30 July, 2001

July 30, 2001

Tomorrow we are looking at our last day of field work. After putting in 9 holes at the second site, we have been working the past couple of days at a third drill site. The holes at this site have taken longer to drill because englacial connections have not been encountered until much deeper in the glacier. One of the objectives that we have been pursuing at this site has been to find some of the features that the radar team has elucidated. St. Olaf physics professor Bob Jacobel has found a significant reflector (and object in the ice that reflects the radar pulses that are sent down) at 30 - 40 meters. He is pretty sure that it is an englacial conduit. So, we have spent the past couple of days trying to drill to find it. So far, we have not had any luck.

What we have accomplished over the past few weeks. Many of the goals that initiated this project have been achieved. We feel that we will be returning home with a good set of data. First off, all of our equipment worked well for us throughout the duration of the project. As for scientific results, at each of the drilling sites we encountered englacial drainage during drilling. When the video camera was sent down to take a look we found and recorded physical features that would account for this drainage. These features do not have the physical characteristics of conduits as proposed by previous theoretical modeling. We did some injection pump tests (put a bunch of water into a borehole), and observed water flow in these drainage features. We have set six pressure transducers into various holes and all but one of them appear to be recording water level variations. And the data from these sensors at the outset appears to be pretty interesting. We will leave them to record data for the next few weeks, after which they will be retrieved and mailed to us. The radar group also gathered a good set of data. They did a number of profiles that include reflections of features that are most likely water filled conduits. They also did some imaging of the glacier bed. So, we will be busy processing data when we return home. This is the way that you want things to be when you return from a season of fieldwork.

We will leave Tarfala Forkningsstation (research station) on Wednesday, the day after our last day in the field. We will fly by helicopter to the town of Kiruna, where we will catch an airline to Stockholm, and then home.