27 July, 2000

July 27, 2000

Matanuska Glacier, Alaska

This has turned out to be perhaps the busiest day yet. There are more people than ever in camp now and one person who arrived yesterday was Bob Bigl. Bob will be drilling holes in the ice and collecting data from those holes. At one time we thought that we would try some dye tests with a few of these holes. In addition to Bob, my principal investigator Ed Evenson has been here for the past three days to see how things were going and to lend some insight into the project. The entire morning was spent walking around the glacier discussing possible bore sites and strategies with Ed, Bob and Jeff Strasser. Over the next two weeks Bob will be relying on the help of everyone in camp to move and set up his drilling rig at different sites. It looks like even busier days are on the horizon.

After some discussion it was decided that one of the REU students, Isaac Larsen, will conduct the dye study in the drilled holes for his project. Ben and I have only two weeks left before we head back to our homes and it was felt that there wouldn’t be enough time to complete the moulin study and also test the bore holes.We will be working closely with Isaac to get him started since he will essentially be doing what we are but with man-made holes instead of natural moulins. His work should help us in our study because his dye will be infused directly into the subglacial drainage system. Our dye must make its way down through the englacial drainage system (within the ice) before reaching the subglacial drainage (below the ice). By looking at his results we may be able to determine what happens to the dye before it reaches the subglacial system.

We will continue to investigate the connections and flows of dye from the moulin we have used in previous dye tests. Tonight at 8:00 pm we went out to the ice to reprogram three ISCO water samplers. This time we wanted to take samples from all three Mammoth vents that were previously sampled on different days. We poured the dye at 9:00 pm and took samples every ten minutes for four hours. The flow rate into the moulin should be at or near the maximum for a 24 hour period due to the warm sunny daylight hours. We are then going to get up early tomorrow morning and head out to retrieve the samples, place new sample racks in the ISCOs and reprogram them. We will then pour into the moulin again at 9:00 am. These samples should tell us what’s going on at all three vents during low flow resulting from cooler night time conditions.

Marvin Giesting

Pouring the dye into the moulin once again. Look at the picture of this same moulin in the July 20 journal to get an idea of how much it has changed in one week.

We enjoy the fluorescence of the dye in the stream feeding the moulin when we rinse out the bottle. It's amazing how the little bit left in the bottle can cause the stream to get so bright, about like a huge Glo-stick. The dye is so diluted by the time it comes out the vent that you cannot detect it with your eyes.