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Teachers
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Expedition 301
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Journal
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29 July 2004
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CATCH-UP DAY
Today was a good time for catching up on a variety of things around the ship while the rig floor crew tripped out to change the rotary core barrel (RCB) bit. The drilling with the second bit went very well, but the RCB bits are only used for 50-60 hours of drilling time before they are replaced. If the bit was used much longer, we would run the risk of if failing and dropping pieces into the hole. If this were to happen, the hole could be compromised; the cones have tungsten carbide buttons on them that are very hard so they would have to be fished out of the hole before any more drilling could be done.
We are nearly done with the coring portion of Hole 1301B. Once the coring is done, it will be time to log the hole (send measurement tools down the hole that will measure several of the physical characteristics of the rocks, including porosity, density, natural gamma radiation, electrical resistivity, and more). I sat in on the logging planning meeting today and will share some of that with you.
Many of the basalt core samples that have been drilled are being prepared for chemical analyses. I spent some time in the in the chemistry laboratory tonight visiting with the marine laboratory specialists in the lab about their work.
Here is a partial update for today given by Adam Klaus, Expedition Project Manager/IODP-USIO Staff Scientist (USA):
On the trip out of the hole, we had no serious drag in the open part of the hole and we carefully checked out the previous problem zone inside the 10 3/4-inch casing. Remember, we had met some resistance there on the way in with the last bit. This time there was absolutely no evidence for any problem at this depth. This is a bit of a mystery, but at least has a good ending in that the problem is not there!
CORE-ON-DECK ALERT: Mike's best guess is that we might have core sometime tomorrow before lunch (1200 meal). This depends on: 1) not encountering any problematic sections of hole that need to be reamed; and 2) ~5 hrs to cut the first core.
Countdown to Astoria: 22 days
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 MAKING REPAIRS. The bit change takes about 15 hours including the time it takes to trip the pipe to and from the ship… 3,000 meters is a lot of pipe!!! This break from coring gives the marine laboratory scientists a chance to make minor repairs to the labs.
Trevor Cobine, Marine Laboratory Specialist (Australia), and Lisa Crowder, Marine Laboratory Specialist (USA), have just finished reattaching some of the baseboards in the core lab. There are always “little repairs” that need to be done because of the effects of the sea air.
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 TRIPPING PIPE. The rig floor crew spent all day changing the bit. With about 3,000 meters to pull up and disassemble, it takes them about 4.5 hours to bring up the drill bit to change it. Of course, afterwards they have to take 4.5 hours to go back in. The other 6 hours for this operation are taken changing the bit, and cleaning the hole.
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 We are quickly approaching the end of coring at Hole 1301B. It sounds like there will only be a couple more days so it is important to review the logging plan. This morning Gerardo (Gerry) Iturrino, Logging Staff Scientist (USA), presented the current logging plan. For those of you who know your logging, we are planning to run 4 sets of tools down the hole to measure various physical properties of the hole and the rocks as they are brought back out of the hole. Some of the properties to be measured include the hole diameter, density, porosity, sonic velocity (how fast sound travels through the rock), natural gamma radiation, and structural images of the borehole.
Shown at the table clockwise from the bottom left are: Andy Fisher, Co-Chief Scientist (USA); Tetsuro Urabe, Co-Chief Scientist (Japan); Javier Espinosa, Schlumberger Logging Engineer (Mexico) (glasses on head); Gerardo Iturrino, Logging Staff Scientist (USA); Takeshi Tsuji, Logging Scientist (Japan); Mike Storms, Operations Manager (USA); Mike Hutnak, Physical Properties Specialist (USA); Anne Bartetzko, Logging Scientist (Germany); and (on edge of photo) Rosalind Coggon, Igneous and Metamorphic Petrologist (UK). Keir Beckerr, CORK Hydrologist (USA), is to the left of the table.
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 I found the core photography table. After the core has been sampled and described, the “archive half” is brought to this table and photographed. The photograph is then stored in the IODP database to be used by the scientists. Note the writing on the left side tells us that this core came from IODP Expedition 301, Hole 1301B and is the 26th core to be drilled. The “R” stands for rotary (it was drilled with a rotary core barrel bit).
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 Even though we are not coring right now, there are many samples that are in “the system” and are still being processed. The chemistry lab is gearing up for hard rock (basalt) and sediment sample analyses. Here, Dennis Graham, Marine Laboratory Specialist (USA), is calibrating a titration alkalinity machine using a seawater example. He expects to use this in a couple of weeks to test the alkalinity of pore rocks from sediments that are scheduled to be cored.
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 Eric Jackson, Marine Laboratory Specialist (USA), is preparing a sample of basalt to be placed in the hydraulic press (the black machine against the wall next to Eric) to be crushed. For those who think testing the chemical composition of a rock is easy, read this simplified description of what a sample has to go through to be analyzed: Before Eric can crush the sample, it has to be cut and polished to remove all drilling contamination. After he has crushed it in this press, the rock has to be further ground into a powder. Next, it has to be heated with a flux until it melts to form a glass bead. Once it is cooled, the bead is dissolved in one of several acids. The solution is then diluted. Finally, the diluted solution is fed into in the lab’s Jobin-Yvon JY2000 Inductively Coupled Plasma–Emission Spectrometer (ICP-ES), where it will take approximately 14 hours to perform the chemical analyses of a group of seven samples. According to Eric and Dennis (previous photograph), it takes about 3 full days for a sample to move through this process.
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 The large blue machine is the chemistry lab’s Jobin-Yvon JY2000 Inductively Coupled Plasma–Emission Spectrometer (ICP-ES). Here it is analyzing the chemical composition of a basalt rock sample. If you look closely at this picture, you will NOT see the sample. Part of the rock has gone through the steps described in the caption for the previous picture. The sample that is being analyzed is a solution with a very small part of the rock dissolved in it. If you look on the top of the machine, there are several small plastic bottles in a row. Each of these contain the solution from one rock sample. The solution is being fed into the machine through the thin tube hanging in front of the machine just to the left of the far paper.
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