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Cruise diarySunday 20th July 2003 |
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Dave writes..."Last night I weaned myself off the travel sickness tablets in an effort to see how I would cope with the rigours of life at sea without the assistance of drugs. I can safely say that I think I have found my sea legs as I didnt feel too rough. Bizarrely, on the early watch Geraint caught a flying fish after it made a suicidal leap onto the ships starboard side. It was only a tiddler so he threw it back. Today has been fairly uneventful. This is because we are sailing directly toward the Carlsberg Ridge which is a mid ocean ridge lying just off Somalia and Yemen. Bram held a talk for the crew to let them know about the geology and why we are doing what they are doing. As such we have not made any experiments. We should arrive at Waypoint 4 on Tuesday morning where we will start dredging the ridge axis. Late that night we crossed over the equator."
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Tina writes..."At 03:00, GMT Geraint (head of the UKORS department at SOC) caught a flying fish. Or rather, the flying fish threw itself at him while he was on deck having a cup of coffee! Sadly, he threw it back before I could get out fast enough to take a photo. Its quite quiet at the moment because all we are doing is steaming towards the next waypoint. The most interesting thing is that our watch leader, Rex, is eating more and more bacon at each breakfast. The chef is worried we might run out before we get back to Mahe Island. At 13:30 local time, Bram held a presentation for the crew, about what the cruise is studying and why we are here. I went too, because as a chemist, I am always looking to increase my geological knowledge. Bram explained we are exploring the Carlsberg Ridge, a 4000m trench in the middle of the Indian Ocean, which is spreading apart at about 2cm a year. There are underwater volcanoes here, and we are hoping to find evidence of activity in the rock samples we are going to take. We plan to do 30-40 dredges in all. One reason we are here is that the magma that gives rise to the new ocean floor here may be diverted from a mantle plume that is spreading outward from East Africa, hundreds of miles away. This magma would look distinctive geochemically, and would be different from a direct source of magma immediately under the ridge. Mantle plume magma is at about 1500ºC, compared with mid-ocean ridge magma of 1200ºC.
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