July 4, 2018

Drilling again

White ash layer on a black backgroung in the EGRIP core. Maybe the Vedde ash.

At EGRIP, the drilling continued, with some runs using step cutters, while other runs were done with traditional cutters in an effort to increase production and reduce the cutter load. So far the step cutter setup is still producing in a more stable mode, but more tests and adjustments are scheduled for tomorrow. Some 11 m of high quality core was produced again today. The processing line and the isotope CFA are all in a good mode with steady production, while the Physical Properties measurements still experience some difficulty with the large area scanning microscope (LASM). Nevertheless measurements of physical properties samples recommenced, just without using the LASM.  In the processing line a distinct white visible layer was seen in ice from the Younger Dryas period, it might be the Vedde ash.
At the RADIX site, drilling preparation continued today, and to our great relief the casing hose loosened without the application of glycol in the hole.

What we did today:

1. 11 meters of main core drilled, new cutter configuration tested and adjusted.
2. Logging of main core from 1321.26 m to 1333.36 m.
3. Processing of EGRIP main core in the science trench, final depth: 1285.90 m.
4. Measurements in isotope laboratory, final depth: 831.60 m.
5. Measurements in physical properties laboratory to 1240.80 m.
6. Water vapour sampling and measuring.
7. Japanese snow crystal and surface monitoring.
8. Preparing for drilling at RADIX site.
9. Installation and test of new warning siren on the dome.

Weather: Cloudy most of the day Wednesday, but getting sunny and clear in the evening. Temperature -17 ºC to -5 ºC. Light or no wind from varying directions until the mid-afternoon, thereafter up to 12 kt wind veering from NW to SW.

FL, Bo Vinther