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End of Season Field Reports

2014-2015 Field Season

WAIS Divide Borehole Logging 2014-15 Field Season

Field Team:
I-475: Gary Clow
I-172: Ryan Bay, Joseph Talghader, Merlin Mah
I-161: Kiya Wilson, Don Voigt, Nicholas Holschuh, Atsu Muto
I-166: Erin Pettit, Rachel Obbard, Christina Carr, Yasmini Balassoubramaniane (PolarTREC)
IDDO: Mike Waskiewicz, Jim Koehler

19 DEC:

• Setup the logging winch including the level-wind system.
• Setup the sheave-wheels in the arch.
• Tested winch power.

20 DEC:

• Conducted communication tests through the logging winch with the temperature logging system (I-475), Ryan Bay's optical logger (I-172), and the downhole seismometer (I-161).
• All three logging systems passed their communication tests and appear to be working.
• Setup and calibrated the temperature logging system.

21 DEC:

• Ran the temperature logging system all day. No problems were encountered. Temperature tool went past the depth of the deviation ice cores just fine. This log also told us where the bottom of the hole is.

22 DEC:

• Brought the temperature logger back to the surface and recharged system batteries in preparation for the next log.

23 DEC:

• Ran the second temperature log. No problems were encountered. This concluded the temperature logging experiments.

24 DEC:

• Ran the downward leg of Ryan Bay's first optical log. Went past all 5 hole deviations without a problem.

25 DEC:

• Finished Ryan's first optical log and brought the system back to the surface.
• Attempted to do a seismic log but the seismometer did not appear to be picking up a signal.

26 DEC:

• Ran Ryan's second optical log down to 1600 m and back to the surface. This log focused on conditions in the bubbly ice zone. No problems encountered. This concluded Ryan Bay's optical experiments.
• Started the first set of seismic experiments in the evening, beginning at the bottom of the hole.

27 DEC:

• Left the seismometer hanging in the hole at 2500 m during the day. Resumed seismic shots in the evening, incrementally moving the seismometer uphole.

28 DEC:

• Left the seismometer hanging in the hole at 750 m during the day. There was too much wind to conduct any further seismic experiments that evening (wind noise obscures the seismic signal).

29 DEC:

• I-161 decided they had a sufficient amount of seismic data to declare their experiments finished. The seismometer was brought back to the surface. At this point, the temperature, Ryan Bay's optical, and the seismic experiments were done.

30 DEC – 4 JAN:

• No logging was done during this time period while we waited for the other logging teams (Pettit/Obbard I-166, Talghader I-172) to arrive from McMurdo. I-166 and I-172 arrived in camp on 4 JAN.

5 JAN:

• Setup and tested the acoustic televiewer (I-166) on the logging winch.

6 JAN:

• Began acoustic televiewer log #1. The logging speed was 5 cm/s so this log took quite a while.

7 JAN:

• Continued acoustic televiewer log #1. The logger entered one of the deviation holes. We didn't realize this until we got to the bottom of the deviation. We backed out and managed to get past the deviation on the second attempt.

8 JAN:

• Finished acoustic televiewer log #1 at 4am. At 42 hours in duration, this may be the longest geophysical log ever conducted!
• Notified I-172 (Joey Talghader/Merlin Mah) by 8am that the winch and borehole were ready for them to begin logging with their optical tool. They indicated they were having problems with the optical logger. Waited until 3pm at which point they indicated it wouldn't be ready until the next day.
• Erin Pettit was ready to begin her second acoustic televiewer log, we began that about 5pm to minimize the amount of time the borehole was sitting idle.

9 JAN:

• Continued acoustic televiewer log #2. The televiewer again entered one of the deviation holes. It took a couple of tries to get past this deviation.

10 JAN:

• Finished acoustic televiewer log #2. This completed the acoustic televiewer logs.
• Notified Merlin Mah (I-172) that the winch and borehole were again ready for him to log.
• Unfortunately, the logging instrument still wasn't working

10-15 JAN:

• The winch and borehole remained available for optical logging by I-172. The instrument continued to have problems on the bench and so never made it into the borehole.