13 July, 2001
We have drilled 9 holes. Seven of them tapped into some type of englacial drainage system at about 45 to 55 meters depth. We know this because as we were drilling, the drilling water that was filling and overtopping the borehole rapidly descended into the borehole, and out of sight. Later measurements indicated that the water fell into the borehole about 9 meters (50 feet). So, the fall of the water into the borehole was the first indication of what we came here to study! The next task we did was to lower the borehole camera and look for the englacial conduit that drained the water. This is where things became a bit tricky.
We have a sense of where the conduits should be - in our fifth hole the water drained when the drill reached 45 meters. So, that is where the conduit should be located. However, the camera is not seeing a conduit. One would think that an opening in the side of a borehole would be easy to see. However, at this depth the ice is so clear that it is difficult to tell where the borehole wall is located. We observed for lateral parcticle movement indicating englacial flow, and we even lowered a string to look for deflection from englacial water flow. We observed nothing. We have carefully viewed three of the boreholes, and have seen features that we think might be an englacial conduit, but nothing that we can say for sure is an englacial conduit. So, that is our dilemma. We have a few more tricks up our sleeve that we will try tomorrow when we go back into the field.
We had a birthday celebration for St. Olaf undergraduate Peter Pearson. He turned 21. Karin (the cook here at the station) prepared two cakes. Portland State University glaciologist Andrew Fountain, St. Olaf Physics professor Bob Jacobel and myself tied up some balloons to liven up the atmosphere. We had a fun time. By the way, the food here is great.
The tent within which we inspect the interior of the glacier with a borehole camera. The borehole camera is attached to the end of a long video cable that is lowered into the borehole. The images are sent back and viewed/recorded onto a hand-held DV camera.
Portland State University (PSU) glaciologist Andrew Fountain and PSU graduate student Sara Frodin inspect the images of the borehole on the DV camera.
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