June 18, 2018

Terminating main processing of ice drilled in 2017

Celebrating the science trench: Some of the last bags packed - Thanks to Kerim for providing many of the photos for this flight period.


Today the main processing line of the science trench reached the end of the brittle ice that had been stored in the ice core buffer over the winter. Some 550 m of ice has thus been processed this year by a very steady and hardworking team. Among others, some 5000 samples have been cut for tephra studies alone, more than 1 km of ice core surface has been carefully cleaned with a sharp knife to prepare it to go into the optical scanner, and much of this ice has been brittle ice with cracks that make the processing quite tedious. In the coming days focus will be put on logging the already drilled ice in the buffer and catching up with drilling. We will also investigate at what depth the processing can continue in the coming weeks. Probably some 100-200 m of the still somewhat brittle ice drilled this season needs to rest until later this season or until next year before it can be processed without being compromised. The continuous water isotope analysis and the physical properties measurements will continue unaffected as they are processing at a slower pace. The firn gas drilling is having good progress with three sampling depths a day, but as the depth is approaching the close-off zone, where air bubbles are encapsulated in the ice, the sampling density needs to go up in order to catch the details of that process.

What we did today:

  1. Deep drilling 19.20 m. Drillers’ depth 1162.88 m.
  2. Firn gas drilling sampling to depth 57.65 m
  3. Ice core processing bags 1607 - 1645, final-final depth: 904.75 m
  4. Measurements in isotope laboratory, final depth: 649.00 m
  5. Measurements in physical properties laboratory, final depth 828.85 m
  6. Logging and cutting of this years’ brittle ice 998.62-1025.99 m
  7. Water vapour sampling and measuring.
  8. Digging a 3 m pit S of camp for snow and isotope studies
  9. Blowing trench entrances free of snow

Weather: Overcast - blue sky - overcast. Temp. -11 °C to -16 °C. Wind: 6-16 kt from NW and later W. Visibility: Mostly good. Low contrast morning and evening.

FL, Anders Svensson

Celebrating the science trench: Damiano at the line scanner.

Celebrating the science trench: Tobi at the Swiss saw.

Celebrating the science trench: Eliza and Hamid preparing for celebration.