s been very useful having someone patient to show us how it’s done, even if it’s at 7am and before his first cup of coffee. From what the ping technical person Jeff says, it’s a black art that balances sensitivity against interference.
After the dredge, I went up to the bridge and had a look at our heading with Phil. The bridge is fascinating, there are lots of charts and read-outs and radar to look at, and of course the look-out over the bow. There seems to be a time-warp up in the bridge, it’s easy to lose half an hour. I missed the post-dredge cup of tea but Dave mercifully made me one when I got back.
Phil (who is on our 4-8 shift watch) charts where we next want to go, and we set off after the dredge is up and safely stowed. As we moved off to the next waypoint, we changed course so that the swell is now hitting across our beam. There is a steady 30 knot wind, and things are definitely more roller-coaster than yesterday. Even though things are all tied down, every so often an object surprises you by moving across the floor or desk by itself.
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Rex has good sealegs |
The Master (Keith Avery) visits CapComm mission control |
Andy has felt a little unwell again, but seemed to recover quickly. I feel OK so far, just a bit groggy from lack of sleep. Rex had a bowl of Japanese pot noodle at 5am and then Dave and me wanted one too, so we must be feeling OK. Two hours later I also managed breakfast, and I’m just waiting for my mail until I go back to bed. We are due at the next site about 9:30am local time, and we will see if the sea is too rough for a dredge or not (we can’t really tell until we stop).
Saturday pm: Another dredgeful day, with Sophie & Carla’s watch (and Andy, and Rex who were also awake and up) bringing a lovely haul of pillow and sheet lava rock, (glassy layers), glass chips, and an interesting subset of thinner layer sheet lava rock with rope-like flow structure. Also there were rocks with manganese crusts.
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Bleached rocks: good evidence for hydrothermal leaching |
Andy Milton: not ill and not camera-shy |
Today is curry night in the galley (but of course, with the new nocturnal bodyclock I’m not hungry). It smells very good though…"