Setting up NEEM flag line
Last night the Continuous Flow Analysis (CFA) team and the Gas and Isotope Lab (GIL) completed analysis of the deepest section of NEEM main core. ***CONGRATULATIONS*** to all the hard working NEEM participants that have spent days and weeks and months in 12h shifts in the CFA and GIL labs melting close to 2 km of ice sticks at a melt rate of 3 cm per minute. In other words, there has been ice on the melt head for more than 1000 hours. This is a great achievement and it is going to be a great dataset! Now only the Holocene brittle ice needs to be analyzed as well…
The shallow core drilling had a difficult start this morning as the cutters would not engage, but at lunch time the first core came up and production has been good since then. The cores do have a relatively high number of breaks and internal cracks, but the drillers are changing the drill configuration step-by-step trying to improve core quality. In the morning it was almost melting in the drill tent so conditions were not optimal for handling cores, but fortunately temperatures have dropped during the day as the ground fog disappeared and the wind picked up.
What we have done today:
1. NEEM S1 drilling depth 285.45 m
2. CFA of deep main core: bag 4604 – 4607 (2531.65 - 2533.85) The End!
3. CFA of brittle zone main core: bag 2100 – 2109 & 2126 – 2205 (1154.45 - 1212.75 m). 15 m analyzed.
4. NEEM S1 ice core processing: bag 420 - 467 (230.45 - 256.85 m)
5. Setting up flag line on Main Street
6. Maintenance of Pistenbully crane
Ad. 3. The CFA processing of the NEEM main core brittle zone started last night at a depth of 1154.45 m (bag 2100), which is just below the zone of the most brittle ice. The ice was badly broken and generally only unbroken pieces of at least 10 cm length were selected and put together in a composite sample of about 1 m length. At this depth about 30% of the ice could be analysed, whereas the remaining pieces were repacked in the original 110 cm plastic bags. The many breaks require hard work and ample patience for sample preparation and for system maintenance, but it is good to see that CFA analysis of brittle zone ice actually is possible and the core quality is steadily improving with depth. The Picarro continuous water isotope measurements are still online, but the continuous gas analyses were not connected as the many breaks of the composite ice spoil the analyses.
Weather: Ground fog during night and morning. In the afternoon we had clouds and sunny spells. During the evening snow showers and white out. Temp. -3 °C to -9 °C , wind 6 - 15 knots from S in the morning to W in the evening.
FL, Anders Svensson
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