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Teachers
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Expedition 301
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Journal
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22 July 2004
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CORE ON DECK!!!
There are a lot of very happy (and very relieved) scientists on the ship today. Our first core arrived at 0530 this morning. Core has been coming every 4-6 hours since then. The science labs are bustling. I have been running around trying to get to each lab in order to find out what happens to the core once it is brought onto the ship. There is a lot of territory to cover; there are 7 floors of state-of-the-art laboratories and other scientific facilities on the JOIDES Resolution. For IODP Expedition 301, the labs are staffed by 48 scientists and technical staff. If you would like to take a virtual tour of the lab stack, check out this Web site: http://iodp.tamu.edu/publicinfo/tour1/index.html
Here is a partial update for today given by Adam Klaus, Expedition Project Manager/IODP-USIO Staff Scientist (USA):
We have now cored 15.4 m of basement (351.2 to 366.6 mbsf) and recovered 7.3 m. This is 47% recovery, which is quite good. In my previous email, I mentioned that Core 1301B-1R was drilled 5.9 m to get the space out on the rig floor correct. Well, the next core (Core 1301B-2R) took very long to cut just a short 4 m interval (it arrived on deck almost 7 hours after Core 1301B-1R). Since it took so long to cut, the drillers were concerned that there may be a problem with the bit, or that the core might have jammed in the bit preventing faster penetration, so they pulled the core after only 4 m of advance. So the next core had to be yet another short one (5.5 m) to ensure that we could get the space out on the rig floor correct again (4 + 5.5 = 9.5m ---- same length as a single joint of drill pipe).
While cutting the first 3 cores (Cores 1301B-1R to -3R), we used ~9 hours of actual rotating (or cutting time) with the drill bit. I mention this because each bit has a limited number of rotating hours before it starts to wear out. As we want to core this hole deeply into basement, Mike will be conservative and likely change the bit after ~50 rotating hours. Bits can last many more hours, but you certainly don't want them to fail. One thing that can happen is one of the rotating cones on the bit can fall off. The drillers can usually see when the bit is starting to fail because when one of the RCB bit cones starts to become loose, it begins to wobble - this causes erratic torque when rotating the drill string. These are designed to be very hard, so it's not a good thing to drop in the bottom of the hole!
DRILLER's SPEAK: "Rotating Hours" = the amount of time a drill bit spends grinding away at rock!
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 CORE BARREL. The drill string is the vertical pipe with the knobbies on it (I have shown this before). However, if you look closely to the right, you can see the core barrel hanging from a chain. The core barrel is approximately 10 meters long. Inside, it has a plastic liner called the core liner. At the bottom end (just out of the picture), there is a core catcher (a short connecting tube with “teeth” that let the core into the barrel, but not out). This picture was taken just before the drillers disconnected the drill pipe and placed the core barrel inside. Once the core barrel is placed in the pipe, it is allowed to free-fall to the bottom of the hole (over 2,500 m!), where it lands in the drill pipe just above the Rotary Core Barrel (RCB) bit. The core barrel will remain in this position until the hole is drilled 9.5 meters (or less if any problems come up). During drilling, the core enters through the bit and into the plastic liner in the core barrel. After the 9.5 m are drilled, the core barrel will be brought up to remove the core.
It is a beautiful day to get our first core. The skies are clear, but it is windy and the waves and white caps have picked up.
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 CORE ON DECK. This photo shows our second core of the morning. The core barrel has been removed from the drill string and the rig floor crew is removing the core liner. The pipe extending to the right is the core barrel. The whitish tube to the left is the core liner that is being pulled out of the core barrel. If you look closely, you can see the basaltic rock inside the core liner.
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 CATWALK. As soon as the core liner is removed from the core barrel, it is brought to the catwalk to be prepared for sampling. You can see how eager the scientists are to get to the core. These people have been waiting nearly 4 weeks for this event.
Carrying the core are Dennis Graham, Marine Laboratory Specialist (USA); Takamitsu Sugihara, Marine Laboratory Specialist (Japan); and Paula Weiss, Marine Laboratory Specialist and Curator (USA).
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 ANTICIPATION. Once the core is placed on the catwalk, it has to be prepared by the marine laboratory specialists. There are several steps that must be undertaken before the scientists are allowed to handle the samples. On IOPD Expedition 301, there are a number of anaerobic microbiology experiments that are being performed, which require collecting samples as soon as possible so that they can be sealed into containers that are flushed with nitrogen to remove the oxygen that is toxic to the microorganisms that the scientists plan to culture. If you look closely, you can see Fumio Inagaki, Microbiologist (Japan), in the red and white hat, selecting a sample from the core as the rest of the science party look on.
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 PREPARING SAMPLES. Once the microbiologists’ samples are collected, they are brought into the labstack core lab next to the catwalk. Almost immediately, they are placed into sterilized glass jars that are flushed with nitrogen gas to remove any oxygen that could be toxic to the anaerobic microorganisms in the core samples.
Satoshi Nakagawa, Microbiologist (Japan), is flushing a sample with nitrogen gas as Bjoern Steinsbu, Microbiologist (Norway), and Mark Nielson, Physical Properties Specialist (USA), watch the procedure.
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 GLOVE BOX SAMPLE PREPARATION. Some core samples were carried down one floor to the microbiology lab where they were placed into the glove box to be prepared. As soon as the samples were placed into the box, it was flushed with nitrogen gas to protect any anaerobic microorganisms from toxic oxygen. Microbiology is not always a delicate science; Verena Heuer, Organic Geochemist (Germany), has to use a hammer and chisel to break the hard basalt to collect samples for culturing the microorganisms that are thought to live inside the rock. (The hammer and chisel are sterilized to kill any bacteria on them before being put in the glove box.) Mark Nielson, Physical Properties Specialist (USA), and Tetsuro Urabe, Co-Chief Scientist (Japan), assist Verena with the procedure.
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 MICROBIOLOGY NOT ALWAYS A DELICATE SCIENCE. Mark Lever, Microbiologist (USA), is getting a workout as he collects a sample from a piece of basalt while Satoshi Nakagawa, Microbiologist (Japan), looks on.
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 SAMPLE STRATEGY. Once the microbiologists took the samples that they required for immediate preservation, the core was processed and taken into the core lab. Here the scientists have the challenging task of developing a sampling strategy that will get the most information out of the samples.
Here, Masumi Sakaguchi, Igneous and Metamorphic Petrologist (Japan); Rosalind (Roz) Coggon, Igneous and Metamorphic Petrologist (UK); Marion Dumont, Organic Geochemist (Sweden); and Will Sager, Paleomagnetist (USA), discuss their strategy. Joe (Bubba) Attryde, Core Technician (USA), is in the background.
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 FIRST CORE. Here it is - the first core of the leg. This is altered basement basalt from the top of the oceanic crust. The Styrofoam sections mark where the microbiologists collected their samples. When the microbiologists are done with the samples, any leftover materials will be returned to these sections.
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 GOING FOR MORE CORE. This view from the driller’s shack shows lines marking off the meters on the drilling pipe. The drillers use these as a rough visual guide to determine the amount of core they have drilled for this core barrel. The drillers do have a more sophisticated and digital method of telling the actual depth that has been advanced. They hope to be looking at this view for the next 12 days of scheduled coring.
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