July 19, 2017

Brittle ice

The EGRIP skiway is ready for aircraft – a beautiful sight.

Today the drillers produced cores of good quality at a steady pace drilling cores of approx. 1.8 m length each run, so it seems that the filtering operation paid off in terms of easing the drilling operation. In the logging cabin we reached the conclusion that the rotation and cutting of the cores was not feasible any longer due to the ice being too brittle. Hence normal logging operations were ceased and we know push the ice cores directly into storage core troughs. These cores will be logged next year after they have had time to adjust to being at surface pressure. The quality of today cores were generally classified as “fair” using our normal classification system (i.e. complete 1.8 m long cores, but with a few breaks).
On the surface Basile, Nora, Andrew, and Diana dug a pit and drilled a core down to 15.9 m depth. This work was done to bridge the gap from surface down to 15.7 m from where we started storing the AWI test core.
Otherwise the normal programs in the science trench and on the surface continued as planned.

What we did today:

1. Deep drilling core length (from drillers depths) at 19.00: 18.2 m.
2. Drillers depth at 19.00: 680.4 m.
3. Normal ice core logging stopped at 679.24 m (logged depth).
4. Dug 3.4 m pit and drilling hand auger core A5-17 to 15.9 m near AWI test drill site.
5. Documentation and strapping of ice core boxes finished.
6. Water vapour, methane, aerosols, snow and boundary layer measurements
7. Physical properties measurements.
8. Water isotope sampling for sublimation studies.
9. Packing garbage pallet and inspecting skiway

Weather: Sunny turning overcast and the sunny again. Wind turned from SSW to SW during the day, up to 11 m/s, gusting to 15 m/s, drifting snow. Temperatures rising from -19°C to -5°C during the day.

FL, Bo Vinther