North GReenland Icecore Project - Diary for week 28

Daily reports from the NGRIP-camp - week 28, 2004

Monday, July 5
Daily life
The weather has been a little tough. In the middle of the day, wind speeds reached a maximum of 36 knots, decreasing to 14-18 knots in the evening. Snow is falling, and together with the blowing snow, this limits visibility and the surface definition.
Science
The drilling team is working in 2 shifts, making 7 runs and going 5.5 m further down. The chip chamber was almost full each time, bring up gray "mashed-potatoes" and "couscous" type slush. Preliminary calculations indicate that the top of the refrozen melt water should be reached within the next few days.
Logistics
The weather has limited amount of the outdoor work.

Tuesday, July 6
Daily life

Science
The drill team made 8 runs, penetrating a total of 4.8 m into the slush. The runs were uneventful, and the chip chamber was 75% full every time. We believe that the glycol dropped into the hole on Sarurday has been removed now. The German Dornier team made a measurement flight from Kangerlussuaq to Illulisat and is expected to fly to NorthGRIP Wednesday and Thursday.
Logistics
Cargo for next week's mission period is being prepared. Drifting snow from last days' blizzard has been removed

Wednesday, July 7
Daily life
Windy conditions returned, so more snow will have to be moved.
Science
Today the two teams made 8 runs, gaining 4.5 m into the slush. Most of the runs were uneventful. The chip chamber was 50 - 100 pct. full each time, with gray "mashed potatoes" slush. The Herman Nelson has been used several times to melt out the contents of the core barrel. The second last run of the day apparently yielded a core in the core barrel. To extract the core from the core barrel, the procedures from last year were repeated : The core barrel is put in a basin with drilling liquid to melt the slush. The core appeared only to be refrozen slush however, and the drill current during drilling did not indicate any active drilling. Final depth 3036.25 m. We must be close.... Technical problems with the AWI Dornier have delayed the departure until Thursday.
Logistics
Cargo preparations are ongoing.

Thursday, July 8
Daily life
The oil on the main generator has been changed. It's a special moment, because the sound of the generator is a basic fact of life in camp. The generator is shut down for a about half an hour to change oil and oil filter, and most activities stop and the camp crew suddenly feels the silence.
Science
A 30cm piece of pink bottom water core has been drilled. More details will follow when we get the report from the camp. The AWI Dornier left for NorthGRIP in the morning, but had to return due to bad aviation weather en route. The team will try again tomorrow. From the daily report : Today the two teams made 5 runs. the first two runs were normal slush runs, but with slush also in the core barrel. Chip chamber was 100 pct. full. The next three runs each yielded a pink ice core. Chip chamber was not full anymore. The runs have become more and more like real ice coring. In the last run, the cognac bomb (se last year's dairies for an explanation on what the "cognac bomb" is) was used. However it did not go off. The plastic bag was placed a little too high for the needle to break it. Drilling current rose to 10 A during drilling. At surface it was discovered that one cutter was blocked with ice. The last core had 4 mm of clear ice to one side, indicating that we might already be off center in the hole. Core produced today 0.78 m pink core. Final drillers depth: 3037.9 m. We are in business.
Logistics
The cargo for next week's mission period is ready.

Friday, July 9
Daily life
NGRIP is experiencing a very warm period. The automatic weather station this night measured temperatures above 0ºC.
Science
6 runs were drilled today. The first four runs were a routine copy of last years drilling. During the fifth run the drill developed a short just before drilling. At surface the fault was found: The wire leading from the contacts in the antitorque had been in contact with the antitorque springs. The sixth run produced no core but a 80 percent full chip chamber. We speculate that a piece of ice from the break of the fourth run is causing this trouble. A total of 4.13 m core were drilled today, and after logging the pink core was left in the buffer. Thin sections have been made, and pictures of the crystals in the re-frozen ice were taken through polarized light. The radar team from British Antarctic Survey (BAS) arrived in Kangerlussuaq this afternoon.
Logistics
Kaesbohrers have been repaired and maintained. Weather is reported every two hours, as the radar crew is still waiting for better conditions for their project.

Saturday, July 10
Daily life
The weather is still very warm. Tonight the weekly party will be held. For 8 out of the 11 persons in camp, this could very well be the last Saturday night in the NorthGRIP camp ever.
Science
The drillers made 4 runs today. The four runs were a routine copy of last years drilling. During the first run the drill developed a short. At surface the fault was found: The insulation of one of the screws of the brass contact cylinder in the antitorque had failed. This was repaired, and drilling resumed. The hole that we drill now is not concentric with the old hole, so the core consists of a moon-shaped part of glacier ice and a lens-shaped part of pink refrozen bottom water. The "moon core" of the last run had 42 mm of glacier ice in it. Drillers final depth: 3043.17 m. Logging depth: 3043.15 m. Total core today: 2.93 m Investigations of the core has begun. The people in camp write : We are really exited about the core we see. To one side it is a moon shaped wedge of glacier ice. The rest is pink/red refrozen bottom water. Thin section studies show that the refrozen water has crystals pointing out from the center of the old hole. Small chips of the basal water have been melted in a Coulter cup. The gas release is slow and happens after melting, indicating a presence of carbondioxide. The radar teams are both in Kangerlussuaq waiting for better aviation weather.
Logistics
It was attempted to send out pictures of the special ice cores via satellite phone, but the procedure failed.

Sunday, July 11
Daily life
It has been overcast, but it is getting colder again.
Science
4 mostly routine runs were made today. They had some hard core breaks and one run required three pulls at the maximum torque setting of the winch at 1200 kg. Cores are really good quality, one run gave 1.13 m. The cores drilled today have become more and more white, meaning that only little re-frozen basal water is included now. On the other hand it also means more ice from the Eemian period. A few mysteries turned up during the day: Drillers and loggers have found a 2mm philips screw 10 mm long and a 8 mm allen screw 10mm long in the slush. They are not missed... A few splinters of ice containing red particles from the re-frozen ice were melted in a Coulter beaker. The ice pieces were not cleaned for drlling liquid. After melting the red particles fell to the bottom, but the coulter beaker turned milky on the inside from reaction with a component of the drillers liquid. Also the drillers collected two samples of a special black slush in the chips chamber. These samples, in Coulter beakers, were put in the main dome for melting in the evening. On the following morning the liquid had dissolved the bottom of the Coulter beakers and turned them into a sticky slimy substance. What component of the drilling liquid dissolves polystyrene? We have now taken a Coulter beaker of D60 and a beaker of EWS to see if they dissolve the beakers. Could it be n-butyl acetate? or is it an alien attack? Drillers final depth: 3047.70 m. Total core today: 2.80 m
Logistics
The skiway was zig-zag groomed in preparation of next weeks flights. Snow drifts have been removed.

Continue to Week 29