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Teachers
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Expedition 301
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Journal
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28 July 2004
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“BUG DISCOVERY” and LAB SHOTS
Today, one of the microbiologists was brimming with excitement; he has found the first microorganisms of IODP. They were cultured out of a sample taken from Hole 1301B. The scientists will continue to study them to see if the microorganisms came from subseafloor environment, or if they were introduced by drilling contamination. In addition, I made it around to the chemistry and microbiology labs to check out what they were doing.
Here is a partial update for today given by Adam Klaus, Expedition Project Manager/IODP-USIO Staff Scientist (USA):
Coring continues to progress with slow but steady penetration and hole conditions good.
Core 1301B-24R to -25R were from 505.9 to 515.5 mbsf (240.74 to 250.34 m below the top of basement!) and recovered 3.4 m (35%). It took almost 12 hours to cut and retrieve these two cores.
As of this afternoon, we will have been coring 7 days (including pipe trip into hole). This second bit is nearing ~40 hrs of rotating time and I believe sometime later today, we will start considering when we should pull it out and start with a new bit. This is a bit of a decision point... for the next bit run do we run a longer bottom-hole assembly or not?
The bottom-hole assembly (BHA) consists basically of the drill bit, drill collars, and tapered drill collar (there are a few "subs" in there as well). The drill collars are the very heavy, thick-walled pipe that keep the drill string in tension and are responsible for putting the weight on the bit when we slack off on the drill string. One very good thing about the drill collars is that they are a uniform thickness and the outside of the pipe is smooth along the entire length. This is very good for drilling as the flow of cuttings out of the hole along the drill collars is not disturbed by any "upsets" (changes in pipe diameter) as it is with the drill pipe. Another critical point in the drill string is where the drill collars pass upward to the drill pipe. The drillers’ experience is that hole problems substantially increase once this change in diameter gets into the open hole. What happens is cuttings and rubble that settle out and land on the top of the drill collars where this change in diameter occurs. This often leads to increased torque, increased pump pressures, and often to stuck (sometimes permanently) pipe. If this were to happen in the extreme, we would have to sever the BHA to retrieve the drill string and we'd leave a whole lot of drill collars in the hole - not good for a CORK installation.
So... on this second bit run, Mike added some more drill collars so that the change in diameter at the top of the drill collars would not pass into open hole below the 10 3/4-inch casing. On the next bit run, the big question is do we run in with an even longer BHA with more drill collars or a much shorter one? The shorter one would have more of a chance to get stuck, but if it did, we'd still have some open hole if we had to sever it. Most everyone feels that running a longer BHA is the way to go.
Another potentially related question is how much farther to penetrate. If we want to limit penetration so that only the slick-walled drill collars are in the open hole, there is a limit to how deep we could penetrate. (Mike is calculating this now; we only have so many on board and if we were to lose the entire BHA, we have to ensure we have enough for the rest of this cruise as well as not negatively impact future cruises).
The other thing to balance is the risk-benefit of how far to penetrate. The benefit being the expansion of science of each incremental increase in penetration versus the risk of losing the hole which only increases with time and depth in hole. There are no easy answers and the co-chiefs are trying to pick the best way forward and have already discussed this with a number of scientists. As always if you have any strong feelings on this issue, please let us know.
Countdown to Astoria: 23 days
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 The coring continues. Thanks to Bill Crawford, Image Specialist (USA), for this excellent view of the derrick.
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 THE FIRST “BUGS.” Bert Engelen, Microbiologist (Germany), is very excited as he shows off the first microorganisms found in the IODP program. (This is the first expedition of the newly formed IODP). Check out the next image for a close-up view. The next question Bert has to answer is whether or not these microorganisms he cultured were growing in the rock sample collected from Hole 1301B, or if they were introduced by contamination during the drilling process. Still, he is VERY EXCITED!
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 These close-up shots show the first microorganisms cultured on IODP Expedition 301. The blue dots represent the microorganisms. They were photographed through a very powerful microscope; according to the scale, the individual bacteria cells are approximately 0.5 microns in diameter. Bert Engelen, Microbiologist (Germany), who cultured these microorganisms, still has to determine if they were growing in situ (at the pressure and temperature conditions of the rocks below the seafloor) or if they were introduced during the drilling process.
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 The other microbiologists are working hard to find more examples of microorganisms from Hole 1301B samples. From left to right are Shusako Goto, Physical Properties Specialist (Japan) (back facing the camera); Fumio Inagaki, Microbiologist (Japan); and Satoshi Nakagawa, Microbiologist (Japan).
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 Paula Weiss, Marine Laboratory Specialist (USA), is cutting a core sample on a rock saw. After the initial microbiology samples are taken, the petrologists mark each of the pieces in a core so that they can be split. One half goes into the archive half to be preserved in a storage facility. The other half will go into the core room to be sampled by the shipboard scientists. After it is sampled, it will also be preserved in a storage facility.
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 Dennis Graham, Marine Laboratory Specialist (USA), is in the chemistry lab preparing the Inductively Coupled Plasma–Emission Spectrometry (ICP-ES) unit to measure a variety of major and trace elements that make up the basalt samples recovered from Hole 1301B.
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 Before the ICP-ES unit can be used, the glass components must be very, very clean - so they are cleaned in an acid bath. Dennis Graham, Marine Laboratory Specialist (USA), is cleaning the glassware under a fume hood in the Chemistry Laboratory.
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 Ahhhh… The end of another day and I am writing another entry in my journal to share with all of you folks at home. Shown are Geoff Wheat, CORK Geochemist (USA), who is working very hard on several articles for journals, and, me, Jonathan Rice, Teacher at Sea (USA).
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