Making Use of the Multi-Cores, Who's doing what? Options

[Steve_Marshall]

Monday, 6/20/05 #2
MAKING USE OF THE MULTI-CORES

Now that things are rolling, time is used very efficiently around here. While the multicore was being processed as I described in the previous journal entry, a new piston core was being assembled and deployed. Since I have already posted pictures and journal entries about the deployment of a piston core, I will use my time efficiently too and take pictures of other research going on while the piston core is put in place. When the core comes back up, I will pick up where I left off with the last one...Retrieval of the piston core.

Once the multi core was processed, the various scientists began working on their projects. Another advantage of the multicore is that several scientists can have a core sample to themselves to work on, and still have enough to go around for other scientists and their particular projects. The purpose of this entry will be to give a brief description of some of the projects so you can get an idea of how many different ways sediments can be studied.

Greg Cutter’s Study of Pore Waters in the Arctic Sediments

The first project that began almost immediately was one by Greg Cutter of Old Dominion University in Norfolk, Virginia. One of the things Greg researches is the amount and characteristics of pore water (water trapped in the openings between sediment grains). The reason Greg was able to start almost immediately was that his procedure involves taking sediment directly from the core; The core itself doesn’t need to be transferred to a core liner as described in the previous journal entry.

Below are photographs of some of the stages in Greg’s work. One thing to notice in his whole process is that the sediment is isolated from contact with the skin and air, with the exception of when it is first taken from the core, by several seals in the sediment container he uses, gloves, and air tight work spaces. These procedures help avoid any contamination of the sample, something that is always desirable when conducting scientific research.

Don’t Forget to Measure!

When dealing with sediment cores, even the smallest thickness may represent hundreds or thousands of years, and changes in the sediment can occur quickly, so measuring the core before working on it is very important. Here, Greg Cutter makes sure he doesn’t forget the first step and measures the core thickness.

Taking a Sample

Greg inserts a device to extract part of the core sample for his study of pore waters

Filled to Capacity

Once the sampling device is filled, the sediment is ready to be extracted.

Core Extraction on a Smaller Scale

Cutter places a piston very similar in purpose to those used in extruding the full-sized cores into the bottom of his sample tube. This will allow him to compress the sediment, thus forcing out the pore water.

The Academy Award Pose

As he was cleaning of the sample tube, I thought he was treating it like polishing an award. I asked him to give me his best Academy Award pose…And he did!

Extracting the Pore Water

Forcing the piston up from the bottom, the sediment is compressed and pore water forced into a syringe that can measure the volume of water removed from the sediment.

Uh oh…The Boss is Watching!

Chief scientist, Dennis Darby, looks on as Greg Cutter works to take of sections of the sediment sample once the pore water has been removed.

A Clean Way to Play with Mud

Using good scientific technique, Greg Cutter sections his sample in a contamination-free environment.

Other Research Projects
For sake of space and time running short for the day, I didn’t take as many pictures of the other researchers today, but I do have one or two of some to give a least an introduction to their work:

Looking at the Larger Stuff

Jens Bischof (Old Dominion University), analyzes sand-sized or larger particles for their mineral type and other characteristics. These sized particles are obtained by putting the core sample though different sized sieves (screens) to separate the grains out by size. Here, Jens is looking at those grains to determine where they came from. This gives some information on past ocean currents.

High Tech Instrument

Joseph Ortiz (Kent State University) sets up a spectrophotometer. This instrument indicates very small differences in colors of the sediment, which gives an indication of the sediments composition

The Spectrophotometer in Action

Ortiz is shown moving the spectrophotometer along the length of a split sediment core to determine it luminescent (light/color) properties.

Just Like a Surgeon

Christine Theriault (University of Quebec, Montreal Canada) cuts a sample core into very small increments of 50mm. The sedimentation rate in the Arctic Ocean can be very low, so a very thin layer may represent hundreds or thousands of years, so the thinner you divide the core, the better information you get about changes over time. This is important for Christine’s work, because she will be conducting radioisotope studies in an attempt to determine the age of the sediment.

More Good Lab Techniques

Labeling just about everything is another standard procedure for lab work. Here, several bottles are prelabeled and waiting to be filled. Having things labeled ahead of time helps keep things organized.

I Want to Play Too!

A picture of me taking a sample of a core to bring back to school for grain size analysis and many other yet-to-be-decided experiments. Students like doing labs in the first place; Knowing they’re working with something I brought back from the Arctic Ocean will probably (hopefully) add even more to their excitement!

As I mentioned previously, today was a day of science-filled activities and efficiency. As the studies above were being conducted and brought to a convenient stopping point, the piston core that was put down earlier was ready to come up. Since I missed that part on the last piston core, I went back up on deck to photograph the retrieval of the piston core. That’s another story….